title: Visit-to-visit blood pressure variability as a prognostic marker in patients with cardiovascular and cerebrovascular diseases--relationships and comparisons with vascular markers of atherosclerosis.
abstract: BACKGROUND
  Visit-to-visit blood pressure variability (BPV) is a simple surrogate marker for the development of atherosclerotic diseases, cardiovascular and all-cause mortality. Nevertheless, the relative prognostic value of BPV in comparison with other established vascular assessments remain uncertain.
  
  
  METHODS
  We prospectively followed-up 656 high-risk patients with diabetes or established cardiovascular or cerebrovascular diseases for the occurrence of major adverse cardiovascular events (MACEs). Baseline brachial endothelial function, carotid intima-media thickness (IMT) and plaque burden, ankle-brachial index and arterial stiffness were determined. Visit-to-visit BPV were recorded during a mean 18 ± 9 outpatient clinic visits.
  
  
  RESULTS
  After a mean 81 ± 12 month's follow-up, 123 patients (19%) developed MACEs. Patients who developed a MACE had significantly higher systolic BPV, more severe endothelial function, arterial stiffness and systemic atherosclerotic burden compared to patients who did not develop a MACE (all P<0.01). BPV significantly correlated with all of the vascular assessments (P<0.01). A high carotid IMT had the greatest prognostic value in predicting development of a MACE (area under receiver operating characteristic curve (AUC) 0.69 ± 0.03, P<0.01). A high BPV also had moderate prognostic value in prediction of MACE (AUC 0.65 ± 0.03, P<0.01). After adjustment of confounding factors, a high BPV remained a significant independent predictor of MACE (hazards ratio 1.67, 95% confidence interval 1.14-2.43, P<0.01).
  
  
  CONCLUSIONS
  Compared with established surrogate markers of atherosclerosis, visit-to-visit BPV provides similar prognostic information and may represent a new and simple marker for adverse outcomes in patients with vascular diseases.
authors.affiliation: Neurology Division, Department of Medicine, The University of Hong Kong, Hong Kong.
authors.forename: Kui Kai
authors.initials: KK
authors.lastname: Lau
authors.affiliation: Neurology Division, Department of Medicine, The University of Hong Kong, Hong Kong.
authors.forename: Yuen Kwun
authors.initials: YK
authors.lastname: Wong
authors.affiliation: Cardiology Division, Department of Medicine, The University of Hong Kong, Hong Kong.
authors.forename: Yap Hang
authors.initials: YH
authors.lastname: Chan
authors.affiliation: Neurology Division, Department of Medicine, The University of Hong Kong, Hong Kong.
authors.forename: Kay Cheong
authors.initials: KC
authors.lastname: Teo
authors.affiliation: Neurology Division, Department of Medicine, The University of Hong Kong, Hong Kong.
authors.forename: Koon Ho
authors.initials: KH
authors.lastname: Chan
authors.affiliation: Division of Rehabilitation Medicine, Department of Medicine, The University of Hong Kong, Hong Kong.
authors.forename: Leonard Sheung
authors.initials: LS
authors.lastname: Wai Li
authors.affiliation: Neurology Division, Department of Medicine, The University of Hong Kong, Hong Kong.
authors.forename: Raymond Tak Fai
authors.initials: RT
authors.lastname: Cheung
authors.affiliation: Cardiology Division, Department of Medicine, The University of Hong Kong, Hong Kong.
authors.forename: Chung Wah
authors.initials: CW
authors.lastname: Siu
authors.affiliation: Neurology Division, Department of Medicine, The University of Hong Kong, Hong Kong. Electronic address: slho@hku.hk.
authors.forename: Shu Leong
authors.initials: SL
authors.lastname: Ho
authors.affiliation: Cardiology Division, Department of Medicine, The University of Hong Kong, Hong Kong. Electronic address: hftse@hkucc.hku.hk.
authors.forename: Hung Fat
authors.initials: HF
authors.lastname: Tse
mesh_terms: D000368:Aged; D055109:Ankle Brachial Index; D019540:Area Under Curve; D050197:Atherosclerosis / Q000097:blood*; D015415:Biomarkers / Q000097:blood; D001794:Blood Pressure; D001795:Blood Pressure Determination; D001916:Brachial Artery / Q000503:physiopathology; D002318:Cardiovascular Diseases / Q000097:blood*; D059168:Carotid Intima-Media Thickness; D002561:Cerebrovascular Disorders / Q000097:blood*; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008297:Male; D008875:Middle Aged; D010045:Outpatients; D011379:Prognosis; D011446:Prospective Studies; D012307:Risk Factors; D013599:Systole; D016896:Treatment Outcome; D059289:Vascular Stiffness
chemical_list: D015415:Biomarkers
keywords: Blood pressure variability; Cardiovascular and cerebrovascular diseases; Vascular markers