Abstract P2052: Differential Association of Measures of Adiposity With 24-Hour Ambulatory Blood Pressure Control in Adults on Antihypertensive Monotherapy

Abstract

Background: Regional measures of adipose distribution, such as visceral adiposity and waist circumference, are more strongly associated with metabolic activity of adipose tissue and longitudinal cardiovascular risk than broader metrics, such as body mass index (BMI) and total fat mass. Little is known about the differential relationship of BMI, waist circumference, visceral adiposity, and total fat mass with degree of blood pressure (BP) control on 24-hour ambulatory BP monitoring (ABPM) in adults with hypertension (HTN). Methods: We performed 24-hour ABPM in adults recruited from primary care clinics with a diagnosis of HTN on a stable dose of a single antihypertensive agent. Dual x-ray absorptiometry (DXA) was performed to determine visceral adiposity and total fat mass (indexed by height). Results: Of the 97 participants, mean age was 56 (+/- 13) years, with 56 (58%) women, 46 (47%) black, 28 (29%) with diabetes, and 13 (13%) smokers. Mean BMI was 31.7 (+/- 7.2) kg/m 2 and mean waist circumference was 104 (+/- 17) cm. Mean 24-hour systolic BP (SBP) was 135 (+/- 13) mmHg, mean 24-hour SBP average real variability (ARV) was 13 (+/- 3), 47 (48%) were non-dippers, 26 (27%) had masked HTN, and 21 (22%) had uncontrolled HTN. After adjusting for age, sex, race, and antihypertensive class, the highest quartiles of waist circumference and visceral adiposity were associated with higher 24-hour mean SBP (waist circumference β = 9.5, 95% CI 1.9-17.2; visceral adiposity β = 8.6, 95% CI 0.5-16.8) and SBP ARV (waist circumference β = 2.8, 95% CI 1.0 to 4.6; visceral adiposity β = 2.9, 95% CI 1.1 to 4.7) compared to the lowest quartiles; BMI and total fat mass were not associated with these ABPM parameters. Individuals in the highest quartile of visceral adiposity had a 6.3-fold greater odds (95% CI 1.2-33.1) of masked HTN compared to the lowest quartile; no other adiposity measures were associated with masked HTN. Conclusions: Elevated visceral adiposity is associated with high 24-hour SBP and SBP variability in individuals with HTN. Unlike other measures of adiposity, higher visceral adiposity is strongly linked with masked hypertension. Measurement of visceral adiposity may help to identify those individuals who would benefit most from 24-hour ABPM to screen for masked hypertension.