A comparison of diagnostic consistency for asthma-chronic obstructive pulmonary disease overlap and clinical characteristics study

Background The diagnostic criteria for asthma-chronic obstructive pulmonary disease overlap have not been unified. Different studies have used different criteria, and this has led to diagnostic inconsistencies. Methods We collected data of patients who were older than 40 years and hospitalised because of chronic bronchial diseases. One hundred and seventy-one patients were included in this study. We compared seven different diagnostic criteria, examined their consistency, and analysed differences among groups classified with each set. Results The prevalence of ACO ranged between 7.02 and 27.49% depending on the criteria applied. The patients who met the Soler-Cataluna et al. criteria also met the GesEPOC criteria. Rhee has proposed the strictest diagnostic criteria; hence, the number of patients who met these criteria was the smallest, and those patients also met the diagnostic criteria proposed by the other studies. We found that applying the different sets of criteria did not lead to the selection of the same population, while there were no statistical differences in age, disease duration, allergens, and inflammatory markers. Conclusions The diagnostic criteria of ACO have not been unified, which hinders the design and progress of clinical studies that would investigate the ACO phenotypes and underlying mechanisms.