OBJECTIVE: Precise risk stratification and triage of coronavirus disease 2019 (COVID-19) patients are essential in the setting of an overwhelming pandemic burden . Clinical observation has shown a somewhat high prevalence of sick euthyroid syndrome among patients with COVID-19 . This study aimed to evaluate the predictive value of free triiodothyronine (FT3) at the clinical presentation of COVID-19 for disease severity and death .
METHODS: This retrospective cohort study was based on electronic medical records . The study was conducted at Sheba Medical Centre, a tertiary hospital where several acute and chronic wards have been dedicated to the treatment of patients with COVID-19 . The primary outcome measure was death during hospitalization; secondary outcomes included hospitalization in intensive care, mechanical ventilation, and length of hospitalization .
RESULTS: Of a total of 577 polymerase chain reaction-positive patients with COVID-19 hospitalized between February 27 and July 30, 2020, 90 had at least 1 measurement of thyroid-stimulating hormone, free thyroxine, and FT3 within 3 days of presentation . After applying strict exclusion criteria, 54 patients were included in the study . Patients in the lowest tertile of FT3 had significantly higher rates of mortality (40% , 5.9%, and 5.9%, P = .008), mechanical ventilation (45% , 29.4%, and 0.0% ; P = .007) and intensive care unit admission (55% , 29.4%, and 5.9%, P = .006). In multivariate analyses adjusted for age, Charlson comorbidity index, creatinine, albumin, and white blood cell count . FT3 remained a significant independent predictor of death .
CONCLUSION: FT3 levels can serve as a prognostic tool for disease severity in the early presentation of COVID-19.