Correlation between inflammatory parameters and pituitary-thyroid axis in patients with COVID-19.

In this cohort, thyroid hormones correlated with inflammation and outcome. T3 and T3/T4 correlated inversely with inflammatory markers; a low T3/T4 ratio was associated with severity and poor prognosis. Patients with low T3 but high FT4 had higher ferritin, lower albumin, and more severe disease at presentation.