title: Home blood pressure variability as cardiovascular risk factor in the population of Ohasama.
abstract: Blood pressure variability based on office measurement predicts outcome in selected patients. We explored whether novel indices of blood pressure variability derived from the self-measured home blood pressure predicted outcome in a general population. We monitored mortality and stroke in 2421 Ohasama residents (Iwate Prefecture, Japan). At enrollment (1988-1995), participants (mean age, 58.6 years; 60.9% women; 27.1% treated) measured their blood pressure at home, using an oscillometric device. In multivariable-adjusted Cox models, we assessed the independent predictive value of the within-subject mean systolic blood pressure (SBP) and corresponding variability as estimated by variability independent of the mean, difference between maximum and minimum blood pressure, and average real variability. Over 12.0 years (median), 412 participants died, 139 of cardiovascular causes, and 223 had a stroke. In models including morning SBP, variability independent of the mean and average real variability (median, 26 readings) predicted total and cardiovascular mortality in all of the participants (P≤0.044); variability independent of the mean predicted cardiovascular mortality in treated (P=0.014) but not in untreated (P=0.23) participants; and morning maximum and minimum blood pressure did not predict any end point (P≥0.085). In models already including evening SBP, only variability independent of the mean predicted cardiovascular mortality in all and in untreated participants (P≤0.046). The R(2) statistics, a measure for the incremental risk explained by adding blood pressure variability to models already including SBP and covariables, ranged from <0.01% to 0.88%. In a general population, new indices of blood pressure variability derived from home blood pressure did not incrementally predict outcome over and beyond mean SBP.
authors.affiliation: Studies Coordinating Center, Division of Hypertension and Cardiovascular Rehabilitation, Department of Cardiovascular Diseases, University of Leuven, Leuven, Belgium.
authors.forename: Kei
authors.initials: K
authors.lastname: Asayama
authors.forename: Masahiro
authors.initials: M
authors.lastname: Kikuya
authors.forename: Rudolph
authors.initials: R
authors.lastname: Schutte
authors.forename: Lutgarde
authors.initials: L
authors.lastname: Thijs
authors.forename: Miki
authors.initials: M
authors.lastname: Hosaka
authors.forename: Michihiro
authors.initials: M
authors.lastname: Satoh
authors.forename: Azusa
authors.initials: A
authors.lastname: Hara
authors.forename: Taku
authors.initials: T
authors.lastname: Obara
authors.forename: Ryusuke
authors.initials: R
authors.lastname: Inoue
authors.forename: Hirohito
authors.initials: H
authors.lastname: Metoki
authors.forename: Takuo
authors.initials: T
authors.lastname: Hirose
authors.forename: Takayoshi
authors.initials: T
authors.lastname: Ohkubo
authors.forename: Jan A
authors.initials: JA
authors.lastname: Staessen
authors.forename: Yutaka
authors.initials: Y
authors.lastname: Imai
mesh_terms: D000328:Adult; D000368:Aged; D001794:Blood Pressure / Q000502:physiology*; D018660:Blood Pressure Monitoring, Ambulatory; D002318:Cardiovascular Diseases / Q000175:diagnosis / Q000453:epidemiology* / Q000401:mortality; D002940:Circadian Rhythm / Q000502:physiology; D005260:Female; D006801:Humans; D006973:Hypertension / Q000175:diagnosis / Q000453:epidemiology* / Q000401:mortality; D007564:Japan / Q000453:epidemiology; D008297:Male; D008875:Middle Aged; D011379:Prognosis; D018570:Risk Assessment; D012307:Risk Factors