High Blood Eosinophil Count Linked to Asthma-Related Hospital Readmission

Eosinophil Granulocytes COPD
Eosinophil Granulocytes COPD
A high blood eosinophil count may increase the risk for a second asthma-related hospitalization within 1 year following an initial hospitalization.

A high blood eosinophil count increased the risk for a second asthma-related hospitalization within 1 year, according to a study published in PloS One

Researchers examined records for patients who were hospitalized for asthma-related complications and had a blood eosinophil count taken the year prior to the hospitalization. These patients were then monitored for another asthma-related hospitalization the following year. A high blood eosinophil count was defined as ≥0.35×109 cells/L.

Of the 2613 patients included, 32% had high blood eosinophil counts the year prior to their asthma-related hospitalizations, and they were more likely to have rhinitis, atopic eczema, nasal polyps, or to have never smoked. When blood evaluations were completed within 4 weeks of the initial hospitalization, patients were 38% more likely to have a higher blood eosinophil count (P =.014). In the 4 weeks after initial hospitalization, 6 patients were readmitted to the hospital, but these readmissions were not associated with high blood eosinophil counts.

In the year after initial hospitalization, 130 of the 2613 patients were readmitted, and the patients with high blood eosinophil counts had a 49% chance of being readmitted (95% CI, 1.04-2.13; P =.029). Patients with high blood eosinophil counts who were nonsmokers had a greater chance of readmission (hazard ratio, 1.84; 95% CI, 1.20-2.80; P =.005), but this likelihood was not as strong in current smokers.

Future studies need to examine the relationship between prescribed medications after initial hospitalization and before readmission, reanalyze the relationship between readmission and smoking, and increase study size to increase statistical power. 

The researchers concluded that patients with a high blood eosinophil count were more likely to be readmitted to the hospital the year following an initial asthma-related hospitalization.

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Disclosures: This study was supported by AstraZeneca. Please refer to reference for a complete list of authors’ disclosures


Kerhof M, Tram TN, van den Berge M, et al. Association between blood eosinophil count and risk of readmission for patients with asthma: historical cohort study. PLoS One. 2018;13(7):e0201143. doi:10.1371/journal.pone.0201143