Oral session 7: Epidemiology
O7.1
Sole Searching: What happens when nearly 2 million people with diabetic foot ulcers
walk into outpatient clinics?
Grant Skrepnek, The University of Oklahoma Health Sciences Center; Southern Arizona
Limb Salvage Alliance, Oklahoma City, OK, United States
Joseph Mills, The University of Arizona; Southern Arizona Limb Salvage Alliance, Tucson,
AZ, United States
David Armstrong, The University of Arizona; Southern Arizona Limb Salvage Alliance,
Tucson, AZ, United States
Aim: To evaluate ambulatory clinical cases of diabetic foot ulcers (DFUs) in the U.S. from
2006-2010 and assess outcomes of emergency department referral or inpatient (ED/IP)
admission, number of clinic visits per year, and physician time spent per visit.
Methods: This cross-sectional study utilized the nationally-representative Centers for
Disease Control (CDC) National Ambulatory Medical Care Survey (NAMCS) data from 20062010 to include all clinic-based office visits in the U.S. among persons ≥18 years of age with
a diagnosis of diabetes. Generalized linear models (binomial/logistic, negative binomial,
zero-truncated negative binomial) were used to assess the odds or incidence rates of ED/IP
admission, past number of annual visits, and physician time spent per case among those
involving DFUs, also controlling for age, sex, race, regional poverty and education level,
rural residence, geographic area, primary payer, chronic comorbid diseases, and year.
Results: Across the estimated 539.9 million ambulatory care cases involving diabetes
presenting from 2006-2010 in the U.S., 1.9 million had a DFU (0.4%), averaging 66.9±14.5
years of age, 64.5% male, 81.4% white, and 28.7% rural. Multivariable analyses indicated
DFUs were associated with an adjusted odds or incidence rate ratio of 4.6x higher risk for
ED/IP admission, 76.0% more annual clinic visits, and 53.0% longer physician time per visit
(p<0.05 for all); these were higher than a majority of comorbid diseases measured and
similar to or exceeding cancer, heart failure, or renal failure., Across DFU cases alone, those
residing in more impoverished areas had a 62.0% shorter physician visit time (p<0.05),
though no difference in the number of visits per year.
Conclusion: This investigation of 1.9 million ambulatory cases of DFUs in the U.S. indicates
markedly greater odds for emergency department referral or hospital admission, annual
number of outpatient visits, and physician time spent per visit., Outcomes relating to DFUs
exceeded or were similar to those of cancer, heart failure, or renal failure.
Funding: This research was not funded by any agency or organization.
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O7.2
RISK FACTORS FOR PROLONGED HOSPITALIZATION IN PATIENTS WITH DIABETIC
FOOT ULCER
Tania Tedjo, Diponegoro University, Semarang, Indonesia
Tjokorda Gde Dalem Pemayun, Diponegoro University, Semarang, Indonesia
Ridho Monotoc Naibaho, Diponegoro University, Semarang, Indonesia
Background: Indonesia is now on the 7th rank of country with largest diabetes population in
the world and predicted to become at the 5th rank in year 2025. Diabetic foot ulcer counts for
about 20% of all diabetic complications. Morbidity and mortality related to diabetic foot ulcer
in Indonesia is enormous.
AIM: Aim of the study is to figure out factors that have association with prolonged
hospitalization among patients with diabetic foot ulcer in our hospital.
Material and Method: A cross sectional study. Data taken from medical records of diabetic
foot ulcer patients admitted to Dr. Kariadi General Hospital, Central Java Province,
Indonesia. Period of admission: January-December 2013. Sixty five out of 142 medical
records were recorded for further analysis. Association between each variable (age, duration
of diabetes, onset of ulcer, albumin level, Hb level, HbA1c level, and ulcer severity) and
length of stay (LOS; cut off 3 weeks duration) was analyzed.
Results: More than half of subjects was female (55 4%) with 1:1 2 male to female ratio.
Most were 40-59 year of age (73 8%); mean of age 53 7±9 4 years. Sixty percent suffered
from diabetes <6 years; median duration of diabetes was 4 years (6 mo-20 yr). Onset of
ulcer mostly were 2 weeks-1 month before admission (64 6%); median onset was 21 days
(2-180 days). More than half of subjects had hypoalbuminemia with plasma albumin level <2
5 g/dL (50 8%); only 4 6% came with sufficient albumin level (>3 5 g/dL). Mean plasma
albumin level 2 5±0 6 g/dL. Anemia with Hb level <10 g% found in 35 3% subjects; mean
Hb level 9 9±1 9 g%. None was in a good glycaemic control; mean HbA1c level 11 5±2
5%. Most patients came with advanced stage of ulcer (49 2% Wagner 4); only minority with
simple ulcer (7 7% Wagner 1). Almost half ended with amputation in various degree (43 1%).
Mean LOS 18 5±10 7 days; 30 8% was ≥3 weeks. Albumin and Hb level were two variables
which statistically had association with prolonged hospitalization for ≥3 weeks (p= 0 030; p=
0 029 respectively).
Conclusion: Diabetic foot ulcer patients with hypoalbuminemia and anemia were predicted
to have prolonged hospitalization for ≥3 weeks. It was mainly due to postponement of wound
healing and also time consumption for albumin and PRC transfusion.
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Page 2 of 5
O7.3
The risk of hospital-acquired foot pressure ulcers in people with diabetes
Gerry Rayman, The Ipswich Hospital NHS Trust, Ipswich, United Kingdom
Christopher Kerry, The Ipswich Hospital NHS Trust, Ipswich, United Kingdom
Prashanth Vas, Kings College Hospital, London, United Kingdom
Rajesh Rajendran, The Ipswich Hospital NHS Trust, Ipswich, United Kingdom
Sanjeev Sharma, The Ipswich Hospital NHS Trust, Ipswich, United Kingdom
Anne Rayman, The Ipswich Hospital NHS Trust, Ipswich, United Kingdom
Background: Inpatients with diabetes are believed to be at greater risk of hospital acquired
pressure sores however to date there are no data on the extent of this increase.
Aims: To determine whether the diagnosis of diabetes confers an increased risk of hospital
acquired foot pressure sores/ulceration.
Method: From early 2008 our Trust mandated reporting of all Grade 2 or above pressure
ulcers using the ‘Serious Untoward Incident’ (SUI) reporting system. From this database,
numbers of hospital-acquired (after the first 24hrs) foot pressure ulcers between 01/10/2008
and 31/9/2010 were extracted and separated into groups with and without diabetes.
Results: During this period there were 223 and 61 hospital acquired foot ulcers in those
without and with diabetes. Based on admission rates this gives an ulceration rate of
3.64/1000 admissions for those without and 8.67/1000 for those with diabetes; a relative risk
ratio of 2.38 (CI- 1.79, 3.16); p<0.001. Since diabetes is associated with a longer stay the
relative risk was also determined per 1000 bed days; this was 0.62/1000 bed days for those
without and 0.98/1000 for those with diabetes; a relative risk ratio of 1.58 (1.19, 2.10);
p<0.001.
Conclusion: This study show that the diagnosis of diabetes confers a twofold increased risk
of hospital acquired foot lesions. This may be reduced by specifically targeting foot
protection to those at increased risk- i.e. those with neuropathy, vascular and renal disease
and those with previous ulceration.
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O7.4
Reduction in the incidence of hospital-acquired foot pressure ulcers in people with
diabetes
Gerry Rayman, The Ipswich Hospital NHS Trust, Ipswich, United Kingdom
Christopher Kerry, The Ipswich Hospital NHS Trust, Ipswich, United Kingdom
Prashanth Vas, Kings College Hospital, London, United Kingdom
Rajesh Rajendran, The Ipswich Hospital NHS Trust, Ipswich, United Kingdom
Sanjeev Sharma, The Ipswich Hospital NHS Trust, Ipswich, United Kingdom
Anne Rayman, The Ipswich Hospital NHS Trust, Ipswich, United Kingdom
Background: We previously reported a reduction in the frequency of hospital acquired foot
pressure ulcers, in inpatients with diabetes following introduction of an innovation to identify
those at increased risk- the Foot of the Bed form containing a risk identifier based on history
and a simple screening test for sensory loss- the Ipswich Touch Test (FOB & IpTT).
However, over the same period in England there was increased attention to prevention of
hospital acquired pressure ulcers at all body areas which could have explained the
reduction.
Aims: To compare the rates of foot pressure ulceration in inpatients with and without
diabetes before and after introducing the FOB & IpTT.,
Method: From 2008 our hospital mandated reporting of all pressure ulcers, grade 2 or
greater, from which we obtained the numbers of hospital-acquired foot pressure ulcers for
those with and without diabetes from 2yrs before and 3yrs after introducing the FOB & IpTT.
Numbers of admissions and total bed days for these groups were obtained from hospital
statistics.
Results: Foot ulcers/1000 admissions fell 44% from 3.64 to 2.04 (p<0.001) in those without
diabetes and 60% from 8.67 to 2.76 (p<0.001) in those with diabetes. The fall was
significantly greater in those with diabetes (p<0.02). Expressed per 1000 bed days, foot
ulcers fell 42% [0.62 to 0.36 (p<0.001)] in those without and 66% in those with diabetes
[0.98 to 0.33 (p<0.001)]. Again the reduction was significantly greater in those with diabetes
(p<0.02) and the risk was no longer different from the non-diabetic population.
Conclusion: Following the introduction of the FOB & IpTT there was a two-thirds reduction
in the rates of hospital acquired foot pressure ulcers in people with diabetes; significantly
greater than in those without diabetes. Indeed the excess risk associated with diabetes was
negated. These findings may have important implications for prevention of inpatient acquired
diabetic foot pressure ulcers in other hospitals.
www.diabeticfoot.nl
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O7.5
Lower limb amputation risk factors: long-term follow-up of the Seattle Diabetic Foot
Study cohort
Edward Boyko, University of Washington, Seattle, WA, United States
Amber Seelig, VA Puget Sound, Seattle, WA, United States
Jessie Ahroni, VA Puget Sound, Seattle, WA, United States
Aims: Little longitudinal research exists on the risk of diabetic lower limb amputation in
relation to limb-specific neurovascular measurements.
Methods: We prospectively followed 1453 diabetic veteran primary care patients without
foot ulcer and with 2852 lower limbs for the occurrence of a lower limb amputation. Study
enrollment began in 1991 with in-person follow-up in a specialized foot research clinic
continuing to 2002. Additional follow-up from 2002 through 2012 was performed using
national U.S. hospital discharge data to capture amputation occurrence. Each lower limb
underwent the following tests at baseline and repeatedly until 2002: ankle-arm index (ABI),
foot 5.07 monofilament insensitivity (MI), and dorsal foot transcutaneous oximetry (TcPO2).
Other characteristics assessed included diabetes features, past history of ulcer and
amputation, and other clinical and laboratory measurements. Cox regression was used to
estimate hazard ratios (HR) for amputation in each limb by limb-specific measurements and
other exposures. The HR for a continuous variable was calculated for a 1 standard deviation
increase.
Results: At baseline participants were 98% male with mean age 62 yrs, mean weight 98 kg,
and mean diabetes duration 15 yrs. Follow-up time ranged from <1 to 22 yrs, during which
time 104 amputations occurred (41 below the ankle), for an incidence of 6/1000 limb-yrs. In
univariate analysis, significant (p<0.05) amputation predictors were history of foot ulcer or
amputation; insulin use; MI; Charcot deformity; poor vision 20/70-20/190; blindness; low ABI;
low TcPO2; low serum albumin; low estimated glomerular filtration rate (eGFR); and high
HbA1c. Using a forward selection algorithm to generate an age-adjusted multivariable model
among men only, the following covariates significantly (p<0.05) and independently predicted
amputation risk: history of foot ulcer (HR 1.7, 95% CI 1.0-2.6) and amputation (4.3, 1.9-9.4),
MI (4.3, 2.5-7.4), insulin use (1.8, 1.1-3.0), poor vision (2.0, 1.1-3.8), blindness (2.4, 1.2-4.8),
ABI (0.7, 0.5-1.0), and eGFR (0.7, 0.6-0.9).
Conclusions: The risk of diabetic amputation is associated with not only limb neurovascular
function, but also insulin use, previous diabetes complications, poor vision, and renal
impairment.
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