Temporal Trends in Incident Hospitalization for Diabetes-Related Foot Ulcer in Type 2 Diabetes: The Fremantle Diabetes Study
Research design and methods: Participants with type 2 diabetes from the community-based Fremantle Diabetes Study Phases I (FDS1; 1,296 participants, mean age 64.0 years, 48.6% males, recruited 1993-1996) and II (FDS2; 1,509 participants, mean age 65.4 years, 51.8% males, recruited 2008-2011) were followed from entry to first hospitalization for/with DFU, death or 5 years (whichever came first). Incident rate ratios (IRRs) and incident rate differences (IRDs) were calculated for FDS2 versus FDS1 overall and in 10-year age-groups. Cox proportional hazards modelling determined independent predictors of first DFU hospitalization in the combined cohort.
Results: Incident DFU hospitalization (95% CI) was 1.9 (0.9-3.3) /1,000 person-years in FDS1 during 5,879 person-years of follow-up, and 4.5 (3.0-6.4) /1,000 person-years in FDS2 during 6,915 person-years of follow-up. The crude IRR (95% CI) was 2.40 (1.17-5.28), P=0.013) and IRD 2.6 (0.7-4.5) /1,000 person-years (P=0.010). The highest incidence rate (IR) for any age-group was 23.6/1,000 person-years in FDS2 participants aged 31-40 years. Age at diabetes diagnosis (inverse), HbA1c, insulin use, height, ln(urinary albumin:creatinine), absence of any foot pulse, previous peripheral revascularization and peripheral sensory neuropathy (PSN) were independent predictors of incident hospitalization for/with DFU.
Conclusions: Incident DFU hospitalizations complicating type 2 diabetes increased between FDS Phases, especially in younger participants, and were more likely in those with PSN, peripheral arterial disease and suboptimal glycemic control at baseline.