Abstract:

Objective To explore the effects of obstructive sleep apnoea syndrome (OSAS) on non-alcoholic fatty liver disease (NAFLD). Methods This study is an observational study, which recruited 159 patients who have been diagnosed with OSAS (the OSAS group) among patients visiting the Department of Gerontology at Ruijin Hospital affiliated to Shanghai Jiao Tong University School of Medicine due to snore between January 2009 and December 2015 and 159 non-OSAS patients (the control group). Mann-Whitney U non-parametric test was used to analyze whether the OSAS group matched with the control group and the incidence of NAFLD in two groups was compared. The OSAS group was divided into mild, moderate, and severe subgroups according to the apnea hyponea index (AHI) and lowest oxyhemoglobin saturation (L-SaO2). Chi-square R×C contingency table was employed to statistically analyze the prevalence of NAFLD in OSAS subgroups. Results The OSAS group had a higher AHI (P=0.000), a lower level of L-SaO2 (P=0.000), a longer duration of hemoglobin desaturation (TSaO2<90%)(P=0.000), and a higher incidence of NAFLD (P=0.016) as compared with the control group. The difference in the NAFLD incidence in OSAS subgroups stratified by AHI and L-SaO2 was statistically significant AHI (χ2=6.455, P=0.040; χ2=6.097, P=0.047). Conclusion OSAS can increase the incidence of NAFLD and the incidence of NAFLD increases with the degree of hypoxia in patients with OSAS.

Key words: obstructive sleep apnoea syndrome；non-alcoholic fatty liver disease, apnea hyponea index, lowest oxyhemoglobin saturation