1 Clinic for Thoracic and Cardiovascular Surgery, Herz- und Diabeteszentrum NRW, Ruhr University Bochum, Bad Oeynhausen, Germany. azittermann@hdz-nrw.de.
2 Department of Internal Medicine and Geriatrics, Bethel Clinic (EvKB), Bielefeld, Germany.
3 Division of Endocrinology and Diabetology, Department of Internal Medicine, Medical University of Graz, Graz, Austria.