Relationship between serum uric acid levels and hepatic steatosis in non-obese postmenopausal women

Objective Serum uric acid levels have been reported to be associated with non-alcoholic fatty liver disease (NAFLD). However, very few studies specifically examining the relationship between serum uric acid (SUA) levels and NAFLD in postmenopausal women have been reported in China, especially in postmenopausal women with normal body mass index (BMI) in whom NAFLD is not uncommon. Methods A cross-sectional study was employed of 528 Chinese normal-BMI postmenopausal women (aged 41-79 years) who participated in annual health check-ups. NAFLD is defined as a hepatic steatosis observed on liver ultrasonography in the absence of a second cause. Of all the participants, 121 women were diagnosed with hepatic steatosis (NAFLD group) and the others were without (non-NAFLD group). SUA quartiles were defined as follows: Q1, <3.8 mg/dl; Q2, 3.8-4.4 mg/dl; Q3, 4.5-5.0 mg/dl; Q4, 5.1-6.0 mg/dl. Stepwise multivariable regression analysis was used to assess the relationships between SUA level and other variables. The association between SUA quartiles and hepatic steatosis was assessed using binary logistic regression. Results Compared to the non-NAFLD group, the mean level of SUA was significantly higher in the NAFLD group (p < 0.01). The adjusted odds ratio (95% confidence interval) for the presence of hepatic steatosis in the highest SUA quartile vs. the lowest quartile was 2.774 (1.396-5.513) for all women (p < 0.01) after adjusting for the factors which were independently associated with uric acid level including waist circumference, high blood pressure, blood urea nitrogen, creatinine, gamma-glutamyltransferase, and triglycerides. Most estimates changed little after further adjustment for age, metabolic syndrome, drinking status, and smoking status. The presence of hepatic steatosis significantly increased in the third and fourth quartiles of SUA. The prevalence of hepatic steatosis increased gradually with an increasing SUA quartile (p for trend < 0.01). Conclusion Higher SUA levels even within the normal range are positively and independently associated with the presence of hepatic steatosis in Chinese postmenopausal women with normal BMI.