Progression from Minor to Major Amputation in Patients with Diabetes and Peripheral Arterial Disease: Risk Factors...

Minor lower extremity (LE) amputation is commonly performed in patients with diabetes mellitus (DM) and peripheral arterial disease (PAD) as part of limb preservation strategies; however, progression to major amputation remains frequent in Mexico. We aim to study and characterize factors associated with progression to major amputations.

We completed a retrospective multicenter cohort study of adults with DM and PAD who underwent minor LE amputation between 2010 and 2025 at 5 tertiary referral centers in Mexico City. The primary outcome was progression to major amputation, reamputation, and mortality; and multivariable logistic regression was used to identify independent predictors.

Among 314 patients undergoing minor amputation, 184 (58.6%) progressed to major amputation, with a median time of 1 month (interquartile range (IQR [1-4]). Chronic limb-threatening ischemia (CLTI) was the strongest predictor of major amputation (adjusted odds ratio [aOR] 9.79, 95% confidence interval [CI], 3.45-27.77, P < 0.001). A proximal level of the index minor amputation was also independently associated with major limb loss (aOR 4.18, 95% CI, 1.56-11.19, P = 0.04). Chronic kidney disease (aOR 3.68, 95% CI, 1.47-9.20, P = 0.005) and smoking history (aOR 2.42, 95% CI, 1.14-5.13, P = 0.021) were additional significant risk factors. Prior revascularization was associated with a nonstatistically significant lower risk of progression (aOR 0.41, 95% CI, 0.16-1.02, P = 0.054).

Progression to major amputation after minor amputation is common and occurs early in patients with DM and PAD. CLTI, proximal minor amputation level, chronic kidney disease, and smoking identify patients at particularly high risk, underscoring the need for improved risk stratification and tailored limb management strategies.