1. Institute for Clinical Diabetology, German Diabetes Center, Leibniz Center for Diabetes Research at Heinrich Heine University Düsseldorf, Düsseldorf, Germany;
2. Department of Epidemiology and Public Health, University College London, London, U.K.;
3. Department of Metabolic Diseases, University Hospital Düsseldorf, Heinrich Heine University Düsseldorf, Düsseldorf, Germany;
4. Steno Diabetes Center, Gentofte, Denmark;
5. Semmelweis University Faculty of Medicine, 1st Department of Medicine, Budapest, Hungary.