2 Section Endocrinology and Diabetology, University Obesity Centre Hamburg, University Hospital Hamburg-Eppendorf, Germany.
3 University Hospital Carl Gustav Carus at the TU Dresden, Department of Metabolic Vascular Medicine, Dresden and German Center for Diabetes Research (DZD e. V.), Neuherberg, Germany.
4 Medical Clinic IV, University Hospital Tübingen, Germany.
5 Centre for Internal Medicine I, Marienhospital, Stuttgart, Germany.
6 Medical Clinic I, Berufsgenossenschaftliches University Hospital Bergmannsheil, Bochum, Germany.
7 Medical Clinic I, University Hospital, Aachen, Germany.
8 Diabetes Center Bochum-Hattingen, St.-Josef-Hospital, Ruhr-University, Bochum, Germany.
9 Diabetological Practice, Jena, Germany.
10 Department of Internal Medicine - Gastroenterology, Diabetology/Endocrinology and Nutritional Medicine, St. Josefkrankenhaus Heidelberg GmbH, Heidelberg, Germany.