Analysis of influencing factors of excessive daytime sleepiness in adults with different degrees of sleep-disordered breathing

Abstract

Objective:To explore the main influencing factors of excessive daytime sleepiness（EDS） in adults with different degrees of sleep-disordered breathing（SDB）, which will provide the scientific evidences for the individualized diagnosis and treatment. Method:Retrospective analysis was performed on the clinical data of 361 young and middle-aged snoring patients monitored by polysomnography. According to the presence or absence of obstructive sleep apnea（OSA） and apnea hypopnea index（AHI） levels, they were divided into primary snoring（AHI<5）, mild OSA（AHI 5-<15）, moderate OSA（AHI 15-<30） and severe OSA（AHI≥30）. From sleep efficiency（ES）, different sleep stages（REM, NREM1, NREM2, NREM3） ratio of total sleep, oxygen reduction index（ODI）, blood oxygen saturation<90% of total sleep time（TS90%）, the average saturation of blood oxygen（MSaO₂） and the lowest blood oxygen saturation（LSaO₂） of all-night sleep, and AHI in different sleep stages（REM-AHI, NREM-AHI）, MSaO₂ in different sleep stages（REM-MSaO₂, NREM-MSaO₂） and LSaO₂ in different sleep stages（REM-LSaO₂, NREM-LSaO₂）, the main influencing factors of EDS were discussed. Result:Among the 361 patients, 23 patients suffered from the primary snoring, 47 patients with mild OSA, 56 patients with moderate OSA, and 235 patients with severe OSA. REM-AHI, ODI and TS90% in EDS group were 10.9, 9.6 and 0.2 respectively in patients with primary snoring, which were significantly higher than those without EDS（P<0.01）. The main influencing factors of EDS were REM-AHI, ODI, and TS90%. However, among patients with mild OSA, REM-AHI was the main influencing factor of EDS, REM-AHI of the EDS group was 29.6, which was significantly higher than that of the non-EDS（P<0.05）. In patients with moderate OSA, LSaO₂ of the EDS group was 76.2, significantly lower than the group without EDS（P<0.05）, the main influencing factor of EDS is LSaO₂. In patients with severe OSA, BMI, ODI and TS90% in EDS group were significantly higher than those without EDS（P<0.05 or P<0.01）, while NREM-MSaO₂, MSaO₂ and LSaO₂ were significantly lower than those without EDS（P<0.05 or P<0.01）. The main influencing factors of EDS were BMI, NREM-MSaO₂, MSaO₂, LSaO₂, ODI and TS90%. Conclusion:Frequent apnea during REM stage may be one of the important factors causing EDS in patients with primary snoring and mild OSA. For patients with moderate and severe OSA, intermittent hypoxia at night may be the main factor leading to EDS, and obesity may promote the development of the disease and the occurrence of sleepiness.