Blood eosinophil count as a prognostic biomarker in COPD

• Published in: International journal of chronic obstructive pulmonary disease Vol. 13; pp. 3589 - 3596
• Main Authors: Oh, Yeon-Mok, Lee, Keu Sung, Hong, Yoonki, Hwang, Sung Chul, Kim, Jae Yeol, Kim, Deog Keom, Yoo, Kwang Ha, Lee, Ji-Hyun, Kim, Tae-Hyung, Lim, Seong Yong, Rhee, Chin Kook, Yoon, Hyoung Kyu, Lee, Sang Yeub, Park, Yong Bum, Jung, Jin Hee, Kim, Woo Jin, Lee, Sang-Do, Park, Joo Hun
• Format: Journal Article
• Language: English
• Published: New Zealand Dove Medical Press Limited 01.01.2018; Dove Medical Press Ltd; Dove Medical Press
• Subjects: Aged; Analysis; Asthma; biomarker; Biomarkers; blood eosinophil; Body Mass Index; Carbon monoxide; Cardiovascular disease; Case-Control Studies; Cement plants; Chronic obstructive lung disease; Chronic obstructive pulmonary disease; Corticosteroid drugs; Councils; Dyspnea; Emphysema; Enrollments; Eosinophils; Exercise Tolerance; Female; Health aspects; Humans; Laboratories; Leukocytes; Lung - physiopathology; Lung diseases; Male; Medical prognosis; Medical research; Middle Aged; Mortality; Normal distribution; Original Research; Physiology; Pneumonia; Prognosis; Pulmonary Disease, Chronic Obstructive - blood; Pulmonary Disease, Chronic Obstructive - diagnosis; Pulmonary Disease, Chronic Obstructive - mortality; Pulmonary Disease, Chronic Obstructive - physiopathology; Pulmonary Emphysema - blood; Pulmonary Emphysema - diagnosis; Pulmonary Emphysema - mortality; Pulmonary Emphysema - physiopathology; Questionnaires; Regression analysis; Republic of Korea; Risk Assessment; Risk Factors; Severity of Illness Index; Spirometry; Steroids; Steroids (Organic compounds); Time Factors; Walk Test; Republic of Korea; United States > US; South Korea; biomarker; COPD; blood eosinophil
• ISSN: 1178-2005; 1176-9106; 1178-2005
• DOI: 10.2147/COPD.S179734

High blood eosinophil count is a predictive biomarker for response to inhaled corticosteroids in prevention of acute exacerbation of COPD, and low blood eosinophil count is associated with pneumonia risk in COPD patients taking inhaled corticosteroids. However, the prognostic role of blood eosinophil count remains underexplored. Therefore, we investigated the associated factors and mortality based on blood eosinophil count in COPD. Patients with COPD were recruited from 16 hospitals of the Korean Obstructive Lung Disease cohort (n=395) and COPD in Dusty Area cohort (n=234) of Kangwon University Hospital. The two merged cohorts were divided based on blood eosinophil count into three groups: high (≥5%), middle (2%-5%), and low (<2%). The high group had longer six-minute walk distance (high =445.8±81.4, middle =428.5±88.0, and low =414.7±86.3 m), higher body mass index (23.3±3.1, 23.1±3.1, and 22.5±3.2 kg/m ), lower emphysema index (18.5±14.1, 22.2±15.3, and 23.7±16.3), and higher inspiratory capacity/total lung capacity ratio (32.6±7.4, 32.4±9.2, and 29.9% ± 8.9%) ( <0.05). The survival period increased with increasing blood eosinophil count (high =9.52±0.23, middle =8.47±1.94, and low =7.42±0.27 years, <0.05). Multivariate linear regression analysis revealed that the emphysema index was independently and negatively correlated with blood eosinophil count ( <0.05). In COPD, the severity of emphysema was independently linked with low blood eosinophil count and the longer survival period was associated with increased blood eosinophil count, though it was not proven in the multivariate analysis.