Among them, Sahin et al. showed that age, presence of diabetes mellitus, asthma/chronic obstructive pulmonary disease (COPD), heart failure, chronic kidney disease, prior coronary artery disease, renin–angiotensin–system blocker usage and low lymphocyte were positively associated with mortality in patients with TC and COVID-19 infection. This evidence concerns the gene REN and chronic obstructive pulmonary disease.