Eosinophil count can predict dyspnea level in patients with acute exacerbation of chronic obstructive pulmonary disease

Blood eosinophil count is associated with measurements have been used as biomarkers for eosinophil-related airway inflammation. Eosinophils are found in the airways, tissues, and blood during stable disease or acute exacerbations of COPD (AECOPD). The modified Medical Research Council dyspnea scale (mMRC) and COPD assessment test (CAT) scores have been shown to be useful as novel tools for evaluating these aspects of COPD.
The aim. This study aimed to investigate the relation of blood eosinophil count with the assessment scales and the number of emergency department (ED) admissions in patients with acute exacerbations COPD. 
Study Design. Cross-Sectional Study. Methods. Based on eosinophil count, the patients were divided into two groups: < 300 cells μL−1 and ≥ 300 cells μL−1. For these two groups, the relationship between acute exacerbation and the number of admissions to ED, the number of hospitalizations in the last one year, CAT score, mMRC score, and comorbid diseases were analyzed. 
Results. 166 patients was mean age 69.0, 126 (75.9%) male. Patients with high eosinophil count had fewer ED admission compared with those with low eosinophil count(5 and 10, respectively), Median mMRC score of patients with low eosinophil count was significantly higher compared with that of patients with high eosinophil count(p = 0.022).The difference between the median CAT scores of the two groups was not statistically significant. A statistically significant, negative relationship was found between the eosinophil count and mMRC scores (r = −0.219; p = 0.005). 
Conclusion. High levels of eosinophilia in patients presenting with AECOPD are associated with low mMRC score. Also, although not statistically significant, the number of admissions to the ED may be lower.

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