Abstract
CONTEXT: We assessed the association between the severity of COVID-19 and the thyroid function, and the relationship of thyroid hormones with inflammatory markers in COVID-19 patients. SUBJECTS AND METHODS: This observational study contained 95 COVID-19 patients. The covariates of interest included the thyroid-stimulating hormone (TSH) and the total form of thyroid hormones thyroxine and triiodothyronine. Furthermore, the inflammatory markers including C-reactive protein, erythrocyte sedimentation rate, lactate dehydrogenase (LDH), and lymphocyte were measured. To analyze the data, the t-test, the nonparametric test for comparing the medians, and the Spearman correlation were used. RESULTS: The median (interquartile range) of ages was equal to 53 (41-66) years old, including 54 men (56.8%). As the severity of COVID-19 progressed from moderate to severe, increasing, though non-significant, trends of thyroid dysfunction were observed, the most remarkable for TSH. The only significant association between thyroid hormones and inflammatory markers was a Spearman correlation of -0.28 between TSH and LDH. Moreover, a direct association was found between the severity of COVID-19 and the LDH levels (p-value<0.001). CONCLUSIONS: A direct relation between the severity of COVID-19 and the LDH level and a reverse association between the LDH level and the thyroid hormone, TSH was obtained.