The association between within-visit blood pressure variability and carotid artery atherosclerosis in general population.
OBJECTIVE
To determine whether within-visit blood pressure (BP) variability based on three measurements over minutes is associated with increased carotid intima-media thickness (IMT) and plaque in a general population.


METHODS
A cross-sectional survey was performed in 2007, and a total of 1222 Beijing community residents aged 50-79 years belonging to part of the Chinese Multi-Provincial Cohort Study (CMCS) were recruited in this study. BP was measured three times at 5-minute intervals during a single visit, and the maximum absolute difference (MAD) between any two readings of three measurements was used to indicate within-visit BP variability. Carotid IMT and plaque scanned by B-mode ultrasound were identified as the surrogate end points in the intermediate stage of atherosclerosis.


RESULTS
After adjustment for established cardiovascular risk factors, the odds ratio (OR) (95% confidence interval (CI)) for increased carotid IMT and internal carotid plaque associated with the highest within-visit diastolic BP (DBP) variability (MAD > mean + standard deviation (SD)) compared with participants in the lowest within-visit DBP variability (MAD ≤ mean -SD) was 4.92 (1.48-16.42) and 6.07 (1.31-28.10), respectively, in the normotensives (P = 0.01; P = 0.02). The OR (95% CI) for internal carotid plaque associated with the highest within-visit systolic BP (SBP) variability (MAD >mean +SD) compared with participants in the lowest within-visit SBP variability (MAD ≤ mean -SD) was 3.54 (1.26-10.00) in the hypertensives on antihypertensive therapy (P = 0.02).


CONCLUSIONS
Within-visit DBP variability was associated with increased carotid IMT and internal carotid plaque in the normotensive population, and within-visit SBP variability was associated with internal carotid plaque in hypertensive patients undergoing antihypertensive therapy.
Department of Epidemiology, Beijing An Zhen Hospital, Capital Medical University, Beijing Institute of Heart, Lung and Blood Vessel Diseases, Beijing, China.
Yan
Y
Li
Department of Epidemiology, Beijing An Zhen Hospital, Capital Medical University, Beijing Institute of Heart, Lung and Blood Vessel Diseases, Beijing, China.
Jing
J
Liu
Department of Epidemiology, Beijing An Zhen Hospital, Capital Medical University, Beijing Institute of Heart, Lung and Blood Vessel Diseases, Beijing, China.
Wei
W
Wang
Department of Epidemiology, Beijing An Zhen Hospital, Capital Medical University, Beijing Institute of Heart, Lung and Blood Vessel Diseases, Beijing, China.
Dong
D
Zhao
D000368:Aged; D001794:Blood Pressure; D002318:Cardiovascular Diseases / Q000517:prevention & control; D002339:Carotid Arteries / Q000000981:diagnostic imaging / Q000473:pathology*; D002340:Carotid Artery Diseases / Q000175:diagnosis / Q000453:epidemiology / Q000473:pathology* / Q000503:physiopathology*; D015331:Cohort Studies; D005260:Female; D006801:Humans; D006973:Hypertension / Q000503:physiopathology; D008297:Male; D008875:Middle Aged; D015995:Prevalence; D012307:Risk Factors; D017539:Tunica Intima / Q000473:pathology; D014463:Ultrasonography