Abstract 4138663: Peak nocturnal home blood pressure as an early and strong novel risk factor for stroke: the practitioner-based nationwide J-HOP Nocturnal BP study

Background: Clinical implications of high peak nighttime home blood pressure (BP) are currently unknown. This analysis investigated the association between peak nighttime home systolic BP (SBP) and cardiovascular events in individuals with ≥1 cardiovascular risk factor. Methods: In the Japan Morning Surge-Home Blood Pressure (J-HOP) study, nighttime home BP was automatically measured three times every night for 14 days at baseline using a nighttime home BP monitoring device (HEM-5001, Omron Healthcare). Peak nighttime home SBP was defined as average of the highest three values over the 14-night measurement period. Occurrence of cardiovascular events (stroke, coronary artery disease, heart failure, aortic dissection) was determined over a mean 7.1 years’ follow-up. Results: This analysis included 2545 individuals (mean age 63.3±10.3 years, 49% male). After adjustment for covariates (including age, sex, and average office, morning, evening, and nighttime home SBP), stroke risk was significantly higher in individuals with peak nighttime home SBP in the highest (Q5, ≥149.0 mmHg) versus lowest quintile (Q1, <119.3 mmHg) (hazard ratio [HR] 4.24, 95% confidence interval [CI] 1.07–16.77; p=0.039 overall and 8.92, 1.49–53.43; p=0.017 in the subgroup with ≥6 nighttime home SBP measurements). This increased stroke risk remained significant after controlling for day-by-day average real variability of nighttime BP. The average peak nighttime home SBP cut-off value for predicting an increased risk of incident stroke was 136 mmHg. Conclusions: We propose exaggerated peak nighttime home SBP determined from ≥6 measurements as a novel risk factor for stroke, independent of conventional office and home BP values.