title: Major risk factors for aneurysmal subarachnoid hemorrhage in the young are modifiable.
abstract: OBJECTIVE
  To identify risk factors for subarachnoid hemorrhage (SAH) and intracerebral hemorrhage, we designed a case-control study of men and women 18 to 49 years of age (the Hemorrhagic Stroke Project [HSP]). This report focuses on SAH.
  
  
  METHODS
  Patients were recruited from 44 hospitals in the United States. Cases with SAH must have had a ruptured aneurysm documented by angiography or surgery. Two controls, identified by random digit dialing and matched to each patient for age, sex, race, and telephone exchange, were sought for each case subject.
  
  
  RESULTS
  Between 1994 and 1999, 425 patients with SAH were enrolled in HSP, and 312 cases met the criteria for aneurysmal SAH. The present analyses also included 618 matched controls. Of the 312 cases, 66% were current cigarette smokers compared with 30% of controls (adjusted odds ratio [OR], 3.73; 95% CI, 2.67 to 5.21). Cocaine use within the previous 3-day period was reported by 3% of cases and no controls (bivariate exact OR, 24.97; 95% exact CI, 3.95 to infinity; adjusted estimate not calculable). Other independent risk factors in the multivariable model included hypertension (adjusted OR, 2.21; 95% CI, 1.48 to 3.29), low body mass index (OR, 1.59; 95% CI, 1.08 to 2.35), primary family history of hemorrhagic stroke (OR, 3.83; 95% CI, 1.73 to 8.46), caffeine in pharmaceutical products (OR, 2.48; 95% CI, 1.19 to 5.20), lower educational achievement (OR, 2.36; 95% CI, 1.44 to 3.87), and nicotine in pharmaceutical products (adjusted estimate not calculable).
  
  
  CONCLUSIONS
  Aneurysmal SAH may be largely a preventable disease among the young and middle-aged because several prevalent risk factors can be modified by medication (eg, hypertension) or behavioral change (eg, cigarette smoking, cocaine use). The association of caffeine and nicotine in pharmaceutical products and aneurysmal SAH warrants further study.
authors.affiliation: Department of Neurology, University of Cincinnati, College of Medicine, Cincinnati, Ohio 45267, USA. joseph.Broderick@uc.edu
authors.forename: Joseph P
authors.initials: JP
authors.lastname: Broderick
authors.forename: Catherine M
authors.initials: CM
authors.lastname: Viscoli
authors.forename: Thomas
authors.initials: T
authors.lastname: Brott
authors.forename: Walter N
authors.initials: WN
authors.lastname: Kernan
authors.forename: Lawrence M
authors.initials: LM
authors.lastname: Brass
authors.forename: Edward
authors.initials: E
authors.lastname: Feldmann
authors.forename: Lewis B
authors.initials: LB
authors.lastname: Morgenstern
authors.forename: Janet Lee
authors.initials: JL
authors.lastname: Wilterdink
authors.forename: Ralph I
authors.initials: RI
authors.lastname: Horwitz
mesh_terms: D000293:Adolescent; D000328:Adult; D017677:Age Distribution; D015992:Body Mass Index; D016022:Case-Control Studies; D019970:Cocaine-Related Disorders / Q000453:epidemiology; D015331:Cohort Studies; D015897:Comorbidity; D003299:Cooperative Behavior; D005260:Female; D006801:Humans; D006973:Hypertension / Q000453:epidemiology; D016015:Logistic Models; D008297:Male; D008875:Middle Aged; D016017:Odds Ratio; D010665:Phenylpropanolamine / Q000009:adverse effects; D012307:Risk Factors; D017678:Sex Distribution; D012907:Smoking / Q000453:epidemiology; D020521:Stroke / Q000453:epidemiology; D013345:Subarachnoid Hemorrhage / Q000139:chemically induced / Q000453:epidemiology*; D013851:Thinness; D014481:United States / Q000453:epidemiology
chemical_list: D010665:Phenylpropanolamine