Factors associated with foot ulceration and amputation in adults on dialysis: a cross-sectional observational study

Background: Adults on dialysis are at increased risk of foot ulceration, which commonly precedes more serious lower limb complications, including amputation. Limited data exist regarding the prevalence and factors associated with foot disease in this population. Hence, this study set out to investigate factors associated with foot ulceration and amputation in a dialysis cohort. Methods: This study presents a cross-sectional analysis of baseline data from a multi-center prospective cohort study. We recruited 450 adults with end-stage renal disease on dialysis from multiple satellite and home-therapy dialysis units in Melbourne, Australia from January to December 2014. Data collection consisted of a participant interview, medical record review, health-status questionnaire and non-invasive foot examination. Logistic regression analyses were conducted to evaluate associations between screened variables and study outcomes. Results: Mean age was 67.5 (SD, 13.2) years, 64.7% were male, 94% were on hemodialysis, median dialysis duration was 36.9 (IQR, 16.6 to 70.1) months, and 50.2% had diabetes. There was a high prevalence of previous ulceration (21.6%) and amputation (10.2%), 10% had current foot ulceration, and 50% had neuropathy and/or peripheral arterial disease. Factors associated with foot ulceration were previous amputation (OR, 10.19), peripheral arterial disease (OR, 6.16) and serum albumin (OR, 0.87); whereas previous and/or current ulceration (OR, 167.24 and 7.49, respectively) and foot deformity (OR, 15.28) were associated with amputation. Conclusions: Dialysis patients have a high burden of lower limb complications. There are markedly higher risks of foot ulceration and/or amputation in those with previous and/or current ulceration, previous amputation, peripheral arterial disease, lower serum albumin, and foot deformity. Although not a major risk factor, diabetes in men was an important effect modifier for risk of ulceration.