Study On The Risk Factors For Elevated Liver Enzymes And Nonalcoholic Fatty Liver Disease In Obstructive Sleep Apnea Hypopnea Syndrome

Background and ObjectiveObstructive sleep apnea hypopnea syndrome is a group of diseases characterized by repeated episodes of apnea and hypopnea,recurrent hypoxemia and sleep structural disorders during sleep which due to upper respiratory obstruction.Its incidence has been increasing worldwide and it has been confirmed that obstructive sleep apnea hypopnea syndrome is associated with hypertension,diabetes,cardiovascular and cerebrovascular diseases,metabolic syndrome and other systemic diseases.Recent studies have found that OSAHS is associated with the development and progression of nonalcoholic fatty liver disease（NAFLD）.It has been reported in the literature that chronic intermittent hypoxia（CIH）may be an important cause of liver injury in OSAHS.Our study investigated the serum liver enzymes and the incidence of nonalcoholic fatty liver disease in patients with OSAHS,and further clarified the risk factors of elevated liver enzymes and non-alcoholic fatty liver disease in OSAHS to provide a basis for early detection and intervention of liver injury associated with OSAHS patients.Subjects and MethodA total of 196 patients who admitted to the First Affiliated Hospital of Zhengzhou University due to sleep disorder from September 2017 to January 2019were included.All patients underwent polysomnography（PSG）in the sleep center of the elderly respiratory sleep department.A total of 142 patients were in the OSAHS group,and 54 patients were in the non-OSAHS group.Patients in the OSAHS group were further divided into mild-to-moderate OSAHS group and severe OSAHS group according to the sleep apnea hypopnea index（AHI）.Questionnaire,human indicators,serum transaminase test,blood lipids test and abdominal ultrasound examination were applied to all patients.Statistical analysis was performed using SPSS21.0 statistical software.Differences in age,BMI,ESS score,PSG related parameters,liver enzyme,FLD and fatty liver incidence were compared between the groups.According to whether NAFLD was combined,the observed components were divided in NAFLD group and non-NAFLD group,and the differences of age,BMI,PSG related parameters and other indicators were compared between the two groups.Correlation analysis between BMI,PSG parameters and liver enzymes were performed.Binary logistic regression with increasing liver enzyme and nonalcoholic fatty liver as the outcome variable was conducted respectively.α=0.05 as the test level.Result1.There were no significant differences in age,gender,smoking history and drinking history among the control group,the mild-to-moderate OSAHS group and the severe OSAHS group（P>0.05）;The BMI and ESS score of the severe OSAHS group were higher than those of the mild-moderate OSAHS group and the control group,the difference was statistically significant（P<0.05）;The prevalence of diabetes mellitus and hypertension in severe OSAHS group was higher than that in the control group（P<0.05）,the difference was statistically significant（P<0.05）.2.The results of PSG monitoring showed that the AHI,ODI,CT90 and total apnea time of the severe OSAHS group were higher than those of the mild-moderate OSAHS group and the control group,while LSaO₂ was lower than that of the mild-moderate OSAHS group and the control group,the difference was statistically significant（P<0.01）.3.The ALT,AST,GGT,TC（cholesterol）,FLD,abnormal ALT ratio,abnormal AST ratio,abnormal GGT ratio,proportion of elevated liver enzymes and fatty liver morbidity in the observation group were higher than those in the control group,with statistical significance（P<0.05）.4.There were significant differences in ALT,AST,GGT,TC,TG,abnormal ALT ratio,abnormal AST ratio,abnormal GGT ratio,proportion of elevated liver enzymes,fatty liver morbidity and FLD among the control group,the mild-moderate OSAHS group and the severe OSAHS group（P<0.05）.The ALT,GGT,FLD,abnormal GGT ratio and proportion of elevated liver enzymes in the severe OSAHS group were higher than those in the mild-moderate OSAHS group and the control group,the difference was statistically significant（P<0.05）;The AST,abnormal AST ratio,abnormal ALT ratio and fatty liver morbidity in the severe OSAHS group was higher than that in the control group（P<0.05）,while there were no significant difference between the severe OSAHS group and the mild-moderate OSAHS group（P>0.05）;The proportion of abnormal ALT ratio and FLD in the mild-moderate OSAHS group were higher than those in the control group（P<0.05）,whle there were no significant differences in ALT,AST,GGT,abnormal AST ratio,abnormal GGT ratio,proportion of elevated liver enzymes and fatty liver morbidity between the two groups（P>0.05）.5.There were no significant difference in age,sex,history of diabetes mellitus,history of hypertension and TC between the NAFLD group and the non-NAFLD group（P>0.05）;The BMI,AHI,ODI,CT90,total apnea time,FLD,TG and ESS scores in the NAFLD group were higher than those in the control group（P<0.05）;The LSaO₂ in the NAFLD group was lower than that in the non-NAFLD group,and the difference was statistically significant（P<0.05）.6.ALT level and BMI（r=0.375 P=0.000）,ODI（r=0.555 P=0.000）,AHI（r=0.428P=0.000）,CT90（r=0.449 P=0.000）,total apnea time（r=0.359 P=0.000）,ESS score（r=0.320 P=0.000）was positively correlated,while negatively correlated with LSaO₂（r=-0.377 P=0.000）;AST level and BMI（r=0.181 P=0.011）,ODI（r=0.386P=0.000）,AHI（r=0.318 P=0.000）,CT90（r=0.289 P=0.001）,total apnea time（r=0.265 P=0.000）,ESS score（r=0.225 P=0.002）was positively correlated,while negatively correlated with LSaO₂（r=-0.219 P=0.002）;GGT level and BMI（r=0.440P=0.000）,ODI（r=0.645 P=0.000）,AHI（r=0.498 P=0.000）,CT90（r=0.526 P=0.000）,total apnea time（r=0.419 P=0.000）was positively correlated,while negatively correlated with LSaO₂（r=-0.459 P=0.000）.7.Bivariate logistic regression was performed with elevated liver enzymes as outcome variables,BMI,AHI,CT90,ODI,LSaO₂,total apnea time and ESS score as independent variables.The results showed that ODI and LSaO₂ were risk factors for elevated liver enzymes.The regression coefficients were 0.089（P=0.000）,0.073（P=0.020）,and OR values were 1.093 and 1.075,respectively.8.Logistic regression was performed Nonalcoholic fatty liver disease was the outcome variable,with BMI,AHI,CT90,ODI,LSaO_2,total apnea time,TG,ESS score as independent variables.The results showed that ODI,CT90 and BMI were risk factors for NAFLD.The regression coefficients were 0.028（P=0.019）,0.030（P=0.016）,0.190（P=0.008）,and the OR values were 1.029,1.031 and 1.209,respectively.Conclusion1.The incidence of liver enzymes elevation and non-alcoholic fatty liver disease is higher in OSAHS patients.2.Chronic intermittent hypoxia may be a risk factor for liver enzymes elevation in OSAHS patients.3.Chronic intermittent hypoxia and BMI may be risk factors for OSAHS patients with NAFLD.