Endocrine Abstracts

Introduction: Non-Thyroidal Illness Syndrome (NTIS) is characterized by decreased serum concentration of thyroid hormones – typically free triiodothyronine (FT3). This adaptive response has been commonly observed in critically ill patients, including those with COVID-19. This study investigates the prevalence of thyroid hormone abnormalities in COVID-19 patients and their association with disease mortality.

Methods: We conducted a retrospective analysis of 846 patients hospitalized due to COVID-19 at the Regional Hospital in Słupca, wielkopolskie, Poland, between January and April 2021. We selected 137 patients, based on the availability of serum concentration measurements of thyroid-stimulating hormone (TSH), free thyroxine (FT4), FT3, and vitamin D on admission. Descriptive statistics and univariate logistic regression analysis were performed to evaluate relationship between study variables and COVID-19 mortality.

Results: Decreased levels of FT3, FT4, and TSH were observed in 21.17%, 24.82%, and 64.23% of patients. Age emerged as a significant predictor of mortality (OR=1.07, P = 0.014), while TSH (OR=0.78, P = 0.448), FT4 (OR=1.69, P = 0.385), FT3 (OR=0.76, P = 0.395), and vitamin D (OR=1.01, P = 0.584) showed no significant associations.

Conclusion: We highlight the common occurrence of thyroid hormone abnormalities in the acute phase of COVID-19. However, our findings suggest that thyroid hormone concentrations do not reliably predict COVID-19 mortality, which contrasts with some previous studies. Further research is needed to explore the relationship between thyroid hormone alterations, the disease course of COVID-19, and its clinical implications.