Sleep-disordered breathing and chronic atrial fibrillation

BackgroundLittle has been known about the prevalence of sleep apnea in patients with atrial fibrillation (AF). Studies have suggested that the prevalence of AF is increasing in patients with sleep-disordered breathing. We hypothesize that the prevalence of OSA is higher in chronic persistent and permanent AF patients than a sub-sample of the general population without this arrhythmic disorder.ObjectiveEvaluate the frequency of Obstructive Sleep Apnea in a sample of chronic AF compared to a sub-sample of the general population.MethodsFifty-two chronic AF patients aged (60.5 ± 9.5, 33 males) and 32 control (aged 57.3 ± 9.6, 15 males). All subjects were evaluated by a staff cardiologist for the presence of medical conditions and were referred for polysomnography. The differences between groups were analyzed by ANOVA for continuous variables, and by the Chi-square test for dichotomous variables. Statistical significance was established by α = 0.05.ResultsThere were no differences in age, gender, BMI, sedentarism, presence of hypertension, type 2 diabetes mellitus, abdominal circumference, systolic and diastolic blood pressure, and sleepiness scoring between groups. Despite similar BMI, AF patients had a higher neck circumference compared to control group (39.9 cm versus 37.7 cm, p = 0.01) and the AF group showed higher percentage time of stage 1 NREM sleep (6.4% versus 3.9%, p = 0.03).Considering a cut-off value for AHI ⩾ 10 per hour of sleep, the AF group had a higher frequency of OSA compared to the control group (81.6% versus 60%, p = 0.03). All the oxygen saturation parameters were significantly worse in the AF group, which had lower SaO2 nadir (81.9% versus 85.3%, p = 0.01) and mean SaO2 (93.4% versus 94.3%, p = 0.02), and a longer period of time below 90% (26.4 min versus 6.7 min, p = 0.05).ConclusionSleep-disordered breathing is more frequent in chronic persistent and permanent AF patients than in age-matched community dwelling subjects.