Retrospective cohort study of long-term outcomes and prognostic factors for survival after lower extremity amputation in patients with diabetes

Aims: Lower extremity amputation (LEA) is a pivotal event for patients with diabetes. This study aimed to provide updated data on the outcomes and prognostic factors after LEA for patients with diabetes.

Methods: This retrospective cohort study included all LEAs (n = 1081) performed at Tampere University Hospital between February 2007 and September 2020. Overall survival (OS) and major amputation-free survival were evaluated.

Results: Index amputation level was below ankle in 65 % (n = 704) of patients, below knee in 14 % (n = 154) of patients, and above knee in 21 % (n = 223) of patients. In the whole population, OS was 75.8 % (CI 95 %: 73.3-78.3) at one year and 38.3 % (CI 95 %: 34.7-41.7) at five years. Higher age, peripheral artery disease (PAD), more proximal amputation level, and lower glomerular filtration rate (GFR) reduced OS. Multiple amputations and diagnosed dyslipidemia or hypertension associated with improved OS. Further, age, PAD, and GFR were identified as significant factors for major amputation free survival.

Conclusions: OS after LEA is poor. After major amputation, the risk for death is higher compared to minor amputation. Recurrent amputation is associated with improved OS. Further, ischemia and renal disease are significant factors for inferior OS.