Researchers in Hangzhou, China, have determined that lower eosinophil counts in patients with acute exacerbation of COPD (AECOPD) are associated with increased in-hospital mortality.
Results of the study, “Nonlinear Association Between Blood Eosinophil Counts and Clinical Outcomes in ICU-Admitted Patients With Acute Exacerbation of COPD: A Retrospective Observational Study,” were published in BMC Pulmonary Medicine.
The researchers used data collected from the Medical Information Mart for Intensive Care (MIMIC) IV 2.2 database, a repository of deidentified electronic health records from patients at Beth Israel Deaconess Medical Center. The data is available to credentialed researchers around the world.
For this study, 1,855 COPD patients with blood eosinophil counts measured within the first 24 hours following admission to the ICU were included. They compared in-hospital mortality across eosinophil thresholds for patients categorized into different eosinophil groups, adjusted for confounders with four Cox regression models. These groups were:
- Group 1 – eosinophil counts less than 0.1 x 109
- Group 2 – eosinophil counts between 0.1 x 109 and 0.3 x 109
- Group 3 – eosinophil counts greater than or equal to 0.3 x 109
Compared with group 1, group 2 “exhibited a significantly lower risk of in-hospital mortality,” the researchers wrote. Meanwhile, group 3 showed a mortality reduction only in the unadjusted model. Once adjustments were made, however, this group lost any statistical significance.
The researchers concluded that lower eosinophil counts were associated with increased in-hospital mortality among critically ill AECOPD patients.
“Absolute eosinophil counts may serve as a prognostic biomarker to support personalized ICU management,” they wrote. However, they added that additional prospective studies are needed to validate the findings of this study and to inform clinical decision-making.
