Five risk factors were associated with unplanned readmission, including history of severe COPD (p = 0.030), CHF in 30 days before surgery (p = 0.004), dyspnea upon mild exertion (p = 0.008), as well as pre-operative serum albumin (p = 0.012) and hematocrit (p = 0.024). This evidence concerns the gene ALB and chronic obstructive pulmonary disease.