title: White coat hypertension is more risky than prehypertension: important role of arterial wave reflections.
abstract: Arterial aging may link cardiovascular risk to white coat hypertension (WCH). The aims of the present study were to investigate the role of arterial aging in the white coat effect, defined as the difference between office and 24-hour ambulatory systolic blood pressures, and to compare WCH with prehypertension (PH) with respect to target organ damage and long-term cardiovascular mortality. A total of 1257 never-been-treated volunteer subjects from a community-based survey were studied. WCH and PH were defined by office and 24-hour ambulatory blood pressures. Left ventricular mass index, carotid intima-media thickness, estimated glomerular filtration rate, carotid-femoral pulse wave velocity, carotid augmentation index, amplitude of the reflection pressure wave, and 15-year cardiovascular mortality were determined. Subjects with WCH were significantly older and had greater body mass index, blood pressure values, intima-media thickness, carotid-femoral pulse wave velocity, augmentation index, amplitude of the backward pressure wave, and a lower estimated glomerular filtration rate than PH. Amplitude of the backward pressure wave was the most important independent correlate of the white coat effect in multivariate analysis (model r(2)=0.451; partial r(2)/model r(2)=90.5%). WCH had significantly greater cardiovascular mortality than PH (hazard ratio, 2.94; 95% confidence interval, 1.09-7.91), after accounting for age, sex, body mass index, smoking, fasting plasma glucose, and total cholesterol/high-density lipoprotein-cholesterol ratio. Further adjustment of the model for amplitude of the backward pressure wave eliminated the statistical significance of the WCH effect. In conclusion, the white coat effect is mainly caused by arterial aging. WCH carries higher risk for cardiovascular mortality than PH, probably via enhanced wave reflections that accompany arterial aging.
authors.affiliation: Department of Medicine, Taipei Veterans General Hospital, No. 201, Sec. 2, Shih-Pai Rd, Taipei, Taiwan.
authors.forename: Shih-Hsien
authors.initials: SH
authors.lastname: Sung
authors.forename: Hao-Min
authors.initials: HM
authors.lastname: Cheng
authors.forename: Kang-Ling
authors.initials: KL
authors.lastname: Wang
authors.forename: Wen-Chung
authors.initials: WC
authors.lastname: Yu
authors.forename: Shao-Yuan
authors.initials: SY
authors.lastname: Chuang
authors.forename: Chih-Tai
authors.initials: CT
authors.lastname: Ting
authors.forename: Edward G
authors.initials: EG
authors.lastname: Lakatta
authors.forename: Frank C P
authors.initials: FC
authors.lastname: Yin
authors.forename: Pesus
authors.initials: P
authors.lastname: Chou
authors.forename: Chen-Huan
authors.initials: CH
authors.lastname: Chen
mesh_terms: D001794:Blood Pressure / Q000502:physiology*; D018660:Blood Pressure Monitoring, Ambulatory; D002339:Carotid Arteries / Q000000981:diagnostic imaging / Q000503:physiopathology*; D059168:Carotid Intima-Media Thickness; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008297:Male; D008875:Middle Aged; D058246:Prehypertension / Q000175:diagnosis / Q000401:mortality / Q000503:physiopathology*; D063177:Pulse Wave Analysis / Q000379:methods; D012189:Retrospective Studies; D012307:Risk Factors; D012720:Severity of Illness Index; D015996:Survival Rate / Q000639:trends; D013624:Taiwan / Q000453:epidemiology; D059466:White Coat Hypertension / Q000175:diagnosis / Q000401:mortality / Q000503:physiopathology*
keywords: arterial aging; arterial wave reflections; cardiovascular mortality; prehypertension; white coat hypertension