Asthma-COPD overlap is not a homogeneous disorder: further supporting data.

Asthma-COPD ovelap (ACO) is an umbrella term that encompasses patients with COPD and eosinophilic inflammation (e-COPD) and smoking asthmatics with non-fully reversible airflow obstruction (SA). We compared the clinical characteristics and the inflammatory profile of e-COPD and SA. Patients classified as e-COPD were older and more often male and showed significantly impaired pulmonary function (likely explained by a heavier smoking habit). On the contrary, SA had more atopic features, more reversibility of airflow obstruction and higher IgE levels. The concentrations of IL-5, IL-13, IL-8, IL-6, TNF-α, IL17 in serum were similar between the 2 groups. However, Th2-related biomarkers (periostin, FeNO and blood eosinophils) shower higher median values in e-COPD patients. Our findings reinforce the notion that ACO is a heterogeneous disorder and, as a consequence, it might be unacceptable to offer the same treatment for two related but different conditions.