Association between obstructive sleep apnea and premature supraventricular contractions

Objective: The exact association between obstructive sleep apnea (OSA) and premature supraventricular contractions (PSVCs) has not been established. Methods: We prospectively performed polysomnography together with 24-hour Holter electrocardiography in 431 patients who were clinically suspected of having OSA and examined the association between OSA severity and PSVCs during wakefulness and sleep. The patients were classified into 4 groups according to the apnea-hypopnea index (AHI) quartiles (Q1 = patients with AHI <13.8, Q2 = those with 13.8 <= AHI <28.8, Q3 = those with 28.8 <= AHI <48.1, Q4 = those with AHI >= 48.1). Results: The number of PSVCs/hour during sleep differed significantly among the 4 groups, but the number of PSVCs/hour during wakefulness did not. The prevalence of PSVC >= 5/hour during sleep was significantly higher in Q4 (21.0%) than the other 3 groups (Q1, 9.0%; Q2, 8.0%; Q3, 6.0%; all p < 0.05 for Q4), but the prevalence of PSVC >= 5/hour during wakefulness did not differ among the 4 groups. A multivariate logistic regression analysis showed that the highest AHI quartile was significantly associated with PSVC >= 5/hour during sleep (odds ratio 3.04, 95% confidence interval 1.44-6.42, p = 0.004). Conclusions: Severe OSA can cause PSVCs during sleep, but its effect appears not to be strong. Further studies are needed to clarify the clinical significance of this small but significant increase in PSVCs during sleep in severe OSA patients. (C) 2013 Japanese College of Cardiology. Published by Elsevier Ltd. All rights reserved.