1. Department of Neurology, Umeå University Hospital, Umea, Sweden
2. Department of Public Health and Clinical Medicine, Epidemiology and Public Health Sciences, Umeå University, Umea, Sweden
3. Department of Transfusion Medicine, Umeå University Hospital, Umea, Sweden
4. Department of Public Health and Clinical Medicine, Nutritional Research, Umea University, Umea, Sweden