Abstract Rationale Chronic Obstructive Pulmonary Disease (COPD) is a chronic respiratory disorder with marked heterogeneity and complexity, creating challenges to clinical assessments and risk stratification in terms of predicting mortality in acute exacerbations. Recently, the exploration of biomarkers has opened new avenues for the precise evaluation. One such biomarker is the eosinophil-to-platelet ratio (EPR), which can be derived from routine complete blood count for patients presenting with acute exacerbations of COPD (AECOPD) and integrates inflammation and thrombotic pathways, but its prognostic accuracy for mortality is unknown. Methods MEDLINE and Embase were searched (inception to October 2025) for studies evaluating EPR 0.755 as a predictor of mortality in AECOPD. Two reviewers independently screened records and extracted 2 × 2 data. Diagnostic accuracy was pooled using a Bayesian model in MetaBayesDTA. Risk of bias was assessed with QUADAS-2 and visualized with ROBVIS. Results Three prospective cohort studies (n = 590) were included: Gandhi et al. (n = 205), Hu et al. (n = 205, ERP ), and Yogesh et al. (n = 180). Pooled sensitivity was 65.6% (46.3-77.7%) and specificity was 74.6% (45.4-89.0%). Positive likelihood ratio was 2.57 (1.7-3.9); negative likelihood ratio 0.46 (0.36-0.59). The area under the SROC curve was 0.76 (0.68-0.84). QUADAS-2 assessment showed low risk of bias in patient selection, reference standard, and flow/timing, but some concerns in the index test domain across all studies due to non-pre-specified or post-hoc application of the EPR 0.755 cutoff. Conclusion EPR 0.755 demonstrates good accuracy for predicting AECOPD mortality, comparable to validated scores, using real-time, low-cost data. Despite limited evidence (3 studies), its simplicity makes it a promising triage adjunct. Future studies should use larger cohorts, evaluate serial EPR, and explore its incorporation into clinical scores to improve bedside risk stratification. This abstract is funded by: None
Asghar et al. (Fri,) studied this question.