title: Prognostic superiority of daytime ambulatory over conventional blood pressure in four populations: a meta-analysis of 7,030 individuals.
abstract: OBJECTIVE
  To investigate the multivariate-adjusted predictive value of systolic and diastolic blood pressures on conventional (CBP) and daytime (10-20 h) ambulatory (ABP) measurement.
  
  
  METHODS
  We randomly recruited 7,030 subjects (mean age 56.2 years; 44.8% women) from populations in Belgium, Denmark, Japan and Sweden. We constructed the International Database on Ambulatory blood pressure and Cardiovascular Outcomes.
  
  
  RESULTS
  During follow-up (median = 9.5 years), 932 subjects died. Neither CBP nor ABP predicted total mortality, of which 60.9% was due to noncardiovascular causes. The incidence of fatal combined with nonfatal cardiovascular events amounted to 863 (228 deaths, 326 strokes and 309 cardiac events). In multivariate-adjusted continuous analyses, both CBP and ABP predicted cardiovascular, cerebrovascular, cardiac and coronary events. However, in fully-adjusted models, including both CBP and ABP, CBP lost its predictive value (P >or= 0.052), whereas systolic and diastolic ABP retained their prognostic significance (P <or= 0.007) with the exception of diastolic ABP as predictor of cardiac and coronary events (P >or= 0.21). In adjusted categorical analyses, normotension was the referent group (CBP < 140/90 mmHg and ABP < 135/85 mmHg). Adjusted hazard ratios for all cardiovascular events were 1.22 [95% confidence interval (CI) = 0.96-1.53; P = 0.09] for white-coat hypertension (>or= 140/90 and < 135/85 mmHg); 1.62 (95% CI = 1.35-1.96; P < 0.0001) for masked hypertension (< 140/90 and >or= 135/85 mmHg); and 1.80 (95% CI = 1.59-2.03; P < 0.0001) for sustained hypertension (>or= 140/90 and >or= 135/85 mmHg).
  
  
  CONCLUSIONS
  ABP is superior to CBP in predicting cardiovascular events, but not total and noncardiovascular mortality. Cardiovascular risk gradually increases from normotension over white-coat and masked hypertension to sustained hypertension.
authors.affiliation: Research Center for Prevention and Health, Copenhagen, Denmark.
authors.forename: Tine W
authors.initials: TW
authors.lastname: Hansen
authors.forename: Masahiro
authors.initials: M
authors.lastname: Kikuya
authors.forename: Lutgarde
authors.initials: L
authors.lastname: Thijs
authors.forename: Kristina
authors.initials: K
authors.lastname: Björklund-Bodegård
authors.forename: Tatiana
authors.initials: T
authors.lastname: Kuznetsova
authors.forename: Takayoshi
authors.initials: T
authors.lastname: Ohkubo
authors.forename: Tom
authors.initials: T
authors.lastname: Richart
authors.forename: Christian
authors.initials: C
authors.lastname: Torp-Pedersen
authors.forename: Lars
authors.initials: L
authors.lastname: Lind
authors.forename: Jørgen
authors.initials: J
authors.lastname: Jeppesen
authors.forename: Hans
authors.initials: H
authors.lastname: Ibsen
authors.forename: Yutaka
authors.initials: Y
authors.lastname: Imai
authors.forename: Jan A
authors.initials: JA
authors.lastname: Staessen
mesh_terms: D018660:Blood Pressure Monitoring, Ambulatory / Q000379:methods*; D005260:Female; D006801:Humans; D006973:Hypertension / Q000503:physiopathology; D008297:Male; D015999:Multivariate Analysis; D011379:Prognosis