Risk factors and mortality for amputations in the diabetic foot: a nationwide cohort study

Abstract

Objective: To investigate risk factors and mortality associated with major amputations in people with diabetic foot ulcers (DFUs), and to differentiate them from minor amputations. Study design: We conducted a nationwide, retrospective longitudinal study using cohort data from the Korean National Health Insurance Service (2002-2020), including people with DFUs who underwent lower extremity amputation. People were categorized into minor and major amputation groups. Comparative analyses were conducted using variables available from health insurance data. Results: Among 40,809 people with DFU-related amputations, the major amputation group showed a higher proportion of males, older age, and lower income. Revascularization procedures and use of top-tier antibiotics were more common in the major group. Comorbidities such as end-stage renal disease (ESRD), dementia, cerebrovascular disease, and ischemic heart disease were also more frequent (P < 0.001). The major group had higher mortality (73.9 % vs. 52.2 %) and shorter survival (986 vs. 1209 days). Dementia, ESRD, and prior major amputation had the highest adjusted hazard ratios for mortality. Conclusions: Major amputation in people with DFUs is associated with advanced age, vascular disease, comorbidities, and increased mortality. In contrast, minor amputation is linked to better survival. Limb-sparing approaches may improve long-term outcomes in this high-risk population.