Temporal changes in predicted risk of type 2 diabetes in Germany: findings from the German Health Interview and Examination Surveys 1997–1999 and 2008–2011

OBJECTIVE: Over time, prevalence changes in individual diabetes risk factors have been observed for Germany and other European countries. We aimed to investigate the temporal change of a summary measure of type 2 diabetes risk in Germany. DESIGN: Comparison of data from two cross-sectional surveys that are about 12 years apart. SETTING: Two nationwide health examination surveys representative for the non-institutionalised population aged 18–79 years in Germany. PARTICIPANTS: The study included participants without diagnosed diabetes from the national health examination surveys in 1997–1999 (n=6457) and 2008–2011 (n=6095). OUTCOME MEASURES: Predicted 5-year type 2 diabetes risk was calculated using the German Diabetes Risk Score (GDRS), which considers information on age, anthropometry, lifestyle factors, hypertension and family history of diabetes. RESULTS: Between the two survey periods, the overall age- and sex-standardised predicted 5-year risk of type 2 diabetes decreased by 27% from 1.5% (95% CI 1.4% to 1.6%) to 1.1% (1.0% to 1.2%). The decrease in red meat intake and waist circumference had the highest impact on the overall decrease in diabetes risk. In stratified analyses, diabetes risk decreased among both sexes and within strata of age and body mass index. Diabetes risk also decreased among highly educated persons, but remained unchanged among persons with a middle or low educational level. CONCLUSIONS: Monitoring type 2 diabetes risk by a summary measure such as the GDRS could essentially contribute to interpret the dynamics in diabetes epidemiology.