title: China Stroke Primary Prevention Trial: Visit-to-Visit Systolic Blood Pressure Variability Is an Independent Predictor of Primary Stroke in Hypertensive Patients.
abstract: BACKGROUND
  The optimal range of blood pressure variability remains unclear. We aimed to stratify the degree of risk of stroke based on visit-to-visit systolic blood pressure (SBP) variability in a large Chinese hypertensive population in 32 communities.
  
  
  RESULTS
  We retrospectively analyzed the data of 20 702 hypertensive patients from the China Stroke Primary Prevention Trial. The participants were randomized into 2 treatment groups to receive either enalapril or enalapril plus folic acid. Their blood pressures were measured every 3 months. The outcome was the first stroke. Three parameters of SBP variability were calculated: standard deviation, coefficient of variation, and average real variability. The records of first 4, 6, 8, 10 and 12 visits at which SBP was measured were used to calculate SBP variability and to predict subsequent stroke risk in adjusted Cox regression models. After median follow-up of 4.5 years, 597 patients had experienced stroke. Visit-to-visit SBP variability was an independent predictor of subsequent stroke (eg, the hazard ratio for the highest quintile of average real variability [22.67-61.07 mm Hg] over 6 visits was 1.55, 95% CI 1.07-2.25,P=0.021), independent of mean SBP over the follow-up period. Its value was more predictive when more blood pressure records were used.
  
  
  CONCLUSIONS
  Visit-to-visit SBP variability is an independent predictor of primary stroke in Chinese hypertensive patients. This predictive value depends on the number of blood pressure measurements used to calculate variability but is independent of mean SBP.
  
  
  BACKGROUND
  URL: http://www.clinicaltrials.gov. Unique identifier: NCT00794885.
authors.affiliation: Department of Neurology, Peking University First Hospital, Beijing, China.
authors.forename: Xi
authors.initials: X
authors.lastname: Men
authors.affiliation: Department of Neurology, Peking University First Hospital, Beijing, China.
authors.forename: Wei
authors.initials: W
authors.lastname: Sun
authors.affiliation: Department of Cardiology, Peking University First Hospital, Beijing, China.
authors.forename: Fangfang
authors.initials: F
authors.lastname: Fan
authors.affiliation: Renal Division, National Clinical Research Study Center for Kidney Disease, State Key Laboratory for Organ Failure Research, Southern Medical University Nanfang Hospital, Guangzhou, China.
authors.forename: Min
authors.initials: M
authors.lastname: Zhao
authors.affiliation: Department of Cardiology, Second Affiliated Hospital of Nanchang University, Nanchang, China.
authors.forename: Xiao
authors.initials: X
authors.lastname: Huang
authors.affiliation: Renal Division, National Clinical Research Study Center for Kidney Disease, State Key Laboratory for Organ Failure Research, Southern Medical University Nanfang Hospital, Guangzhou, China.
authors.forename: Yu
authors.initials: Y
authors.lastname: Wang
authors.affiliation: Institute of Biomedicine, Anhui Medical University, Hefei, China.
authors.forename: Lishun
authors.initials: L
authors.lastname: Liu
authors.affiliation: Department of Neurology, Peking University First Hospital, Beijing, China.
authors.forename: Ran
authors.initials: R
authors.lastname: Liu
authors.affiliation: Department of Neurology, Peking University First Hospital, Beijing, China.
authors.forename: Weiping
authors.initials: W
authors.lastname: Sun
authors.affiliation: Department of Neurology, Peking University First Hospital, Beijing, China.
authors.forename: Qing
authors.initials: Q
authors.lastname: Peng
authors.affiliation: Renal Division, National Clinical Research Study Center for Kidney Disease, State Key Laboratory for Organ Failure Research, Southern Medical University Nanfang Hospital, Guangzhou, China.
authors.forename: Xianhui
authors.initials: X
authors.lastname: Qin
authors.affiliation: School of Health Administration, Anhui University, Hefei, China.
authors.forename: Genfu
authors.initials: G
authors.lastname: Tang
authors.affiliation: Department of Cardiology, Peking University First Hospital, Beijing, China.
authors.forename: Jianping
authors.initials: J
authors.lastname: Li
authors.affiliation: Department of Cardiology, Peking University First Hospital, Beijing, China.
authors.forename: Yan
authors.initials: Y
authors.lastname: Zhang
authors.affiliation: Department of Neurology, Guangdong Provincial Hospital of Chinese Medicine, Guangzhou, China.
authors.forename: Yefeng
authors.initials: Y
authors.lastname: Cai
authors.affiliation: Renal Division, National Clinical Research Study Center for Kidney Disease, State Key Laboratory for Organ Failure Research, Southern Medical University Nanfang Hospital, Guangzhou, China.
authors.forename: Fan Fan
authors.initials: FF
authors.lastname: Hou
authors.affiliation: Renal Division, National Clinical Research Study Center for Kidney Disease, State Key Laboratory for Organ Failure Research, Southern Medical University Nanfang Hospital, Guangzhou, China.
authors.forename: Binyan
authors.initials: B
authors.lastname: Wang
authors.affiliation: Renal Division, National Clinical Research Study Center for Kidney Disease, State Key Laboratory for Organ Failure Research, Southern Medical University Nanfang Hospital, Guangzhou, China.
authors.forename: Xiping
authors.initials: X
authors.lastname: Xu
authors.affiliation: Department of Cardiology, Second Affiliated Hospital of Nanchang University, Nanchang, China.
authors.forename: Xiaoshu
authors.initials: X
authors.lastname: Cheng
authors.affiliation: Department of Cardiology, Peking University People's Hospital, Beijing, China.
authors.forename: Ningling
authors.initials: N
authors.lastname: Sun
authors.affiliation: Department of Neurology, Peking University First Hospital, Beijing, China ynhuang@sina.com huoyong@263.net.cn.
authors.forename: Yining
authors.initials: Y
authors.lastname: Huang
authors.affiliation: Department of Cardiology, Peking University First Hospital, Beijing, China ynhuang@sina.com huoyong@263.net.cn.
authors.forename: Yong
authors.initials: Y
authors.lastname: Huo
mesh_terms: D000368:Aged; D000959:Antihypertensive Agents / Q000627:therapeutic use*; D001794:Blood Pressure / Q000187:drug effects*; D001795:Blood Pressure Determination / Q000379:methods; D002681:China / Q000453:epidemiology; D004311:Double-Blind Method; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D006973:Hypertension / Q000150:complications / Q000188:drug therapy* / Q000503:physiopathology; D008297:Male; D008875:Middle Aged; D009819:Office Visits; D011322:Primary Prevention / Q000379:methods*; D012189:Retrospective Studies; D012307:Risk Factors; D020521:Stroke / Q000453:epidemiology / Q000209:etiology / Q000517:prevention & control*; D013599:Systole; D013997:Time Factors
chemical_list: D000959:Antihypertensive Agents
keywords: hypertension; stroke; systolic blood pressure variability