GCG and COVID-19: Other endocrine biomarkers (EBs), such as cortisol, C-peptide, glucagon-like peptide-1 (GLP-1), insulin, and peptide YY (PYY), appear to be associated with clinical outcomes in hospitalized patients with COVID-19.(15-19) Serum cortisol levels appear to be an independent predictor of unfavorable outcomes, and there is an apparent association between other metabolic markers and inflammation modulatory pathways in patients with COVID-19.(15-19)