THE GRADUATE COLLEGE OF THE
UNIVERSITY OF OKLAHOMA HEALTH SCIENCES CENTER
ANNOUNCES THE FINAL EXAMINATION OF
Amanda Elizabeth Janitz
For the Defense of the Doctor of Philosophy Degree
GRADUATE COLLEGE
Department of Biostatistics and Epidemiology
Monday, May 4, 2015, 11:30 am
College of Public Health, Room 307
EVALUATION OF THE ASSOCIATIONS BETWEEN CONGENITAL
ANOMALIES AND CHILDHOOD CANCER AND BETWEEN MEASURES OF
AIR POLLUTION AND CHILDHOOD ACUTE LEUKEMIA
COMMITTEE IN CHARGE: Jennifer D. Peck, Ph.D., Chair, Janis
E. Campbell, Ph.D., Julie A. Stoner, Ph.D., Sheryl L.
Magzamen, Ph.D., Anne E. Pate, Ph.D.
ABSTRACT: Although rare, childhood cancer is the leading cause of disease-related
deaths among children in the US. While few risk factors have been identified, studies
indicate children with anomalies have a higher rate of childhood cancer and air
pollution may be associated with acute leukemia. Using data collected by the
Oklahoma State Department of Health, we evaluated whether the association
between congenital anomalies and childhood cancer varied with age through a
retrospective cohort study. Subsequently, we conducted a case-control study to
assess whether children with acute leukemia had a higher odds of exposure to
benzene compared to controls identified from birth certificates matched 4:1 on
week of birth. We measured benzene using the US EPA’s 2005 National-Scale Air
Toxics Assessment at the census tract of birth for Oklahoma. Using the same study
population, we also evaluated exposure to traffic-related air pollution, measured
through satellite-based land-use regression estimates of nitrogen dioxide (NO2) for
2006 at the census block at birth and high density roads within 500m and 750m
from the residence at birth. In our evaluation of congenital anomalies and childhood
cancer, we detected an increased hazard of any childhood cancer in children with
anomalies compared to those without anomalies before one year of age (HR: 14.1,
95% CI: 8.3, 23.7) and at three years of age (HR: 2.3, 95% CI: 1.6, 3.2), with the effect
diminishing by six years of age. We observed similar results when evaluating any
anomaly in relation to specific cancers and specific anomalies in relation to any
cancer. In our evaluation of benzene, we observed stronger estimates for children
with AML compared to those with ALL adjusted for maternal education and
urbanization (4th Quartile OR for AML: 2.42, 95% CI 0.98, 5.96). In our analysis of
traffic-related air pollution, we also observed a positive association between NO2
and AML adjusted for maternal education among urban children (4th Quartile OR:
5.25, 95% CI: 1.09, 25.26), but no association between road density and acute
leukemia. The results from this dissertation suggest continued evaluation of
environmental risk factors for childhood cancer is warranted.