Affiliation: | 1. Department of Neurology, Haukeland University Hospital, , Bergen, Norway;2. Department of Clinical Medicine, University of Bergen, , Bergen, Norway;3. Department of Neurology, Oslo University Hospital, Rikshospitalet, , Oslo, Norway;4. Centre for Clinical Research, Haukeland University Hospital, , Bergen, Norway;5. Lifestyle Epidemiology Research Group, Department of Public Health and Primary Health Care, University of Bergen, , Bergen, Norway |