Diabetes-related lower-extremity amputation incidence and risk factors: a prospective seven-year study in Costa Rica

Abstract

Objective: To analyze the incidence and determinants of lower-extremity amputation (LEA) in people with diabetes in a low-income community in Costa Rica.

Methods: Data on LEA incidence were collected during a seven-year follow-up (2001-2007) in a diabetes patient cohort (n = 572). Risk factors were analyzed using the Cox proportional hazards regression model and baseline variables from the year 2000 (socio- demographic characteristics, comorbidity, metabolic control, treatment, and chronic microvascular complications).

Results: LEA incidence was 6.02 per 1 000 person-years (8.65 in men and 4.50 in women). Known risk factors (sex, years of diabetes, elevated glycated hemoglobin [HbA1c], retinopathy, insulin therapy, and prior amputation) were highly significant.

Conclusions: Those most likely to undergo LEA among Costa Rican diabetic patients were men with 10 or more years of diabetes and average HbA1c > 8% who used insulin and had diabetic retinopathy. Patients on insulin therapy were at greatest risk, especially those with a previous amputation. Diabetic patients with the above-mentioned profile should be considered to be at very high risk of LEA and followed closely by the health care system.