Table 1 shows the baseline characteristics of patients with T-COPD and S-COPD. The patient-reported scores for symptoms and quality of life were similar in both groups, except for the St. George Respiratory Questionnaire (SGRQ) score, which was higher in the T-COPD group than in the S-COPD group. The rate of FEV1 decline and the percentage of acute exacerbations did not show significant differences among the groups. C-reactive protein (CRP) levels, erythrocyte sedimentation rate (ESR), and IL-6 levels were significantly higher in patients with T-COPD than in those with S-COPD (Table 1). Here, IL6 is linked to chronic obstructive pulmonary disease.