EVALUATION OF THYROID FUNCTION AND ITS ASSOCIATION WITH SEVERITY IN PATIENTS WITH CHRONIC LIVER DISEASE

Abstract

Background: The liver is the most biochemically complex organ. It is necessary for the metabolism, elimination, detoxification, and storage of hazardous chemicals. Since the liver is the primary organ involved in the peripheral conversion of tetraiodothyronine (T4) to triiodothyronine (T3) by Type 1 deiodinase, which leads to the 5-deiodination of T4, it contributes significantly to thyroid hormone metabolism. Materials and Methods: This is an observational case–control study that included clinically diagnosed cases of chronic liver disease 50 and 50 healthy individuals. Serum FT3, FT4, and thyroid‑stimulating hormone (TSH) levels were measured using chemiluminescent immunoassay (CLIA), and results were also analysed for severity of liver disease according to Child–Turcotte–Pugh (CTP) (Class A, B, and C), and model for end‑stage liver disease (MELD) scores. Results: Chronic liver disease patients had statistically significantly lower levels of FT3 (P < 0.0001) and had higher levels of TSH (P < 0.0001) compared with the controls. Overall, the mean FT3 levels were significantly lower in cases as compared to controls, while the mean FT4 levels in cases were marginally lower than those in controls, and TSH levels were significantly elevated in cases compared to controls. A decrease in FT3 levels was observed with an increasing CP Score of Chronic Liver Disease; i.e., CP Score A had the highest mean FT3 levels, while in MELD scoring, the highest percentage of cases, i.e., lowest severity, were in the ≤ 9 category (52%). Conclusion: The mean FT3 levels were significantly decreased, and the mean TSH levels were significantly increased in chronic liver disease patients compared to healthy controls. The levels of FT3, FT4, and TSH also correlate with the severity of liver disease; the level of FT3 can be used as a prognostic marker for liver cirrhosis patients.