Daytime Sleepiness and Nocturnal Hypoxemia in Obstructive Sleep Apnea-hypopnea Syndrome Patients

Objective To evaluate the relationship between excessive daytime sleepiness and nocturnal hypoxeamia. Methods Polysomnography was carried out and the Epworth Sleepiness Scale(ESS) was evaluated in ninety OSAHS patients,who were,then,divided into two groups according to ESS,and multiple stepwise regression was used. Results Patients with sleepiness had higher ESS Scale(ESS Scale 16.37±4.19 and 2.7±2.26,respectively,P 0.001),AHI [(44.81±22.04)/h vs (20.24±13.56)/h,P 0.05] and nocturnal oxygen saturation index[(49.87±24.03)/h vs(24.88±14.22)/h,P 0.05],and had lower nadir nocturnal oxygen saturation[(68.21±10.93)% vs (77±6.32)%,P 0.05] than the controls. Multiple stepwise regression showed that ESS was correlated with nocturnal oxygen saturation index(R2=0.303,P 0.05). Conclusion ESS is closely correlated with nocturnal oxygen saturation index in OSAHS patients. Nocturnal hypoxaemia can be a major determinant of excessive daytime sleepiness in patients with obstructive sleep apnea-hypopnea syndrome.patients with obstructive sleep apnea-hypopnea syndrome.