1. Department of Clinical Chemistry and Laboratory Medicine Saarland University Hospital Homburg Germany
2. Agaplesion Markus Hospital, Medical Clinic II Frankfurt am Main Germany
3. Department of Internal Medicine IV–Nephrology and Hypertension Saarland University Hospital and Saarland University Faculty of Medicine Homburg Germany
4. Saarland University Medical Center, Internal Medicine III ‐ Cardiology, Angiology and Intensive Care Medicine Homburg Germany