1. Department I of Internal Medicine, Centre of Integrated Oncology Köln Bonn, University of Cologne, Cologne, Germany;
2. Cluster of Excellence on Cellular Stress Responses in Aging-associated Diseases (CECAD Cologne), Cologne, Germany;
3. Department III for Internal Medicine, University of Ulm, Ulm, Germany;
4. IIIrd Medical Department, Paracelsus Medical University Salzburg, Salzburg, Austria;
5. Department II for Internal Medicine, University Schleswig-Holstein, Campus Kiel, Germany; and
6. Institute of Medical Statistics and Epidemiology, Technical University, Munich, Germany