Fig. 1

R-Xc (resistance versus reactance) graphs of bioelectrical impedance vector analysis data of patients with COVID-19 compared to non-COVID-19 thyroid patients. Red stars indicate individual measurement at admission. The 95%, 75% and 50% tolerance ellipses are shown. The lower axis (c) indicates cellularity (above, to the left, indicate more body cell mass and below, to the right, less body cell mass), while the largest axis (h) indicates hydration (dehydration towards the upper pole, hyperhydration with apparent edema toward the lower pole). a Non COVID-19 control patients (n. 95); b COVID-19 patients (n. 74); c COVID-19 patients with FT3 serum values > 1.7 pg/ml (n. 32); d COVID-19 patients with FT3 serum values ranging from 1.1 to 1.7 pg/ml (n. 29); e COVID-19 patients with FT3 serum values < 1.1 pg/ml (n. 13)