Cardiovascular Autonomic Function in Patients with OSA

Objectives:Prospectively investigate the cardiovascular autonomic function in patients with obstructive sleep apnea (OSA) and examine the relationship with OSA severity, since impaired cardiovascular autonomic response is independently associated with cardio- and cerebro-vascular disease.Methods:Ninety-one subjects with symptoms of sleep-disordered breathing who underwent full-night polysomnography were recruited. Standard autonomic parameters which include heart rate response to deep breathing, Valsalva ratio, baroreflex sensitivity (BRS), and heart rate variability were obtained for further analysis and correlated to severity of OSA.Results:Seventy-three patients with OSA (apnea/hypopnea index, AHI ≥5/h) and 18 simple snore patients (AHI <5) as normal control were compared in this study. BRS was the only parameter with significant difference among the 2 groups (3.6 ± 1.2 in simple snore and 2.8 ± 1.4 in OSA patients, P = .03). Further association analysis revealed significant correlation between BRS and...