title: Family history and risk of subarachnoid hemorrhage: a case-control study in Nagoya, Japan.
abstract: OBJECTIVE
  We sought to examine the relation between a family history of subarachnoid hemorrhage (SAH) and the risk of SAH by using a case-control study.
  
  
  METHODS
  Case subjects consisted of a consecutive series of 195 patients with spontaneous SAH, aged 30 to 79 years, with aneurysms confirmed by angiography and/or CT scan. Hospital and community control subjects were identified and matched to each case by sex and age (+/-2 years). Multiple conditional logistic regression was used to calculate the odds ratio (OR) and 95% interval (CI) adjusted for potential confounders.
  
  
  RESULTS
  Having a family member with SAH was significantly associated with an increased risk of SAH (OR, 4.0, 95% CI, 2.0 to 8.0), after adjusting for potential confounders. The risk for a positive family history of SAH was similar for men and women and was inversely related to the SAH patient's age. A maternal positive SAH history (OR, 5.4; 95% CI, 1.8 to 16.0) posed a much greater risk than a paternal positive history (OR, 3.2, 95% CI, 1.1 to 13.4).
  
  
  CONCLUSIONS
  A positive family history of SAH was significantly and strongly associated with the risk of SAH. To prevent the onset of SAH at a younger age, much more attention should be given to individuals with any family member (first-degree relatives) suffering SAH episodes.
authors.affiliation: Department of Public Health, Aichi Prefectural College of Nursing and Health, Nagoya, Japan. okamoto@aichi-nurs.ac.jp
authors.forename: Kazushi
authors.initials: K
authors.lastname: Okamoto
authors.forename: Rokuro
authors.initials: R
authors.lastname: Horisawa
authors.forename: Takashi
authors.initials: T
authors.lastname: Kawamura
authors.forename: Akihiko
authors.initials: A
authors.lastname: Asai
authors.forename: Masataka
authors.initials: M
authors.lastname: Ogino
authors.forename: Takuya
authors.initials: T
authors.lastname: Takagi
authors.forename: Yoshiyuki
authors.initials: Y
authors.lastname: Ohno
mesh_terms: D000328:Adult; D017677:Age Distribution; D000368:Aged; D016022:Case-Control Studies; D002533:Cerebral Angiography; D015897:Comorbidity; D005260:Female; D006801:Humans; D002532:Intracranial Aneurysm / Q000175:diagnosis / Q000453:epidemiology / Q000235:genetics; D007564:Japan / Q000453:epidemiology; D008297:Male; D008875:Middle Aged; D016017:Odds Ratio; D012306:Risk; D018570:Risk Assessment; D012307:Risk Factors; D013345:Subarachnoid Hemorrhage / Q000175:diagnosis / Q000453:epidemiology* / Q000235:genetics*; D014057:Tomography, X-Ray Computed