1 Department of Internal Medicine A (Division of Cardiology, Angiology, Nephrology and Intensive Medical Care), University Hospital of the Brandenburg Medical School Theodor Fontane (MHB), Campus Ruppiner Kliniken, Fehrbelliner Strasse 38, D-16816 Neuruppin, Germany.
3 Institute of Biostatistics and Registry Research, Brandenburg Medical School Theodor Fontane (MHB), Fehrbelliner Strasse 38, D-16816 Neuruppin, Germany.
4 Department of Rehabilitation Medicine, Faculty of Health Sciences, University of Potsdam, Am Neuen Palais 10, D-14469 Potsdam, Germany.