Analysis Of The Correlation Between Obstructive Sleep Apnea And Nonalcoholic Fatty Liver Disease

Objective: To explore the correlation between obstructive sleep apnea and nonalcoholic fatty liver disease.At the same time,the non-invasive liver fibrosis score FIB-4 and FNS were used to evaluate the risk of liver fibrosis in patients with different degrees of OSA complicated with NAFLD,and to identify the clinical indicators and polysomnography monitoring parameters related to the non-invasive liver fibrosis score.Methods: Using the electronic case system of the first hospital of Lanzhou University,we selected the patients who were hospitalized in our hospital from January2017 to December 2021.The patients who completed the B-ultrasound examination of abdomen,met the diagnosis of nonalcoholic fatty liver disease and underwent polysomnography monitoring as the research objects.A total of 212 cases were included.According to the AHI,they were divided into four groups:（I）non OSA group,（II）mild group,（III）moderate group and（IV）severe group,with 30,45,56 and 81 cases in the four groups respectively.The demographic data,serological test results and polysomnography monitoring parameters of these patients were collected,and NAFLD fibrosis score（NFS）and fibrosis-4 index（FIB-4）were calculated.Statistical analysis was conducted to compare the differences and correlations among the four groups.Binary logistic regression was used to analyze the risk factors of elevated liver enzymes in patients with OSA and NAFLD.Liver fibrosis score was used to predict the risk of liver fibrosis in patients with OSA and NAFLD.Multivariate linear regression was used to analyze the risk factors of FIB-4 and NFS.Results:1.There was significant difference in BMI among the four groups（P < 0.001）.There was no significant difference among the four groups in terms of gender,age,prevalence of diabetes and hypertension（all P > 0.05）.2.The biochemical indexes,NFS and FIB-4 in each group were compared.It was found that with the increase of OSA severity,AST,NFS and FIB-4 increased.There were significant differences in AST,NFS and FIB-4 among the four groups（all P <0.05）.ALT,ALB,γ-GGT,ALP,TG,TC,LDL-C and Glu had no statistical significance（all P > 0.05）.There were significant differences in TBIL and HDL-C among the four groups（all P < 0.05）.3.With the increase of the severity of OSA,LSa O2 and MSa O2 decreased in patients with OSA and NAFLD,and the times of oxygen reduction within 90%,the total times of oxygen reduction of 4% and ODI increased.It was found that there were significant differences in LSa O2,MSa O2,times of oxygen reduction within 90%,total times of oxygen reduction 4% and ODI among the four groups（all P < 0.001）.4.Spearman correlation analysis of AST and ALT with other clinical indexes showed that AST was related to BMI,AHI,times of oxygen reduction within 90%,total times of oxygen reduction of 4%,ODI,ALB,γ-GGT and ALP were positively correlated（r = 0.195,0.302,0.280,0.286,0.317,0.137,0.323,0.219,all P < 0.05）,and negatively correlated with age,LSa O2 and MSa O2（r =-0.135,-0.234,-0.166,all P <0.05）.ALT and gender,ALB,γ-GGT was positively correlated（r = 0.187,0.226,0.524,all P < 0.05）,and negatively correlated with age（r =-0.397,P < 0.001）.5.Univariate analysis using binary logistic regression found that BMI,AHI,LSa O2,MSa O2,the number of oxygen reduction within 90%,the total number of oxygen reduction of 4%,ODI,ALB and γ-GGT was associated with the increase of liver enzymes in patients with OSA complicated with NAFLD（P < 0.05）.Multivariate analysis showed that BMI（OR = 1.143,95% CI: 1.015-1.286,P = 0.028）,LSa O2（OR= 0.942,95% CI: 0.888-0.999,P = 0.047）,ODI（OR = 1.082,95% CI: 1.010-1.159,P= 0.024）,γ-GGT（OR= 1.024,95% CI: 1.011-1.037,P < 0.001）was an independent risk factor for elevated liver enzymes in patients with OSA complicated with NAFLD.6.Multiple linear regression analysis with FIB-4 as dependent variable showed that MSa O2,platelet,AST,ALT,γ-GGT and ALP were the influencing factors of FIB-4（P < 0.05）.Multiple linear regression analysis with NFS as dependent variable showed that age,BMI,diabetes,hypertension,platelets,AST,ALT,Glu and ALB were the influencing factors of NFS（P < 0.05）.Conclusions:1.LSa O2 and ODI are independent risk factors for liver injury in patients with OSA complicated with NAFLD.2.Chronic intermittent hypoxia of OSA may lead to the occurrence and progression of NAFLD.Patients with severe OSA and NAFLD are more likely to be recorded with high NFS and FIB-4 scores.3.MSa O2 was found to be a risk factor for FIB-4,which may indicate that there is a link between CIH caused by OSA and the progression of NAFLD to liver fibrosis.