title: Stroke risk in treated hypertension based on home blood pressure: the Ohasama study.
abstract: BACKGROUND
  Several observational studies have shown that treated hypertensives are characterized as having worse prognosis than nonhypertensives. However, there is little evidence based on home blood pressure (home BP) measurement. We compare the risk of stroke between untreated individuals and those taking antihypertensive medication based on home BP and casual-screening BP (casual BP) in the general population.
  
  
  METHODS
  The study included 1,690 untreated and 700 treated subjects aged >or=35 years. We measured home BP and casual BP at the beginning of the study. The risk of first stroke was examined by using the Cox proportional hazards model.
  
  
  RESULTS
  During 11.9 years of follow-up, we observed 242 first-time stroke cases. Treated subjects had significantly higher risk for stroke than untreated subjects based on home BP (relative hazard (RH) = 1.48) as well as on casual BP (RH = 1.78), adjusted for systolic BP values and characteristics. When subjects were classified into six categories based on BP (optimal, normal, high normal, and grade 1-3 hypertension), RHs in treated hypertensives linearly increased (trend P < 0.01) based on home BP. However, there was no consistent association for casual BP (trend P: not significant) in treated subjects. Stroke risk was linearly increased regardless of the BP information source in untreated subjects (home BP: trend P < 0.01, casual BP: trend P < 0.01).
  
  
  CONCLUSIONS
  The results suggest a strong association between elevated home BP and increased risk of stroke. Home BP is a better tool to assess stroke risk, especially in treated hypertensives.
authors.affiliation: Department of Clinical Pharmacology and Therapeutics, Tohoku University Graduate School of Pharmaceutical Sciences and Medicine, Sendai, Japan.
authors.forename: Daisaku
authors.initials: D
authors.lastname: Yasui
authors.forename: Kei
authors.initials: K
authors.lastname: Asayama
authors.forename: Takayoshi
authors.initials: T
authors.lastname: Ohkubo
authors.forename: Masahiro
authors.initials: M
authors.lastname: Kikuya
authors.forename: Atsuhiro
authors.initials: A
authors.lastname: Kanno
authors.forename: Azusa
authors.initials: A
authors.lastname: Hara
authors.forename: Takuo
authors.initials: T
authors.lastname: Hirose
authors.forename: Taku
authors.initials: T
authors.lastname: Obara
authors.forename: Hirohito
authors.initials: H
authors.lastname: Metoki
authors.forename: Ryusuke
authors.initials: R
authors.lastname: Inoue
authors.forename: Kazuhito
authors.initials: K
authors.lastname: Totsune
authors.forename: Haruhisa
authors.initials: H
authors.lastname: Hoshi
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Satoh
authors.forename: Yutaka
authors.initials: Y
authors.lastname: Imai
mesh_terms: D000368:Aged; D000959:Antihypertensive Agents / Q000627:therapeutic use; D001794:Blood Pressure / Q000502:physiology*; D018660:Blood Pressure Monitoring, Ambulatory; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D006973:Hypertension / Q000150:complications* / Q000188:drug therapy; D007564:Japan; D008297:Male; D008875:Middle Aged; D016016:Proportional Hazards Models; D012189:Retrospective Studies; D012307:Risk Factors; D020521:Stroke / Q000453:epidemiology*
chemical_list: D000959:Antihypertensive Agents