Environmental risk factors for multiple sclerosis

iii Glossary iv Kort sammanfattning på svenska v Miljöfaktorers betydelse för multipel skleros v Background 1 Multiple sclerosis overview 1 Pathogenesis, clinical and para-clinical features 2 Sub-types 3 Establishing a multiple sclerosis diagnosis 3 Treatment 4 Epidemiology and risk factors 5 Background 5 Epstein-Barr virus 6 Smoking 7 Season of birth 8 Vitamin D 8 Vitamin A 9 The genes 10 Specific aims 11 Methods 12 Season of birth and multiple sclerosis in Sweden (Study I) 12 Study population and databases 12 Risk factors of multiple sclerosis (RoMS) and Gestational risk factors of multiple sclerosis (GRoMS) (Studies II–V) 12 Study population and sample databases 12 GRoMS case ascertainment 13 Other sources of data 14 Measurements and laboratory methods 15 Statistical methods 17 Ethical considerations 18 Results 20 Season of birth and multiple sclerosis in Sweden (Study I) 20 Risk factors of multiple sclerosis (RoMS, Studies II–V) 20 Clinical and demographic characteristics 20 Vitamin D (Study II) 20 Vitamin A (Study III) 21 C-reactive protein (Study III) 21 Smoking (Study IV) 21 Gestational samples, GRoMS (Studies II, III and cotinine data) 22