Prevalence of Sleep-Disordered Breathing-Related Symptoms in Patients with Chronic Heart Failure and Reduced Ejection Fraction

Abstract

BackgroundSleep-disordered breathing (SDB) is highly prevalent in patients with chronic heart failure (CHF) and is associated with a poor prognosis. Data on SDB-related symptoms and vigilance impairment in patients with CHF and SDB are rare. Thus, the objective of the present study was to assess a wide spectrum of SDB-related symptoms and objective vigilance testing in patients with CHF with and without SDB. MethodsPatients with CHF (n = 222; average age, 62 years; left ventricular ejection fraction [LVEF], 34%) underwent polysomnography regardless of the presence or absence of SDB-related symptoms. Patients were stratified into those with no SDB (apnea-hypopnea index [AHI] < 15 episodes/h), moderate SDB (AHI ≥ 15 to < 30 episodes/h), and severe SDB (AHI ≥ 30 episodes/h). A standardized institutional questionnaire assessing a wide spectrum of SDB-related symptoms was applied. A subset of patients underwent objective vigilance testing (Quatember Maly, 100 stimuli within 25 minutes). ResultsDaytime fatigue (no SDB, moderate SDB, and severe SDB: 53%, 69%, and 80%, respectively; P = 0.005), unintentional sleep (9%, 15%, and 32%, respectively; P = 0.004), and xerostomia (52%, 49%, and 70%, respectively; P = 0.018), as well as an impaired objective vigilance test result (mean reaction time, 0.516, 0.497, and 0.579 ms, respectively; P < 0.001) occurred more frequently with increasing severity of SDB. Seventy-eight percent of patients with CHF and SDB had at least 3 SDB-related symptoms. In a linear multivariable regression model, the frequency of daytime fatigue (P = 0.014), unintentional sleep (P = 0.001), xerostomia (P = 0.016), and mean reaction time (P = 0.001) were independently associated with increasing AHI independent of age, body mass index, New York Heart Association functional class, and LVEF. ConclusionsThe majority of patients with CHF and SDB have several potential SDB-related symptoms and objective impairment of vigilance as potential treatment targets.