OBJECTIVE - To determine the incidence of foot ulcers in a large cohort of
patients with diabetes, the risk of developing serious complications after
diagnosis, and the attributable cost of care compared with that in patients
without foot ulcers.
RESEARCH DESIGN AND METHODS - Retrospective cohort study of patients with d
iabetes in a large staff-model health maintenance organization from 1993 to
1995. Patients with diabetes were identified by algorithm using administra
tive, laboratory and pharmacy records. The data were used to calculate inci
dence of foot ulcers, risk of osteomyelitis, amputation, and death after di
agnosis of foot ulcer, and attributable costs in foot ulcer patients compar
ed with patients without foot ulcers.
RESULTS - Among 8,905 patients identified with type 1 or type 2 diabetes, 5
14 developed a foot ulcer over 3 years of observation (cumulative incidence
5.8%). On or after the time of diagnosis, 77 (15%) patients developed oste
omyelitis and 80 (15.6%) required amputation. Survival at 3 years was 72% f
or the foot ulcer patients venus 87% for a group of age- and sex-matched di
abetic patients without foot ulcers (P < 0.001). The attributable cost for
a 40- to 65-year-old male with a new foot ulcer was $27,987 for the 2 years
after diagnosis.
CONCLUSIONS - The incidence of foot ulcers in this cohort of patients with
diabetes was nearly 2.0% per year. For those who developed ulcers, morbidit
y, mortality, and excess care costs were substantial compared with those fo
r patients without foot ulcers. The results appear to support the value of
foot-ulcer prevention programs for patients with diabetes.