Biochemical and metabolic alterations in liver function associated with thyroid dysfunction: a comparative clinical study, Біохімічні та метаболічні зміни функції печінки, пов’язані з дисфункцією щитоподібної залози: порівняльне клінічне дослідження

<jats:p>Background. Thyroid hormones are essential regulators of systemic metabolic homeostasis, particularly lipid metabolism and hepatic function. Thyroid dysfunction, including hyperthyroidism and hypothyroidism, is commonly associated with biochemical and metabolic disturbances that may increase the risk of liver dysfunction and dyslipidemia. Despite the clinical relevance of these alterations, their patterns and extent remain insufficiently characterized, especially in populations with a high prevalence of thyroid disorders. The purpose was to evaluate biochemical and metabolic alterations in liver function and lipid profile associated with thyroid dysfunction and to compare these changes among hyperthyroid, hypothyroid, and healthy individuals. Materials and methods. A case-control study was conducted on 120 participants divided into two groups: hyperthyroid patients (n = 60), hypothyroid patients (n = 60); also, there was a group of apparently healthy controls (n = 30). Thyroid function was assessed by measuring serum levels of thyroid-stimulating hormone, triiodothyronine, and thyroxine. Liver function was evaluated using alanine aminotransferase (ALT), aspartate aminotransferase (AST), alkaline phosphatase (ALP), and gamma-glutamyl transferase (GGT). Lipid profile parameters, including total cholesterol, triglycerides, low- and high-density lipoprotein, were also analyzed. Statistical analysis was performed with a significance threshold of P ≤ 0.05. Results. Distinct thyroid hormone profiles were observed among the study groups. Hyperthyroid patients showed significantly eleva­ted ALP, ALT, and GGT levels compared to hypothyroid and control groups (P ≤ 0.05), indicating increased hepatic involvement. AST levels were higher in hyperthyroidism but without statistical significance. In contrast, hypothyroid patients exhibited significantly increased total cholesterol and triglyceride levels, reflecting impaired lipid metabolism. Conclusions. Thyroid dysfunction is associated with significant biochemical and metabolic alterations affecting liver enzymes and lipid homeostasis. Routine monitoring of hepatic and lipid parameters in patients with thyroid disorders is recommended to reduce the risk of metabolic and hepatic complications.</jats:p>