ALB and chronic obstructive pulmonary disease: In the present real-world study, BMI, serum albumin, and pulmonary functions including VC, FVC, FEV1.0, FEV1.0/FVC, %FEV1.0, and DLco were significantly lower, and the cardiovascular disease comorbidity rate, COPD assessment test score, mMRC dyspnea scale, and use of long-term oxygen therapy, LABAs, ICS, and macrolides were significantly higher in COPD patients who experienced exacerbations than in COPD patients who never experienced severe exacerbations.