1. Department of Gastroenterology and Hepatology, University of Groningen, University Medical Center Groningen , Hanzeplein 1, 9713 GZ Groningen , the Netherlands
2. The Henry D. Janowitz Division of Gastroenterology, Department of Medicine, Icahn School of Medicine at Mount Sinai , New York, NY 10029 , USA
3. Department of Pathology and Medical Biology, University of Groningen, University Medical Center Groningen , Hanzeplein 1, 9713 GZ Groningen , the Netherlands
4. Department of Internal Medicine, Division of Endocrinology, University of Groningen, University Medical Center Groningen , Hanzeplein 1, 9713 GZ Groningen , the Netherlands
5. Department of Epidemiology, University of Groningen, University Medical Center Groningen , Hanzeplein 1, 9713 GZ Groningen , the Netherlands
6. Gentian AS , 1596 Moss , Norway
7. Department of Internal Medicine, Division of Nephrology, University of Groningen, University Medical Center Groningen , Hanzeplein 1, 9713 GZ Groningen , the Netherlands
8. Department of Internal Medicine, Division of Vascular Medicine, University of Groningen, University Medical Center Groningen , Hanzeplein 1, 9713 GZ Groningen , the Netherlands