The following are the risk factors for POP in geriatric patients with hip fractures: advanced age, male sex, ASA classification ≥3, dependent functional status, history of smoking, COPD, DM, CHD, arrhythmia, CVA, dementia, CRF, hip arthroplasty, delayed surgery, increased preoperative Cr, and decreased preoperative Alb. This evidence concerns the gene ALB and chronic obstructive pulmonary disease.