Sleepiness and sleep in patients with both systolic heart failure and obstructive sleep apnea.
BACKGROUND
Adverse effects of obstructive sleep apnea (OSA), including sleep deprivation, can contribute to the progression of heart failure. The usual indication to diagnose and treat sleep apnea is subjective sleepiness. Previous studies suggest that patients with both heart failure and obstructive sleep apnea often do not complain of sleepiness, albeit their sleep time may be reduced. Therefore, we tested the hypothesis that patients with heart failure have less sleepiness and sleep less compared with subjects without heart failure for a given severity of OSA.


METHODS
Sleepiness assessed with the Epworth Sleepiness Scale and sleep structure measured with polysomnography were compared among 155 consecutive patients with heart failure and from a random community sample (n = 1139) according to categories of the apnea-hypopnea index (<5, no OSA; 5-14, mild OSA; and > or =15, moderate to severe OSA).


RESULTS
Compared with the community sample, for any given severity of OSA, patients with heart failure had lower mean +/- SE Epworth Sleepiness Scale scores (7.1 +/- 0.4 vs 8.3 +/- 0.2 [P = .005]; 6.7 +/- 0.7 vs 9.2 +/- 0.3 [P < .001]; and 7.8 +/- 0.7 vs 9.8 +/- 0.4 [P = .01]), indicating less sleepiness despite sleeping less (total sleep time mean +/- SE [in minutes]: 306 +/- 7 vs 384 +/- 2, 295 +/- 19 vs 384 +/- 5, and 285 +/- 13 vs 359 +/- 7 for no, mild, and moderate to severe OSA, respectively; P < .001 for all comparisons).


CONCLUSIONS
Patients with heart failure have less subjective daytime sleepiness compared with individuals from a community sample, despite significantly reduced sleep time, whether or not they have OSA. In patients with heart failure, the absence of subjective sleepiness is not a reliable means of ruling out OSA.
Arzt
Michael
M
Sleep Research Laboratory of the Toronto Rehabilitation Institute, Center for Sleep Medicine and Circadian Biology, University of Toronto, Toronto, Ontario, Canada.
Young
Terry
T
Finn
Laurel
L
Skatrud
James B
JB
Ryan
Clodagh M
CM
Newton
Gary E
GE
Mak
Susanna
S
Parker
John D
JD
Floras
John S
JS
Bradley
T Douglas
TD
D015992:Body Mass Index; D016022:Case-Control Studies; D006970:Disorders of Excessive Somnolence / Q000453:epidemiology*; D005260:Female; D006333:Heart Failure / Q000453:epidemiology* / Q000503:physiopathology; D006801:Humans; D008297:Male; D008875:Middle Aged; D009864:Ontario / Q000453:epidemiology; D017286:Polysomnography; D011446:Prospective Studies; D012720:Severity of Illness Index; D012890:Sleep / Q000502:physiology; D020181:Sleep Apnea, Obstructive / Q000453:epidemiology*; D011795:Surveys and Questionnaires; D013599:Systole / Q000502:physiology; D013997:Time Factors; D014922:Wisconsin / Q000453:epidemiology