Chronic Obstructive Pulmonary Disease Patients With High Peripheral Blood Eosinophil Counts Have Better Predicted Improvement in 6MWD After Rehabilitation

Purpose: The objective of this investigation was to determine whether chronic obstructive pulmonary disease (COPD) patients with high blood eosinophil (EOS) counts had better improvement in 6-min walk test (6MWT) after pulmonary rehabilitation (PR). Methods: Fifty COPD patients were randomly assigned to either the rehabilitation group (RG) or the control group (CG). Patients in the RG (8 wk PR + routine medication) and the CG (routine medication) were followed for 32 wk. According to the blood EOS level, the RG was divided into an EOS ≥ 200 cells/μL group and EOS < 200 cells/μL group. The 6MWT distance, Borg Scale, and COPD Assessment Test (CAT) were evaluated before intervention and 8 wk and 32 wk later. Results: After the 8-wk intervention, 37 patients (19 RG/18 CG) completed the study. At 8-wk and 32-wk follow-up from baseline, a statistically significant difference was found between these two groups in the 6MWT, Borg Scale, and CAT. Compared with baseline, the 6MWT in the RG increased 49.1 ± 40.2 m (95% CI, 29.7-68.5, P < .001) at 8 wk and 60.8 ± 42.1 m (95% CI, 40.5-81.6, P < .001) at 32 wk. In addition, the improvement of 6MWT in the EOS ≥ 200 cells/μL RG group was higher than that in the EOS < 200 cells/μL group (40.1 ± 17.6 m, 95% CI, 36.8-43.4; P = .036) at 32-wk follow-up from baseline. Conclusion: An 8-wk PR can improve the exercise capacity of COPD patients, and the benefits persistent for 24 wk. The improvement in the 6MWT was more significant in COPD patients with a high blood EOS count.