The Prevalence of Asthma-COPD Overlap (ACO) Among Patients with Asthma

Özet

OBJECTIVES: Asthma-chronic obstructive pulmonary disease (COPD) overlap (ACO) is defined as a persistent airflow limitation withfeatures of both asthma and COPD. However, in Turkey, there are limited data about ACO. The aims of the present study were to determine the prevalence of ACO among patients with asthma, to compare the clinical characteristics of patients with ACO and asthma, andto determine the threshold values for the diagnosis of ACO.MATERIALS AND METHODS: The study group comprised 338 patients admitted to the outpatient clinics between 2010 and 2017 andwho had undergone at least three pulmonary function tests within the last 2 years. Patients aged >40 years with a smoking history of >10pack-years or biomass exposure, with at least three features of both diseases, and with reversible and persistent airflow limitation werediagnosed with ACO. The study is a retrospective study so we did not get informed concent.RESULTS: Asthma-chronic obstructive pulmonary disease overlap was diagnosed in 40 (11.8%) patients. Patients with ACO had fewerallergic comorbidities, worse spirometric parameters, and required higher doses of inhaled corticosteroids than patients with asthmaonly (p 0.05). Threshold values were determined as age ≥57.5 years, smoking history ≥14 pack-years, and diagnosis at age ≥40.5 years.CONCLUSION: The frequency of ACO was observed to be very high in patients with asthma. In patients >57.5 years old, with a smokinghistory of >14.5 pack-years, and diagnosed with asthma at >40.5 years old, the probability of ACO diagnosis increases.