Comparison of Relationship Between Eosinophil Counts and the Disease Severity in ACO Patients

Background and Aims: There is a new phenotype called asthma COPD overlap (ACO). In bronchial asthma patients with smoking history, the number of patients with ACO was determined. In our previous study, we obtained high percentage of eosinophilia in elderly ACO. Therefore, we analyzed the ratio of eosinophil counts and the disease severity. Methods: In this study, 213 patients (male 116, female 97; age 72 ± 21 years (SD) were extracted in the ACO diagnostic criteria of the Japan Respiratory Society among asthma patients in Erimo town clinic in Hokkaido. We performed a retrospective analysis of eosinophil counts, severity, medication history, smoking history, etc. Results: The severity of ACO was judged as follows. Grade 1: 61, Grade 2: 93, Grade 3: 42, and Grade 4: 17 The number of eosinophils in each grade is shown. Grade 1: 294 ± 183 / μl, Grade 2: 327 ± 167 / μl, Grade 3: 311 ± 241 / μl Grade 4: 308 ± 211 / μl The medication history was ICS single agent 51, ICS + SABA 48, ICS + LABA 57, ICS + leukotriene antagonist (LA) 17, ICS + SABA + LA 14, ICS + LABA + LA 20, others 6. Conclusions: There was a tendency for ACO with eosinophil counts to increase in the elderly, but there was no direct correlation between severity and eosinophils. There are also reports indicating eosinophils decrease due to the effect of smoking. Prospective clinical trials of eosinophil counts are necessary for multifaceted assessment of ACO in future.