1. Division of Internal Medicine, University Hospital of North Norway, Norway
2. Cardiovascular Research Group, The Arctic University of Norway, Norway
3. Department of Heart Disease, University Hospital of North Norway, Norway
4. Department of Community Medicine, The Arctic University of Norway, Norway
5. Department of Public Health and Nursing, Norwegian University of Science and Technology, Norway
6. Clinic for Heart Disease, St. Olavs University Hospital, Trondheim, Norway