0558 The Spectrum of Sleep Disturbances in Difficult-to-Treat Asthma: Predominance of Sleep-Disordered Breathing

Abstract Introduction Sleep problems are common in individuals with asthma, and several nocturnal symptoms overlap with asthma-related manifestations. Evidence indicates that sleep disorders may contribute to poor asthma control or signal suboptimal disease management. This study aimed to determine the prevalence and spectrum of sleep disorders in patients with difficult-to-treat asthma and to identify sleep-related factors associated with poor disease control. Methods This prospective single-centre study was conducted at the University Clinic Golnik. Consecutive patients with difficult-to-treat asthma were recruited from a multidisciplinary outpatient clinic between August 2022 and February 2024. Polysomnography was performed during clinical stability, and medical records were reviewed. Results A total of 142 patients were enrolled (53% male, mean age 58.5 ± 12.6 years). Sleep disturbances were highly prevalent across multiple domains. Patients reported snoring (33%), breathing pauses (27%), night awakenings (60%), night cough (42%), nocturia (67%), restless leg syndrome symptoms (41%), restless sleep (34%), unrefreshed sleep (34%), and morning headaches (18%). Polysomnography showed prolonged sleep latency in 68%, prolonged wake after sleep onset in 86%, suboptimal sleep efficiency in 78%, an arousal index >15/h in 53%, and a periodic leg movement index >15/h in 44%. Sleep-disordered breathing (SDB) was diagnosed in 70.4 % of patients according to ICSD-3-TR criteria. In univariate logistic regression, poor asthma control (Asthma Control Test < 20) was associated with SDB (OR 2.71, 95% CI 1.28–5.70), breathing pauses (OR 3.84, 95% CI 1.69–8.74), night awakenings (OR 2.85, 95% CI 1.40–5.79), restless sleep (OR 4.11, 95% CI 1.91–8.82), and unrefreshed sleep (OR 3.34, 95% CI 1.55–7.17). In multivariate logistic regression adjusting for these sleep disturbances as well as age, obesity, gastroesophageal reflux disease, smoking status, allergic rhinitis, and cardiovascular disorders, both SDB (OR 3.17, 95% CI 1.27-7.90) and unrefreshed sleep (OR 2.51, 95% CI 1.02-6.19) remained independently associated with poor asthma control. Conclusion Sleep disturbances were highly prevalent in patients with difficult-to-treat asthma, with more than 70% diagnosed with sleep-disordered breathing. While multiple nocturnal symptoms were associated with poor asthma control in univariate analysis, only sleep-disordered breathing and unrefreshed sleep emerged as independent predictors. Support (if any)