Rates ofare significantly higher among patients who are critically ill with COVID-19 than among patients who are critically ill but who do not not have COVID-19, suggesting an atypical form of related to the novel coronavirus infection, according to new research.
“We suggest routine assessment of thyroid function in patients with COVID-19 requiring high-intensity care because they frequently present with thyrotoxicosis due to a form ofrelated to SARS-CoV-2,” the authors wrote in correspondence in The Lancet Diabetes and Endocrinology.
However, notably, the study – which compared critically ill ICU patients who had COVID-19 with those who did not have COVID-19 or who had milder cases of COVID-19 – indicates that thyroid disorders do not appear to increase the risk of developing COVID-19, first author Ilaria Muller, MD, PhD, of the department of endocrinology, IRCCS Fondazione Ca’ Granda Ospedale Maggiore Policlinico, Milan, said in an interview.
“It is important to highlight that we did not find an increased prevalence of preexisting thyroid disorders in COVID-19 patients (contrary to early media reports),” she said. “So far, clinical observations do not support this fear, and we need to reassure people with thyroid disorders, since such disorders are very common among the general population.”
Yet the findings add to emerging evidence of a COVID-19/thyroid relationship, Angela M. Leung, MD, said in an interview.
“Given the health care impacts of the current COVID-19 pandemic worldwide, this study provides some insight on the potential systemic inflammation, as well as thyroid-specific inflammation, of the SARS-Cov-2 virus that is described in some emerging reports,” she said.
“This study joins at least six others that have reported a clinical presentation resembling subacute thyroiditis in critically ill patients with COVID-19,” noted Dr. Leung, of the division of endocrinology, diabetes, and metabolism in the department of medicine at the University of California, Los Angeles.
Thyroid function analysis in those with severe COVID-19
Dr. Muller explained that preliminary data from her institution showed thyroid abnormalities in patients who were severely ill with COVID-19. She and her team extended the evaluation to include thyroid data and other data on 93 patients with COVID-19 who were admitted to high-intensity care units (HICUs) in Italy during the 2020 pandemic.
Those data were compared with data on 101 critically ill patients admitted to the same HICUs in 2019 who did not have COVID-19. A third group of 52 patients with COVID-19 who were admitted to low-intensity care units (LICUs) in Italy in 2020 were also included in the analysis.
The mean age of the patients in the HICU 2020 group was 65.3 years; in the HICU 2019 group, it was 73 years; and in the LICU group, it was 70 years (P = .001). In addition, the HICU 2020 group included more men than the other two groups (69% vs. 56% and 48%; P = .03).
Of note, only 9% of patients in the HICU 2020 group had preexisting thyroid disorders, compared with 21% in the LICU group and 23% in the HICU 2019 group (P = .017).
These findings suggest that “such conditions are not a risk factor for SARS-CoV-2 infection or severity of COVID-19,” the authors wrote.
The patients with the preexisting thyroid conditions were excluded from the thyroid function analysis.
A significantly higher proportion of patients in the HICU 2020 group (13; 15%) were thyrotoxic upon admission, compared with just 1 (1%) of 78 patients in the HICU 2019 group (P = .002) and one (2%) of 41 patients in the LICU group (P = .025).
Among the 14 patients in the two COVID-19 groups who had thyrotoxicosis, the majority were male (9; 64%)
Among those in the HICU 2020 group, serum thyroid-stimulating hormone concentrations were lower than in either of the other two groups (P = .018), and serum free(free T4) concentrations were higher than in the LICU group (P = .016) but not the HICU 2019 group.