title: Association of cholesterol with stroke risk varies in stroke subtypes and patient subgroups.
abstract: OBJECTIVE
  To perform a health maintenance organization-based case-control study to evaluate the association of total and high density lipoprotein (HDL) cholesterol with the risk of stroke subtypes and in patient subgroups.
  
  
  METHODS
  Cases had a confirmed incident ischemic stroke (n = 1,242) or hemorrhagic stroke (n = 313). Controls (n = 6,455) were identified in a companion myocardial infarction study. Risk of stroke was modeled using logistic regression.
  
  
  RESULTS
  The highest total cholesterol quintile was associated with an increased risk of ischemic stroke compared to the lowest quintile (OR = 1.6, 95% CI 1.3 to 2.0) with the strongest subtype associations for atherosclerotic stroke (OR = 3.2) and lacunar stroke (OR = 2.4). The highest HDL cholesterol quintile was associated with a decreased risk of ischemic stroke compared to the lowest quintile (OR = 0.8, CI 0.6 to 1.0). Subgroup analyses suggested that the total cholesterol association was more important for patients < 66 years of age and those with HDL < 50 mg/dL; the HDL association was more important for patients without diabetes or atrial fibrillation. The second through fourth total cholesterol quintiles were associated with a decreased risk of hemorrhagic stroke compared to the lowest quintile (OR = 0.7, CI 0.5 to 1.0).
  
  
  CONCLUSIONS
  Higher total and lower HDL cholesterol levels were associated with increased risk of ischemic stroke, especially certain stroke subtypes and patient subgroups. The lowest levels of total cholesterol were associated with an increased risk of all hemorrhagic strokes.
authors.affiliation: Department of Neurology, University of Washington, Seattle, USA. tirsch@u.washington.edu
authors.forename: D L
authors.initials: DL
authors.lastname: Tirschwell
authors.forename: N L
authors.initials: NL
authors.lastname: Smith
authors.forename: S R
authors.initials: SR
authors.lastname: Heckbert
authors.forename: R N
authors.initials: RN
authors.lastname: Lemaitre
authors.forename: W T
authors.initials: WT
authors.lastname: Longstreth
authors.forename: B M
authors.initials: BM
authors.lastname: Psaty
mesh_terms: D000328:Adult; D000368:Aged; D001161:Arteriosclerosis / Q000097:blood / Q000453:epidemiology; D001281:Atrial Fibrillation / Q000097:blood / Q000453:epidemiology; D002545:Brain Ischemia / Q000097:blood / Q000453:epidemiology; D016022:Case-Control Studies; D002543:Cerebral Hemorrhage / Q000097:blood / Q000453:epidemiology; D002784:Cholesterol / Q000097:blood*; D008076:Cholesterol, HDL / Q000097:blood; D015897:Comorbidity; D003920:Diabetes Mellitus / Q000097:blood / Q000453:epidemiology; D005260:Female; D006801:Humans; D006937:Hypercholesterolemia / Q000097:blood / Q000453:epidemiology*; D006973:Hypertension / Q000097:blood / Q000453:epidemiology; D016015:Logistic Models; D008297:Male; D008875:Middle Aged; D017698:Postmenopause / Q000097:blood; D012306:Risk; D020521:Stroke / Q000097:blood / Q000145:classification / Q000453:epidemiology*; D013345:Subarachnoid Hemorrhage / Q000097:blood / Q000453:epidemiology
chemical_list: D008076:Cholesterol, HDL; D002784:Cholesterol