Daytime Sleepiness in Patients With Congestive Heart Failure and Cheyne-Stokes Respiration

To determine whether patients with congestive heart failure who develop Cheyne-Stokes respiration (CSR) during sleep experience excessive daytime sleepiness. This was addressed by comparing sleep quality and daytime sleepiness in three groups: patients with CHF and CSR during sleep (CSR group), patients with CHF without CSR (CHF group), and healthy control subjects (control group). Single-blind, cross-sectional study. Patients referred by cardiologists and control subjects recruited from the general community. Twenty-three men: 7 in the CSR group, 7 in the CHF group, and 9 in the control group. Each subject had an overnight sleep study and an assessment of sleepiness the following day. The three groups were a similar age: CSR, 68 ± 5 years; CHF, 62 ± 4 years; and control, 65 ± 4 years; and left ventricular ejection fraction was the same in patients with CSR (20 ± 1.5%) and CHF (23 ± 5%). Sleep latency was significantly shorter in patients with CSR (4 ± 1.1 min) than patients with CHF (11.3 ± 4.8 min) and healthy controls (12.4 ± 1.9 min) and was within the diagnostic range of severe sleepiness. Patients with CSR had significantly more stage 1 and 2 non-rapid eye movement (NREM) sleep (CSR, 83 ± 7; CHF, 64 ± 9; control, 63 ± 9% total sleep time), less REM sleep (CSR, 10 ± 3; CHF, 22 ± 8; control, 22 ± 7% total sleep time), and a higher frequency of arousals from sleep (CSR, 30 ± 16; CHF, 18 ± 15; control, 10 ± 2/h of sleep); 66% of arousals were associated with CSR. Regression analysis revealed that sleep latency was inversely related to the amount of stage 1 and 2 NREM sleep (r= “0.67), arousal frequency (r= −0.46), and the apnea-hypopnea index (r = −0.63) and was positively correlated with the amount of slow-wave sleep (r=0.45) and REM sleep (r=0.56) and the mean oxygen saturation during sleep (r=0.50). Patients with CHF who develop CSR experience excessive daytime sleepiness due to sleep disruption. This should be considered the clinical evaluation of these patients’ daytime complaints.