Study On The Relationship Between Excessive Daytime Sleepiness And The Parameters Of Obstructive Sleep Apnea Syndrome

Objectives:To find the relationship between the indexes about obstructive sleep apnea-hypopnea syndrome(OSAHS ) and the excessive daytime sleepiness(EDS ) in OASAH patients.To clarify the factor of EDS in OSAHS patients,and investigate the pathogenesis for EDS induced by OSAHS.Methods:525 consecutive OSAHS patients referred to our hospital between January 2006 and December 2008 were prospectively enrolled.There were 279 patients were selected randomly for sleep structure statistical anlysis.Nocturnal polysomnography was performed in each patient for at least 7 h,and the following parameters were collected,AHI,SpO₂ and sleep structures.EDS was assessed using the Epworth sleepiness scale(ESS).SPSS 11.5 software package was used for statistical analysis. Results:Patients with severe EDS had higher BMI(30.3±3.8) than those with mild EDS (28.3±3.9) and those without EDS(27.8±4.3),P<0.0167.A correlation was found between ESS score and BMI after modifying confounding factors,such as sex,AHI, mix pulse oxyhemoglobin saturation(SpO2),mean SpO2,T90,smoking,drinking, r=0.136,p=0.003.Ordinal logistic regression showed that BMI influenced EDS independently,OR=1.080,p=0.008.Patients with severe EDS had higher AHI[65.9(34.1)],AI[56.5(42.8)]than those with mild EDS AHI[47.5(41.5)],AI[32.3(41.7)];and patients without EDS had lower AHI[36.0(40.0)],AI[21.8(37.3)]than those with mild EDS,p<0.0167.A correlation was found between ESS score and AHI after modifying confounding factors,such as sex,BMI,mix SpO2,mean SpO2 and T90,smoking,drinking, r=0.146,p=0.001.Ordinal logistic regression showed that AHI influenced EDS independently,OR=1.022,p=0.001.Patients with severe EDS had lower mix SpO2[66.7(20.0)],mean SpO2[90.3(8.0)] than those with mild EDS[mix SpO2[74.0(17.2)],mean SpO2[93.0(5.0)]]and those without EDS[mix SpO2[78.0(15.1)],mean SpO2[94.0(3.8)]],p<0.0167;patients with severe EDS had higher T90[32.2(43.0)]than those with mild EDS [13.9(30.2)]and those without EDS[9.0(21.2)].A correlation was found between ESS score and mix SpO2,mean SpO2,T 90 after modifying confounding factors,such as sex,BMI,AHI,smoking,drinking,r=-0.137,-0.090,r=0.103,p<0.05.Ordinal logistic regression showed that mean SpO2 influenced EDS independently,OR=0.942, p=0.039.Patients with severe EDS had higher sleep efficiency[94.8(8.1)],Sl%[46.8±23.8]than those without EDS[sleep efficiency 88.8(11.7),S1%[30.0±19.1]];and Patients with severe EDS had lower S3+4%[0.8(7.7)]than those without EDS[8.9(19.9)],p<0.0167.A correlation was found between ESS score and sleep efficiency,S1%,S3+4%after modifying confounding factors,such as sex,BMI,AHI, mix SpO2,mean SpO2 and T90,smoking,drinking,r =0.191,0.143,-0.129, p<0.05.Ordinal logistic regression showed that sleep efficiency can reflect the severity of EDS independently,OR=1.045,p=0.005.There were more people smoked in the patients with EDS.Ordinal logistic regression showed that smoking influenced EDS independently,OR=0.615,p=0.012. Conclusions:OSAHS is significantly correlated with EDS.AHI,mean SpO2 and sleep structure can influence EDS in OSAHS patients.If AHI increase,EDS will be more serious.And it is the same when the mean SpO2 decrease and the Sl%increase. Sleep efficiency can reflect the severity of EDS independently.BMI,drinking, smoking may induce EDS or aggravate EDS.