Short-Term but not Long-Term Blood Pressure Variability Is a Predictor of Adverse Cardiovascular Outcomes in Young Untreated Hypertensives

Abstract

Background: Whether blood pressure variability (BPV) measured with ambulatory monitoring (short-term BPV) or computed from office visits (long-term BPV) are related to each other and carry similar prognostic information is not well known. We investigated the independent determinants of short-term and long-term BPVs and their predictive capacity for the development of major adverse cardiovascular and renal events (MACEs) in a cohort of young hypertensive participants.

Methods: Long-term BPV was calculated as visit-to-visit SD and average real variability from office blood pressure (BP) measured during 7 visits, within 1 year. Short-term BPV was calculated as weighted 24-hour SD and coefficient of variation. Hazard ratios (HRs) for risk of MACE were computed from multivariable Cox regressions.

Results: 1,167 participants were examined; mean age was 33.1 ± 8.5 years. Variables independently associated with 24-hour systolic SD were 24-hour systolic BP, low physical activity, smoking, baseline office pulse pressure, systolic BP dipping, and diastolic white coat effect, while those associated with long-term BPV were mean systolic BP, age, female gender, and baseline office heart rate. During a median follow-up of 17.4 years 75 MACEs occurred. In Cox analysis only short-term BPV resulted a significant predictor of MACE (HR, 1.31 (1.07-1.59); P = 0.0086), while no index of long-term BPV was independently associated with outcome.

Conclusions: In young hypertensive subjects only short-term BPV resulted a significant predictor of MACE on top of traditional ambulatory BP monitoring parameters. Whether reduction of short-term BPV with therapy may reduce the cardiovascular risk independently from the effects on 24-hour BP is a matter for future research.

Keywords: blood pressure; cardiovascular; hypertension; risk; variability.