Joint effects of obstructive sleep apnea and resistant hypertension on chronic heart failure: A cross-sectional study

Obstructive sleep apnea (OSA) and resistant hypertension (RHTN) are two major risk factors of chronic heart failure (CHF) and limited information is available about the joint effects of OSA and RHTN on CHF.

Baseline data of participants who had completed polysomnography were used in the current study. The relative excess risk due to interaction (RERI) and attributable proportion due to interaction (AP) were calculated, and RERI >0 or AP >0 indicates joint effect of OSA and RHTN on CHF is greater than the sum of estimated effects of OSA alone and RHTN alone. Due to significant interaction between coronary heart disease (CHD) and both OSA and RHTN, participants were stratified into with and without CHD subgroups.

Among 1157 participants, 33.1% had OSA. The prevalence of RHTN in OSA participants was 18.3%. The apnea-hypopnea index (AHI), pulse pressure and CHF were significantly associated with RHTN. In the CHD subgroup, participants with OSA and RHTN were associated with >3-fold increased odds of prevalent CHF. RERI was 2.66 and AP was 0.75. The odds of prevalent CHF with left ventricular ejection fraction (LVEF) ≥45% in participants with OSA+RHTN were >2-fold higher compared to those without, or with either OSA or RHTN, and RERI was 1.50 and AP was 0.72.

Presence of CHF, increased AHI and pulse pressure are independently associated with RHTN. OSA and RHTN have significant joint effects on CHF, especially in patients with concurrent CHD and preserved LVEF.