High Rate of Diabetes Lower Limb Amputation in Indigenous Australians: Is There a Causal Factor? (#325)
Background: Existing studies have identified presence of microvascular complications as contributing factor to poor diabetic foot ulcer (DFU) outcomes worldwide; however there is currently limited Australian evidence supporting this in Indigenous Australians. Furthermore data on the burden of limb amputation in Indigenous Australians with DFU have not been conclusively elucidated despite having 3-4 times at higher risk of diabetes. Objective: The aim of the study was to evaluate the prevalence of and risk factors for lower limb amputation in a specialist foot clinic populated by indigenous and non-indigenous diabetes patients. Methods: A retrospective case-controlled study was conducted, using clinical and biochemical profiles of diabetic foot patients attending the High Risk Foot Clinic at The Townsville Hospital Australia between 1st January 2011 and 31st December 2013. Results: The total study sample included 129 subjects, comprising 81 males, 48 females with M: F ratio of 2: 1. Twenty-three subjects were Indigenous Australians, representing 17.8% of the study population. The average age of the cohort was 63.4 years ± 14.1 years [CI 90.98-65.89]. Lower limb amputation was identified as a common and significant outcome (n=44), occurring in 34.1%, more commonly amongst the Indigenous Australians (56.5% vs 29.2%). Risk factors most closely associated with amputation included diabetic retinopathy (p<0.001, OR 4.4), past history of coronary artery bypass graft (CABG) surgery (p<0.01, OR 4.1), Charcot’s arthropathy (p<0.01, OR 2.9), and Indigenous ethnicity (p<0.01, OR 3.4). Conclusions: Lower limb amputation is a common outcome and linked to ethnicity amongst subjects with diabetic foot ulcer. Further research is needed to identify causal factors for lower limb amputation in Indigenous Australians presenting with DFU.