Wednesday, 14 October 2015
Hall D1 Foyer (Floor 3) (Coex Convention Center)
Ha Kyeong Won, MD
,
Division of Allergy and Clinical Immunology, Department of Internal Medicine, Seoul National University Hospital, Seoul, South Korea
Kyoung Hee Sohn, MD
,
Department of Internal Medicine, Seoul National University College of Medicine, Seoul, South Korea
Byung-Keun Kim, MD
,
Seoul National University Bundang Hospital, Seoul, South Korea
Ju-Young Kim, MD
,
Regional Pharmacovigilance Center, Seoul National University Hospital, Seoul, South Korea
Eun-Jung Jo, MD
,
Pusan National University Hospital, Busan, South Korea
Kyung-Mook Kim, MD
,
Department of Internal Medicine, Pogunhan Mom Hospital, Seoul, South Korea
Heung Woo Park, MD, PhD
,
Internal Medicine, Seoul National University College of Medicine, Seoul, South Korea
Yoon-Seok Chang, MD, PhD
,
Internal Medicine, Seoul National University College of Medicine, Seoul, South Korea
Sang-Heon Cho, MD, PhD
,
Institute of Allergy and Clinical Immunology, Seoul National University Medical Research Center, Seoul, South Korea
Woo-Jung Song, MD
,
Internal Medicine, Seoul National University College of Medicine, Seoul, South Korea
Background: Sputum eosinophilia is a useful biomarker for corticosteroid response in patients with asthma or chronic cough. However, sputum induction requires specialized personnel and facilities and is not always feasible. Recent evidence suggests a moderate degree of diagnostic utility of less invasive biomarkers, such as blood eosinophils, in predicting sputum eosinophilia in asthma. However, none in the literature has examined the diagnostic utility of blood eosinophils for sputum eosinophilia in patients with non-asthmatic chronic cough.
Methods: We examined the datasets of elderly asthma and non-asthmatic chronic cough recruited from previously established cohorts. The inclusion criteria were as follows: 1) elderly subjects (≥65 years old), 2) no current oral or inhaled corticosteroids and 3) no significant comorbidities. Sputum eosinophilia was defined as induced sputum eosinophils≥3%. The diagnostic utility was assessed using receiver operating curve (ROC) analyses for blood eosinophils in predicting sputum eosinophilia.
Results: A total of 74 elderly asthma and 75 non-asthmatic chronic cough patients were analyzed. There were no significant difference in their demographic profiles (age, gender and smoking) between two groups. Of them, 59 elderly asthma and 45 non-asthmatic chronic cough patients had sputum eosinophilia. In Spearman tests, the correlations between blood eosinophils% and sputum eosinophil% were significant in eosinophilic asthma (r=0.577, p<0.001) but not in non-asthmatic eosinophilic bronchitis (r=0.019, p=0.870). In ROC analyses for sputum eosinophilia, blood eosinophils showed a moderate utility (the area under the ROC curve [AUC] 0.838) in asthma, but no utility (AUC 0.489) in non-asthmatic chronic cough.
Conclusions: Unlike asthma, blood eosinophils did not have any diagnostic utility for sputum eosinophilia in non-asthmatic chronic cough. These findings could suggest a different pathophysiology in airway eosinophilic inflammation between two entities.
