Since ACO (Asthma-COPD-Overlap) does not equate to asthma or COPD (Chronic Obstructive Pulmonary Disease) criteria, such patients are poorly evaluated.

A new study published in Respiratory Medicine Case Reports aimed to screen asthma and COPD for an alternative diagnosis of ACO, and thereafter, to determine subgroups of patients.

Using GINA-GOLD stepwise approach, asthmatics and COPD were screened for ACO. Cluster analysis was then performed employing Multiple Correspondent Analysis (MCA) model, encompassing 9 variables – age, symptoms onset, sex, BMI (Body Mass Index), smoking, FEV-1, dyspnea, exacerbation, comorbidity. Finally, clusters were compared to determine phenotypes.

Overall, 172 ACO subjects underwent MCA analysis, which was then focused on 55 subjects, having at least one cosine squared > 0.3. Six clusters were identified, allowing the description of 4 phenotypes. It was found that phenotype A represented overweight heavy smokers, with an early onset and a severe disease—27% of ACO patients. Phenotype B gathered similar patients, with a late onset—29%. Patients from Phenotypes C-D were slighter smokers—presenting a moderate disease—with early and late onsets, respectively.

Hence, the results confirmed the heterogeneity of clusters, allowing for the identification of 4 phenotypes. It was stated that further prospective studies are essential to establish these data and to determine specific management requirements and prognostic value.