Effects of continuous positive airway pressure on blood pressure and daytime sleepiness in obstructive sleep apnea patients with coronary heart diseases under optimal medications

Abstract

Continuous positive airway pressure (CPAP) is an effective therapy for obstructive sleep apnea (OSA). However, for patients who already have OSA and coronary heart diseases (CHD) with optimal medications, whether CPAP can reduce the blood pressure (BP) is not clear. This is a controlled study to evaluate the effects of CPAP on BP in Chinese cohorts with CHD under optimal medications. Twenty-four patients with CHD and moderate to severe OSA were treated with CPAP and standard care for 1month. Twenty-four matched control patients were only treated with standard care alone. Baseline demographic data as well as sleep study data was recorded in all patients. Office blood pressure, heart rate, Epworth sleepiness scale (ESS) score, and quality of life (SF-36) of the two groups were compared after 1-month treatment. Compared with control group, CPAP treatment markedly reduced the morning diastolic BP (Δ -0.8 ± 6.0 vs. Δ -5.1 ± 6.5, respectively, P = 0.023) and improved ESS scores (Δ -0.5 ± 3.2 vs. Δ -5.2 ± 3.1, P < 0.001). In contrast, there were no significant changes in systolic BP (Δ -0.3 ± 7.3 vs. Δ -3.8 ± 11.8, P = 0.225), heart rate, and quality of life. CPAP treatment for 1month was associated with significant reduction in diastolic BP and improvement in ESS score. For patients with moderate to severe OSA and CHD under optimal medications, CPAP treatment leads to effective reduction in diastolic blood pressure and improvement in daytime sleepiness.