It is worth noting that compared with young-old COVID-19 patients, dyspnea symptoms, PH, PaO2/FiO2, heart rate, INR, cardiac troponin I, acute cardiac injury, white blood cell count, neutrophil count, platelet count, albumin, critical illness, chronic kidney disease, combined diabetes, and glucocorticoid therapy factors were only associated with death in old-old patients. This evidence concerns the gene TNNI3 and diabetes mellitus.