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Asthma-COPD Overlap in Low Income Countries

J Allergy Clin Immunol; ePub 2018 Oct 3; Morgan, et al

Asthma-COPD overlap (ACO) may be as prevalent and more severe in low- and middle-income countries (LMICs) than has been reported in high-income settings, a new study suggests. Researchers compiled cross-sectional data for 11,923 participants aged 35-92 years from 4 population-based studies in 12 settings. COPD was defined as post-bronchodilator FEV1/FVC below the lower limit of normal, asthma as wheeze or medication use in 12 months or self-reported physician diagnosis, and ACO has having both. Among the findings:

  • The prevalence of ACO was 3.8%.
  • The odds of having ACO were greater with household exposure to biomass fuel smoke (OR=1.48), smoking (OR=1.28), and having primary or less education (OR=1.35), when compared to non-obstructed individuals.
  • ACO was associated with severe breathing obstruction and severe spirometric deficits vs those with asthma or COPD alone.


Morgan BW, Grigsby MR, Siddharthan T, et al. Epidemiology and risk factors of asthma-COPD in low- and middle-income countries. [Published online ahead of print October 3, 2018]. J Allergy Clin Immunol. doi:10.1016/j.jaci.2018.06.052.