title: Association between ambulatory systolic blood pressure during the day and asymptomatic intracranial arterial stenosis.
abstract: It is unclear at what time-window of the day blood pressure (BP) is most closely associated with cerebrovascular damage. In this cross-sectional study, we examined the strength of association between intracranial arterial stenosis (ICAS) and systolic BP (SBP) across different time-windows using 24-hour ambulatory BP monitoring in 757 consecutively recruited patients with hypertension. ICAS was diagnosed with computerized tomographic angiography in 127 (16.8%) patients, of whom 64 (50.4%) had stenosis ≥50% and 82 (64.6%) had ICAS in ≥2 vessels. Patients with ICAS (142 mm Hg), especially of multiple vessels (145 mm Hg), compared with patients without ICAS (126 mm Hg), had significantly (P<0.001) higher early morning (05:00-07:59 am) SBP. The differences remained significant (P≤0.015) after adjustment for cardiovascular risk factors and SBPs at other time-windows of the day. Multivariate regression analysis showed that consecutive 3-hourly mean SBPs during the day were significantly associated with ICAS (odds ratio for each 10-mm Hg increase, 1.28-1.38; P≤0.001). However, only mean SBP obtained between 05:00 am and 07:59 am remained significant for ICAS (odds ratio, 1.30; P=0.019) when all consecutive 3-hourly mean SBPs were forced into a single multivariate model. In conclusion, the present study showed a significant association between early morning SBP and asymptomatic ICAS in patients with hypertension after accounting for conventional cardiovascular risk factors. Our findings highlight the importance of morning SBP as a cardiovascular risk factor and should be validated in prospective studies.
authors.affiliation: Ruijin Hospital, Shanghai Institute of Hypertension, Shanghai Jiaotong University School of Medicine, 197 Ruijin 2nd Rd, Shanghai 200025, China. zhudingliang@sibs.ac.cn.
authors.forename: Chao-Ting
authors.initials: CT
authors.lastname: Chen
authors.forename: Yan
authors.initials: Y
authors.lastname: Li
authors.forename: Jin
authors.initials: J
authors.lastname: Zhang
authors.forename: Yan
authors.initials: Y
authors.lastname: Wang
authors.forename: Hua-Wei
authors.initials: HW
authors.lastname: Ling
authors.forename: Ke-Min
authors.initials: KM
authors.lastname: Chen
authors.forename: Ping-Jin
authors.initials: PJ
authors.lastname: Gao
authors.forename: Ding-Liang
authors.initials: DL
authors.lastname: Zhu
mesh_terms: D000368:Aged; D001794:Blood Pressure / Q000502:physiology; D018660:Blood Pressure Monitoring, Ambulatory; D001921:Brain / Q000098:blood supply; D002533:Cerebral Angiography; D002560:Cerebrovascular Circulation; D002940:Circadian Rhythm; D003251:Constriction, Pathologic; D003430:Cross-Sectional Studies; D005260:Female; D006801:Humans; D006973:Hypertension / Q000503:physiopathology*; D020765:Intracranial Arterial Diseases / Q000000981:diagnostic imaging / Q000503:physiopathology*; D008297:Male; D008875:Middle Aged; D013599:Systole; D014057:Tomography, X-Ray Computed
keywords: blood pressure monitoring, ambulatory; intracranial vascular disorders