Clinical Research
Heart Failure
Influence of Obstructive Sleep Apnea on Mortality in Patients With Heart Failure

https://doi.org/10.1016/j.jacc.2006.12.046Get rights and content
Under an Elsevier user license
open archive

Objectives

This study sought to determine, in patients with heart failure (HF), whether untreated moderate to severe obstructive sleep apnea (OSA) is associated with a higher mortality rate than in patients with mild to no sleep apnea (M-NSA).

Background

Obstructive sleep apnea is common in patients with HF and exposes the heart and circulation to adverse mechanical and autonomic effects. However, its effect on mortality rates of patients with HF has not been reported.

Methods

In a prospective study involving 164 HF patients with left ventricular ejection fractions (LVEFs) ≤45%, we performed polysomnography and compared death rates between those with M-NSA (apnea-hypopnea index [AHI] <15/h of sleep) and those with untreated OSA (AHI ≥15/h of sleep).

Results

During a mean (± SD) of 2.9 ± 2.2 and a maximum of 7.3 years of follow-up, the death rate was significantly greater in the 37 untreated OSA patients than in the 113 M-NSA patients after controlling for confounding factors (8.7 vs. 4.2 deaths per 100 patient-years, p = 0.029). Although there were no deaths among the 14 patients whose OSA was treated by continuous positive airway pressure (CPAP), the mortality rate was not significantly different from the untreated OSA patients (p = 0.070).

Conclusions

In patients with HF, untreated OSA is associated with an increased risk of death independently of confounding factors.

Abbreviations and Acronyms

AHI
apnea-hypopnea index
BMI
body mass index
CPAP
continuous positive airway pressure
HF
heart failure
HR
hazard ratio
LVEF
left ventricular ejection fraction
M-NSA
mild to no sleep apnea
NYHA
New York Heart Association
OSA
obstructive sleep apnea
Sao2
arterial oxygen saturation
SNA
sympathetic nervous system activity

Cited by (0)

Supported by operating grant MOP 11607 from the Canadian Institutes of Health Research.

1

Dr. Wang was supported by research fellowships from the Department of Medicine of the University of Toronto and Merck-Frosst

2

Dr. Parker by a Career Investigator Award from the Heart and Stroke Foundation of Ontario

3

Dr. Floras by a Canada Research Chair in Integrative Cardiovascular Biology and a Career Investigator Award from the Heart and Stroke Foundation of Ontario

4

Dr. Mak by a New Investigator Award from the Heart and Stroke Foundation of Ontario

5

Dr. Chiu by an unrestricted research fellowship from Respironics Inc. and The ResMed Foundation

6

Dr. Ruttanaumpawan by a research fellowship from Siriraj Hospital, Bangkok, Thailand

7

Dr. Bradley by a Career Investigator Award from the Canadian Institutes of Health Research.