Identifying prognosis for patients with acute exacerbation of chronic obstructive pulmonary disease (AECOPD) is challenging. Eosinophils and platelet are involved in the development of COPD, which may predict adverse events. 

- The eosinophil to platelet ratio (EPR) < 0.755 before treatment could serve as an early indicator of unfavorable outcomes in acute exacerbation of chronic obstructive pulmonary disease (AECOPD) patients. 
- Researchers found that an EPR below 0.755 significantly correlated with higher mortality rates in AECOPD patients, both overall (25.3% vs. 5.5%) and specifically in emergency room presentations (35.6% vs. 11.1%).

Source: International Journal of COPD | [Read full story](https://www.dovepress.com/a-low-eosinophil-to-platelet-ratio-as-a-worse-prognostic-index-for-eme-peer-reviewed-fulltext-article-COPD)