Objective: To assess how visit-to-visit variability of SBP correlates with systemic atherosclerotic change and various prognoses.
Background: Visit-to-visit SBP variability correlates with cardiovascular events. However, the mechanisms underlying the impact of visit-to-visit SBP variability on prognoses are poorly understood.
Methods and results: A total of 485 patients with essential hypertension from the Non-Invasive Atherosclerotic Evaluation in Hypertension (NOAH) study cohort were included. We analyzed the correlation between visit-to-visit SBP variability and multiple clinical parameters. Next, we prospectively examined the correlation of SBP variability and frequency of cardiovascular disease (CVD) and total mortality. Patients with higher SBP variability exhibited significantly higher rates of statin use, as well as higher pulse wave velocity (PWV), left-ventricular mass index (LVMI), plaque score, and resistive index of the common carotid artery; these patients also exhibited lower estimated glomerular filtration rate. Kaplan–Meier analysis demonstrated that patients with higher SBP variability have a significantly higher incidence of CVD and mortality rate. The hazard ratio of SBP variability for incidence of CVD was greatly diminished after adjustment for intima–media thickness, plaque score, and resistive index, and was slightly diminished after adjustment for PWV and LVMI. Visit-to-visit SBP variability remained an independent risk factor for mortality after adjustment.
Conclusion: Visit-to-visit SBP variability correlates significantly with systemic atherosclerotic change, incidence of CVD, and mortality rate. Altered arterial functions, such as macrovascular atherosclerosis and vascular resistance, are responsible for the correlations between visit-to-visit SBP variability and incidence of CVD.
Department of Geriatric Medicine and Nephrology, Osaka University Graduate School of Medicine, Suita, Osaka, Japan
Correspondence to Mitsuru Ohishi, MD, PhD, Department of Geriatric Medicine and Nephrology, Osaka University Graduate School of Medicine, 2-2 Yamadaoka (B6), Suita, Osaka 565-0871, Japan. Tel: +81 6 6879 3852; fax: +81 6 6879 3859; e-mail: firstname.lastname@example.org
Abbreviations: ACC, associated clinical condition; BP, blood pressure; CAD, coronary artery disease; cfPWV, carotid-femoral pulse wave velocity; CT, computed tomography; CVD, cardiovascular disease; eGFR, estimated glomerular filtration rate; IMT, intima–media thickness; LVMI, left-ventricular mass index; PWV, pulse wave velocity
Received 13 November, 2012
Revised 6 February, 2013
Accepted 5 March, 2013