Abstract P170: Morning Surge and Cardiovascular Events in African Americans: The Jackson Heart Study

Abstract

Introduction: A larger sleep-trough morning surge, defined as the mean two-hour post-awakening blood pressure (BP) minus the lowest asleep BP, has been associated with cardiovascular disease (CVD) events in Asians and Europeans. High asleep BP in African Americans (AA) may preclude a morning surge and an association with CVD due to a smaller BP change upon awakening. Objective: Determine the association of morning surge with CVD events in AAs. Methods: We analyzed participants from the Jackson Heart Study, a community-based cohort of AAs, with a complete 24-hour ambulatory BP monitoring recording and self-report asleep and awake times at baseline in 2000-2004 (n=767). Participants were grouped into tertiles of sleep-trough morning surge, two-hour post-awakening BP and lowest sleep BP. CVD events (nonfatal/fatal stroke, nonfatal myocardial infarction or fatal coronary heart disease; n=61) through December 2012 were adjudicated. Results: Participants’ mean age was 59.2 years and 32.1% were male. Multivariable adjusted hazard ratios (95% CI) for CVD events associated with Tertile 2 and 3 versus Tertile 1 of morning systolic BP (SBP) surge were 1.45 (0.71 – 2.97) and 2.03 (0.98 – 4.23), respectively; of post-awakening SBP were 2.01 (0.81 – 4.99) and 4.41 (1.85 – 10.50), respectively; and of lowest asleep SBP were 1.55 (0.68 – 3.52) and 2.22 (0.96 – 5.14), respectively ( Table ). Also, there was a graded increasing risk for CVD associated with Tertile 2 and 3 versus Tertile 1 of post-awakening diastolic BP (DBP), but not morning DBP surge and lowest asleep DBP. Conclusion: Higher morning SBP surge, post-awakening SBP and lowest asleep SBP and DBP were associated increased CVD risk in AAs.