FRI591 Association Of TSH Levels And NAFLD Severity In Children And Adolescents

Disclosure: M. Untalan: None. N.A. Crimmins: None. A. Mencin: None. K. Yates: None. X. Stavra: None. V. Thaker: None. Background: Non-alcoholic fatty liver disease (NAFLD) is characterized by hepatic lipid accumulation and is now the most common form of chronic liver disease in children and adolescents. Recent studies have indicated an association between subclinical hypothyroidism (SH) and NAFLD. An underactive thyroid gland produces insufficient T3 and T4 involved in hepatic fat metabolism that could contribute to NAFLD. While increased TSH has been documented in individuals with NAFLD, its independent role with NAFLD disease severity is yet to be clarified. Objective: To study the relationship of TSH levels and the severity of NAFLD/NASH, as well as determine whether changes in TSH levels are associated with changes in NAFLD/NASH among children. Methods: This retrospective study used data from two cohorts within the Nonalcoholic Steatohepatitis Clinical Research Network (NASH CRN). TSH, free and total T4, total T3, TPO antibodies and thyroglobulin (TBG) levels were assessed in samples obtained first at baseline and then at 52-96 weeks. Individuals with overt hypothyroidism, abnormal TPO antibody levels, and those receiving thyroid treatment were excluded from analysis. SH was defined as TSH > 4.4 mIU/L. Linear and multinomial regression models were used to identify the association between TSH, SH and NAFLD severity measured by NAFLD activity score (NAS), fibrosis stage, steatosis level, lobular and portal inflammation and ballooning while adjusting for potential confounders (sex, age, race, BMI-z, HOMA-IR and non-HDL levels). Longitudinal analysis was conducted by mixed-effects model. Analyses were performed with SAS and R statistical software. Results: 218 individuals and 421 observations were included in the cross-sectional and longitudinal analyses, respectively. Children with more severe grades of steatosis were more likely to be younger (p = 0.03) and male (p = 0.02). At baseline, TSH was not significantly associated with any NAFLD histological measures. Longitudinal analyses revealed a positive association of change in TSH and steatosis level after adjusting for covariates, and follow-up time (p = 0.03). Change in SH was associated with change in fibrosis stage (p = 0.01). Adding HOMA-IR and non-HDL levels to the models did not change this relationship. The positive relationship of total T3 and T4 with NAS was explained by TBG. Conclusion: In a large cohort of pediatric patients with biopsy-confirmed NAFLD, high TSH levels correlated with increasing steatosis grade and NAS, and SH with increased liver fibrosis. Markers of impaired thyroid function may help predict disease severity in pediatric patients with NAFLD. Presentation: Friday, June 16, 2023