title: Prognostic value of reading-to-reading blood pressure variability over 24 hours in 8938 subjects from 11 populations.
abstract: In previous studies, of which several were underpowered, the relation between cardiovascular outcome and blood pressure (BP) variability was inconsistent. We followed health outcomes in 8938 subjects (mean age: 53.0 years; 46.8% women) randomly recruited from 11 populations. At baseline, we assessed BP variability from the SD and average real variability in 24-hour ambulatory BP recordings. We computed standardized hazard ratios (HRs) while stratifying by cohort and adjusting for 24-hour BP and other risk factors. Over 11.3 years (median), 1242 deaths (487 cardiovascular) occurred, and 1049, 577, 421, and 457 participants experienced a fatal or nonfatal cardiovascular, cardiac, or coronary event or a stroke. Higher diastolic average real variability in 24-hour ambulatory BP recordings predicted (P<or=0.03) total (HR: 1.14) and cardiovascular (HR: 1.21) mortality and all types of fatal combined with nonfatal end points (HR: >or=1.07) with the exception of cardiac and coronary events (HR: <or=1.02; P>or=0.58). Higher systolic average real variability in 24-hour ambulatory BP recordings predicted (P<0.05) total (HR: 1.11) and cardiovascular (HR: 1.16) mortality and all fatal combined with nonfatal end points (HR: >or=1.07), with the exception of cardiac and coronary events (HR: <or=1.03; P>or=0.54). SD predicted only total and cardiovascular mortality. While accounting for the 24-hour BP level, average real variability in 24-hour ambulatory BP recordings added <1% to the prediction of a cardiovascular event. Sensitivity analyses considering ethnicity, sex, age, previous cardiovascular disease, antihypertensive treatment, number of BP readings per recording, or the night:day BP ratio were confirmatory. In conclusion, in a large population cohort, which provided sufficient statistical power, BP variability assessed from 24-hour ambulatory recordings did not contribute much to risk stratification over and beyond 24-hour BP.
authors.affiliation: Department of Clinical Physiology, Faculty of Health Sciences, Hvidovre University Hospital, Research Center for Prevention and Health, Copenhagen, Denmark.
authors.forename: Tine W
authors.initials: TW
authors.lastname: Hansen
authors.forename: Lutgarde
authors.initials: L
authors.lastname: Thijs
authors.forename: Yan
authors.initials: Y
authors.lastname: Li
authors.forename: José
authors.initials: J
authors.lastname: Boggia
authors.forename: Masahiro
authors.initials: M
authors.lastname: Kikuya
authors.forename: Kristina
authors.initials: K
authors.lastname: Björklund-Bodegård
authors.forename: Tom
authors.initials: T
authors.lastname: Richart
authors.forename: Takayoshi
authors.initials: T
authors.lastname: Ohkubo
authors.forename: Jørgen
authors.initials: J
authors.lastname: Jeppesen
authors.forename: Christian
authors.initials: C
authors.lastname: Torp-Pedersen
authors.forename: Eamon
authors.initials: E
authors.lastname: Dolan
authors.forename: Tatiana
authors.initials: T
authors.lastname: Kuznetsova
authors.forename: Katarzyna
authors.initials: K
authors.lastname: Stolarz-Skrzypek
authors.forename: Valérie
authors.initials: V
authors.lastname: Tikhonoff
authors.forename: Sofia
authors.initials: S
authors.lastname: Malyutina
authors.forename: Edoardo
authors.initials: E
authors.lastname: Casiglia
authors.forename: Yuri
authors.initials: Y
authors.lastname: Nikitin
authors.forename: Lars
authors.initials: L
authors.lastname: Lind
authors.forename: Edgardo
authors.initials: E
authors.lastname: Sandoya
authors.forename: Kalina
authors.initials: K
authors.lastname: Kawecka-Jaszcz
authors.forename: Yutaka
authors.initials: Y
authors.lastname: Imai
authors.forename: Jiguang
authors.initials: J
authors.lastname: Wang
authors.forename: Hans
authors.initials: H
authors.lastname: Ibsen
authors.forename: Eoin
authors.initials: E
authors.lastname: O'Brien
authors.forename: Jan A
authors.initials: JA
authors.lastname: Staessen
mesh_terms: D001794:Blood Pressure / Q000502:physiology*; D018660:Blood Pressure Monitoring, Ambulatory; D002318:Cardiovascular Diseases / Q000453:epidemiology* / Q000503:physiopathology; D002940:Circadian Rhythm / Q000502:physiology*; D016208:Databases, Factual; D005260:Female; D006801:Humans; D015994:Incidence; D008297:Male; D008875:Middle Aged; D011379:Prognosis; D016016:Proportional Hazards Models; D012307:Risk Factors; D011795:Surveys and Questionnaires