1. Department of Internal Medicine, Leiden University Medical Center , Leiden , The Netherlands
2. Department of Internal Medicine, St Antonius Hospital , Nieuwegein , The Netherlands
3. Department of Nephrology and Hypertension, University Medical Center Utrecht , Utrecht , The Netherlands
4. Department of Clinical Epidemiology, Leiden University Medical Center , Leiden , The Netherlands
5. Department of Internal Medicine, Haga Hospital , The Hague , The Netherlands
6. Department of Gerontology and Geriatrics, Leiden University Medical Center , Leiden , The Netherlands