Prevalence and features of asthma-COPD overlap in the United States 2007-2012. Clin Respir J 2018 Aug;12(8):2369-2377
Date
06/07/2018Pubmed ID
29873189Pubmed Central ID
PMC6287748DOI
10.1111/crj.12917Scopus ID
2-s2.0-85053046481 (requires institutional sign-in at Scopus site) 36 CitationsAbstract
BACKGROUND: Perceived to be distinct, asthma and chronic obstructive pulmonary disease (COPD) can co-exist and potentially have a worse prognosis than the separate diseases. Yet, little is known about the exact prevalence and the characteristics of the Asthma-COPD overlap (ACO) in the US population.
AIMS: To determine ACO prevalence in the United States, identify ACO predictors, examine ACO association with asthma and COPD severity, and describe distinctive spirometry and laboratory features of ACO.
METHODS: Data on adult participants to the National Health and Nutrition Examination Surveys conducted from 2007 to 2012 was analyzed. ACO was defined as current asthma and post-bronchodilator forced expiratory volume in 1 second/forced vital capacity (FEV1/FVC) <0.7.
RESULTS: Overall, 7,570 participants representing 98.58 million Americans were included in our study. From 2007 to 2012, the crude and age-standardized ACO prevalence were, respectively, 0.96% (95% CI: 0.65%-1.26%) and 1.05% (0.74%-1.37%). In asthma, ACO predictors included older age, male gender, and smoking. In COPD, ACO predictors were non-Hispanic Black race/ethnicity and obesity. ACO was associated with increased ER visits for asthma (OR = 3.46, 95% CI: 1.48-8.06]) and oxygen therapy in COPD (OR = 11.17, 95% CI: 5.17-24.12]). In spirometry, FEV1 and peak expiratory flow were lower in ACO than in asthma or COPD alone.
CONCLUSION: Age-adjusted prevalence of ACO in the United States was 1.05% in 2007-2012, representing 0.94 (95% CI: 0.62-1.26) million Americans. It is much lower than previously reported. The overlap was associated with higher asthma and COPD severity as well as decreased lung function compared with COPD or asthma alone.
Author List
Mendy A, Forno E, Niyonsenga T, Carnahan R, Gasana JAuthor
Janvier Gasana MD, MPH, PhD Adjunct Associate Professor in the Institute for Health and Equity department at Medical College of WisconsinMESH terms used to index this publication - Major topics in bold
AdultAged
Asthma
Cross-Sectional Studies
Female
Forced Expiratory Volume
Humans
Male
Middle Aged
Prevalence
Pulmonary Disease, Chronic Obstructive
Severity of Illness Index
Spirometry
United States
Vital Capacity