Study on the independent effect of thyroid hormone based on uric acid level on NAFLD

This study aims to explain the correlation among non-alcoholic fatty liver disease (NAFLD), hyperuricemia, and thyroid function and to find independent risk factors for each other.

Data were obtained from subjects who underwent health examination in the Health Promotion Centre of Sir Run Run Shaw Hospital of Zhejiang University from January 2017 to February 2019. The diagnosis of NAFLD was according to the clinical diagnosis of the guidelines. Serum uric acid (SUA) > 360 μmol/L (female) and SUA > 420 μmol/L (male) were enrolled in the hyperuricemia group. R software was used for statistical analysis.

55,449 subjects were included in the analysis. 34.27% of patients were classified as NAFLD group (N=19004), and 65.73% of patients were classified as non-NAFLD group (N=36445). The levels of gender ratio, age, BMI, waist circumference, systolic blood pressure (SBP), diastolic blood pressure (DBP), fasting blood glucose (FBG), HbA1c, triglyceride (TG), high-density lipoprotein (HDLC), alanine aminotransferase (ALT), aspartate aminotransferase (AST), urea nitrogen (BUN), creatinine (CR), FT3, FT4, and TSH were significantly different between the non-NAFLD group and NAFLD group. Age, BMI, waist circumference, DBP, fFBG, HbA1c, total cholesterol (TC), low-density lipoprotein (LDLC), AST, and UA were all independent risk factors for NAFLD. In the normal uric acid group, variables other than SBP and TSH were independent factors of NAFLD. In the hyperuricemia group, all variables except SBP, FT4, and TSH were independent factors of NAFLD.

The level of uric acid is related to the occurrence of NAFLD. Hyperuricemia is one of the independent risk factors of NAFLD. TSH level is not related to the occurrence of NAFLD, while FT3 and FT4 may be related to NAFLD.