Benefits of Levothyroxine Replacement Therapy on Nonalcoholic Fatty Liver Disease in Subclinical Hypothyroidism Patients

Abstract

<i>Objectives</i>. To evaluate the effect of levothyroxine (LT₄) replacement therapy on nonalcoholic fatty liver disease (NAFLD) in subclinical hypothyroidism (SCH) patients. <i>Methods</i>. This study was a post hoc analysis of a randomized controlled trial and involved 33 significant and 330 mild SCH patients. All of the significant SCH patients received LT₄ supplement. The mild SCH patients were grouped as LT₄ treated or not. After 15 months of follow-up, prevalence of NAFLD in each group was reevaluated. Subgroup analysis was conducted in mild SCH patients with dyslipidemia. <i>Results</i>. After treatment with LT₄, the prevalence of NAFLD in significant SCH patients reduced from 48.5% to 24.2% (<i>p</i> = 0.041). In mild SCH patients, prevalence of NAFLD and serum alanine aminotransferase (ALT) was not significantly affected by LT₄ supplementation. Nonetheless, mild SCH patients with dyslipidemia who received LT₄ treatment experienced decreases in the prevalence of NAFLD and serum ALT levels (<i>p</i> < 0.05 for both). In contrast, these parameters remained comparably stable in patients who were not treated. <i>Conclusion</i>. LT₄ supplementation has benefits on NAFLD in significant SCH patients or mild SCH patients with dyslipidemia. For NAFLD patients with SCH, appropriate supplementation of LT₄ may be an effective means of controlling NAFLD. The original trial was registered with ClinicalTrials.gov (NCT01848171).