1. health and fitness

THE HEALTH OF TORONTO’S YOUNG CHILDREN
Volume 2 - The First Year of Life in Toronto
Dr. David McKeown
Medical Officer of Health
February, 2006
Public Health
THE HEALTH OF TORONTO’S YOUNG CHILDREN
VOLUME 2 – THE FIRST YEAR OF LIFE IN TORONTO
February, 2006
Public Health
Reference:
Toronto Public Health. (2006) The Health of Toronto’s Young Children:
Volume 2 – The First Year of Life in Toronto. Toronto, Ontario: Toronto
Public Health
Authors:
Karen Wade, RN, MScN., Karen MacCon, PhD., Wil Ng, MHSc., Jan
Fordham, RN, MEd., Paul Fleiszer, MSc.
Acknowledgements:
The authors gratefully acknowledge the expert review and advice provided
by: Dr. Fran Scott, Donalda McCabe, and Susan Makin.
The authors also greatly appreciate the contributions of the following
Toronto Public Health staff: Camille Anchonu, Alexia Campbell, Teresa
Chong-Low, Winnie Ng Falkenstein, Linda Feldman, Effie Gournis, Simon
Hanukov, Joanne Kaashoek, Olayemi Kadri, Eleni Kefalas, Marian Law,
Jeanette MacDonald, Pauline O’Connor, Dianne Patychuk, Rita PaulSenGupta, Rita Shahin, Nicole Whittingham, Mary Lou Walker, Charles
Yim, and Catalina Yokingco.
Distribution:
Copies of this document are available on the City of Toronto Web Site:
www.toronto.ca/health or from:
Health Information & Planning
Toronto Public Health
277 Victoria Street, 7th floor
Toronto, Ontario M5B 1W2
Phone:
Fax:
Email:
i
416-392-7450
416-338-8126
[email protected]
Toronto Public Health
TABLE OF CONTENTS
EXECUTIVE SUMMARY . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1
PART I: INTRODUCTION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4
PART II: DEMOGRAPHIC CONTEXT . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
Births in Toronto. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
Women Giving Birth . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9
Births by Mother’s Country of Birth . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10
Multiple Births . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12
PART III: BIRTH OUTCOMES . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13
Birth Weight . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14
Healthy Birth Weight . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14
Low Birth Weight . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15
High Birth Weight . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22
Congenital Anomalies . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23
Congenital Infections . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27
Infant Jaundice . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29
PART IV: THE FIRST YEAR OF LIFE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30
Nutrition . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31
Respiratory Conditions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 35
Unintentional Injuries and Poisonings. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 36
Vaccine Preventable Diseases . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 36
Sudden Infant Death Syndrome (SIDS) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 38
PART V: SUMMARY AND CONCLUSIONS . . . . . . . . . . . . . . . . . . . . . . . . . . 39
APPENDIX A: LEADING CAUSES OF INFANT MORTALITY (ICD-9),
TORONTO, 1995-1999 COMBINED . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 43
APPENDIX B: PUBLICLY FUNDED ROUTINE IMMUNIZATION
SCHEDULE FOR CHILDREN (FROM BIRTH TO 18 MONTHS)
BEGINNING IMMUNIZATION IN EARLY INFANCY . . . . . . . . . . . . . . . . . . 44
APPENDIX C: SELECTED VACCINE PREVENTABLE DISEASES AND
THEIR IMPACT ON CHILD DEVELOPMENT AND FUNCTIONING . . . . 45
APPENDIX D: DATA SOURCES AND LIMITATIONS . . . . . . . . . . . . . . . . . 49
APPENDIX E: DEFINITION OF TERMS AND METHODOLOGY . . . . . . . 51
REFERENCES . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 53
The Health of Toronto’s Young Children: Volume 2 – The First Year of Life in Toronto
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LIST OF MAPS
Map 1
Hospital Live Births by Census Tract of Mother’s Residence,
Toronto, 2001-2003 Combined . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8
Map 2
Singleton Low Birth Weight Rates, Area Rates Compared to City Rates,
Toronto, 1996-2000 Combined. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17
LIST OF FIGURES
Figure 1
Model of Child Health . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4
Figure 2
Age-Specific Fertility Rate (per 1,000 women),
Toronto, 1992-2001 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9
Figure 3
Age-Specific Fertility Rate (per 1,000 women),
Toronto and Rest of Ontario, 2001 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10
Figure 4
Healthy Birth Weight Rate (2,500-4,000 grams) per 100 Births,
Toronto and Rest of Ontario, 1997-2003 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14
Figure 5
Total Low Birth Weight Rate (<2,500 grams) per 100 Births,
Toronto and Rest of Ontario, 1997-2003 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15
Figure 6
Singleton Low Birth Weight Rate (<2,500 grams) per 100 Singleton Births,
Toronto and Rest of Ontario, 1990-2001 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16
Figure 7
Singleton Low Birth Weight Rate (per 100 Singleton Births) by Neighbourhood
Income Quintiles, Toronto, 1996-1998 and 1999-2001 . . . . . . . . . . . . . . . . . . . 18
Figure 8
High Birth Weight Rate (>4,000 grams) per 100 Births,
Toronto and Rest of Ontario, 1997-2003 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22
Figure 9
Congenital Anomalies Rate (per 10,000 Births),
Toronto and Rest of Ontario, 1991-2000 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24
Figure 10
Neural Tube Defect Rate (per 10,000 Births),
Toronto and Rest of Ontario, 1991-2000 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26
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Toronto Public Health
Figure 11
Number and Percent of Infants (Birth to 364 Days),
Toronto and Rest of Ontario, 1996-2016 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30
Figure 12
Breastfeeding Initiation Rate and Breastfeeding Duration Rate of 6 Months or
More (per 100) by Mother’s Age at Time of Child’s Birth, Toronto, 2003 . . . . 32
Figure 13
Breastfeeding Initiation Rate and Breastfeeding Duration Rate of 6 Months
or More (per 100) by Mother’s Education, Toronto, 2003 . . . . . . . . . . . . . . . . . 33
Figure 14
Breastfeeding Duration Rates (per 100) Based on the Toronto Perinatal &
Child Health Survey, Toronto, 2003 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 34
Figure 15
Breastfeeding Duration Rates (per 100) Based on the Canadian Community
Health Survey, Toronto, 2000/01 and 2003 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 34
Figure 16
Exclusive Breastfeeding Duration Rates (per 100),
Toronto, 2003 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 35
LIST OF TABLES
Table 1
Number of Live Births by Mother’s Country of Birth,
Toronto and Rest of Ontario, 2001 (ranked by number of births) . . . . . . . . . . . .11
Table 2
Low Birth Weight Rate by Age of Mother and Singleton and Multiple Births,
Toronto, 1999-2001 Combined. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19
Table 3
Causes of Infant Hospitalization,
Toronto and Rest of Ontario, 1997-2001 Combined. . . . . . . . . . . . . . . . . . . . . . 20
Table 4
Congenital Anomalies by Type,
Toronto, 1996-2000 Combined. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25
Table 5
Leading Congenital and Perinatally Acquired Infections in Infants
(Birth to 364 Days), Toronto, 1994-2003 Combined . . . . . . . . . . . . . . . . . . . . . 28
Table 6
Number of Vaccine Preventable Diseases by Episode Year for Reported Cases
Less Than One Year of Age, Toronto, 1994-2003 Combined . . . . . . . . . . . . . . . 37
The Health of Toronto’s Young Children: Volume 2 – The First Year of Life in Toronto
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Toronto Public Health
EXECUTIVE SUMMARY
The Health of Toronto’s Young Children
The Health of Toronto’s Young Children is a series of reports that provide the
most current available information on the health of Toronto children from birth
to age six. These reports provide a picture of the health of Toronto’s youngest
residents. The series of reports uses a model of child health, described in the
first report of the series, as a framework to identify key issues of significance
to young children’s health and indicators of young children’s health. The model
identifies two components of young children’s health - development and
functioning. The model recognizes that injuries, diseases, and disabilities can
seriously reduce young children’s development and/or functioning temporarily,
or in some situations, their health may be affected for their entire lives.
The Health of Toronto’s Young Children: The First Year of Life in
Toronto
This second report in the series, The Health of Toronto’s Young Children: The
First Year of Life in Toronto, focuses on the health of Toronto’s infants from birth
to their first birthday. It provides information on the demographic context of the
first year of life for Toronto’s infants. It also presents information about birth
outcomes, including diseases and disabilities apparent at birth, and highlights the
impact of birth outcomes on short and long term development and functioning.
The report also profiles injuries, diseases and disabilities, as well as resources
during the first year of life (e.g., nutrition), which have an immediate or long
term impact on health. The report summarizes available data and discusses the
significant gaps in local health data related to infant health status reporting.
Highlights from the second report include:
Demographic Context
• Although the number of births to Toronto mothers is decreasing slightly,
close to 25% of all births in Ontario in 2003 were to Toronto mothers.
• Women in Toronto are having children at an older age than women in the rest
of the province. The median age of mothers in Toronto who gave birth in
2000 was 31 years, an increase from 29 years in 1991. In 2000, more Toronto
babies were born to women 40 years or older than to women under 20.
• In 2001, approximately two out of three Toronto babies were born to women
who were born outside of Canada.
Health Behaviours During Pregnancy
• 8.4% of Toronto women who gave birth between 1995 and 2001 reported
having smoked during their last pregnancy, which was significantly less than
the estimate for the rest of Ontario (15.8%). 8.7% of Toronto women who
gave birth between 1998 and 2003 reported they had consumed alcohol.
The Health of Toronto’s Young Children: Volume 2 – The First Year of Life in Toronto
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Birth Weight
• The majority of Toronto babies are born with a healthy birth weight. Toronto
has a higher healthy birth weight rate than the rest of Ontario.
• Toronto’s total and singleton low birth weight (LBW) rates are higher than
corresponding rates in the rest of Ontario. Over time, Toronto’s total LBW
rate has been increasing while the singleton LBW rate has been decreasing.
• Low birth weight and prematurity account for approximately 12% of infant
deaths in Toronto.
• There is considerable variation in the rates of singleton LBW across Toronto.
Rates in some areas of Toronto are 10% to 36% higher than the City’s average
rate of 5.2%. Factors such as neighbourhood income, mothers’country of birth
and maternal age may be contributing to this disparity.
• Between 1999 and 2001, the majority of singleton LBW babies born in
Toronto were born to women between 25 and 34 years old. Adolescent mothers
had the highest singleton and multiple LBW rates of all age groupings.
Congenital Anomalies
• Toronto’s congenital anomaly rate in 2000 was 3.9%, which represents the
first noteworthy decrease since 1995. Continuous monitoring is important
to determine future trends.
• Between 1997 and 2001, congenital anomalies were the third most common
reason for infant hospitalization and the second leading cause of infant
death in Toronto.
Congenital Infections
• From 1994 to 2003, 344 cases of congenital infections were reported in
newborns in Toronto. The leading congenital infections were Hepatitis C
(128 cases), group B streptococci (111 cases), opthalmia neonatorum (37
cases), and HIV/AIDS (36 cases).
Breastfeeding
• The vast majority of Toronto women (approximately nine out of 10) begin to
breastfeed their infants. However, many Toronto babies are weaned early and
less than 20% of healthy term infants are exclusively breastfed for six months.
• In Toronto, older mothers, more educated mothers, and mothers living with
a partner are more likely to initiate and continue breastfeeding. Mothers
born outside of Canada are also more likely to initiate breastfeeding.
Vaccine Preventable Diseases
• The most frequently occurring vaccine preventable disease among Toronto
infants less than one year of age is influenza, followed by varicella
(chickenpox), and pertussis (whooping cough).
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Toronto Public Health
Sudden Infant Death Syndrome (SIDS)
• The proportion of infant deaths due to Sudden Infant Death Syndrome
(SIDS) is decreasing in Toronto. From 1995-1999 (combined), SIDS
accounted for 4% of all infant deaths in Toronto (43 deaths).
Summary and Conclusions
• The picture of Toronto infants’ birth outcomes and health during the first
year of life is incomplete.
• Available data indicates that the majority of Toronto babies have healthy
birth outcomes and reach their first birthday free from major diseases,
disabilities, and injury.
• There is some cause for concern regarding specific health issues such as
LBW, congenital anomalies, and breastfeeding.
• Although the numbers of injuries, poisonings, congenital infections and
vaccine preventable diseases are relatively small, these issues require
continued attention as many of these diseases and conditions are preventable.
• There is a need to continue to monitor the health of Toronto infants and to
obtain a more complete picture of their health.
The Health of Toronto’s Young Children: Volume 2 – The First Year of Life in Toronto
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PART I: INTRODUCTION
The Health of Toronto’s Young Children: The First Year of Life in Toronto, is the
second in the series of reports on the health of Toronto’s young children. These
reports provide the most current available information on the health of Toronto
children from birth to age six. They are intended to assist Toronto Public Health
(TPH) staff, Toronto’s Board of Health, City staff in other divisions, and other
key stakeholders at the local, provincial and federal levels that work with TPH
to improve the health outcomes of Toronto’s young children.
The first report in the series presented a sociodemographic portrait of
Toronto’s young children and their families. It also presented a model of
child health (Figure 1) which provides a framework for identifying key
issues of significance to young children’s health and indicators of young
children’s health.
4
Toronto Public Health
This is the second
in a series of
reports that
provide the most
current available
information on the
health of Toronto
children from
birth to age six.
Health has two
dimensions development and
functioning.
The model identifies that health has two dimensions- development and
functioning. Healthy development involves acquiring the range of skills and
abilities that is possible through the process of physiological maturation.
Healthy development is important to the health of young children because of
the enormous development that occurs in the early years. In the first six years
of life most children develop the basic physical, cognitive, emotional, social,
and communication skills and abilities that they will use in life.1 Healthy
functioning is an age-dependent activity2 which involves using skills and
abilities fully to play, communicate, help others, pay attention, explore spaces,
make friends, form hopes and wishes, and trust and love caregivers. Healthy
functioning also involves having access to and using “inner” (e.g., confidence,
foresight, and resilience)3 and “outer”(e.g., nutritious food, safe living spaces
with room to play, nurturing and responsive care giving, and clean air)
resources needed to cope, adapt, realize aspirations, and satisfy everyday
needs successfully.
Healthy development and healthy functioning usually reinforce each other
positively. However, young children may be developing fully and have brief
periods of diminished functioning. Conversely, children may develop slowly
and yet function fully given their capacity. The model recognises that
injuries, diseases and disabilities can seriously reduce young children’s
development and/or functioning either temporarily or, in some situations,
their health may be affected for their entire lives. Serious deprivation or the
lack of basic resources resulting in issues such as malnutrition or child
maltreatment can have serious immediate and long term effects on
development and functioning.
Healthy
development and
healthy functioning
in early childhood
contribute to
healthier school
age and adolescent
development and
functioning,
thereby increasing
the chances of a
healthy adult life.
Development and functioning during early childhood influence development
and functioning at later stages, creating a ‘health trajectory’ over a lifetime.4
Healthy development and functioning in early childhood contribute to
healthier school age and adolescent development and functioning, thereby
increasing the chances of a healthy adult life.5
The model recognises that young children grow and develop within family,
neighbourhood, community and societal contexts, which influence their
current and future health. Interdependent factors, such as income and social
status, social support networks, education, biology and genetic endowment,
personal health practices and coping skills, physical environments, health
services, healthy child development, gender, culture, and social
environments, may affect children’s health directly or work through their
families, neighbourhoods, and their social and physical environments to
increase or reduce health.6,7 Analysis of the determinants of young children’s
health can facilitate the development of policies and programs to directly
support young children and their families. Initiatives can also be undertaken
to create healthy communities and health promoting social and physical
environments.
The Health of Toronto’s Young Children: Volume 2 – The First Year of Life in Toronto
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This second report in the series – The Health of Toronto’s Young Children: The
First Year of Life in Toronto - focuses on the health of Toronto’s infants from
birth to their first birthday. During the first year of life, development occurs at
a pace unsurpassed in later life stages. Infants develop important physical,
cognitive, emotional, social, and communication skills and abilities. They
make tremendous gains in weight, height, and mobility8 and begin to develop
the ability to initiate and respond to speech, coordinate their vision, and
regulate their emotions.4,9 These capacities provide the foundation for memory,
the ability to use concepts and understand causation, as well as problem
solving in the early years.
This report profiles key aspects of Toronto infants’ development and
functioning. The report also profiles injuries, diseases, and disabilities which
can have an impact on both short and longer term development and
functioning. Some issues are apparent at birth, while others become apparent
during the first year of life, or even later, as children experience challenges in
meeting growth and development milestones or exhibit short or long term
health problems. As well, the report presents data regarding resources, such as
nutritious food, which are necessary for optimal development and functioning.
The health of infants at birth and during the first year of life, as well as their
longer-term health trajectories, is largely dependent on complex interactions
of the determinants of health. Toronto specific data regarding determinants of
health are integrated throughout the report, as appropriate.
Much of the data analysed in this report is represented in the form of trends
over time. Trends are important to monitor because they help to measure
improvement in infant health and identify areas of concern. The extent to
which available data portrays the true, current picture of infant health in
Toronto, is also examined.
Part I of this second report provides background information on the series
entitled The Health of Toronto’s Young Children, explains the focus on the first
year of life, and describes the scope of the report. Part II provides information
regarding the demographic context of the first year of life for Toronto’s infants.
Part III presents information regarding birth outcomes, including diseases and
disabilities apparent at birth, and highlights the impact of birth outcomes on
short and long term development and functioning. Part IV profiles injuries,
diseases and disabilities as well as resources during the first year of life which
have an immediate or long term impact on health. Part V provides a summary
of the report with a focus on the health status of Toronto’s infants and the
significant gaps in local infant health data. It also presents the report’s main
conclusions and provides an overview of future reports in the series The
Health of Toronto’s Young Children.
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Toronto Public Health
This report focuses
on the health of
Toronto’s infants
from birth to their
first birthday.
During the first
year of life,
development
occurs at a pace
unsurpassed in
later life stages.
This report profiles
key aspects of
development and
functioning as well
as injuries, diseases,
disabilities and
resources which
affect development
and functioning.
The extent to
which available
data portrays the
true, current
picture of infant
health in Toronto,
is also examined.
PART II: DEMOGRAPHIC CONTEXT
This section of the report provides an overview of live births in Toronto,
including the number of births,† residential location and age groupings of
women giving birth, and the countries where these mothers were born. This
information sets the context for the discussion of birth outcomes and health
outcomes during the first year of life described in Part III and Part IV
respectively.
Births in Toronto
Close to 25% of all
births in Ontario
in 2003 were to
Toronto mothers.
In 2003, there were 31,362 births to Toronto mothers, a decrease from 32,689
in 1997. This decrease is reflected in the slight decrease in the city’s crude birth
rate since 1997. The crude birth rate (defined as the total number of live births
per 1,000 population) for Toronto in 2003 was 12.0 births per 1,000 persons,
down slightly from 13.1 births per 1,000 in 1997. Although the number of
births to Toronto residents is decreasing, close to 25% of all births in Ontario
in 2003 were to Toronto mothers.‡
Map 1 shows the distribution of births by census tract of mother’s residence.
Census tracts with the darkest shading are those with the highest numbers
of births (see Appendix D-Hospital Birth Data). Births are not evenly
distributed across the City of Toronto, as there are some areas with much
higher numbers of births than others.
†
‡
The term “births” refers to “live births”.
Source: Newborn Inpatient Records, Ontario Hospital Inpatient Data, Provincial
Health Planning Database (PHPDB), Health Planning Branch, Ontario Ministry of
Health and Long-Term Care.
The Health of Toronto’s Young Children: Volume 2 – The First Year of Life in Toronto
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Toronto Public Health
Map 1 - Hospital Live Births by Census Tract of Mother’s Residence,
Toronto, 2001 - 2003 Combined
Women Giving Birth
Between 1992 and 2001, the fertility rates (defined as the ratio of the number
of births to women in a given age group relative to the number of women in
that age group) in Toronto decreased for all age groups less than 35 years old,
while the rates for women aged 35 and older increased (Figure 2).
Women in Toronto
are having
children at an
older age than
women in the rest
of the province.
Women in Toronto are having children at an older age on average than women
in the rest of the province. In 2001, the Toronto age-specific fertility rates for
older women (aged 35 to 49 years) were higher than those of the rest of
Ontario (Figure 3). The local age-specific fertility rates were lower than those
in the rest of the province for all age groups between 20 and 34 years of age.
The largest difference was seen in the 25 to 29 year old age group, where the
rate for Toronto was 40% lower than the rate for the rest of Ontario.
In 2000, more
Toronto babies
were born to
women 40 years
or older than to
women under 20.
As noted in the first report of this series, the average parental age in Toronto
is rising. The median age of mothers in Toronto who gave birth in 2000 was
31 years, an increase from 29 in 1991. The number and proportion of
children born to young mothers under 25 decreased between 1992 and 2000.
In 2001, 12.5% of births were to teen mothers. Almost one quarter (24%) of
births in 2000 were to mothers aged 35 years and older, compared to 16% in
1992. Also, in 2000, more Toronto babies were born to women age 40 or
The Health of Toronto’s Young Children: Volume 2 – The First Year of Life in Toronto
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older than to women under 20 years old. These trends reflect both rising
parental age and the falling birth rate.
Births by Mother’s Country of Birth
In 2001, approximately two out of three Toronto babies were born to women
who were born outside of Canada (Table 1). This indicates greater diversity
among pregnant women and birth families than the Toronto population overall.
Approximately one in every two persons in the City (49%), were born outside
Canada in 2001. In the rest of Ontario, only about one quarter of babies were
born to women who were born outside of Canada.
In Toronto in 2001, the five most common mother’s country of birth other than
Canada were China, India, Sri Lanka, Philippines, and Jamaica (Table 1).
These have remained unchanged since 1999. Compared to other countries of
origin, the greatest increases from 1999 to 2001 were seen in the number of
births to mothers from China (40% increase), Pakistan (35% increase) and
Bangladesh (24% increase).
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Toronto Public Health
Approximately two
out of three
Toronto babies
born in 2001 were
born to women
who were born
outside of Canada.
Toronto and
The Health of Toronto’s Young Children: Volume 2 – The First Year of Life in Toronto
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Multiple Births
Similar to the rest of the province, the Toronto multiple birth rate increased
from 2.1% in 1990 to 2.7% in 2001. This increase may be related to a higher
proportion of pregnancies in older women, and to increases in use of fertility
treatments and assisted conception.10,11 This increase is of particular concern as
twin and especially higher-order multiple births are at higher risk of preterm
birth,12 low birth weight, and perinatal morbidity and mortality.13
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Toronto Public Health
PART III: BIRTH OUTCOMES
This section of the report describes the health of newborns and the
consequences of health conditions at birth on future development and
functioning. Being born healthy is important as it provides a solid foundation
for future development and functioning.
The health of
newborns is
influenced by a
variety of factors.
Although this section of the report focuses on birth outcomes, it is
important to note that the health of newborns is influenced by complex
interrelationships among a variety of collective and individual factors.
Collective factors such as supportive social, economic, and physical
environments, as well as health services, influence individual factors such
as personal health practices, individual capacities and coping skills.6
Modifiable health practices of pregnant women such as nutritional practices,
smoking, alcohol use, unprotected sexual activity, and use of prescription
drugs or illicit drugs such as cocaine, have been implicated in a range of
unhealthy birth outcomes such as fetal alcohol spectrum disorder, low birth
weight, congenital anomalies, and congenital infections.14,15,16,17
8.4% of Toronto
women who gave
birth between 1995
and 2001 reported
smoking during
their last
pregnancy.
8.7% of Toronto
women who gave
birth between 1998
and 2003 reported
consuming alcohol
during their last
pregnancy.
TPH recognizes that these health practices are greatly influenced by the social
and economic environments in which people live, work, and play. However,
because of the modifiable nature of these behaviours, they have been a focus
for public health action at the population level for women planning a
pregnancy as well as pregnant women.
According to the 2000/01 Canadian Community Health Survey (CCHS), 8.4% ‡
of Toronto women who gave birth between 1995 and 2001 reported smoking
during their last pregnancy. This was significantly less than the estimate for the
rest of Ontario in the same year (15.8%§). The Toronto estimate was similar to
that of a recent study18 which showed that 10.4% of new mothers surveyed in
Toronto, Peel and Durham regions, smoked during their pregnancy.
The 2003 CCHS showed that 8.7%** of Toronto women who gave birth
between 1998 and 2003 reported consuming alcohol during their last
pregnancy. This estimate was not significantly different from the 2003
estimate for the rest of Ontario (10.5%†).
‡
§
**
†
High sampling variability. Interpret estimate with caution. Estimate with 95%
confidence interval: 2000/2001 Smoking During Pregnancy Rate for Toronto, based
on CCHS, cycle 1.1: 8.4%, CI95%: 3.3- 13.4%. 2003 Smoking During Pregnancy for
Toronto, based on CCHS cycle 2.1 is not releaseable due to small numbers.
Estimate with 95% confidence interval: 2000/2001 Smoking During Pregnancy Rate
for Ontario excluding Toronto, based on CCHS, cycle 1.1: 15.8%, CI95%: 14.0- 17.7%
High sampling variability. Interpret estimate with caution. Estimate with 95%
confidence interval: 2003 Alcohol Consumption During Pregnancy Rate for Toronto,
based on CCHS, cycle 2.1: 8.7%, CI95%: 4.6- 12.8%.
Estimate with 95% confidence interval: 2003 Alcohol Consumption During Pregnancy
Rate for Ontario excluding Toronto, based on CCHS, cycle 2.1: 10.5%, CI95%: 8.8- 12.1%.
The Health of Toronto’s Young Children: Volume 2 – The First Year of Life in Toronto
13
There is currently no data available on the prevalence of other modifiable
health practices of pregnant women in Toronto, such as prenatal nutrition and
use of prescription / illicit drugs during pregnancy.
Birth Weight
Healthy Birth Weight
A healthy birth weight has been defined in this report as a birth weight
between 2,500 and 4,000 grams. Babies born with a healthy birth weight have
less risk of complications immediately following birth. As well, a healthy birth
weight contributes to healthy development and functioning during infancy,
childhood, and later life.
The majority of babies born in Toronto are born with a healthy birth weight.
From 1997-2003 Toronto consistently had higher rates of healthy birth weight
(singleton and multiple births combined) compared to the rest of Ontario.
Toronto’s healthy birth weight rate decreased from 1997 to 1999 but gradually
increased between 2000-2003 (Figure 4). In 2003, Toronto’s healthy birth
weight rate was 83.6 per 100 births compared to a rate of 80.3 per 100 births
in the rest of Ontario.
14
Toronto Public Health
The majority of
Toronto babies are
born with a
healthy birth
weight. Toronto
has a higher
healthy birth
weight rate than
the rest of Ontario.
Low Birth Weight
However, Toronto’s
total low birth
weight (LBW)
rates are higher
than rates in the
rest of Ontario,
and have recently
been increasing.
Low Birth Weight (LBW) babies include those born prematurely as well as
those born at term gestation but below normal weight (intrauterine growth
restriction).14 Any baby with a birth weight less than 2,500 grams (5.5 lbs.) is
considered to be LBW. Very LBW babies are those weighing less than 1,500
grams (3.3 lbs) and extremely LBW babies are those weighing less than 1,000
grams (2.2 lbs).19
Hospitalization data show that from 1997-2003, Toronto’s total LBW rates
(singleton and multiple births combined) were consistently higher than the
rates for the rest of Ontario (Figure 5). Toronto’s total LBW rate was relatively
stable between1997-2001, but increased in 2003 to 7.2%. This increase needs
to be monitored closely. Among LBW babies born in Toronto in 2003, 20%
(451) were very LBW, and 9% (204) were extremely LBW.
Hospitalization data is the most up to date and complete data source for
calculating total LBW rates. The total LBW rate includes singleton and
multiple births (i.e., twins, triplets, and other multiples). Public health units in
Ontario typically track singleton LBW rates, thus the LBW data presented in
the remainder of this report focuses on singleton LBW rates. The Ontario Vital
Statistics database (2001 is the most recent year for which data are available)
is used as the data source for the remainder of LBW data in this report as it
provides historical data, identifies births as being singleton or multiple, and
contains information related to the mother that facilitates analyses of the
association between selected maternal characteristics and LBW.20
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There is however, an important limitation with this data that must be noted. In
2002, TPH reported that the percent of preterm births (an important factor
related to LBW) in the Ontario Vital Statistics database was overestimated.20
This is due to the fact that in the years 1991 to 1998, the database relied on
parental reporting of gestational age, as opposed to physician reporting.
Parents tend to underestimate gestational age compared to physicians.
Accurate analysis of singleton LBW by gestation is therefore not possible for
this time period.
Figure 6 shows the trend of singleton LBW rates from 1990-2001 for Toronto
and the rest of Ontario. Since 1993, the gap between Toronto’s singleton LBW
rates and the rest of Ontario’s has been consistent, with Toronto’s rates being
higher from 1992 until 2001.The Toronto singleton LBW rate peaked in 1993
and has been gradually declining since then, but has not reached the lowest
rate of 5.0% that occurred in 1990. In 2001, Toronto’s singleton LBW rate was
5.2% with singleton births accounting for 78% (1,560) of total LBW births.
Among singleton LBW babies born in Toronto in 2001, 18% (274 babies)
were very LBW, and 8% (123 babies) were extremely LBW.
Toronto’s singleton
LBW rates are
also higher than
rates in the rest of
Ontario, but have
been gradually
declining.
Toronto’s LBW burden is not evenly distributed across the city. Map 2 shows
the differences in singleton LBW rates (1996-2000 combined) across the city
(see Methodological Details for Map 2 in Appendix E). The singleton LBW
rates in some areas are 10% to 38% lower than the City’s average rate of 5.2%.
In contrast, the rates of singleton LBW in other areas are 10% to 36% higher
than the City’s average rate. Socio-demographic factors such as
neighbourhood income, maternal country of birth, and maternal age may be
Singleton LBW
rates in some
areas of Toronto
are 10% to 36%
higher than the
City’s average.
16
Toronto Public Health
The Health of Toronto’s Young Children: Volume 2 – The First Year of Life in Toronto
17
Map 2 - Singleton Low Birthweight Rates, Area Rates Compared to
City Rates, Toronto, 1996-2000 Combined
contributing to these disparities; however, there is a need to obtain a more
complete understanding of the complex factors contributing to the variability.
Between 1996 and 1998 (combined) the singleton LBW rate in the lowest
income areas in Toronto was 64% higher than the rate in the highest income
areas (Appendix E). Between 1999 and 2001 (combined), the singleton LBW
rate in the lowest income areas in Toronto was 37% greater than the rate in
the highest income areas. Thus, in Toronto, the difference in singleton LBW
rates by neighbourhood income quintile is narrowing (Figure 7). This appears
to be related to a drop in the LBW rate among the lowest income
neighbourhoods while the rate in the highest income areas has remained
fairly stable. A narrowing of the difference between income quintiles may
help to explain the decline in singleton LBW rates observed for the city as a
whole. The distribution of LBW differences by neighbourhood income
quintile in Toronto is similar to differences observed in other urban areas such
as Peel Region and Montreal.21,22
In Toronto, there is also considerable variation in singleton LBW rates
according to mothers’ country of birth, using groupings based on World Bank
Regions (3.6 % to 8.4%, using 1999-2001 combined data). Over the same time
period the differences were even greater when specific countries within World
Bank Regions were examined (2.8% to 10.0%). The reasons for these
18
Toronto Public Health
The singleton
LBW rate in
Toronto’s lowest
income areas
(1999 to 2001
combined data)
was 37% higher
than the rate in
the highest income
areas.
Between 19992001, the majority
of singleton LBW
babies in Toronto
were born to
women between 25
and 34 years old.
Adolescent
mothers had the
highest singleton
and multiple LBW
rates.
Prematurity and
LBW accounted
for approximately
12% of infant
deaths in Toronto
from 1995 to 1999
(combined).
differences are not well understood. Despite years of investigations exploring
the impact of racial/ethnic and social differences on pregnancy outcomes, the
exact pathway is unclear. Researchers suggest that factors such as
socioeconomic status, nutritional deficiencies, stress, social support, lifestyle
behaviours, unplanned pregnancies and prenatal health care interact to
influence pregnancy outcomes.14
Between 1999 and 2001 (combined), although the majority of babies and the
majority of singleton LBW babies in Toronto were born to women between 25
and 34 years old, the proportion of singleton LBW births in Toronto are highest
at the extremes of maternal age (Table 2). Toronto adolescents aged 19 and
under had the highest rate of singleton LBW (7.8%) and multiple LBW
(64.2%) births. Women aged 40 and over had a singleton LBW rate of 6.7% but
the lowest multiple LBW rate (42.3%) compared to women in other age groups.
Being born with a LBW can have consequences for both short and long term
development and functioning. The risk of infant mortality increases with
premature birth (short gestation) and lower birth weight.23, 24 For example,
infants born at 30 weeks gestation (1350 grams) have less than 5% mortality
whereas infants born at 23 weeks gestation (500 grams) have greater than 97%
mortality.24 Preterm birth is the leading cause of infant mortality in
industrialized countries.25 In Toronto from 1995 to 1999 (combined), disorders
related to premature birth and LBW accounted for approximately 12% of all
infant deaths (119 infants) (see Appendix A).
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20
Toronto Public Health
The majority of
LBW babies who
survive function
normally during
infancy, childhood
and adolescence.
However, as a
group they have
an increased
likelihood of
challenges with
development and
functioning.
The vast majority of LBW babies who survive function normally during
childhood and beyond. However, as a group they have higher rates of rehospitalizations, subnormal growth, childhood illnesses (e.g., asthma, upper
and lower respiratory tract infections, and ear infections), neurological
problems, developmental problems and health related limitations.26 Toronto
data show that from 1997-2001 (combined), 16% (11,375) of infant
hospitalizations were related to premature birth and LBW (Table 3). LBW
children from disadvantaged backgrounds are at increased risk of poor
development and functioning compared to socially advantaged children.26
The morbidity among LBW babies has increased due to the survival of much
smaller and more seriously ill infants.27 These babies have the greatest long-term
problems in terms of development and functioning.26,28,29 Very LBW and
extremely LBW infants are frequently cared for immediately following birth in
neonatal intensive care units. They have increased risk of respiratory,
cardiovascular, neurological, retinal and other problems, sensory impairments
(e.g., hearing loss and blindness), and disabilities (e.g., cerebral palsy and mental
retardation) which may have a significant impact on their short and longer-term
development and functioning.24 They often experience physical health problems
that may require frequent medical visits and hospitalizations and their
participation in regular childhood activities may be affected, which can affect the
development of social skills.30 As identified earlier in this report, in 2003, 451
very LBW and 204 extremely LBW babies were born to Toronto mothers.
Research has also identified an association between LBW and delayed motor
and social development during infancy and early childhood,31,32,33 particularly
among babies with medical complications or those who are very LBW.32,34
There is also some evidence that LBW is associated with learning disabilities
as well as poorer cognitive outcomes and academic achievement, 24,35
particularly among children with severe neurological problems, those who are
very LBW/extremely LBW, and/or those exposed to social and/or
environmental risk conditions (e.g., lower socio-economic status, low
maternal education, or poor quality home environment).5,26,28,35,36 Cognitive
deficits associated with social or environmental risk conditions may become
more pronounced over time.26
There is some evidence of an association between LBW and increased
shyness, withdrawn behaviour, conduct disorder, and/or hyperactivity,
particularly among children with cognitive deficits and neuromotor
dysfunction indicative of brain injury and/or those who are very LBW or
extremely LBW.26,34 Research suggests that environmental and social
circumstances may interact with birth weight in terms of children’s social
competence, adaptive functioning, and behaviour.34,37,38,39Interventions for
premature LBW infants and their families can range from provision of extra
stimulation to comprehensive programs including medical follow up, parent
training, and centre-based care for infants. Interventions that begin early in
The Health of Toronto’s Young Children: Volume 2 – The First Year of Life in Toronto
21
infancy and address parental well being, as well as parenting skills, are likely
to be the most useful in promoting optimal developmental outcomes.30
Impaired early growth is a risk factor – not a causative factor – for adult
disease.40 LBW infants have increased susceptibility to coronary heart disease,
non-insulin dependent diabetes, high blood pressure, obstructive lung disease,
high blood cholesterol, and renal damage during adulthood.41 There is
beginning evidence of a possible association between being born very LBW
and increased anxiety/depression, withdrawal and problems with attention
during young adulthood among women.42
LBW infants have
increased
susceptibility to a
variety of chronic
diseases during
adulthood.
High Birth Weight
A High Birth Weight (HBW) baby is usually defined as one with a birth
weight of more than 4,000 grams (8.8 lbs.)43,44 however a cut-off of more than
4,500 grams (9.9 lbs)45 is sometimes used.
In 2003 Toronto’s total HBW rate (>4,000 grams; singletons and multiples
combined) was 9.2%. Since 1997, Toronto’s total HBW rate has been
consistently lower than the rate in the rest of Ontario (Figure 8). The total
HBW rates for Toronto and the rest of Ontario peaked in 1999 and 2000
respectively, and have been gradually declining since then. The difference in
the gap in total HBW rates between Toronto and the rest of Ontario has
remained relatively consistent over time.
22
Toronto Public Health
In 2003, Toronto’s
total High Birth
Weight (HBW) rate
was 9.2%. Since
1997 Toronto’s
total HBW rate
has consistently
been lower than
the rate in the rest
of Ontario.
HBW babies have
an increased risk
of health
challenges and
even death
immediately
following birth.
Perinatal mortality of HBW babies is greater than that of normal sized
babies.46 These babies have an increased risk of difficulties adapting to life
outside the uterus, necessitating admission to neonatal intensive care units,
birth trauma including shoulder injuries and injuries to the nerves in the neck
and underarm, and low blood sugar.44,47 The vast majority of injuries to the
nerves in the neck and underarm (brachial plexus) resolve with no treatment.48
In terms of childhood functioning, there is some evidence of increased risk of
acute lymphocytic leukemia, although the biologic mechanisms need to be
clarified.49 There is preliminary evidence of increased risk of emergency room
visits for asthma during childhood.45 From 1997 to 2001 (combined), 2%
(1,446 infants) of infant hospitalizations were disorders related to long
gestation and HBW (Table 3).
In terms of adult functioning, there is some evidence of increased risk of breast
cancer, particularly premenopausal breast cancer, among women born with
HBW.50,51,52 However, HBW may be a marker for biological or in utero
mediators of risk such as fetal nutrition and/or exposure to maternal estrogen.50
HBW infants born to women with diabetes are at higher risk of developing
obesity and type 2 diabetes.48 The risk of type 2 diabetes associated with HBW
may be reduced in adults with low pre-pubertal BMI.53 There is need for a
fuller understanding of the role of the intrauterine environment in the
development of obesity.54 The relationship between birth weight and obesity
risk may be more common among both HBW and LBW babies.51
Toronto’s
congenital anomaly
rate increased from
3.6% in 1995 to
4.2% in 1999. In
2000, the rate was
3.9%.
Between 1996 and
2000 (combined),
musculoskeletal
and cardiovascular
anomalies
accounted for 51%
of the congenital
anomalies in
Toronto.
Congenital Anomalies
A congenital anomaly is an abnormality of structure, function, or body
metabolism that is present at birth, even if not diagnosed until later in life.16
Toronto’s congenital anomaly rate increased from 3.6% in 1995 to 4.2% in
1999. In 2000, the rate of congenital anomalies in Toronto was 389 cases per
10,000 births (i.e., 3.9% of all live births and stillbirths) which represents the
first noteworthy decrease since 1995 (Figure 9). Data for the years 2000 and
beyond needs to be monitored to determine future trends. These rates
underestimate the true prevalence rates because anomalies resulting in
spontaneous abortions (miscarriages) and terminations of pregnancy are not
included. The rates reflect anomalies occurring in live births, stillbirths, and
infants hospitalized in the first year of life.16
In Toronto, between 1996 and 2000 (combined), the three leading types of
congenital anomalies were: musculoskeletal (24%), congenital heart defects
(18%), and circulatory anomalies (9%) (Table 4). Thus, over half of the
congenital anomalies that occurred in Toronto from 1996-2000 (combined)
were musculoskeletal and cardiovascular anomalies.
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Musculoskeletal anomalies represent a wide spectrum of anomalies of varying
severity which include congenital dislocation of the hip, limb reduction
anomalies, club foot, polydactyly (more than ten fingers or toes), and
syndactyly (two or more fused fingers or toes). Musculoskeletal anomalies in
general, are not usually life threatening. Some resolve spontaneously and
many are correctable with surgical intervention. Some, such as persistent
congenital dislocation of the hip, may have a significant impact on
development and functioning during childhood and even into adulthood,
resulting in chronic pain, gait abnormalities and degenerative arthritis.55 Limb
reduction anomalies may require surgery, physiotherapy and/or occupational
therapy, and a prosthetic device.
Children with congenital heart defects are often born with more than one type
of anomaly. A number of children with congenital heart defects have physical
and developmental limitations. Although advances in diagnosis and surgical
treatment have led to earlier diagnosis and a reduction in mortality and
morbidity; virtually all babies with severe heart defects die within the first year
of life.16,56 Congenital heart defects are the leading cause of deaths attributable
to congenital anomalies in Toronto and in Canada.57
Neural tube defects (NTDs), result from incomplete closure of the neural tube
during the development of the brain and spinal cord.58 Although the rate of
24
Toronto Public Health
Some
musculosketal
anomalies have a
significant impact
on development and
functioning during
childhood and even
into adulthood.
Although
morbidity and
mortality due to
congenital heart
defects has
decreased, virtually
all babies with
severe heart defects
die within the first
year of life.
The rate of Neural
Tube Defects in
Toronto is low.
They can however,
have a serious
impact on
development and
functioning.
NTDs in Toronto is low (1% of all congenital anomalies in Toronto from 19962000 combined) NTDs can have a serious impact on development and
functioning. Infant deaths related to NTDs have declined in Canada over the
last 25 years.57 Sequelae of NTDs may vary from very mild impairments in the
structure of the spinal cord (which are difficult to recognize at birth) to severe
defects involving significant damage to the nerves, spinal cord, and brain.
Babies with anencephaly, a NTD in which the cranial vault and cerebral
hemispheres are missing, die within the first year of life.16 The impact of spina
bifida on development and functioning may range from no physical disability
to lifelong disabilities, including paralysis of the legs, bowel and bladder
incontinence, seizures and mental disability. The impact of these severe
disabilities is profound and can affect all aspects of the lives of the children
and their families.16
In 2000, the rate of NTDs in Toronto was similar to that for the rest of Ontario
(Figure 10). NTD rates in both Toronto and the rest of Ontario decreased from
1991 to 2000. During that time period, the prevalence in Toronto was generally
The Health of Toronto’s Young Children: Volume 2 – The First Year of Life in Toronto
25
lower than that for the rest of the province. Maternal use of folic acid prior to
pregnancy, folic acid fortification of white flour, pasta and cornmeal (which
became mandatory in Canada in 1998),16 as well as increased utilization of
prenatal diagnosis and termination of affected pregnancies (as evidenced by
the increased rate of NTD Therapeutic Abortions in Toronto from 19972000‡), may have contributed to the reduction of NTD birth prevalence in
Toronto and in the rest of Ontario (Figure 10).
Folic acid supplementation of at least 0.4 mg per day at the time of conception
can reduce the risk of NTDs.59,60 According to the Canadian Community Health
Survey (2003), less than half (40%§) of Toronto women who gave birth in the
past five years reported taking folic acid prior to becoming pregnant, down
from 59%† in 2001. In 2001, the folic acid supplementation rate for Toronto was
similar to that for the rest of the province (52%‡‡). However, while the Toronto
rate decreased significantly between 2001 and 2003, the rate for rest of the
province increased to 60%§§ in 2003. These findings suggest the need to
‡
§
†
‡‡
§§
The neural tube defect therapeutic abortion (NTD TA) rate for Toronto increased from
25.5 NTD TAs per 10,000 therapeutic abortions in 1997 to 33.6 in 2000.
Estimate with 95% confidence interval: 2003 folic acid supplementation rate for
Toronto, based on CCHS, cycle 2.1: 40.3%, CI95%: 31.5 to 49.0%.
Estimate with 95% confidence interval: 2001 folic acid supplementation rate for
Toronto, based on CCHS, cycle 1.1: 59.3%, CI95%: 50.4 to 68.1%.
Estimate with 95% confidence interval: 2001 folic acid supplementation rate for
Ontario excluding Toronto, based on CCHS, cycle 1.1: 52.3%, CI95%: 49.6 to 55.0%.
Estimate with 95% confidence interval: 2003 folic acid supplementation rate for
Ontario excluding Toronto, based on CCHS, cycle 2.1: 59.8%, CI95%: 57.0 to 62.6%.
26
Toronto Public Health
Between 1997 and
2001 (combined),
congenital
anomalies were
the third most
common reason
for infant
hospitalizations
and the second
leading cause of
infant death in
Toronto.
Congenital
infections can
cause severe
illness, congenital
anomalies,
spontaneous
abortion, stillbirth
and neonatal
death. From 1994
to 2003, 344 cases
of congenital
infections were
reported in
newborns in
Toronto.
continue and enhance folic acid promotion activities to Toronto females of
reproductive age. Ongoing surveillance of folic acid usage is also necessary.
The short and long-term consequences of congenital anomalies on
development and/or functioning can vary, depending on the specific anomaly
and/or the severity of the anomaly. Between 1997 and 2001 (combined),
congenital anomalies were the third most common reason for infant
hospitalizations in Toronto, accounting for 7% of all infant hospitalizations
(Table 3). In Toronto, congenital anomalies were the second leading cause of
infant death from 1995-1999 combined, accounting for 27% of all infant
deaths (266 infant deaths) (Appendix A).
Congenital Infections
A congenital infection occurs when an infection from a pregnant woman is
transmitted to her fetus or newborn. This transmission can occur when the
fetus is in utero or when the woman gives birth. Congenital infections can
cause severe illness, congenital anomalies, spontaneous abortion, stillbirth and
neonatal death.63 Some congenital infections, such as varicella and rubella, can
be prevented through vaccination. These vaccine preventable congenital
infections will be discussed in the vaccine preventable communicable diseases
section of this report.
From 1994 to 2003 (combined), 344 cases of congenital infections were
reported in newborns in Toronto (Table 5). The leading congenital infections
were hepatitis C (128 cases), followed by group B streptococci (111 cases),
opthalmia neonatorum (37 cases), and HIV/AIDS (36 cases). Some congenital
infections are rare and have not occurred frequently in Toronto over the past
ten years (Table 5).
Hepatitis C is caused by a blood borne virus that slowly affects the liver over
many years. Between 5 to 6 percent of infants born to infected women contract
the infection from their mothers.61 Of those infants, approximately 75-85%
will develop chronic infections.61 Once an infant is infected with the hepatitis
C virus, in most cases the infection will last a lifetime. There is no firm data
on the prognosis of these infected children.61
Pregnant women infected with group B streptococci (GBS) are at risk for
spontaneous abortion, preterm birth and stillbirth. The majority of cases of
GBS disease among newborns occur in the first week of life (75% of cases),
and most of these cases are apparent a few hours after birth.62 Premature babies
are more susceptible to GBS infection than full-term babies, but most (75%)
babies who get GBS disease are full term. Approximately one of every 100 to
200 babies whose mothers’ carry GBS develop signs and symptoms of GBS
disease.62 About 5% to 20% of infants with GBS die and those that survive
may have long-term disabilities.63 Sepsis, pneumonia, and meningitis are the
The Health of Toronto’s Young Children: Volume 2 – The First Year of Life in Toronto
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most common problems.62 These health problems can have both a short term
and long term impact on development and functioning.
Opthalmia neonatorum is an inflammation of the eyes that can result in partial
or total blindness.64 Opthalmia neonatorum is usually caused by maternal
infection with gonorrhea or chlamydia, transmitted to the infant during passage
through the birth canal. Newborns in Ontario are routinely given antibiotic eye
drops or ointment shortly after birth to reduce the risk of infection.
Universal prenatal HIV counselling and voluntary testing guidelines were
introduced in Ontario in December 1998.65 Most infants that have been
infected with HIV during pregnancy, labour or birth appear healthy at birth.
It is therefore, not usually possible to diagnose, by physical examination
alone, whether or not a newborn infant is infected with HIV.66 The diagnosis
is usually made between the ages of six months and two years.67 HIV
infection during infancy can have an impact on development and
functioning, including failure to thrive, developmental delay, and recurrent
infections. Some infants may develop illnesses defining AIDS in the first
year of life, whereas the progression to AIDS may take many years in other
children.68 On average, congenital AIDS occurs in about one quarter of
babies born to HIV infected mothers, with actual rates of transmission
varying from 7% to 71%. Antiretroviral therapy given to pregnant women
and to the newborn infant in the first six weeks of life can decrease perinatal
transmission of HIV by two-thirds.69
28
Toronto Public Health
Infant Jaundice
Jaundice is a yellowish discolouration of the skin, the whites of the eyes
(sclera) and the nails. It is a sign of elevated levels of bilirubin in the blood
(hyperbilirubinemia) caused by the breakdown of red blood cells. Almost all
newborns experience elevated bilirubin levels, but only about half of them
demonstrate observable signs of jaundice. Increased levels of bilirubin in the
blood may be due to physiologic factors, part of the normal changes after birth
or to hemolytic disease.70
Physiologic jaundice related to immaturity of the liver usually occurs 24 hours
after birth and peaks from 72 to 90 hours after birth. In the breastfed infant,
prolonged jaundice into the third and later weeks of life in the healthy newborn
is a normal extension of physiologic jaundice.71 Insufficient caloric intake
resulting from maternal and/or infant breastfeeding difficulties may contribute
to the presence of jaundice.
If untreated, severe
infant jaundice
may have a serious
impact on
development and
functioning such
as hearing loss,
mental retardation,
behaviour
disorders, or even
death.
Between 1997 and
2001 (combined),
7% of Toronto
infant
hospitalizations
were due to
perinatal jaundice.
Hemolytic disease can be caused by a variety of factors, including a blood
incompatibility between a pregnant woman and fetus. This incompatibility
results in a pregnant woman developing antibodies against the blood cells
of the fetus. The antibodies break down the red blood cells of the fetus
causing jaundice. Treatment for hemolytic disease ranges from an injection
given to prevent a mother from developing antibodies against the blood
cells of the fetus in any subsequent pregnancies, placing affected infants
under lights to break down the by products of red blood cells and, in serious
cases, a blood transfusion.72
If untreated, severe infant jaundice may have a serious impact on development
and functioning such as hearing loss, mental retardation, behaviour disorders,
or even death.72
Between 1997 and 2001 (combined), 7% (4,947) of Toronto infant
hospitalizations were due to perinatal jaundice (Table 3). Approximately half
of the hospitalizations were due to newborn cases of jaundice (2,546
newborns), while the other half represent infants who were discharged from
hospital after birth and readmitted to hospital within 30 days for perinatal
jaundice (2,401 infants).
The Health of Toronto’s Young Children: Volume 2 – The First Year of Life in Toronto
29
PART IV: THE FIRST YEAR OF LIFE
In 2001, 28,270 infants lived in Toronto, representing 1.1% of Toronto’s total
population (Figure 11). Although they represent a small percentage, infants are
an important group because they develop a number of capacities during the
first year of life and these capacities form a foundation on which future
development takes place.73 The number and proportion of infants have
decreased slightly since 1996. This slight decrease is expected to continue to
2016 (see Appendix E for details on assumptions for population estimates).
This section of the report describes the health of the youngest segment of
Toronto’s population. The picture of infant health in Toronto is incomplete due
to the lack of Toronto specific population level data. As well, the migration of
infants into and out from the city may distort the true representation of Toronto’s
infant health status. Most of the data presented in this section of the report is
related to indicators of infant functioning. Data is also included on some
indicators of nutrition, which is an important resource for functioning during the
first year of life and beyond. There is no Toronto specific population level data
available on developmental indicators during infancy, a significant data gap.
The health of infants is influenced by a complex set of interacting factors that
operate within the infant, the family, the community in which they live, and the
broader society. Factors such as birth outcomes, infant temperament, parenting
practices, neighbourhood cohesion and economic policies interact in different
ways to influence the health of infants during their first year. These influences
shape not only the health of infants, but their health as children and later, as adults.
At each stage of development, previous health affects current and future health.74
30
Toronto Public Health
The picture of
infant health in
Toronto is
incomplete.
Nutrition
Breastfeeding,
particularly
prolonged and for
exclusive
breastfeeding,
decreases the
occurrence or
severity of a
number of
infectious diseases
during infancy.
There is some
evidence that the
benefits of
breastfeeding
persist into later
childhood and
even adulthood.
A nutritionally adequate diet during the first year of life is essential for healthy
development and functioning. Breastmilk has unique anti-infective and
immunological benefits.75,76 There is strong evidence that breastfeeding
decreases the occurrence or severity of infectious diseases such as
gastrointestinal illnesses, respiratory illnesses, ear infections and urinary tract
infections in infants. Increased duration of breastfeeding and/or exclusive
breastfeeding has been shown to maximize these benefits.76,77 Many studies
suggest a protective effect against development of food allergy in infants with
a positive family history.78 There is some evidence of an association between
breastfeeding and reduced risk of Sudden Infant Death Syndrome and
malalignment of the teeth in the first year of life. There have also been reports
that breastfeeding is associated with slightly improved scores on tests of
cognitive development. There is some evidence that the benefits of
breastfeeding persist into later childhood and even adulthood. Some studies
have reported reduced incidence of diabetes, obesity, lymphoma, leukemia,
Hodgkin’s disease, hypercholesterolemia and asthma in individuals who were
breastfed compared with individuals who were not breastfed.75,79
For the first six months of life breastmilk supplies optimal nutrition. From
approximately six months of age onward, there is a gap between the infant’s
energy needs and the energy provided by breastmilk. Also, after six months
of age, breastmilk alone may not meet the infant’s nutrient needs.80 Continued
breastfeeding with complementary foods is indicated at this time. The
complementary foods should be excellent sources of the nutrients most
limited in breastmilk, most notably iron. Iron depletion leaves the infant
vulnerable to anemia during periods of growth or infection. Even moderate
anemia is associated with depressed mental and motor development in
children that may not be reversible.81
TPH supports the World Health Organization82 and Health Canada83 in
recommending exclusive breastfeeding to six months and continued
breastfeeding for up to two years and beyond.84 Exclusive breastfeeding means
that no food or drink other than breastmilk, including water, with the exception
of undiluted vitamin or mineral supplements or medicines, are included in the
diet. TPH also supports Health Canada’s (2004) recommendation that all
breastfed healthy term infants receive a daily vitamin D supplement from birth
until the infant’s diet provides sufficient vitamin D from other sources or until
the infant reaches one year of age.85 In addition, TPH recommends that iron
rich complementary foods be introduced when infants are six months of age
and when the child demonstrates developmental readiness for these foods.86
By the end of the first year children will be eating a variety of foods from all
food groups as outlined in Canada’s Food Guide.
The vast majority of Toronto women begin to breastfeed their infants.
Estimates for 2003 range from 90% (Canadian Community Health Status
The Health of Toronto’s Young Children: Volume 2 – The First Year of Life in Toronto
31
Survey (CCHS)) to 94% (Toronto Perinatal and Child Health Survey (PCHS)).
Although Toronto’s breastfeeding initiation rates are high, many Toronto
women who initiate breastfeeding do not continue breastfeeding/exclusive
breastfeeding for the recommended length of time. Results from the Toronto
PCHS (2003) show that older mothers (Figure 12), more educated mothers
(Figure 13), and mothers living with a partner are more likely to initiate and
continue breastfeeding than younger mothers, mothers with less than high
school education, and/or lone parent mothers. The same data show that
Toronto mothers not born in Canada are more likely to initiate breastfeeding
as compared to mothers who are born in Canada. Mothers who are recent
immigrants to Canada (been in Canada for 10 years or less) at the time of the
child’s birth are more likely to report that they breastfed their child than
mothers who are not recent immigrants.
32
Toronto Public Health
The vast majority
of Toronto women
(approximately
nine out of 10)
begin to breastfeed
their infants. Many
however,
discontinue
breastfeeding by
six months.
Toronto PCHS data (2003) show that a substantial proportion of mothers who
started breastfeeding stopped after six months and the majority had stopped by
one year (Figure 14). The CCHS results for both 2000/01 and 2003 showed
similar trends (Figure 15). The PCHS and the CCHS estimated a six months
duration rate of 58% and 42%, respectively, in 2003. These rates were
comparable to those for the rest of the province.
By six months, less
than one in five
healthy term
babies in Toronto
are exclusively
breastfed.
Mothers who made their decision about whether or not to breastfeed their
infant before pregnancy were more likely to initiate breastfeeding (96%)
than parents who made their decision during pregnancy (92%) or after
delivery (88%). In addition, those who made their infant feeding decision
before pregnancy were more likely to breastfeed their child for at least six
months (66%) than those who made their decision during pregnancy (50%)
or after the baby’s birth (23%). Mothers who were born in Canada or had
been in the country for more than 10 years at the time of their child’s birth
(77%) were more likely to report that they made their infant feeding decision
before pregnancy rather than during or after pregnancy, as compared to
recent immigrant mothers (who lived in Canada for 10 years or less; 70%).
PCHS data (2003) show that just over three-quarters of all healthy term babies
were exclusively breastfed for two weeks or more. By six months, less than
one in five were exclusively breastfed (Figure 16).
The Health of Toronto’s Young Children: Volume 2 – The First Year of Life in Toronto
33
Breastfeeding Duration
34
Toronto Public Health
Respiratory Conditions
Between 1997 and
2001 (combined),
diseases of the
respiratory system
were the second
most common
reason for infant
hospitalization.
Between 1997 and 2001 (combined), diseases of the respiratory system were
the second most common reason for infant hospitalization. Toronto had a lower
population rate of hospital admissions for diseases of the respiratory system
compared to the rest of Ontario, (109 per 1,000 infants vs. 117 per 1,000
infants). Toronto data show that 15% (10,611) of all infant hospitalizations were
for respiratory conditions occurring during the perinatal period and 9%
(6,118) of all infant hospitalizations were for diseases related to the
respiratory system which occurred beyond the perinatal period (Table 3).
Between 1995 and 1999 (combined), 10% (102) of all infant deaths were
due to perinatal respiratory distress syndrome and respiratory conditions
occurring during the perinatal period. An additional 1% (14) of all infant
deaths was attributed to respiratory system diseases that occurred beyond
the perinatal period (Appendix A).
The consequences of respiratory conditions on infants’ development and
functioning can be short or long term. Perinatal respiratory distress syndrome
is an example of a respiratory condition that can lead to serious long-term
complications in infants and children. It is seen primarily in preterm infants
and is caused by a delay in the development of the lungs.87
The Health of Toronto’s Young Children: Volume 2 – The First Year of Life in Toronto
35
Unintentional Injuries and Poisonings
Between 1997 and 2001 (combined), the rate of hospital admissions for
unintentional injuries among infants during the first year of life was extremely
low.‡ Toronto had a lower rate of hospital admissions for unintentional injury,
including poisoning, compared to the rest of Ontario, (309 per 100,000 infants
vs. 408 per 100,000 infants). In Toronto, falls involving infants under one year
of age accounted for 47% of hospitalizations due to unintentional injuries, while
suffocation/choking and burns accounted for 14% and 9% of injury
hospitalizations, respectively. Poisonings caused 6% of injury hospitalizations
and motor vehicle collisions accounted for 3%. The prevalence of injuries in
infants and children is much greater than that captured by hospitalization data,
which represents only a fraction of the total number of injuries. Many injuries
are treated by family doctors in their office, or in emergency departments,
community clinics or at home. Approximately 1% of all infant deaths in Toronto
between 1995 and 1999 (combined) were related to unintentional injuries and
poisoning (nine infant deaths) (Appendix A).
Between 1997 and
2001 (combined),
the rate of hospital
admissions for
unintentional
injuries among
Toronto infants
was extremely low.
Falls accounted
for 47% of these
hospitalizations.
The consequences of unintentional injuries on children’s development and
functioning are related to the type of injury, the nature of the injury, the age of
the child, and the health care received following the injury. Thus, the
consequences of unintentional injury can range from temporary pain and
inconvenience to permanent disfigurement, disability, developmental delay,
emotional problems and family stress.88 For example, injuries due to falls can
result in abrasions, fractures or trauma to the brain. Traumatic brain injuries
are serious and can be a leading cause of permanent disability.89,90
Unintentional
injuries may result
in temporary pain
and inconvenience
or permanent
disfigurement,
disability, and
developmental
delay.
Vaccine Preventable Diseases
Infants may experience a range of communicable diseases; however, only some
are vaccine preventable. This section will discuss vaccine preventable
communicable diseases that can be acquired in infancy, specifically influenza,
chickenpox (varicella), pertussis (whooping cough), pneumococcal disease,
measles, meningococcal disease, haemophilus influenzae B (Hib), mumps,
hepatitis B, rubella, diphtheria, tetanus, and polio. Other communicable diseases
experienced by children during the early years will be discussed in future reports
in the series. Appendix B shows the currently publicly funded routine
immunization schedule for children beginning immunization in early infancy.
Most vaccine preventable diseases (VPDs) are rare and have not occurred
frequently in Toronto. From 1994 to 2003 (combined), 1,290 cases of these
types of diseases were reported for infants less than one year of age in Toronto
(Table 6). The leading VPDs were influenza (572 cases), followed by varicella
(382 cases) and pertussis (264 cases).
‡
Source: Hospital Separation Data, Provincial Health Planning Database (PHPDB),
Health Planning Branch, Ontario Ministry of Health and Long-Term Care
36
Toronto Public Health
From 1994 to 2003
(combined), the
leading vaccine
preventable
diseases (VPDs)
for Toronto infants
were influenza,
varicella and
pertussis.
VPDs pose varying
degrees of threat
to a child’s
development and
functioning.
All VPDs pose varying degrees of threat to a child’s development and
functioning. Some can cause serious illness and can be potentially life
threatening, while others have mild to moderate effects. Complications from
some diseases can be particularly serious in infants and affect their health in
later childhood and even adulthood. Appendix C contains a detailed summary
of consequences of specific VPDs.
The most frequently occurring VPD among Toronto infants less than one year of
age is influenza. Influenza can result in mild symptoms from which most infants
recover, but some infants can develop serious infections, such as pneumonia,
resulting in hospitalization and death.91
Chickenpox (varicella), including congenital chickenpox (varicella), is the
second most frequently occurring VPD in Toronto infants less than one year
of age. Most infants recover from chickenpox, but complications occur in
about 5-10% of previously healthy infants.91 Infants with weakened immune
systems can develop more severe and longer-lasting symptoms. While the
rates of influenza and chickenpox are higher than other VPDs, their
The Health of Toronto’s Young Children: Volume 2 – The First Year of Life in Toronto
37
consequences to infant and child functioning are generally short-term with
less impact on infant and child development than other less prevalent VPDs.
The third most frequently occurring VPD among Toronto infants less than one
year of age is pertussis. Although pertussis is not as common as influenza and
chickenpox, it can have significant consequences on infant health, resulting in
brain damage, pneumonia and even death. Pertussis in infancy may lead to
learning and behavioural problems during childhood.91
Less frequently occurring VPDs among Toronto infants are pneumococcal
disease, measles, and meningococcal disease. These diseases may have
serious complications. Pneumococcal disease can cause local or invasive
infections. Complications include pneumococcal meningitis, in which
deafness, permanent brain damage, and death can occur. Infection from
measles during infancy can result in serious complications such as
encephalitis, which can lead to permanent brain damage. Meningococcal
disease causes meningitis, which can lead to deafness, brain damage and
death.91
Between 1994 and 2003, there were only a few cases of rubella, rubella
(congenital syndrome), haemophilus influenzae b disease (invasive), mumps,
and hepatitis B in infants under one year of age. Over the same time period,
there have been no cases of diptheria, tetanus, and polio among Toronto
infants less than one year of age. The absence of these diseases in Toronto
over a ten year time period can be attributed to high rates of immunization
against these diseases.
Sudden Infant Death Syndrome (SIDS)
SIDS refers to “the sudden and unexpected death of an apparently healthy
infant usually less than one year of age, which remains unexplained even after
a full investigation”.92 From 1995 to 1999 (combined), Sudden Infant Death
Syndrome (SIDS) was responsible for 4% of all infant deaths in Toronto (43
deaths) (Appendix A). The proportion of infant deaths due to SIDS decreased
steadily from 5.0% in 1990/91 to 3.7% in 1998/99.
Although deaths due to SIDS represent a relatively small proportion of all
infant deaths in Toronto, SIDS is highlighted in this report because even
though the exact cause of SIDS is unknown, factors associated with an
increased risk of SIDS have been identified.92
Health communication campaigns which address these factors have been
developed and implemented.92 However, information on the proportion of
parents/caregivers with knowledge of and adopting practices to minimize risk
of SIDS is not currently being collected.
38
Toronto Public Health
The proportion of
infant deaths due
to Sudden Infant
Death Syndrome
(SIDS) is
decreasing in
Toronto. From
1995 to 1999
(combined), SIDS
accounted for 4%
of all infant deaths
in Toronto (43
deaths).
PART V: SUMMARY AND CONCLUSIONS
During the first year of life, development occurs at a pace unsurpassed in later
life stages. This report, The Health of Toronto’s Young Children: The First Year
of Life in Toronto, focuses on the health of Toronto’s infants during this critical
first year. The report profiles key aspects of Toronto infants’ development and
functioning. It also presents information on injuries, diseases, and disabilities
which can have an impact on both short and long term development and
functioning, as well as resources (e.g., nutrition) which are necessary for
optimal development and functioning.
The picture of
Toronto infants’
birth outcomes
and health during
the first year of life
is incomplete.
Data gaps related
to birth outcomes,
modifiable health
practices, nutrition
during infancy
and developmental
milestones are
significant
because of the
rapid rate of
growth and
development which
occurs during the
first year of life.
The picture of birth outcomes and health during the first year is however,
incomplete. For example, although there is Toronto data on low birth weight,
accurate data on the proportion of Toronto babies born preterm has not been
available. There is currently no population level data on modifiable health
practices of pregnant women in Toronto such as prenatal nutrition and the use
of prescription/illicit drugs.
In addition, data does not exist for resources which have an impact
development and functioning during the first year of life. This includes key
components of infant nutrition such as adequacy and appropriateness of
complementary foods; and nurturing and responsive caregiving or its
opposite- the incidence of violence and neglect. Nor is there data on the
proportion of infants who meet physical, cognitive, communicative and
psychosocial developmental milestones during the first year. These data gaps
are significant because of the rapid rate of growth and development which
occurs during the first year of life. Moreover, growth and development at this
stage of life provides the foundation for growth and development during the
early years and beyond. The lack of population level data on key health
indicators in the first year of life presents challenges in monitoring the heath
status of Toronto infants and planning relevant programs.
The Ontario Government is attempting to address some of the data gaps during
the early years through its Best Start Initiative. A Well Baby Expert Panel is
developing strategies for a province wide developmental assessment for 18
month old children in Ontario.93 Although this initiative will not specifically
address data gaps during the first year of life, it is a beginning step towards
obtaining a more complete picture of child development during the early years.
Work by Toronto Public Health (TPH) has identified concerns with the
integrity of the reproductive health and birth data for Toronto provided by the
Ministry of Health and Long-Term Care.20,94 In order to measure birth
outcomes in a more timely and complete manner, TPH is leading a partnership
of several health units and working with the Child Health Network (CHN) to
implement the “Niday” perinatal database, which collects information on all
births occurring in the GTA. This database provides more timely, complete,
and comprehensive data than other current data sources.
The Health of Toronto’s Young Children: Volume 2 – The First Year of Life in Toronto
39
The analysis of data which is available shows that there is good news regarding
the health of Toronto’s youngest children. The majority of Toronto babies have
healthy birth outcomes. The prevalence of Toronto babies born with selected
congenital anomalies (e.g., neural tube defects) has decreased. Toronto has
lower rates of high birth weight babies than the rest of Ontario.
Most Toronto infants reach their first birthday free from major diseases, disabilities,
and injury. Rates of vaccine preventable diseases and hospitalization for injuries and
poisoning are very low. The proportion of infant deaths due to SIDS has decreased.
The majority of Toronto babies start their lives with the optimal food source breastmilk. Despite this good news, there is some cause for concern about specific
health issues, such as low birth weight (LBW) and congenital anomalies.
Toronto has higher rates of LBW babies than the rest of Ontario. Toronto’s total
LBW rate gradually increased in the last two years for which data are available.
Almost 30% of the LBW babies born in Toronto in 2003 were very low or
extremely low birth weight. Perinatal conditions related to short gestation and
LBW were a leading cause of death in Toronto from 1995-1999 combined.
Toronto’s LBW burden is not evenly distributed across the City. Some areas in
Toronto have rates of singleton LBW that are 10-36 % higher than the City’s
rate. These high rates of singleton LBW may be related to factors such as
neighbourhood income, mother’s country of birth, and maternal age.
The increase in LBW births, the proportion of very low and extremely low
birth weight births, and the disparities in rates of LBW in Toronto needs to be
carefully monitored. The proportion of LBW births in Toronto has the
potential to increase over the next several years, given the increasing numbers
of babies born to older mothers and the high proportion of babies born to
mothers not born in Canada. There is an urgent need to increase understanding
of factors contributing to disparities in LBW in Toronto. LBW babies,
particularly those with concurrent medical or neurological problems and/or
those who are very low or extremely low birth weight and/or those exposed to
social or environmental risk conditions such as poverty, or poor quality home
environment are more likely to require extended hospitalization in neonatal
intensive care units immediately following birth. They also have higher rates
of childhood illnesses, and both short and long term challenges with
development and functioning such as hyperactivity, learning disabilities,
academic underachievement, and chronic illnesses during adulthood. These
challenges require a long term investment in health and social services.
Congenital anomalies are the third leading cause of hospitalization and the
second leading cause of death among Toronto infants. Babies with congenital
anomalies who survive and who have anomalies such as congenital heart
defects and NTDs may experience serious long term disabilities that impact on
development and functioning and require life long services and supports.
40
Toronto Public Health
Available data
indicates that the
majority of
Toronto babies
have healthy birth
outcomes.
Most Toronto
infants reach their
first birthday free
from major
diseases,
disabilities, and
injury. There is
some cause for
concern regarding
specific health
issues such as low
birth weight and
congenital
anomalies.
Although the prevalence of congenital infections in Toronto is low, it is
important to continue to monitor the prevalence of infections such as hepatitis
C, which may become a life-long infection, and group B streptococcus, which
may be contributing to spontaneous abortions, stillbirths, LBW births, deaths
or long term disabilities among Toronto infants.
Despite the high
rates of
breastfeeding
initiation, many
Toronto babies are
not breastfed /
exclusively
breastfed for the
recommended
period of time.
Although the
number of most
vaccine
preventable
diseases among
Toronto infants is
low, there is room
for improvement.
Although there
are low numbers
of infant
hospitalizations
and deaths due to
injuries and
poisonings, many
are preventable
and require
continued
attention.
Despite the high rates of breastfeeding initiation, many Toronto babies are not
breastfed / exclusively breastfed for the recommended period of time. Babies
of younger mothers, less educated mothers and lone parent mothers are less
likely to be breastfed for the recommended period of time. Less than 20% of
Toronto infants are exclusively breastfed for 6 months. Thus, many Toronto
babies are not receiving the maximum protective benefits against
gastrointestinal and respiratory illnesses. Respiratory illnesses are one of the
leading causes of infant hospitalization in Toronto. Premature cessation of
breastfeeding/exclusive breastfeeding is also a concern due to the protective
effect of breastfeeding against SIDS.
Although the number of most vaccine preventable diseases (VPDs) among
Toronto infants is low, there is room for improvement. Influenza and varicella
(chicken pox) are the most frequently occurring VPDs, but generally the
impact on development and functioning is not severe. Although occurring less
frequently, pertussis can have a significant impact on infant and childhood
health, resulting in brain damage, pneumonia and even death. Other VPDs
which have a very low prevalence in Toronto can have mild or moderate to
severe effects on development and functioning. In some cases recovery times
can be long and complications from disease can be very severe. Immunization
for several of the VPDs discussed in this report (i.e. measles, mumps, rubella,
meningococcal disease and varicella (chickenpox)) is not provided until 12
months of age or later (Appendix B). Primary immunization for other diseases
(i.e., diphtheria, pertussis, tetanus, polio, haemophilus B) is recommended at
2, 4, 6 and 18 months of age (Appendix B). Young children are not fully
protected from these diseases until they receive the complete primary
series.95,96 Subsequent reports will highlight the prevalence of these diseases in
the second year of life and beyond.
Although injuries and poisonings are not one of the leading causes of
hospitalization or death among Toronto infants, falls, the leading cause of injury
and poisoning related hospitalizations during infancy, may result in serious
disability, including traumatic brain injury. Suffocation and choking, burns, and
poisonings (combined) accounted for approximately 30% of injury and
poisoning hospitalizations among Toronto’s infants.‡‡‡ These injuries may result
in significant disability and disfigurement. Many injuries and poisonings are
preventable conditions that require continued attention.
‡‡‡
Source: Hospital Separation Data, Provincial Health Planning Database (PHPDB),
Health Planning Branch, Ontario Ministry of Health and Long-Term Care.
The Health of Toronto’s Young Children: Volume 2 – The First Year of Life in Toronto
41
Overall, there is a need to continue to monitor the health of Toronto infants
and to obtain a more complete picture of their health, including disparities in
health outcomes. The first report in this series revealed that nearly three in ten
Toronto children from birth to age five lived in low-income households in
2000. This data suggests that the proportion of Toronto infants living in low
income households is a concern as the impact of poverty on health outcomes
during later childhood and into adulthood is well documented.
Every infant in Toronto deserves and must be given, the opportunity for
healthy growth and development and long term health. TPH in collaboration
with key stakeholders must continue to strive to reach this fundamental goal.
It is also important to have an increased understanding of how the various
determinants of health interact to shape these outcomes in the Toronto context.
This information will help to inform policy levers and program initiatives to
enhance health outcomes for Toronto’s children and decrease disparities in
these outcomes.
The next two reports in this series on the health of Toronto’s young children
will focus on the growing child and the influence of family and
neighbourhoods on children’s development and functioning.
42
Toronto Public Health
There is a need to
continue to
monitor the health
of Toronto infants
and to obtain a
more complete
picture of their
health, including
disparities in
health outcomes.
APPENDIX A:
LEADING CAUSES OF INFANT MORTALITY (ICD-9),
TORONTO, 1995-1999 COMBINED
Cause of death
(ICD-9)
Perinatal conditions
Number
Percent of total
(all causes)
532
52.9
Short gestation and low birth weight
119
11.8
Complications of pregnancy /
complications of placenta, cord &
membranes
115
11.4
102
10.1
Respiratory Distress Syndrome and
other respiratory conditions
Hypoxia / asphyxia
Other perinatal conditions
52
5.2
144
14.3
Congenital anomalies
266
26.5
Ill-defined conditions
100
10.0
Sudden Infant Death Syndrome
43
4.3
Other sudden unexplained infant death
57
5.7
Endocrine, nutritional, & metabolic diseases
& immunity disorders
20
2.0
Nervous system & sense organ disorders
16
1.6
Respiratory system diseases
14
1.4
Circulatory system diseases
13
1.3
Infectious & parasitic diseases
13
1.3
Injury & poisoning
All other causes
All causes total
9
0.9
22
2.2
1,005
100.0
Source: Provincial Health Planning Database (PHPDB), Mortality Data, 1995-1999
Prepared by: Health Information and Planning, Toronto Public Health
The Health of Toronto’s Young Children: Volume 2 – The First Year of Life in Toronto
43
Influenza
Varicella
Meningococcal
Pneumococcal
Rubella
Mumps
Measles
Haemophilus B
Polio
Tetanus
Pertussis
Age at
vaccination
Diphtheria
APPENDIX B:
PUBLICLY FUNDED ROUTINE IMMUNIZATION
SCHEDULE FOR CHILDREN (FROM BIRTH TO 18
MONTHS) BEGINNING IMMUNIZATION IN
EARLY INFANCY97
2 months
.
.
.
.
.
.
4 months
.
.
.
.
.
.
Annually after
6 months
6 months
.
.
.
.
.
1 year
.
.
.
.
.
.
.
15 months
18 months
.
.
.
.
.
.
.
.
.
.
.
.
44
Toronto Public Health
.
.
.
APPENDIX C:
SELECTED VACCINE PREVENTABLE DISEASES AND
THEIR IMPACT ON CHILD DEVELOPMENT AND
FUNCTIONING91
Disease
Effects of disease
Diphtheria
Most often infects the nose or throat. Some strains produce a
toxin that can cause severe damage to the throat or other
tissue. The toxin can also attack the heart, nerves and
kidneys.
Spread by nasal droplets from coughing and
sneezing.
Person is infectious for up to two weeks.
Tetanus
Severe disease caused by a toxin. Toxin is
made by bacteria that is present in soil, dust
and animal feces.
Infection can lead to complications such as suffocation, heart
failure, nerve damage, and kidney failure.
The toxin blocks normal control of nerve reflexes in the spinal
cord, resulting in intense stimulation of muscles throughout
the body. Muscle contractions may cause death by interfering
with breathing.
Bacteria enters the body through cuts or
wounds. It is not passed from person to
person.
Even with treatment in a modern intensive care unit, the death
rate is 10-20%. Other complications include suffocation,
choking spells due to difficulty swallowing, weight loss due to
poor eating, bone fractures from severe muscle spasms,
pneumonia, skin ulcers, and lasting difficulties with speech,
memory and mental function.
Pertussis (whooping cough)
Minor complications include nosebleeds, swelling of the face
and ear infections.
Spread by cough and nasal droplets.
Symptoms include runny nose and irritating
cough, which may develop into whooping
cough.
Coughing spells can last for weeks.
Recovery can be slow and typically lasts six to
12 weeks.
Severe complications in children include collapse of the small
area of the lungs due to thick mucus blocking the airways.
These areas are often invaded by other bacteria or viruses,
causing pneumonia.
About 20-30% of infants less than 12 months old are
admitted to hospital because they often stop breathing
instead of coughing. Such attacks may lead to convulsions
and coma.
1 in 400 infants with pertussis suffers permanent brain damage
and 1 in 400 dies as a result of pneumonia or brain damage.
Studies have shown that children who had pertussis in
infancy have a much higher rate of learning and behavioural
problems.
Infection may lead to fever, headache, nausea and vomiting,
muscle weakness and paralysis.
Polio
Spread by feces and saliva.
Most infections with poliovirus occur without
any noticeable illness.
In its most severe form, poliovirus can infect and destroy
nerve cells in the spinal cord that control the contraction of
muscles. When the nerve cells die, the muscles become weak
or paralyzed. Nerve damage is permanent. 1 out of every 100
persons infected gets paralytic polio. Recovery of muscle
function may occur, but most patients are permanently
paralyzed.
Complications include death and post-polio syndrome, a
progression of muscle pain, weakness and paralysis suffered
by those who have had paralytic polio. The interval between
the original illness and the onset of new symptoms may be as
long as 15 to 40 years.
The Health of Toronto’s Young Children: Volume 2 – The First Year of Life in Toronto
45
Disease
Effects of disease
Haemophilus influenzae type b (Hib)
Spread by nasal droplets.
Hib causes a variety of infections. The most common and
least severe are infections of the nose and throat without any
illness.
Usually infects children under two years of age.
Presents as an acute illness with fever,
vomiting and lethargy in 55-65% of cases.
Hib can also cause infection of a joint or a bone resulting in
pain and decreased movement, as well as infection of the ear,
sinus, eye, respiratory tract, and lungs (pneumonia).
Hib is the leading cause of bacterial meningitis (an infection of
the fluid and lining that cover the brain and spinal cord) in
infancy, which can lead to permanent brain damage.
About 1 in 5 children who survive Hib meningitis will
experience blindness, deafness, mental disability or a learning
disability.
Measles
Severe and highly contagious illness caused by
a virus.
Spread by cough and nasal droplets.
Symptoms include fever, sore throat, runny
nose, itchy eyes and a red rash that starts on
the face and spreads to the rest of the body.
The illness lasts, on average, one to two
weeks.
Most people recover from measles but
complications are very common in infants and
adults.
Infection can cause damage to the respiratory tract, lymph
glands, spleen, liver, intestines, and skin. Many infants and
young children with measles get diarrhea as a result of
damage to the intestinal tract.
Also impairs the function of white cells, affecting the ability of
the immune system to respond to infection.
Encephalitis (inflammation of the brain) occurs in about 1 in
every 1,000 cases, often resulting in permanent brain
damage. Symptoms include fever, seizures and impairment of
consciousness. Many children go into coma. There is no
treatment for measles encephalitis. About one-third of
children with encephalitis die, one-third have significant brain
damage and one-third recover.
Almost all children have high fever, severe cough, poor
appetite, and are so sick that they are in bed for a week or
more.
About 1% of children are hospitalized because of measles or
related complications.
Measles can also cause death. In rare cases, a severe and
always fatal brain disease called SSPE (subacute sclerosing
panencephalitis) develops years after the person has had
measles.
Mumps
Spread by saliva.
Symptoms include fever, headache, and
swelling of the salivary glands around the jaw
and cheeks.
Most common complication of mumps is meningitis. About 1
in every 10 people with mumps gets meningitis, which is
usually mild and does not cause permanent damage.
Infection can also cause encephalitis, which occurs more
frequently in adults and may lead to permanent brain damage.
Most children recover within 14 days.
Infection with mumps can also cause deafness in children.
Rubella
Rubella is not a serious illness in children, however, it can
cause death or severe malformation of the fetus (congenital
rubella syndrome) if a pregnant woman becomes infected
during the first 20 weeks of her pregnancy. Most children born
with this syndrome are severely handicapped.
Spread by nasal droplets.
Symptoms include fever, headache, itchy eyes,
sore throat, swollen glands, rash, aches and
pains, redness of the eyes, and joint pain.
Symptoms and complications are most common in
adolescents and adults.
Encephalitis occurs in about 1 in 6,000 cases.
46
Toronto Public Health
Disease
Effects of disease
Pneumococcal Disease
Spread by saliva and nasal droplets.
Local infections which include infections of the ears, sinus,
airways, or lungs.
Most common cause of bacterial infections in
children and a frequent cause of infections in
adults.
Invasive infections which include infections of the blood,
central nervous system, heart, joints, bones and abdominal
lining.
The most common type of illness is middle ear infections.
Infection starts in the nose or throat but many
people do not develop any symptoms of illness
after infection (carriers). Spread of the disease
most often involves carriers.
Complications include pneumococcal meningitis, in which
deafness, permanent brain damage, and death can occur.
Meningococcal Disease
Causes meningitis, an infection of the lining of the brain and
spinal cord caused by a bacteria.
Spread by saliva and nasal droplets.
Infection starts in the nose or throat but many
people do not develop any symptoms of illness
after infection (carriers). Spread of the disease
most often involves carriers.
Deafness occurs in 1-2% of survivors of meningitis.
The disease can also cause infection in other body parts, as
well as serious infection in the blood, and inflammation of the
brain, which can lead to brain damage and death.
Symptoms include a characteristic rash, flu-like
illness, headache, and stiff or painful neck.
Varicella (Chickenpox)
A highly contagious infection, but a mild to
moderate illness in the majority of children. Its
complications can be severe.
Symptoms include fever, headache, aches and
pains, and a very itchy rash with sores.
Sores will continue to appear daily for three to
five days. Fever, aches and pains generally last
one to two days. Most children feel better and
are able to return to school or other activities
one week after the start of the rash.
Hepatitis B
An infection of the liver caused by a virus.
Most commonly spread by penetration of the
skin with virus-contaminated equipment or
fluids and/or exposure of membranes of mouth
or genital tract to blood or to body fluids
containing blood.
Half of the people who are infected do not
know they have the virus because they do not
get sick (asymptomatic). The other half
become ill with fever, fatigue, loss of appetite,
and yellow skin and eyes (symptomatic).
Complications occur in 5-10% of previously healthy children
with chickenpox, leading to hospitalization and, in rare cases,
death.
Most common complications are pneumonia, encephalitis,
and inflammation of the cerebellum (part of the brain).
The average length of hospital stay for infants age 0-1 is 5.5
days.
Infants, adults, and those with weakened immune systems
tend to have more severe and longer-lasting symptoms. They
are at higher risk of developing encephalitis and pneumonia.
Chronic carriers (about 10% of asymptomatic cases) may
develop liver disease or liver cancer many years after
becoming infected, which may lead to scarring of the liver
and death from liver failure.
More than 90% of infants who acquire hepatitis B at birth
from their infected mothers will develop chronic infection.
Acute illness (symptomatic cases) may last weeks or months.
Severe liver damage caused by infection may be fatal. Most
people recover from the acute infection and are immune for
life. The illness is usually milder in children than in adults.
1 out of 100 acute infections are so severe that the liver stops
working and there is a high risk of death.
In Canada, the infection rate is highest among older
teenagers and young adults. The rate of infection in infants is
decreasing due to testing during pregnancy and the
availability of vaccine plus hepatitis B immune globulin.
The Health of Toronto’s Young Children: Volume 2 – The First Year of Life in Toronto
47
Disease
Effects of disease
Influenza
During outbreaks of the flu, there is an increase in the
hospitalization and death rates of infants (less than 12 months
old) and elderly persons (age 65 and over).
A rapid-spreading and ever-changing virus
(almost every year) that causes epidemics of
flu, bronchitis (infection of the airways) and
pneumonia (infection of the lungs) in the late
fall or winter.
Spread by releasing secretions into the air
through coughing, sneezing, talking and
singing. Also spread from person to person
when contaminated droplets are released or by
touching contaminated surfaces and then
touching the fingers to the nose or eyes.
The vaccine only provides immunity for one
year.
Most people who get the flu recover
completely in one to two weeks, but some
people develop serious and possibly lifethreatening complications, including death.
48
Infection results in a wide range of illnesses that can include:
•
infection without any symptoms;
•
common cold-like illness with or without fever;
•
sudden onset of fever, headache, aches and pains,
fatigue, sore throat and cough;
•
high fever without other symptoms, especially in infants
and young children;
•
croup in children less than two years of age;
•
fever and convulsions in infants and young children; and
•
fever, vomiting, abdominal pain and diarrhea, with or
without respiratory symptoms, especially in infants and
young children.
Pneumonia is the most common complication and common
cause of death from influenza. Other complications include:
•
febrile seizures in infants and young children;
•
myositis (severe muscle inflammation) in children with
influenza B infection, primarily affecting the calf muscles in
both legs;
•
myocarditis (inflammation of the heart muscle), which may
lead to abnormal health rhythm, heart failure and death;
•
encephalitis (inflammation of the brain), which may lead to
brain damage and death;
•
Reye’s syndrome, a rare condition that causes damage to
the brain and liver.
Toronto Public Health
APPENDIX D: DATA SOURCES AND LIMITATIONS
Canadian Community Health Survey (CCHS) 2000/01 and 2003
The CCHS is conducted by Statistics Canada using face-to-face and telephone
interviews. The target population of the CCHS is Canadian household residents
aged 12 years and over in all provinces and territories, with the exclusion of
populations on Indian Reserves, Canadian Forces Bases, and some remote areas.
The survey sample size for Toronto was 2,382 in 2000/01 and 3,107 in 2003.
When necessary, the survey was translated into Chinese, Punjabi and Inuktitut.
Canadian Congenital Anomalies Surveillance System (CCASS)
The CCASS captures information on congenital anomalies among stillbirths,
live births and hospitalizations in the first year of life from hospital records
and through other provincial systems.16 Limitations of the system include the
inability to monitor the impact of prenatal diagnosis on the birth prevalence of
selected congenital anomalies, lack of outpatient data, lack of reporting from
some hospitals, exclusion of data on affected infants admitted to hospitals for
other reasons, and exclusion of most prenatally diagnosed anomalies that
result in terminations of pregnancy.
Census Data
Conducted by Statistics Canada, the Census provides information about
Canada’s demographic, social and economic characteristics. Information can
also be obtained for smaller levels of geography such as cities and areas within
a city. The Census undercounts some groups, such as the homeless, young
adults and aboriginal people on reserves.
Hospital Birth Data
Hospital birth data captures births occurring in Ontario hospitals. While it does
not capture at-home births, it does include unregistered births, thereby making
it more complete than vital statistics data. Another limitation of hospital birth
data is that the neonate’s record cannot be accurately linked to the mother, thus,
this source is not being used for variables associated with the mother such as
maternal age, single versus multiple births, etc. For analysis of hospital births
by census tracts (Map 1), newborn inpatient records assigned to Toronto were
allocated to census tract by postal code of residence. Records with missing,
incorrect or non-Toronto postal codes could not be allocated to a census tract.
Live Birth Data – Vital Statistics
The Office of the Registrar General collects vital statistics data using the
“Statement of Live Birth” form completed by parents, and the “Physician
Notice of Birth” completed by the attending medical professional. Only births
The Health of Toronto’s Young Children: Volume 2 – The First Year of Life in Toronto
49
with both pieces of documentation are entered in the database. The last estimate
in 1997 showed that 3.2% of Toronto live births were unregistered and
unreported. The percentage of unregistered births is higher among births to
mothers less than 20 years of age, low birth weight births and pre-term births.
Mortality Data
The Office of the Registrar General obtains mortality data from death
certificates that were completed by physicians. Residential information is based
on the deceased person’s geographic place of residence. Since 1993, Ontario
residents who died outside of the province are excluded from the Health
Planning System (HELPS) database. Out-of-province residents who died in
Ontario are also excluded. Causes are those that initiated the sequence of
morbid events leading to death, and co-morbidity can contribute some
uncertainty as to underlying cause(s) of death. Variation in data collection
procedures over time and/or geography may reduce the accuracy of time and/or
place-specific comparisons.
Population Projections
Detailed population projections are produced for the 30 year period following
every Census, in this case the 2001 Census. Assumptions used in the
calculation of these projections are described in Appendix E.
Reportable Disease Information System (RDIS)
Toronto Public Health is responsible for collecting case information on
reportable communicable diseases. The majority of cases are identified
through laboratory notification of confirmed test results. Physicians are
required to report cases that fulfill laboratory or clinical case definitions.
There is possibility of considerable under-reporting of cases for some
communicable diseases.
Toronto Perinatal and Child Health Survey (PCHS), 2003
Conducted by Toronto Public Health, the PCHS is a population based survey
that describes the prevalence of selected risk and protective factors related to
child health outcomes in Toronto. One thousand randomly selected parents
with children from birth to age six, residing in the City of Toronto participated
in this survey. Interviews were only conducted in English, hence results may
not be generalizable to the non-English speaking population. The survey also
over-represents mothers, parents with higher education levels, and parents who
are not recent immigrants.
50
Toronto Public Health
APPENDIX E: DEFINITION OF TERMS AND
METHODOLOGY
International Classification of Diseases (ICD)-9
The International Classification of Diseases (ICD) is used to classify diseases
and other health problems recorded on many types of health and vital records
including death certificates and hospital records. The Ninth Revision of the
ICD was approved by the 29th World Health Assembly in May 1976 to come
into effect January 1, 1979. ICD-9 was adopted in Canada in 1979. ICD-9
contained 17 chapters plus two supplementary classifications: the
Supplementary Classification of External Causes of Injury and Poisoning (the
E code) and the Supplementary Classification of Factors Influencing Health
Status and Contact with Health Services (the V code).
Methodological Details for Map 2
Map 2 shows Toronto’s 41 local health planning areas. All city singleton
low birth weight (LBW) rates are derived from postal codes beginning with
the letter M only. Each area’s singleton LBW rate is compared to the city’s
rate of 5.2%.
Neighbourhood Income Quintiles
In the ‘Births in Toronto’ and ‘Birth Weight’ sections, differences in the
distribution of births and low birth weight (LBW) rates were examined
according to neighbourhood income quintiles. Neighbourhood income
quintiles are commonly used in population health research as an indicator of
socio-economic disparities in health. Population quintiles are defined
according to methods developed at Statistics Canada, based on postal code of
place of residence and the Statistics Canada Census income information for
the geographic areas (such as census tracts) that the postal codes are assigned
to. The rate for the 20% of the population living in the highest income
neighbourhoods (i.e., census tracts) is compared to the rate for the 20% of the
population in the lowest income neighbourhoods (census tracts). The
difference in rates according to income level is often called the social gradient
in health where populations at each step up the income scale have better health
than groups on the step below.
The rate achieved by the population living in the highest income areas may be
considered to be potentially achievable for the population as a whole if the rate
in each of the other income quintiles can be brought to the same level as that
achieved in the wealthiest neighbourhoods. The number of events that would
have occurred if all population groups had the same rate as the 20% of the
population in the highest income quintile are called “income-related excess
events” (e.g. births, deaths, hospitalizations, etc.).98 When places set targets for
reducing health disparities, income quintiles examined over time are often
The Health of Toronto’s Young Children: Volume 2 – The First Year of Life in Toronto
51
used to gage progress on bringing lower income groups closer to the rates of
higher income groups; and to ensure that progress achieved on the overall
population or city rate is accompanied by a reduction in health disparities.
In LBW analysis, multiple births which are more likely to be LBW are usually
excluded in order to make the quintiles more comparable on a population
basis.
Population Projections
Population estimates, as shown in Figure 11, were calculated using the
following assumptions for fertility, mortality, and migration:99
Fertility
The total fertility rate for the province is assumed to increase slightly from
1.53 to 1.55 children per woman by the end of the projection period. This is an
almost constant fertility assumption, and mean age at childbirth is assumed to
increase to 31 years.
Mortality
Life expectancy for Ontario is assumed to increase from its recent level to
reach 81.0 years for males and 84.5 years for females by 2028. Male life
expectancy is expected to progress at a faster pace than female life expectancy.
Migration
The immigration level for Ontario is set at 115,000 at the beginning and is
increased to 120,000 in 2004-2005. This level is held constant thereafter.
52
Toronto Public Health
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