Correlation of Epworth Sleepiness Scale with multiple sleep latency test and its diagnostic accuracy in assessing excessive daytime sleepiness in patients with obstructive sleep apnea hypopnea syndrome

Background Excessive daytime sleepiness （EDS） is often associated with obstructive sleep apnea hypopnea syndrome （OSAHS） and contributes to a number of comorbidities in these patients. Therefore, early detection of EDS is critical in disease management. We examined the association between Epworth Sleepiness Scale （ESS） and multiple sleep latency test （MSLT） and diagnostic accuracy of ESS in assessing EDS in OSAHS patients. Methods The ESS, MSLT and overnight polysomnography were administered to 107 Chinese patients to assess EDS and its correlations with polysomnographic parameters. The diagnostic accuracy of ESS in classifying EDS （mean sleep latency （MSL） 〈10 minutes） was evaluated by calculating the area under ROC curve. Results As the severity of OSAHS increased, MSL decreased with increase in ESS score. Conversely, patients with worsening EDS （shorter MSL） were characterized by advanced nocturnal hypoxaemia and sleep disruption compared to those with normal MSL, suggesting EDS is associated with more severe OSAHS. There was a negative correlation between ESS score and MSL and both moderately correlated with some polysomnographic nocturnal hypoxaemic parameters. The area under ROC curve of ESS for identifying EDS was 0.80 （95% CI： 0.71 to 0.88） and ESS score 〉12 provided the best predictive value with a sensitivity of 80% and specificity of 69%. Conclusion The ESS score moderately correlates with MSL and our ROC study supports ESS as a screening strategy for assessing EDS in OSAHS.

Analysis of sleep characteristics and clinical outcomes of 139 adult patients with infective endocarditis after surgery

BACKGROUND Little is known about the postoperative sleep quality of infective endocarditis patients during hospitalization and after discharge.AIM To investigate the sleep characteristics of infective endocarditis patients and to identify potential risk factors for disturbed sleep quality after surgery.METHODS The Pittsburgh Sleep Quality Index(PSQI)and the Epworth Sleepiness Scale were used to assess patient sleep quality.Logistic regression was used to explore the potential risk factors.RESULTS The study population(n=139)had an average age of 43.40±14.56 years,and 67.6%were men(n=94).Disturbed sleep quality was observed in 86 patients(61.9%)during hospitalization and remained in 46 patients(33.1%)at 6 mo after surgery.However,both PSQI and Epworth Sleepiness Scale scores showed significant improvements at 6 mo(P<0.001 and P=0.001,respectively).Multivariable logistic regression analysis showed that the potential risk factors were age(odds ratio=1.125,95%confidence interval:1.068-1.186)and PSQI assessed during hospitalization(odds ratio=1.759,95%confidence interval:1.436-2.155).The same analysis in patients with PSQI≥8 during hospitalization suggested that not using sleep medication(odds ratio=15.893,95%confidence interval:2.385-105.889)may be another risk factor.CONCLUSION The incidence of disturbed sleep after infective endocarditis surgery is high.However,the situation improves significantly over time.Age and early postoperative high PSQI score are risk factors for disturbed sleep quality at 6 mo after surgery.

Subjective sleepiness in heart failure patients with sleep-related breathing disorder

Background Previous studies show that sleep-related breathing disorder （SRBD） is common in patients with heart failure （HF） and is associated with increased mortality. This study aimed to determine whether there was significant difference of subjective daytime sleepiness between HF patients with and without SRBD. Methods We enrolled, prospectively, 195 consecutive HF patients with left ventricular ejection fractions （LVEF） ≤45% and all subjects underwent polysomnography to measure the sleep structure between 2005 and 2008. Patients were then assigned to those with SRBD including obstructive and central sleep apnea （apnea-hypopnea index （AHI） ≥5/hour of sleep） and those without SRBD （AHI 〈5/hour） according to the sleep study. The subjective sleepiness was assessed with Epworth sleepiness scale （ESS）. Results Among 195 HF patients, the prevalence of obstructive sleep apnea （OSA） was 53% and of central sleep apnea （CSA） was 27%. There was no significant difference of ESS scores between patients without SRBD （NSA） and with SRBD （NSA vs OSA： 6.7±0.6 vs 7.6±0.4, P=0.105 and NSA vs CSA： 6.7±0.6 vs 7.4±K）.5, P=0.235, respectively）, indicating that SRBD patients had no more subjective daytime sleepiness. Compared with NSA, patients with SRBD had increased arousal index （Arl） （NSA vs OSA： 14.1±1.4 vs 26.3 ±1.5, P〈0.001 and NSAvs CSA： 14.1±1.4 vs 31.3±3.5, P 〈0.001, respectively）, more awake number after sleep onset （NSA vs OSA： 19.2±1.5 vs 26.2±1.4, P=0.01 and NSA vs CSA： 19.2±1.5 vs 36.9±4.4, P 〈0.001, respectively）, and reduced proportion of slow-wave sleep （SWS） （NSA vs OSA： 13.8±1.7 vs 9.3±0.7, P=0.024 and NSA vs CSA： 13.8±1.7 vs 8.9±0.9, P=0.024, respectively）. Conclusions OSA and CSA remain common in patients with HF on optimal contemporary therapy. Patients with both HF and SRBD have no significant subjective daytime sleepiness compared with patients without SRBD, despite of significantly increased awake number, arousal and decreased proportion of deep sleep stages. It is not a credible way and means to exclude SRBD in patients with HF according to the absence of subjective daytime sleepiness.