Association of blood eosinophils and plasma periostin with FEV1 response after 3-month inhaled corticosteroid and long-acting beta(2)-agonist treatment in stable COPD patients

Background: COPD patients with increased airway eosinophilic inflammation show a favorable response to inhaled corticosteroids (ICS) in combination with a long-acting bronchodilator. Recent studies have demonstrated a significant correlation of sputum eosinophilia with blood eosinophils and periostin. We investigated whether high blood eosinophils and plasma periostin were associated with an improvement in forced expiratory volume in 1 second (FEV1) after 3-month treatment with ICS/long-acting beta(2)-agonist (LABA) in stable COPD patients. Patients and methods: Blood eosinophils and plasma periostin levels were measured in 130 stable COPD subjects selected from the Korean Obstructive Lung Disease cohort. Subjects began a 3-month ICS/LABA treatment after washout period. Results: High blood eosinophils (>260/mu L, adjusted odds ratio=3.52, P=0.009) and high plasma periostin (>23 ng/mL, adjusted odds ratio=3.52, P=0.013) were significantly associated with FEV1 responders (>12% and 200 mL increase in FEV1 from baseline after treatment). Moreover, the addition of high blood eosinophils to age, baseline positive bronchodilator response, and FEV1,50% of the predicted value significantly increased the area under the curve for prediction of FEV1 responders (from 0.700 to 0.771; P=0.045). Conclusion: High blood eosinophils and high plasma periostin were associated with improved lung function after 3-month ICS/LABA treatment. In particular, high blood eosinophils, in combination with age and baseline lung function parameters, might be a possible biomarker for identification of COPD patients with favorable FEV1 improvement in response to ICS/LABA treatment.We thank Su-Young Kim and the following members of the Korean Obstructive Lung Disease (KOLD) Study Group for the generous provision of data and samples: Tae Rim Shin, Sang Yeub Lee, Ho Il Yoon, Seung Soo Sheen, Jin Hwa Lee, Joo Hun Park, Yong Bum Park, Chin Kook Rhee, Changhwan Kim, Yong Il Hwang, Kwang Ha Yoo, Young Sam Kim, Ji Ye Jung, Yoon ki Hong, Seung Won Ra, Joon Beom Seo, Sang Min Lee, Chang Hoon Lee, Sei Won Lee, Jae Seung Lee, Ji-Hyun Lee, Eun Kyung Kim, Jin Won Huh, Ji Yong Moon, Hyoung Kyu Yoon, Hye Kyeong Park, Jin Woo Kim, Kang Hyeon Choi, Joo Ock Na, Doh Hyung Kim, Hye Sook Choi, Kwang Ha Lee, Myung Jae Park, and Sung Soon Lee. The KOLD Study was supported by a grant from the Korean Health 21 R&D Project, Ministry of Health and Welfare, Republic of Korea (HI10C2020 and A102065). This study was supported by Samsung Medical Center Foundation for Medical Research (SMO1140211)