title: Meta-analysis of the relationship between multiple sclerosis and migraine.
abstract: BACKGROUND
  Studies investigating a proposed association between multiple sclerosis (MS) and migraine have produced conflicting results and a great range in the prevalence rate of migraine in MS patients. By meta-analysing all available data we aimed to establish an overall estimate of any association in order to more accurately inform clinicians and care-givers about a potential association between MS and migraine.
  
  
  METHODS
  Pubmed and EMBASE were searched to identify suitable studies. Studies were included if they were a case-control study or cohort study in which controls were not reported to have another neurological condition, were available in English, and specified migraine as a headache sub-type. The odds ratio (OR) of migraine in MS patients vs. controls was calculated using the inverse variance with random effects model in Review Manager 5.1.
  
  
  RESULTS
  Eight studies were selected for inclusion, yielding a total of 1864 MS patients and 261563 control subjects. We found a significant association between migraine and MS (OR = 2.60, 95% CI 1.12-6.04), although there was significant heterogeneity. Sensitivity analysis showed that migraine without aura was associated with MS OR = 2.29 (95% CI 1.14-4.58), with no significant heterogeneity.
  
  
  CONCLUSIONS
  MS patients are more than twice as likely to report migraine as controls. Care providers should be alerted to ask MS patients about migraine in order to treat it and potentially improve quality of life. Future work should further investigate the temporal relationship of this association and relationship to the clinical characteristics of MS.
authors.affiliation: Wellcome Trust Centre for Human Genetics, University of Oxford, Roosevelt Drive, Headington, Oxford, United Kingdom.
authors.forename: Julia
authors.initials: J
authors.lastname: Pakpoor
authors.forename: Adam E
authors.initials: AE
authors.lastname: Handel
authors.forename: Gavin
authors.initials: G
authors.lastname: Giovannoni
authors.forename: Ruth
authors.initials: R
authors.lastname: Dobson
authors.forename: Sreeram V
authors.initials: SV
authors.lastname: Ramagopalan
mesh_terms: D016022:Case-Control Studies; D006801:Humans; D008881:Migraine Disorders / Q000150:complications* / Q000453:epidemiology*; D009103:Multiple Sclerosis / Q000150:complications* / Q000453:epidemiology*; D016017:Odds Ratio; D015995:Prevalence; D012307:Risk Factors