Frequency and Impact of Thyroid Hormone Abnormalities in COVID-19: An Observational Study at the Peak of the Pandemic
Paweł Komarnicki, Alicja Rajewska, Jolanta Tomczak, Elżbieta Wrotkowska, Zbigniew Krasiński, Marek RuchałaBackground:
COVID-19, caused by SARS-CoV-2, affects multiple organ systems, including the thyroid gland. Non-Thyroidal Illness Syndrome (NTIS) is frequently observed in severe systemic disease. NTIS-like thyroid hormone alterations have previously been reported in COVID-19. However, the relationship between these changes and disease outcomes remains unclear.
Objectives:
We aimed to evaluate thyroid function and vitamin D concentrations in hospitalized COVID-19 patients, and to analyze the association between hormonal measurements and patient characteristics with COVID-19 mortality.
Methods:
We conducted a retrospective database search of 846 adult patients hospitalized in a dedicated COVID-19 hospital at the peak of the pandemic. Based on the availability of serum levels of TSH, FT3, FT4, and vitamin D, 137 patients were included in the analysis. Descriptive statistics, comparative analyses, and logistic regression were used to evaluate the associations of laboratory measurements, sex, and age with COVID-19 mortality.
Results:
Decreased thyroid hormone and vitamin D concentrations were more common than in the general population, although none differed between deceased and COVID-19 survivors. Among the cohort, 63.5% had decreased TSH, 21.2% had decreased FT3, 24.1% had decreased FT4, and 75.9% presented with vitamin D deficiency. Comparative analyses showed no significant differences in TSH (
Conclusions:
NTIS-like thyroid hormone alterations and vitamin D deficiency are highly prevalent among hospitalized COVID-19 patients but do not predict in-hospital mortality. Age remains the major risk factor for death in this population. Our findings confirm that COVID-19 frequently affects the endocrine system and highlight the need for further research on long-term thyroid outcomes.