LEP and COVID-19: Leptin levels were higher in the plasma from severe and critical COVID-19 patients during the second wave, [8.4; IQR 3.3–16.9] compared to the first wave [17.4; IQR 7.9–40.0] for severe, and [9.5; IQR 5.9–51.0] compared to [4.0; IQR 1.9–9.6] for critical COVID-19 patients.