Low FT3 is an independent marker of disease severity in patients hospitalized for COVID-19.

Aim: To study the prevalence of thyroid dysfunction and its association with disease severity in hospitalized patients of coronavirus disease-19 (COVID-19).

Methods: In this retrospective cohort study, thyroid function tests (TFT) of 236 hospitalized patients of COVID-19 along with demographic, comorbid, clinical, biochemical and disease severity records were analysed. Patients were divided into previous euthyroid or hypothyroid status to observe the effect of prior hypothyroidism on the severity of COVID-19.