1. Department of Internal Medicine; University Medical Center Groningen; University of Groningen; Groningen The Netherlands
2. Department of Medical Physics; Mercer's Institute for Successful Ageing; St James's Hospital; Dublin Ireland
3. Department of Medical Gerontology; The Irish Longitudinal Study on Ageing (TILDA); Lincoln Gate; Trinity College; Dublin Ireland
4. Neurology Department; Beth Israel Deaconess Medical Center; Harvard Medical School; Boston MA USA
5. Department of Pulmonary Diseases; VU University Medical Center; Amsterdam The Netherlands
6. Heart Failure Research Center; Laboratory for Clinical Cardiovascular Physiology; Academic Medical Center; Amsterdam The Netherlands
7. Mercer's Institute for Successful Ageing; St James's Hospital; Dublin Ireland
8. Department of Internal Medicine; Academic Medical Center; Amsterdam The Netherlands