1. The Danish Multiple Sclerosis Registry, Department of Neurology, Copenhagen University Hospital—Rigshospitalet, Glostrup, Denmark
2. National Institute of Public Health, University of Southern Denmark, Copenhagen, Denmark
3. Department of Cardiology, Herlev-Gentofte University Hospital, Hellerup, Denmark
4. Danish Multiple Sclerosis Center, Department of Neurology, Copenhagen University Hospital—Rigshospitalet, Glostrup, Denmark