1. Department of Endocrinology and Diabetology, Medical Faculty and University Hospital Düsseldorf, Heinrich Heine University Düsseldorf , 40225 Düsseldorf , Germany
2. German Center for Diabetes Research, Partner Düsseldorf , 85764 München-Neuherberg , Germany
3. Institute for Clinical Diabetology, German Diabetes Center, Leibniz Center for Diabetes Research at Heinrich Heine University Düsseldorf , 40225 Düsseldorf , Germany
4. Institute for Biometrics and Epidemiology, German Diabetes Center, Leibniz Center for Diabetes Research at Heinrich Heine University Düsseldorf , 40225 Düsseldorf , Germany
5. Department of Internal Medicine, Gastroenterology and Diabetology, Niels Stensen Hospitals, Franziskus Hospital Harderberg , 49124 Georgsmarienhütte , Germany