Insomnia symptoms and asthma control-Interrelations and importance of comorbidities

Background Insomnia symptoms are common with asthma. The aim of the study was to analyse the associations between insomnia symptoms and asthma control, asthma severity, and asthma-related comorbidity in a community-based population. Methods Adults (n = 23 875, ages 18-45) from the community-based LifeGene study answered a questionnaire on insomnia symptoms, airway symptoms, asthma diagnosis, asthma medication, and asthma-related comorbidities (chronic rhinosinusitis, gastro-oesophageal reflux, anxiety, depression, or obesity). Results Of the participants, 1272 (5.3%) had asthma. The prevalence of any insomnia symptom was higher in participants with uncontrolled asthma (n = 201) than with controlled or partially controlled asthma (32.2% vs 19.9% and 20.1%, respectively, P < .01). There was no significant difference in the prevalence of insomnia symptoms between subjects with controlled asthma and subjects without asthma. Subjects with asthma and any asthma-related comorbidity reported more insomnia symptoms (29.0% vs 22.4%, P < .01) compared to asthmatics without comorbidity. Moreover, the prevalence was highest among subjects reporting both uncontrolled asthma and any asthma-related comorbidity (45.1%, P < .01). Uncontrolled asthma remained significantly associated with insomnia symptoms (OR 1.72 (1.15-2.56)) after adjusting for age, sex, BMI, smoking history, comorbidities, physical activity, and educational level, while medication level was not. Among asthma-related comorbidities, chronic rhinosinusitis (OR 1.62 (1.20-2.19)), obesity (1.87 (1.07-3.25)), and depression (OR 1.85 (1.34-2.55)) were independently associated with insomnia symptoms. Conclusion Uncontrolled asthma was significantly associated with insomnia symptoms, while controlled or partially controlled asthma was not. Asthma-related comorbidity is of great importance, and asthma control seems to be more important than asthma severity for insomnia symptoms.