Researchers have discovered in a new study that abnormal serum thyroid hormone levels are independently correlated with a higher risk of metabolic steatohepatitis (MASH) in patients with normal thyroid function. The findings suggest a possible role of thyroid hormones as biomarkers for the identification of patients at greater risk of MASH. Metabolic steatohepatitis is a severe liver disease frequently associated with the wider spectrum of non-alcoholic fatty liver disease (NAFLD). The study was conducted by Chun-Yan Yang and fellow researchers published in the journal Digestive and Liver Disease.MASH is a progressive type of fatty liver disease that may result in liver fibrosis, cirrhosis, and even liver cancer if not treated. Although various metabolic abnormalities such as obesity and insulin resistance are well-documented to contribute, the possible role of thyroid hormone disturbances in those without clinical thyroid disease has gained more interest. Thyroid hormones have a central role in lipid metabolism and liver function regulation. Knowing that their connection to MASH would provide new doors for risk evaluation and early intervention in NAFLD at-risk individuals.The study retrospectively enrolled 638 patients with NAFLD hospitalized from March 2021 to March 2024. Patients were allocated into two groups according to liver biopsy diagnosis by expert pathologists: 262 patients in the MASH group and 376 patients in the non-MASH group. Clinical information, such as serum concentrations of thyroid-stimulating hormone (TSH), free triiodothyronine (FT3), and free thyroxine (FT4), were obtained. Multivariate logistic regression analysis was conducted to determine independent correlations between thyroid hormone concentrations and the occurrence of MASH. Receiver operating characteristic (ROC) curves were also employed to evaluate the predictive value of these hormone concentrations for the diagnosis of MASH.Key FindingsNumber of patients studied: 638MASH group: 262 patientsNon-MASH group: 376 patientsSerum TSH concentration: Higher in MASH group (AUC 0.944)Serum FT3 concentration: Higher in MASH group (AUC 0.973)Serum FT4 concentration: Lower in MASH group (AUC 0.753)FT3/FT4 ratio: Higher in MASH group (AUC 0.959)Independent predictors of MASH: TSH, FT3, FT4This research concluded that high serum TSH and FT3 levels, increased FT3/FT4 ratio, and low FT4 levels were independently related to a greater risk for metabolic steatohepatitis in euthyroid patients. These findings emphasize the significance of identifying subtle changes in thyroid hormones even in the euthyroid group as the most important point for the development of liver disease.Reference:Yang, C.-Y., Guan, W., Liu, Y., & Zhang, P. (2025). Correlation between serum thyroid hormone level and metabolic steatohepatitis: A retrospective study. Digestive and Liver Disease: Official Journal of the Italian Society of Gastroenterology and the Italian Association for the Study of the Liver. https://doi.org/10.1016/j.dld.2025.03.006