In a study, which used the largest sample of patients with COVID-19 and hypothyroidism till date, the researchers found that hypothyroidism was not associated with a worse prognosis among patients with COVID-19. The research using data collected by the Brazilian COVID-19 Registry, which includes 7,762 patients 37 from hospitals between March 1 and September 30, revealed that Covid-19 patients with underlying hypothyroidism were significantly less likely to require mechanical ventilation. Hospital mortality among these patients also tended to be less compared with patients with normal thyroid function. Patients with COVID-19 and hypothyroidism had similar comorbidities, clinical presentations, and laboratory values compared with patients without hypothyroidism. Of these patients, 526 had a clinical history of previously diagnosed hypothyroidism and were receiving levothyroxine replacement therapy at 31 of the participating hospitals in 15 Brazilian cities.The researchers matched these case patients with 526 control patients who had had COVID-19 and did not have a history of hypothyroidism. The findings suggest that underlying hypothyroidism does not lead to worse outcomes in patients with COVID-19.