The concept of asthma and COPD as separate conditions has been questioned, and the term asthma–COPD overlap syndrome has been introduced. We assessed the prevalence, symptoms, and lifestyle factors of asthma–COPD overlap (ACO) in a large Norwegian population-based study.
From 2006 to 2008, a total of 50,777 residents of Nord-Trøndelag participated in the Nord-Trøndelag Health Study, Norway. They completed questionnaires regarding respiratory symptoms, disease status, and medication use. We estimated the prevalence and 95% confidence intervals of ACO. Additionally, spirometry was used to estimate the prevalence of ACO in a subgroup.
The prevalence of self-reported ACO was 1.9%, and in age groups <40, 40–60 and ≥60 years it was 0.7%, 1.4%, and 3.2%, respectively. Among those reporting COPD, the proportion of ACO was 0.56. In the spirometry subgroup when ACO was defined as doctor diagnosed asthma ever and FEV1/FVC < 0.70, the prevalence of ACO was 2.0%. All respiratory symptoms, separately or in combination, as well as medication use were reported most frequently in those with ACO compared to the other groups. Strikingly, we observed a two-fold higher proportion of allergic rhinitis in ACO compared to COPD only.
In this Norwegian population, the prevalence of self-reported ACO was 1.9%, and the corresponding proportion of ACO among those with COPD was 0.56. Participants with ACO generally had the highest proportions of respiratory symptoms compared to asthma or COPD. 相似文献