title: Suboptimal awareness and control of hypertension increases the risk of subarachnoid hemorrhage in the community: results from the ACROSS.
abstract: BACKGROUND
  High blood pressure (BP) is a major risk factor for stroke and all of its pathological subtypes including subarachnoid hemorrhage (SAH). However, there is little evidence demonstrating whether failure to have regular BP measured could result in  underestimation of people at risk for SAH. Therefore, we aimed to estimate the effects of control of hypertension, diagnosing hypertension, and subsequent regular BP measurement on the risk of SAH in a population-based case-control setting.
  
  
  METHODS
  In 381 incident SAH cases  and 465 frequency-matched community SAH-free controls, data were collected on time of last BP measurement and ever diagnosed and treated hypertension.
  
  
  RESULTS
  After adjusting for covariates, the risks of SAH were both significantly higher among individuals who had never had their  BP measured (OR: 2·81, 95% CI: 1·27-6·22), who had their BP measured and been diagnosed with hypertension (treated: OR: 1·79, 95% CI: 1·22-2·62; untreated: OR: 1·82, 95% CI: 1·11-3·00), and who had been diagnosed  with hypertension but had not had their BP treated or measured in the last year (OR: 4·65, 95% CI: 2·09-10·32).
  
  
  CONCLUSIONS
  Compared to controls, cases of SAH are more likely to have never had their blood pressure measured and, among those who have been  diagnosed with hypertension, cases of SAH are less likely to have had their blood pressure measured in the past year. These results highlight the potential benefits of screening for hypertension and vigilantly controlling hypertension in reducing SAH rate at both population and individual  levels.
authors.affiliation: Royal Prince Alfred Hospital and the University of Sydney, Australia.
authors.forename: Ivy
authors.initials: I
authors.lastname: Shiue
authors.forename: Graeme J
authors.initials: GJ
authors.lastname: Hankey
authors.forename: Hisatomi
authors.initials: H
authors.lastname: Arima
authors.forename: Craig S
authors.initials: CS
authors.lastname: Anderson
mesh_terms: D000328:Adult; D000368:Aged; D016022:Case-Control Studies; D015897:Comorbidity / Q000639:trends; D005260:Female; D006266:Health Education / Q000379:methods / Q000639:trends*; D007722:Health Knowledge, Attitudes, Practice; D006801:Humans; D006973:Hypertension / Q000188:drug therapy / Q000453:epidemiology* / Q000517:prevention & control; D008297:Male; D008875:Middle Aged; D010353:Patient Education as Topic / Q000379:methods / Q000639:trends*; D012307:Risk Factors; D013345:Subarachnoid Hemorrhage / Q000453:epidemiology* / Q000517:prevention & control