Seven independent predictors of COPD complicated by T2DM were identified: arterial partial pressure of carbon dioxide (PCO2) (OR = 1.04, 95%CI: 1.02–1.05), neutrophil number (NEUT) (OR = 1.15, 95%CI: 1.10–1.19), C-reactive protein (CRP) (OR = 1.01, 95%CI: 1.01–1.02), erythrocyte sedimentation rate (ESR) (OR = 1.03, 95%CI: 1.02–1.05), bilirubin (OR = 0.92, 95%CI: 0.88–0.96), triglyceride (TG) (OR = 1.33, 95%CI: 1.13–1.56), and body mass index (BMI) (OR = 1.16, 95%CI: 1.11–1.20). Here, CRP is linked to chronic obstructive pulmonary disease.