2016 Articles

Masked Hypertension and Cardiovascular Disease Events in a Prospective Cohort of Blacks: The Jackson Heart Study

Booth III, John N.; Diaz, Keith; Seals, Samantha R.; Sims, Mario; Ravenell, Joseph; Muntner, Paul; Shimbo, Daichi

Masked hypertension, defined as non-elevated clinic blood pressure (BP) with elevated out-of-clinic BP, has been associated with increased cardiovascular disease (CVD) risk in Europeans and Asians. Few data are available on masked hypertension and CVD and mortality risk among African Americans (AAs).

We analyzed data from the Jackson Heart Study, a prospective cohort study of AAs. Analyses included participants with clinic-measured systolic/diastolic BP (SBP/DBP)<140/90mmHg who completed ambulatory BP monitoring (ABPM) following the baseline exam in 2000–2004 (n=738). Masked daytime (10:00am–8:00pm) hypertension was defined as mean ambulatory SBP/DBP≥135/85mmHg. Masked nighttime (midnight-6:00am) hypertension was defined as mean ambulatory SBP/DBP≥120/70mmHg. Masked 24-hour hypertension was defined as mean SBP/DBP≥130/80mmHg. CVD events (nonfatal/fatal stroke, nonfatal myocardial infarction or fatal coronary heart disease) and deaths identified through December 2010 were adjudicated. Any masked hypertension (masked daytime, nighttime or 24-hour hypertension) was present in 52.2% of participants; 28.2%, 48.2% and 31.7% had masked daytime, nighttime and 24-hour hypertension, respectively. There were 51 CVD events and 44 deaths over a median follow-up of 8.2 and 8.5 years, respectively. CVD rates per 1,000 person-years (95% CI) in participants with and without any masked hypertension were 13.5 (9.9–18.4) and 3.9 (2.2–7.1), respectively. The multivariable adjusted hazard ratio (95% CI) for CVD was 2.49 (1.26–4.93) for any masked hypertension and 2.86 (1.59–5.13), 2.35 (1.23–4.50) and 2.52 (1.39–4.58) for masked daytime, nighttime and 24-hour hypertension, respectively. Masked hypertension was not associated with all-cause mortality.

Masked hypertension is common and associated with increased risk for CVD events in AAs.