D1.507 - Biomarkers of T2-airway inflammation in patients with asthma and COPD overlap

Asthma and COPD are heterogeneous diseases with different phenotypes and endotypes which may coexist in one patient. Use of biologicals in both conditions needs the validation of endotype using biomarkers, such as eosinophil count in blood (Eos), fraction of exhaled nitric oxide (FeNO) and atopy. The aim of this study was to assess the biomarkers of T2-airway inflammation in asthma-COPD overlap in a single secondary center.

We examined 106 outpatients (58% male, aged 38-82 yr, mean age 59 yrs) with asthma and COPD treated with ICS/LABA± LAMA, montelukast. Patients did not receive any biologicals for ≥12 months. The majority of patients (93%) had asthma onset earlier with concomitant COPD developed later (group 1) and in 7% COPD was the first diagnosis with late-onset asthma (group 2). Blood Eos were measured by automatic haemoanalyser. FeNO was assessed by a chemiluminescence analyzer (LR4000; Logan Research, UK). Atopic status was measured by positive serum specific IgE to common inhalant allergens. Presence of allergy, Eos≥150 cell/μl and FeNO≥20 ppb were considered as markers of T2-inflammation.

In both groups patients has similar mean age (59 vs 63 yrs, p>0.05) and males rate (56 vs 86%, p>0.05), asthma severity (moderate/severe 13/87 vs 14/86%, p>0.05) and COPD duration (6 vs 5 yrs, p>0.05). Patients in group 1 had longer duration of asthma (12 vs 1.5 yrs, p<0.01), more concomitant allergic rhinitis (54% vs 14%, p<0.05), higher FEV₁ (50 vs 39% pred, p<0.05) and FEV₁/ FVC rate (56 vs 44%, p<0.05) with less pack-years of smoking (37 vs 51, p<0.05) and LAMA use (58% vs 100%, p<0.05) compared to group 2. All patients had history of smoking and similar rate of former/current smokers (37/61 vs 29/71%, p>0.05), exacerbations during previous year (1.8 vs 1.8, p>0.05) and atopy (53 vs 29% p>0.05) also as rates of uncontrolled asthma ACQ-5≥1.5 (78 vs 80%, p>0.05) and CAT-test≥10 (93 vs 100%, p>0.05) in two groups. In patients with asthma and COPD in groups 1 and 2 blood Eos≥150 cell/μl had 64% and 67% (p>0.05) whereas FeNO≥20 ppb was found in 42% and 0% (p<0.05) respectively. At least one of 3 markers of T2-inflammation was revealed in 77% of patients with early asthma and later COPD and in 71% (p>0.05) of COPD with late-onset asthma

The majority of patients with asthma and concomitant COPD regardless of the order of occurrence have at least one marker (presence of allergy, Eos≥150 cell/μl) of T2-inflammation, except of FeNO≥20 ppb. Increased blood Eos≥150 cell/μl and allergy were the most frequent markers. It seems that many patients with asthma and concomitant COPD may have indications for prescription of biologicals.