Clinical characteristics of physician diagnosed asthma-COPD overlap

Abstract

Purpose: Few studies evaluated in-depth characterization of physician-diagnosed asthma-COPD overlap (ACO), and its clinical differences with asthma or COPD.

Methods: A cross sectional study of 417 patients in Hanyang Obstructive Pulmonary diseases Evaluation (HOPE) cohort was performed to compare the clinical characteristics of physician diagnosed ACO, asthma, and COPD.

Results: Of the 417 patients, 170(40.8%), 171(41.0%), and 76(18.2%) were diagnosed of asthma, COPD, and ACO, respectively. Compared to patients with other diseases, those with asthma were younger, had lowest prevalence of male, current-smoker, biomass exposure, previous pulmonary tuberculosis, and hypertension, and had highest prevalence of allergic rhinitis, atopic dermatitis, and gastroesophageal reflux. In comparison, COPD patients had lowest body mass index and highest prevalence of previous pulmonary tuberculosis, previous pneumonia, bronchiectasis, and hypertension. ACO patients had highest prevalence of current-smoker. Regarding pulmonary function, FEV₁ was highest in patients with asthma, followed by those with ACO, and those with COPD. The proportion of patients with mMRC scores ≥ 2 was most frequent in COPD patients and lowest in asthma patients. While the porportion of patients with positive bronchodilator response was highest in ACO patients, the porportion of positive bronchoprovocation test was highest in asthma patients. Peripheral eosinophil counts and exhaled nitro oxide levels were highest in asthma patients and lowest in COPD patients.

Conclusions: Physician-diagnosed ACO patients had highest prevalence of current-smoker and their symptoms, lung function, and eosinophil counts were between the two conditions.