Mendel Baba1, Wendy A Davis2, Timothy M E Davis3. 1. School of Medicine and Pharmacology, University of Western Australia, Fremantle Hospital, Fremantle, WA, Australia; Podiatric Medicine Unit, The University of Western Australia, Crawley, Perth, WA, Australia. 2. School of Medicine and Pharmacology, University of Western Australia, Fremantle Hospital, Fremantle, WA, Australia. 3. School of Medicine and Pharmacology, University of Western Australia, Fremantle Hospital, Fremantle, WA, Australia. Electronic address: tdavis@cyllene.uwa.edu.au.
Abstract
AIMS: To determine the prevalence and associates of foot ulcer, and the subsequent incidence and predictors of first-ever hospitalisation for this complication, in well-characterised community-based patients with type 2 diabetes. METHODS: Baseline foot ulceration was ascertained in 1296 patients (mean age 64 years, 48.6% male, median diabetes duration 4.0 years) recruited to the longitudinal Fremantle Diabetes Study between 1993 and 1996. Incident hospitalisation for foot ulceration was monitored through validated data linkage until end-December 2010. RESULTS: At baseline, 16 participants (1.2%) had a foot ulcer which was independently associated with intermittent claudication, peripheral sensory neuropathy (PSN) and diabetes duration (P≤0.01). The incidence of hospitalisation for this complication in those without prior/prevalent foot ulceration was 5.21 per 1000 patient-years. This rate and other published data suggest that 1 in 7-10 foot ulcers require hospitalisation. In a Cox proportional hazards model, intermittent claudication and PSN were significant independent predictors of time to admission with foot ulceration, in addition to retinopathy, cerebrovascular disease, HbA1c, alcohol consumption, renal impairment, peripheral arterial disease and pulse pressure (P≤0.038). CONCLUSIONS: These data confirm PSN as an important risk factor for foot ulceration but, in contrast to some other studies, peripheral arterial disease was also a major independent contributor. Associations between hospitalisation for foot ulcer and both retinopathy and raised pulse pressure suggest a role for local microvascular dysfunction, while alcohol may have non-neuropathic toxic effects on skin/subcutaneous structures. The multifactorial nature of foot ulceration complicating type 2 diabetes may have implications for its management.
AIMS: To determine the prevalence and associates of foot ulcer, and the subsequent incidence and predictors of first-ever hospitalisation for this complication, in well-characterised community-based patients with type 2 diabetes. METHODS: Baseline foot ulceration was ascertained in 1296 patients (mean age 64 years, 48.6% male, median diabetes duration 4.0 years) recruited to the longitudinal Fremantle Diabetes Study between 1993 and 1996. Incident hospitalisation for foot ulceration was monitored through validated data linkage until end-December 2010. RESULTS: At baseline, 16 participants (1.2%) had a foot ulcer which was independently associated with intermittent claudication, peripheral sensory neuropathy (PSN) and diabetes duration (P≤0.01). The incidence of hospitalisation for this complication in those without prior/prevalent foot ulceration was 5.21 per 1000 patient-years. This rate and other published data suggest that 1 in 7-10 foot ulcers require hospitalisation. In a Cox proportional hazards model, intermittent claudication and PSN were significant independent predictors of time to admission with foot ulceration, in addition to retinopathy, cerebrovascular disease, HbA1c, alcohol consumption, renal impairment, peripheral arterial disease and pulse pressure (P≤0.038). CONCLUSIONS: These data confirm PSN as an important risk factor for foot ulceration but, in contrast to some other studies, peripheral arterial disease was also a major independent contributor. Associations between hospitalisation for foot ulcer and both retinopathy and raised pulse pressure suggest a role for local microvascular dysfunction, while alcohol may have non-neuropathic toxic effects on skin/subcutaneous structures. The multifactorial nature of foot ulceration complicating type 2 diabetes may have implications for its management.