Incidence of Lower-limb Amputations in the Diabetic Compared to the Non-diabetic Population. Findings from Nationwide Insurance Data, Germany, 2005-2007

Introduction: One major objective is to reduce the risk of lower limb amputation in diabetes mellitus. Nationwide data to incidences of amputations in the diabetic and non-diabetic populations in Germany as well as relative and attributable risks due to diabetes are lacking so far. Material and Methods: Using data of a nationwide statutory health insurance (1.6 million members), we assessed all first non-traumatic lower-limb amputations between 2005 and 2007. We estimated sex-age-specific and standardized incidences of amputations in the diabetic and non-diabetic populations, and relative and attributable risks due to diabetes. Results: Of all subjects with a first amputation in the study period 2005-2007 (n=994), 66% had diabetes, 76% were male, mean age (SD) was 67 (13) years. Incidences per 100000 person years (standardized to the 2004 German population) in the diabetic and the non-diabetic populations: 176.5 (95% confidence interval 156.0-196.9) and 20.0 (17.0-23.1) in men, and 76.9 (61.9-91.8) and 13.4 (10.7-16.2) in women. Standardized relative risks: 8.8 (7.3-10.7) in men and 5.7 (4.3-7.6) in women. Attributable risks among exposed: 0.89 and 0.83 and population attributable risks 0.59 and 0.40, each in men and women, respectively. Discussion: In our first German nationwide study, we found the relative risk of lower limb amputation in the diabetic compared to the nondiabetic to be lower than in earlier regional studies in Germany, supporting results of regional reductions of the excess amputation risk due to diabetes. A repetition of the study is warranted to further evaluate trends according to the St. Vincent goals.