title: Duration, frequency, recency, and type of migraine and the risk of ischaemic stroke in women of childbearing age.
abstract: BACKGROUND
  Migraine is recognised increasingly as a risk factor for ischaemic stroke in women of childbearing age. Migraine with aura poses a higher risk than migraine without aura.
  
  
  OBJECTIVE
  To investigate further the effect of duration, frequency, recency, and type of migraine on the risk of ischaemic stroke.
  
  
  METHODS
  Additional analyses of a previously reported multicentre case-control study of the relation between stroke and migraine in women aged 20-44 years.
  
  
  RESULTS
  Among 86 cases of ischaemic stroke and 214 controls, the adjusted risk of ischaemic stroke was significantly associated with: (1) migraine of more than 12 years duration, odds ratio (OR) 4.61 (1.27-16.8); (2) initial migraine with aura, OR 8.37 (2.33-30.1); (3) particularly if attacks were more frequent than 12 times per year, OR 10.4 (2.18-49.4). In no case did correction for oral contraception usage significantly alter these odds ratios. Increasing risk of ischaemic stroke was related to a change to increased frequency of headaches (trend p <or= 0.03).
  
  
  CONCLUSIONS
  These data support earlier reports of a relation between ischaemic stroke and migraine with aura. The risk seems particularly high in those whose initial migraine type involved aura occurring more than 12 times per year.
authors.affiliation: Department of Clinical Neurology, Radcliffe Infirmary, Oxford, UK.
authors.forename: M
authors.initials: M
authors.lastname: Donaghy
authors.forename: C L
authors.initials: CL
authors.lastname: Chang
authors.forename: N
authors.initials: N
authors.lastname: Poulter
mesh_terms: D000328:Adult; D016022:Case-Control Studies; D002544:Cerebral Infarction / Q000175:diagnosis / Q000453:epidemiology / Q000209:etiology*; D003278:Contraceptives, Oral, Hormonal / Q000008:administration & dosage / Q000009:adverse effects*; D003430:Cross-Sectional Studies; D005060:Europe; D005260:Female; D006801:Humans; D008881:Migraine Disorders / Q000150:complications* / Q000175:diagnosis / Q000453:epidemiology; D020325:Migraine with Aura / Q000150:complications* / Q000175:diagnosis / Q000453:epidemiology; D012306:Risk; D014944:World Health Organization
chemical_list: D003278:Contraceptives, Oral, Hormonal