Impact of Hyperthyroidism on Liver Function: A Study of Serum Enzyme Variations

Abstract

Hyperthyroidism is a clinical disorder marked by the excessive production and release of thyroid hormones by an overactive thyroid gland, leading to a hypermetabolic state that affects multiple organ systems, including the liver. This study aims to assess the serum ALT, AST, ALP, and GGT in patients with Hyperthyroidism. This cross-sectional study was conducted between January 1 and July 10, 2025, at Alshams Medical Laboratories in Diyala City. It included 100 participants: 70 patients with Hyperthyroidism and 30 healthy controls. Serum pituitary and thyroid hormone levels were measured using the cobas® e 411 analyzers, while liver enzymes were analyzed with a cobas® c 311 analyzer. Serum ALT, AST, and ALP were significantly higher in hyperthyroid compared to controls (P= 0.001 for all). Although GGT levels were slightly higher in the patient group than in controls, the difference did not reach statistical significance (P=0.274). ALP showed a significant negative correlation with TSH (P=0.038), and significant moderate positive correlations with Free T3 (P=0.003 and Free T4 (P=0.042). Hyperthyroid patients show elevated liver enzymes, with ALP inversely related to TSH and positively to Free T3 and T4. This may signal potential liver dysfunction and calls for further evaluation among these patients.