Introduction: In patients with heart failure (HF) and reduced ejection fraction (HFrEF), obstructive sleep apnea (OSA) and central (CSA)are associated with increased morbidity and mortality. Prior studies suggest that those with CSA have more advanced HF than those without, such that CSA may reflect worse HF. There is no such evidence for OSA.

Objective: To test the hypothesis that among patients in the ADVENT-HF trial, those with CSA have higher morbidity and mortality rates than those with OSA.

Methods: Among patients in the ADVENT-HF trial, we compared the incidence of the primary endpoint (PE) [all-cause mortality, cardiovascular (CV) hospitalizations, new-onset atrial fibrillation , defibrillator shocks], all-cause mortality and CV mortality between those with OSA and CSA by Cox proportional hazard models.

Results: We included 533 patients with OSA and 198 with CSA. The CSA group had a lower left ventricular ejection fraction (LVEF, mean 32% SD ±8 vs 34% SD±8, p=0.003). In unadjusted analyses the CSA group had a higher PE rate [hazard ratio (HR) 1.27, p=0.05], all-cause mortality (HR1.58, p=0.01) and CV mortality (HR 1.91, p<0.001). In a model adjusted for age, sex, BMI, atrial fibrillation, LVEF and ischemic cardiomyopathy, we found no difference between groups for the PE (p=0.28) or all-cause mortality (p=0.10), but CV mortality remained significantly higher in the CSA group (HR 1.51, p=0.04). LVEF was the only factor consistently associated with these outcomes in all analyses.

Conclusion: Higher CV mortality in patients with CSA than those with OSA may be due to worse heart function as well as CSA per se.