Prognostic impact of sleep-disordered breathing and its treatment with nocturnal ventilation for chronic heart failure

Abstract

Aims: To determine whether severity patterns or nocturnal ventilation to treat sleep-disordered breathing (SDB) during chronic heart failure (CHF) is associated with adverse outcomes. Although SDB is frequent during CHF, the relationships between SDB and CHF outcomes are unknown.

Methods and results: A total of 384 CHF patients (82% men, mean age 59 ± 13 years) with a left ventricular ejection fraction (LVEF) of ≤45% (mean LVEF 29 ± 9%) were assessed by polygraphy in our clinic between 2001 and 2009. Nocturnal ventilation was started according to the severity of SDB. Combined endpoints were death, heart transplant, and implant of a ventricular assist device. The prevalence of obstructive sleep apnoea (OSA), central sleep apnoea (CSA), and Cheyne-Stokes respiration (CSR) was 62, 26, and 29%, respectively. A primary endpoint occurred in 31%. Mean follow-up for survivors was 47 ± 25 months. Those with moderate [apnoea-hypopnoea index (AHI) ≤5-20/h] and severe SDB (AHI ≥20/h), and OSA and CSA, had poor prognoses compared with patients without SDB (P = 0.036, P = 0.003, respectively). A total of 31% of SDB patients were treated with nocturnal ventilation. Treated SDB had a better outcome than untreated severe SDB after adjustment for confounding factors [P = 0.031; hazard ratio (HR) 0.56; 95% confidence interval (CI) 0.33-0.95]. Subgroup analysis that included only OSA showed a similar result after adjustment (P = 0.017; HR 0.40; 95% CI 0.19-0.95).

Conclusions: In CHF, SDB is associated with a poor prognosis whatever the SDB pattern, and nocturnal ventilation is associated with a better outcome.