Obstructive sleep apnea and self-reported functional impairment in revascularized patients with coronary artery disease in the RICCADSA trial

Abstract

Purpose: Daytime sleepiness, a frequent symptom of obstructive sleep apnea (OSA), can impact functional status. In patients with coronary artery disease (CAD) and concomitant OSA, the distinction between sleep-related functional impairment from underlying CAD versus OSA is unclear. This study evaluated the impact of OSA on sleep-related functional impairment in patients with CAD and compared the effect of 1-year continuous positive airway pressure (CPAP) use on change in impairment between those with and without excessive daytime sleepiness (EDS) and OSA. We hypothesized that sleep-related functional impairment is impacted by EDS independent of OSA in patients with CAD.

Methods: One hundred five CAD patients without OSA and 105 with moderate-to-severe OSA from the RICCADSA trial were matched on disease severity and included in the current substudy. Of those with OSA, 80 were allocated to CPAP. Functional Outcomes of Sleep Questionnaire (FOSQ) score < 17.9 corresponded to sleep-related functional impairment.

Results: Following revascularization, CAD patients with and without OSA frequently report sleep-related functional impairment (35% and 27.3%, respectively; p = .29). Moderate-to-severe OSA was not related to baseline FOSQ scores < 17.9 in regression analyses; EDS was (OR 4.82, 95% CI 2.12-11.0; p < .001). CPAP use significantly improved FOSQ scores from baseline to 1-year follow-up in OSA patients with EDS (17.2 ± 2.0 to 18.15 ± 1.7, p = .002) despite suboptimal adherence.

Conclusions: Sleep-related functional impairment may be reflective of persistent EDS, independent of OSA. Diagnosing OSA and initiating treatment are worthwhile in individuals with CAD and EDS, as both are important to guide appropriate therapy in patients with CAD.

Keywords: Continuous positive airway pressure; Coronary artery disease; Functional status; Obstructive sleep apnea.

Conflict of interest statement

Conflict of Interest: All authors certify that they have no affiliations with or involvement in any organization or entity with any financial interest (such as honoraria; educational grants; participation in speakers’ bureaus; membership, employment, consultancies, stock ownership, or other equity interest; and expert testimony or patent-licensing arrangements), or non-financial interest (such as personal or professional relationships, affiliations, knowledge or beliefs) in the subject matter or materials discussed in this manuscript. However, Thunström received consultant fees from ResMed and Pfizer outside the submitted work. Strollo received institutional grants from Philips-Respironics, ResMed, Inspire Medical Systems, National Football League PinMed, and advisory fees from ResMed, Emmi Solutions, Jazz Pharmaceuticals, Itamar Medical, Inspire Medical Systems, Seperation Design Group, all outside the submitted work. Peker received institutional grants from ResMed for the main RICCADSA trial, consultant fees from BresoTec, and lecture fees from ResMed and Philips-Respironics all outside the submitted work.

Figures

Figure 1.

Flow diagram for the study sample. In bold, individuals who were included for baseline and follow-up analyses. Abbreviations: CAD, coronary artery disease; ESS, Epworth sleepiness scale; LVEF, left ventricular ejection fraction; HTN, hypertension; OSA, obstructive sleep apnea.

Figure 2.

The figures depict group mean functional outcomes of sleep questionnaire (FOSQ) total scores and Epworth Sleepiness Scale (ESS) scores at baseline and 1 year for those who used CPAP (nonsleepy OSA and sleepy OSA) and those who did not use CPAP (no OSA). Only the sleepy OSA group demonstrated significant improvements in both FOSQ and ESS scores from baseline to 1-year follow-up.