Results of a new methodology to compare diabetes related amputation rates in OECD countries

Background. Lower limb amputation represents a final event in the natural pathway of many subjects with diabetes. Limited information is available at the international level to monitor results on a global scale. Data collected by the OECD since 2000 has never been included in official publications, due to excess variability.MethodsIn 2014, volunteer experts of the OECD Health Care Quality Indicators Project and the EUBIROD network agreed to conduct a targeted research study on the revision of lower limb amputation rates in diabetes. The group carried out a review of the literature and data sources, followed by a case study on hospital data in Italy and a final discussion. The 2015 OECD data collection sheet requested specific information on numerators (minor and major amputations), denominators (diabetes prevalence and total population), and use of personal identifiers (admission vs patient-based indicator). Results were standardized by sex, age using the total population of countries contributing to each derived indicator. Generalized estimating equations were used to test the existence of temporal trends over the last 15 years.ResultsThe OECD data collection of amputation rates was successfully completed in June 2015 by 22 countries. Seventeen reported both major and minor amputations, twelve diabetes prevalence, seven used a personal identifier for the more accurate patient-based indicator. The average standardized rate of major amputations for 2013 was 110 (median 93, range 28–280) per 100,000 people with diabetes. Standardized rates of major amputations among people with diabetes significantly declined over the last 15 years (−5.2 per 100,000 per year, p<.0001). Variation across countries was substantially lower for the patient-based definition (CV = 42% vs 77%).ConclusionsThe OECD data collection 2015 allowed the calculation of different definitions of lower extremity amputations in diabetes, including the use of prevalent cases by sex and age bands. The results show a progressive decrease of major amputations among people with diabetes over the last 15 years. More stable estimates observed for patient-based definitions encourage further use of unique patient identifiers for future data collections.