1. Institute for Clinical Diabetology; German Diabetes Center, Leibniz Center for Diabetes Research at Heinrich Heine University; Düsseldorf Germany
2. German Center for Diabetes Research, Partner; Düsseldorf Germany
3. Department of Endocrinology and Diabetology, Medical Faculty; Heinrich Heine University; Düsseldorf Germany
4. Institute for Biometry and Epidemiology; German Diabetes Center; Düsseldorf Germany