Asthma and Impaired Sleep: Identifying Treatable Traits in the SCAPIS Study

Introduction: This study compared sleep quality and insomnia symptoms in individuals with and without asthma and identified potentially treatable traits that could be used to improve sleep in asthma. Methods: This cross-sectional analysis included 28,828 participants (aged 50– 64). Post-bronchodilator forced expiratory volume (FEV 1 ) and forced vital capacity (FVC) were measured. Questionnaires assessed physician-diagnosed asthma, asthma-related symptoms, exacerbations, allergic rhinitis, chronic rhinosinusitis (CRS), nocturnal breathing disorders and reflux (snoring, sleep apnea, nocturnal gastroesophageal reflux [nGER]), and sleep quality. Insomnia symptoms included difficulties initiating sleep (DIS), difficulties maintaining sleep (DMS), and early morning awakening (EMA). Results: Current asthma was associated with impaired sleep quality (OR=1.56; [95% CI:] 1.39– 1.75), DIS (1.59; [1.40– 1.81]), DMS (1.36; [1.22– 1.51]), EMA (1.31; [1.16– 1.48]), and any insomnia symptom (1.38; [1.25– 1.52]). Among individuals with asthma, allergic rhinitis was linked to impaired sleep quality (1.28; [1.01– 1.62]), while CRS, asthma symptoms, exacerbations, snoring, sleep apnea and nGER were associated with impaired sleep quality and insomnia symptoms. Those with uncontrolled asthma, CRS, or nocturnal breathing disorders and reflux had higher odds of impaired sleep quality and any insomnia symptom, with the strongest associations in those with all three conditions (5.68; [3.47– 9.29] and 3.63; [2.26– 5.85], respectively). Conclusion: Asthma is associated with impaired sleep quality and insomnia symptoms in middle-aged adults. Our study also indicates that in asthma, impaired sleep quality and insomnia symptoms are linked to three potentially treatable traits, namely lack of asthma control, upper airway disorders, and nocturnal breathing disorders and reflux.