title: Major stressful life events in adulthood and risk of multiple sclerosis.
abstract: OBJECTIVE
  It is unclear whether psychological stress is associated with increased risk of multiple sclerosis (MS). We studied the association between major stressful life events and MS in a nationwide cohort study using death of a child or a spouse or marital dissolution as indicators of severe stress.
  
  
  METHODS
  We created two study cohorts based on all Danish men and women born 1950-1992. One cohort consisted of all persons who became parents between 1968 and 2010, and another cohort consisted of all persons who married between 1968 and 2010. Members of both cohorts were followed for MS between 1982 and 2010 using data from the National Multiple Sclerosis Registry. Associations between major stressful life events and risk of MS were evaluated by means of MS incidence rate ratios (RR) with 95% confidence interval (CI) obtained in Poisson regression analyses.
  
  
  RESULTS
  During approximately 30 million person-years of follow-up, bereaved parents experienced no unusual risk of MS compared with parents who did not lose a child (RR=1.12 (95% CI 0.89 to 1.38)). Likewise, neither divorced (RR=0.98 (95% CI 0.89 to 1.06)) nor widowed (RR=0.98 (95% CI 0.71 to 1.32) persons were at any unusual risk of MS compared with married persons of the same sex.
  
  
  CONCLUSIONS
  Our national cohort study provides little evidence for a causal association between major stressful life events (as exemplified by divorce or the loss of a child or a spouse) and subsequent MS risk.
authors.affiliation: Department of Epidemiology Research, Statens Serum Institut, Copenhagen, Denmark.
authors.forename: Nete Munk
authors.initials: NM
authors.lastname: Nielsen
authors.affiliation: Department of Epidemiology Research, Statens Serum Institut, Copenhagen, Denmark.
authors.forename: Peter
authors.initials: P
authors.lastname: Bager
authors.affiliation: Department of Epidemiology Research, Statens Serum Institut, Copenhagen, Denmark.
authors.forename: Jacob
authors.initials: J
authors.lastname: Simonsen
authors.affiliation: Department of Epidemiology Research, Statens Serum Institut, Copenhagen, Denmark.
authors.forename: Anders
authors.initials: A
authors.lastname: Hviid
authors.affiliation: The Danish Multiple Sclerosis Registry, Rigshospitalet, Copenhagen, Denmark Institute of Regional Health Research, University of Southern Denmark, Odense, Denmark Multiple Sclerosis Clinic of Southern Jutland (Sønderborg, Vejle, Esbjerg), Department of Neurology, Sønderborg, Denmark National Institute of Public Health, University of Southern Denmark, Copenhagen, Denmark.
authors.forename: Egon
authors.initials: E
authors.lastname: Stenager
authors.affiliation: Faculty of Health Sciences, Department of Public Health, University of Copenhagen, Copenhagen, Denmark.
authors.forename: Henrik
authors.initials: H
authors.lastname: Brønnum-Hansen
authors.affiliation: The Danish Multiple Sclerosis Registry, Rigshospitalet, Copenhagen, Denmark Department of Clinical Epidemiology, Clinical Institute, University of Aarhus, Aarhus, Denmark.
authors.forename: Nils
authors.initials: N
authors.lastname: Koch-Henriksen
authors.affiliation: Department of Epidemiology Research, Statens Serum Institut, Copenhagen, Denmark.
authors.forename: Morten
authors.initials: M
authors.lastname: Frisch
mesh_terms: D000328:Adult; D001601:Bereavement; D015331:Cohort Studies; D003718:Denmark / Q000453:epidemiology; D004243:Divorce; D005260:Female; D006801:Humans; D015994:Incidence; D008016:Life Change Events; D008297:Male; D009103:Multiple Sclerosis / Q000453:epidemiology* / Q000523:psychology*; D012042:Registries; D012044:Regression Analysis; D018570:Risk Assessment; D017805:Widowhood; D055815:Young Adult
keywords: EPIDEMIOLOGY; MULTIPLE SCLEROSIS; STRESS