Determinants of decreasing major amputation rates in Germany

We analysed a potential association between the decrease in major amputations in Germany and the number of doctors, prescribed podologic foot care (PFC) and antidiabetic drugs, and performed percutaneous endoluminal angioplasties (PTA).

Data of all lower limb major amputations between 2007 and 2011, the cases hospitalised with an additional diagnosis of diabetes mellitus, and the numbers of PTAs, and the number of doctors in private practices and in hospitals were obtained from the Federal Statistical Office. Furthermore, the number of PFC treatments and prescribed antidiabetics for each of the five years were derived from the federal report of the statutory health insurance.

Within the 5 year time period, major amputations decreased by 19.0%, from 17,846 in 2007 to 14,463 in 2011. There is an inverse relation between the number of major amputations and the increasing number of prescribed PFC, of doctors working in hospital and of below-the-knee PTA in the multiple Poisson regression analysis. The number of prescribed antidiabetics and that of all PTA showed a positive relation. In the multiple linear regression analysis with the dependent variable ratio of amputations and the cases hospitalised with an additional diagnosis of diabetes mellitus, only numbers of prescribed PFC and below-the-knee PTA still showed an inverse relation that reached a level of significance.

While substantial improvements in patients care by doctors, endovascular interventions, prescriptions of PFC and antidiabetic drugs are under discussion to reduce major amputation rates, in this approach including comprehensive data from Germany, only prescriptions of PFC and the number of below-the-knee PTA had an independent and significant impact on the reduction of major amputations. It has to be pointed out that such a statistical association does not prove any causality.