Sex differences in masked hypertension: the Coronary Artery Risk Development in Young Adults study.

Abstract

To evaluate the association of sex with masked hypertension, defined by out-of-clinic hypertension based on ambulatory blood pressure monitoring (ABPM) among adults without hypertension based on blood pressure (BP) measured in the clinic, after adjusting for potential confounders. We evaluated sex differences in the prevalence of masked hypertension and the difference between awake, or alternatively 24-h, ambulatory BP and clinic BP using multivariable adjusted models among 658 participants who underwent 24-h ABPM and had clinic SBP/DBP less than 140/90 mmHg during the Year 30 Exam of the Coronary Artery Risk Development in Young Adults study. The mean age ± standard deviation (SD) of the participants was 54.8 ± 3.7 years, 58.4% were women, and 58.2% were black. The prevalence of any masked hypertension was 37.5% among women and 60.6% among men. In a model including adjustment for demographics, cardiovascular risk factors, antihypertensive medication, and clinic BP, the prevalence ratios (95% confidence intervals) comparing men versus women were 1.39 (1.18-1.63) for any masked hypertension, and 1.60 (1.28-1.99), 1.71 (1.36-2.15), and 1.40 (1.13-1.73) for masked awake, 24-h and asleep hypertension, respectively. In a fully adjusted model, the differences between mean awake ambulatory BP and clinic BP were 2.75 [standard error (SE) 0.92] mmHg higher for SBP and 3.61 (SE 0.58) mmHg higher for DBP among men compared with women. The prevalence of masked hypertension on ABPM was high in both men and women. Male sex was an independent predictor of masked hypertension.