Independent association of obstructive sleep apnea with left ventricular geometry and systolic function in resistant hypertension: the RESIST-POL study

Abstract

Objective: We investigated the impact of obstructive sleep apnea (OSA) and night blood pressure (BP) on left ventricular geometry and systolic function in patients with resistant hypertension (RHTN).

Methods and results: Data from 155 patients with RHTN were analyzed. All patients underwent biochemical evaluations, ambulatory blood pressure monitoring (ABPM), and polysomnography. Left ventricular mass index (LVMI), relative wall thickness (RWT), left ventricular ejection fraction (LVEF), midwall fractional shortening (mwFS) and global longitudinal strain (GLS) were measured. Patients were divided into four groups based on the presence of metabolic syndrome (MS) and OSA: group 1: OSA(-), MS(-) [n = 42]; group 2: OSA(+), MS(-) [n = 14]; group 3: OSA(-), MS(+) [n = 46]; and group 4: OSA(+), MS(+) [n = 53]. In group 3 and 4 concentric geometry was present in 53.2% and 79.6% respectively (P = 0.004). There were no differences in LVEF between groups. Group 3 and 4 had lower mwFS as compared with group 1 (16.40 ± 1.9 and 15.38 ± 2.2 vs 17.44 ± 1.9; P < 0.049 and P < 0.0001 respectively). Group 4 had significantly lower GLS as compared with group 1 (-12.64 ± 3.3 vs -15.59 ± 4.0; P < 0.001). In the multivariable analysis, factors independently associated with concentric geometry were age, nighttime SBP (OR -1.04; 95%Cl 1.019-1.082; P < 0.0001) and OSA (OR -3.97; 95%Cl 1.835-8.590; P < 0.0001). In the other multivariable analysis, factors independently associated with GLS were OSA (beta = 0.279; P = 0.001), and nighttime DBP (beta = 0.168; P = 0.048) whereas factors independently associated with mwFS were age, gender, nighttime SBP, concentric geometry, and metabolic syndrome.

Conclusions: In patients with true RHTN without diabetes concentric geometry and systolic dysfunction are independently associated with moderate and severe OSA and nighttime BP levels.

Keywords: Echocardiography; Hypertension; Left ventricular geometry; Left ventricular systolic function; Obstructive sleep apnea; Polysomnography.