Comparison of epidemiological characteristics and medical utilization of asthma-predominant ACO(Asthma COPD Overlap) and COPD

RATIONALE: Asthma-COPD overlap (ACO) is a disorder in which features of asthma and COPD are mixed, and the definition, characteristics and the socio-economic burden of the disease are still controversial. Thus we sought to compare the epidemiological characteristics and medical utilization of asthma-predominant ACO (A-ACO) and COPD.

METHODS: In the Korean National Health and Nutrition Examination Survey (KNHANES) conducted between 2007 -2012, subjects who have FEV₁/FVC < 0.7, FEV1 ≥ 50% over 40 years were included. Wheezing was indicated as presence (W+) or absence (W-), and smoking history was defined as S+ if subject was a smoker ≥10 pack-years and S- if subject was a never or ex-smoker <10 pack-years. The subjects were divided into 4 groups of W-S-, W-S+, W+S-, W+S+. W+S- and W+S+ were regarded as an A-ACO and COPD, respectively. KNHANES and linked National Health Insurance data was analyzed.

RESULTS: Subjects aged 50 to 70s were more frequent in W+S+ group. Socioeconomic status (SES) was the lowest in the W+S-group. Regarding the health-related quality of life (QOL), it was the poorest in the W+S- group. Almost fundamental nutrients intake were decreased in the W+S- group. Otherwise, costs and number of outpatient visits and total medical used days were the highest in the W+S+ group.

CONCLUSIONS: A-ACO group seems to suffer from poorer SES, malnutrition, and lower QOL than COPD groups. In addition, access to medical care is also lower than that of COPD patients. It seems that A-ACOS patients need more social and medical support and attention of government.