Evaluation of the Characteristics of Asthma in Severe and Extremely Severe COPD

BACKGROUND: Biotherapy for asthma may be useful in patients suffering from chronic obstructive pulmonary disease (COPD) with asthma characteristics. Therefore, the evaluation and close monitoring of asthma characteristics in severe and extremely severe COPD can guide treatment decisions to improve prognosis. METHODS: Stable patients suffering from COPD and having a forced expiratory volume in 1 s (FEV(1)%) of ≤50% (GOLD 3–4) in the First Affiliated Hospital of Sun Yat-Sen University from December 2014 to June 2018 were retrospectively enrolled in this study and evaluated in terms of their asthma characteristics (blood eosinophil counts, fractional exhaled NO [FeNO] values, and reversibility). RESULTS: A total of 178 patients with an average age of 65.62±9.28 years were enrolled in this study. A total of 85 patients had an improvement of ≥12% in FEV(1)%, and 61 of these patients had an absolute increase of >200 mL. Of 122 patients, 68 had blood eosinophil counts of ≥150 cells/μl, whereas 27 showed blood eosinophil counts ≥300 cells/μl. The blood eosinophil of ≥2% was found in 66/122 (54.10%) patients, whereas ≥3% was found in 51/122 (41.80%) patients. A total of 46 of 58 patients had an increased serum IgE level of ≥30 IU/mL, and 32 patients had an IgE of ≥100 IU/mL. The FeNO value of ≥25 ACO (ppb) was found in 51/155 (32.90%) patients. Furthermore, 43 patients had asthma–COPD overlap (ACO), and the FeNO values in the ACO group was 26.13±14.91 ppb, which was significantly higher than that in the COPD alone group (20.99±9.16 ppb; P=0.016). A total of 12 patients with ACO had a negative response after bronchodilation. In the COPD alone group, 34 patients had an absolute increase of >200 mL, whereas 55 of the 95 patients had blood eosinophil counts of ≥150 cells/μl. The blood eosinophilia of ≥2% was found in 54/95 (56.84%) patients. A total of 36 of 45 patients had an increased serum IgE level of ≥30 IU/mL. The FeNO value of 34/123 (27.64%) patients was ≥25 ppb. CONCLUSION: The characteristics of asthma are common findings in patients with severe and extremely severe COPD. Biomarkers should be actively used to evaluate the characteristics of asthma in these patients. If the characteristics of asthma exist, then anti-IgE or anti-IL-5 therapy should be considered to reduce exacerbation.