1. Department of Internal Medicine, Division of General Internal Medicine, Section Geriatric Medicine, Maastricht University Medical Centre, P.O. Box 5800, NL-6202 AZ Maastricht, The Netherlands
2. Department of Internal Medicine, Division of Gastroenterology and Hepatology, Maastricht University Medical Centre, P.O. Box 5800, NL-6202 AZ Maastricht, The Netherlands
3. Diabetes Centre, Department of Vascular and Internal Medicine, Amsterdam University Medical Centre, P.O. Box 22660, NL-1100 DD Amsterdam, The Netherlands