Correlation of thyroid hormones with lactate Dehydrogenase activity

Background and Aim: Thyroid hormones regulate the rate of metabolic activity and their alterations can perturb the activity of serum enzymes. The aim of this study was to determine the activity of serum Lactate dehydrogenase (LDH) in thyroid disorders and to evaluate the relationship between LDH and T3, T4, and TSH levels. Design and Methods: In this study, thyroid function tests (T3, T4 and TSH) and LDH activity was assessed in 359 individuals divided into four groups based on TSH levels as having normal TSH (group 1), Clinical hyperthyroidism (group 2), Sub clinical hypothyroidism (group 3) and clinical hypothyroidism (group 4). Statistical analysis: Data collected was presented as mean± S.D; Pearson’s coefficient of correlation was calculated to study the correlation between different parameters. Results: No change in LDH activity was observed in hyperthyroid state, however in sub clinical and clinical hypothyroid individuals it showed significant change at (p≤0.001) as compared to normal individuals but no significant correlation was found between thyroid hormones, TSH and LDH activity in any of the studied group. Conclusions: With no significant correlation observed between LDH activity and T3, T4 and TSH in any thyroid disorder state, LDH activity we may not use as a direct parameter to assess the thyroid dysfunction.