Individuals suffering from asthma and chronic obstructive pulmonary disease (COPD) overlap (ACO) have a high prevalence of insomnia and respiratory symptoms according to the results of a study published in PLoS One.
ACO is characterized by persistent airflow limitation with several features usually associated with asthma and several usually associated with COPD. Compared with individuals who have only asthma or only COPD, individuals with ACO have frequent exacerbations and poor quality of life and use a disproportionate amount of healthcare resources.
A team of Swedish researchers identified individuals aged 40 years or older with ACO from 2 Northern European population surveys: Respiratory Health In Northern Europe (RHINE) and the Global Allergy and Asthma Network in Europe (GA2LEN).
Both surveys included questions about asthma, COPD, and respiratory and sleep-related symptoms, including difficulty falling asleep, difficulty maintaining sleep, early-morning awakening, and excessive daytime sleepiness. The investigators defined ACO as having both self-reported asthma and COPD.
The investigators found ACO in 1% of the 25,429 participants from the population surveys. In individuals with ACO, there was a higher prevalence of both insomnia and respiratory symptoms compared with those who had only asthma or only COPD. People with ACO had 2 to 3 times the risk of having sleep-related symptoms, including difficulty falling asleep, difficulty maintaining sleep, early-morning awakening, and excessive daytime sleepiness compared with those without asthma or COPD, after adjusting for age, sex, body mass index, smoking history, and educational level (odds ratio, 2.14).
The authors noted that ACO was more common in women and that those with ACO and COPD had a higher body mass index than participants with asthma or healthy controls. Individuals with ACO and COPD also had a higher prevalence of smoking and a lower prevalence of university-level education than either patients with asthma or healthy control patients. The study was limited by the reliability of self-reported diagnoses. Furthermore, pulmonary function data were available only in a subsample of the population. The authors called for therapeutic studies to identify optimal treatment for patients with ACO.
Mindus S, Malinovschi A, Ekerljung L, et al. Asthma and COPD overlap (ACO) is related to a high burden of sleep disturbance and respiratory symptoms: results from the RHINE and Swedish GA2LEN surveys [published online April 2, 2018]. PLoS One. doi:10.1371/journal.pone.0195055