Visit-to-Visit Blood Pressure Variability and Mortality and Cardiovascular Outcomes among Older Adults: The Health, Aging, and Body Composition Study

Abstract

BACKGROUND Level of blood pressure (BP) is strongly associated with cardiovascular (CV) events and mortality. However, it is questionable whether mean BP can fully capture BP-related vascular risk. Increasing attention has been given to the value of visit-to-visit BP variability. METHODS We examined the association of visit-to-visit BP variability with mortality, incident myocardial infarction (MI), and incident stroke among 1,877 well-functioning elders in the Health, Aging, and Body Composition Study. We defined visit-to-visit diastolic BP (DBP) and systolic BP (SBP) variability as the root-mean-square error of person-specific linear regression of BP as a function of time. Alternatively, we counted the number of considerable BP increases and decreases (separately; 10 mm Hg for DBP and 20 mm Hg for SBP) between consecutive visits for each individual. RESULTS Over an average follow-up of 8.5 years, 623 deaths (207 from CV disease), 153 MIs, and 156 strokes occurred. The median visit-to-visit DBP and SBP variability was 4.96 mmHg and 8.53 mmHg, respectively. After multivariable adjustment, visit-to-visit DBP variability was related to higher all-cause (hazard ratio (HR) = 1.18 per 1 SD, 95% confidence interval (CI) = 1.01–1.37) and CV mortality (HR = 1.35, 95% CI = 1.05–1.73). Additionally, individuals having more considerable decreases of DBP (≥10mm Hg between 2 consecutive visits) had higher risk of all-cause (HR = 1.13, 95% CI = 0.99–1.28) and CV mortality (HR = 1.30, 95% CI = 1.05–1.61); considerable increases of SBP (≥20 mm Hg) were associated with higher risk of all-cause (HR = 1.18, 95% CI = 1.03–1.36) and CV mortality (HR = 1.37, 95% CI = 1.08–1.74). CONCLUSIONS Visit-to-visit DBP variability and considerable changes in DBP and SBP were risk factors for mortality in the elderly.