Review on the correlation between chronic obstructive pulmonary disease and eosinophil in peripheral blood

Chronic obstructive pulmonary disease (COPD) is an irreversible disease characterized by the limitation of continuous airflow. Eosinophil (EOS) in peripheral blood plays a key role in the acute exacerbation of COPD. Eosinophil-increased COPD has become an important variant of COPD and the focus of individualized treatment of COPD. Numerous studies have shown that an increased eosinophil count or an increased percentage in the peripheral blood closely correlates to the acute exacerbation and prognosis of COPD. Therefore, this study intends to review the progress of domestic and foreign research on the correlation between COPD and EOS.