1. Department of Cardiology, Oslo University Hospital Ullevål, Oslo University, Oslo, Norway
2. Unit of Biostatistics and Epidemiology, Oslo University Hospital, Oslo, Norway
3. Division of Renal Medicine, Department of Clinical Science, Intervention and Technology, Karolinska Institute, and Renal Medicine Karolinska University Hospital-Huddinge, Stockholm, Sweden
4. Department of Clinical Physiology, Karolinska Institute, Karolinska University Hospital-Huddinge, Stockholm, Sweden