Thyroid Function Abnormalities in the Acute Phase of COVID-19: A Cross-Sectional Hospital-Based Study From North India

Post-COVID Syndrome and Severity of COVID-19: A Cross-Sectional Epidemiological Evaluation From North India

Background

COVID-19 has now lasted for more than two years as a pandemic and has had enduring effects on the health of people as the post-COVID syndrome. Recent literature has shown the long-term effects of COVID‐19 on various organ systems, including but not limited to respiratory, cardiovascular, neurological, musculoskeletal, and gastrointestinal systems.

Methods and objectives

We aimed to estimate the prevalence of post-acute COVID symptoms in a tertiary care center in northern India; observe the effects of the demographic profile of age, BMI, gender, and presence of comorbidities on the persistence of post-COVID syndrome, and explore any correlation between the severity of COVID-19 disease and the persistence of post-COVID symptoms. We designed a survey containing structured questions evaluating post-COVID symptoms beyond three weeks (post-acute COVID phase), six weeks (post-COVID phase), and 12 weeks of acute illness. It was administered online. 

Results

Prevalence of post-COVID symptoms both after three and six weeks was reported to be 16.67% and 7.37%, respectively. The most common symptoms to persist were musculoskeletal symptoms (fatigue), followed by upper respiratory symptoms. Disease severity (p<0.05), BMI (p<0.05), and comorbidities were seen to affect post-COVID symptoms significantly, whereas gender and age of the patient had no significant effect. Disease severity significantly affected the persistence of post-COVID symptoms up to 12 weeks; however, this effect does not hold true in long COVID haulers. Also, the risk of developing persistent post-acute COVID symptoms was more in moderate to severe disease than in mild disease.

Conclusion

The pandemic might be close to over, but it is not out of our lives yet, and the persistence of post-COVID symptoms is exigent.

COVID-19 and thyroid function: What do we know so far?

Coronavirus disease 2019 (COVID-19) was characterized as a pandemic in March, 2020 by the World Health Organization. COVID-19 is a respiratory syndrome that can progress to acute respiratory distress syndrome, multiorgan dysfunction, and eventually death. Despite being considered a respiratory disease, it is known that other organs and systems can be affected in COVID-19, including the thyroid gland. Thyroid gland, as well as hypothalamus and pituitary, which regulate the functioning of most endocrine glands, express angiotensin-converting enzyme 2 (ACE2), the main protein that functions as a receptor to which SARS-CoV-2 binds to enter host cells. In addition, thyroid gland is extremely sensitive to changes in body homeostasis and metabolism. Immune system cells are targets for thyroid hormones and T3 and T4 modulate specific immune responses, including cell-mediated immunity, natural killer cell activity, the antiviral action of interferon (IFN) and proliferation of T- and B-lymphocytes. However, studies show that patients with controlled hypothyroidism and hyperthyroidism do not have a higher prevalence of COVID-19, nor do they have a worse prognosis when infected with the virus. On the other hand, retrospective observational studies, prospective studies, and case reports published in the last two years reported abnormal thyroid function related to acute SARS-CoV-2 infection or even several weeks after its resolution. Indeed, a variety of thyroid disorders have been documented in COVID-19 patients, including non-thyroidal illness syndrome (NTIS), subacute thyroiditis and thyrotoxicosis. In addition, thyroid disease has already been reported as a consequence of the administration of vaccines against SARS-CoV-2. Overall, the data revealed that abnormal thyroid function may occur during and in the convalescence post-COVID condition phase. Although the cellular and molecular mechanisms are not completely understood, the evidence suggests that the "cytokine storm" is an important mediator in this context. Thus, future studies are needed to better investigate the pathophysiology of thyroid dysfunction induced by COVID-19 at both molecular and clinical levels.