Research On The Correlation Between Adult Subclinical Hypothyroidism And Nonalcoholic Fatty Liver Disease

Objective(s):To explore the association between subclinical hypothyroidism(SCH)and non-alcoholic fatty liver disease(NAFLD),as well as the risk factors affecting the prevalence of NAFLD in different genders,hoping to provide a new direction for the prevention and treatment of NAFLD.Methods:The study subjects were selected for people who underwent health examinations at the health checkup center of the Second Affiliated Hospital of Kunming Medical University from January 2022 to April 2022.Blood indicators such as demographic data,physical examination,liver function,blood lipids,fasting blood glucose,and thyroid function were collected for those who met the inclusion criteria after exclusion.Abdominal ultrasound was used to diagnose whether the subject had fatty liver,and thyroid function test was used to diagnose subclinical hypothyroidism.Finally,420 eligible subjects were included,and according to the ultrasound results and the exclusion criteria of NAFLD,the study population was divided into 220 cases in the non-NAFLD group and 200 cases in the NAFLD group,and the general data(age,sex,height,weight,BMI)and laboratory test results(liver enzymes,blood lipids,blood glucose,thyroid-stimulating hormone,thyroid hormone)between the two groups were compared to determine the risk factors for NAFLD.Secondly,all the subjects were divided into four groups according to the quartile of TSH,Q1 group(0.048 m IU/L～2.00 m IU/L),Q2 group(2.00 m IU/L～2.73 m IU/L),Q3 group(2.73 m IU/L～3.62 m IU/L),Q4 group(3.62 m IU/L～35.18 m IU/L),and the prevalence of NAFLD at different TSH levels was compared.Furthermore,the subjects were grouped by sex and the risk factors associated with NAFLD were explored in different sexes.The t-test was used for the comparison of the measurement data satisfying the normal distribution or approximately normal distribution,the Mann-Whitney U test was used for the comparison of the two groups of the measurement data with the skewed distribution,and the chi-square test was used for the comparison between the counting data groups.Finally,the variables with statistically significant differences between healthy people and men and women were included in the binary logistic regression to explore the correlation between them and NAFLD.Results:1.The proportion of men,age,weight,BMI,albumin,ALT,AST,GGT,TC,TG,LDL,fasting blood glucose and TSH were significantly higher in the NAFLD group than in the non-NAFLD group,while FT4 and HDL were lower than those in the non-NAFLD group(p value<0.05).There was no significant difference in height,T3,FT3 and T4 levels between the two groups(p value> 0.05).2.The results of binary logistic regression analysis of NAFLD showed that BMI(OR=1.291,95%CI: 1.179～1.415,P<0.001),TG(OR=1.843,95%CI: 1.306～2.601,P=0.001),SCH(OR=1.992,95%CI: 1.030～3.853,P=0.041),GGT(OR=1.013,95%CI :1.002～1.023,P=0.020)were independent risk factors for NAFLD.3.When the TSH levels of different quartiles were compared,when TSH <2.73 m IU/L,the prevalence of NAFLD between Q1 and Q2 groups was similar.When TSH > 2.73 m IU/L,the prevalence of NAFLD increased,the prevalence of NAFLD in the Q3 group was 1.25 times higher than that in the Q1 group,and the prevalence of NAFLD in the Q4 group was 1.32 times higher than that in the Q1 group,and with the increase of TSH levels,the prevalence of NAFLD in the Q4 group was 1.05 times higher than that in the Q3 group.However,there was no significant difference between the four groups(p value=0.084).4.The logistic regression analysis of female NAFLD showed that BMI(OR=1.346,95%CI: 1.188～1.525,P<0.001),TG(OR=1.794,95%CI: 1.053～3.058,P=0.032)were independent risk factors for female NAFLD,FT3(OR=0.452,95%CI:0.212～0.964,P=0.040),HDL(OR= 0.173,95%CI: 0.052～0.578,P=0.004)were its protective factors.5.The logistic regression analysis results of male NAFLD showed that BMI(OR=1.256,95%CI: 1.085～1.453,P=0.002),TSH(OR=1.436,95%CI: 1.029～2.005,P=0.033),GGT(OR=1.021,95%CI: 1.004～1.038,P=0.013)were independent risk factors for male NAFLD.HDL(OR=0.284,95%CI: 0.082～0.983,P=0.047)was its protective factor.Conclusion(s):1.SCH is a risk factor for the development of NAFLD.2.BMI and TG are independent risk factors for female NAFLD,while FT3 and HDL are its protective factors.3.BMI,TSH,and GGT are independent risk factors for male NAFLD,and HDL is its protective factor.4.BMI,TG,and GGT are independent risk factors for NAFLD.