In this study, we took elderly (age > 70 years), body mass index > 30, smoking, diabetes mellitus, coronary artery disease, chronic obstructive pulmonary disease, anemia, low serum albumin, operation time > 3h, and perioperative blood loss > 500 ml as the risk factors for SSI and found that 18 patients (85.7%) had at least one of the above risk factors. This evidence concerns the gene ALB and chronic obstructive pulmonary disease.