Significantly higher ghrelin and NPY levels in the fasting condition were observed in the COVID-19 group than in the non-COVID-19 group (197.5 pg/mL vs. 67.1 pg/mL, p < 0.001 for ghrelin and 128.0 pg/mL vs. 84.5 pg/mL, p = 0.005; Table 3). The gene discussed is GHRL; the disease is COVID-19.