Nasal obstruction – impact on insomnia symptoms and sleep-disordered breathing

Abstract: Background: Nasal obstruction is very common in the general population, but the role of nasal obstruction in sleep quality is not clear. Nasal obstruction is also prevalent in patients with obstructive sleep apnoea (OSA) and may contribute to poor adherence to continuous positive airway pressure (CPAP) treatment.Aims: To investigate the impact of subjective nasal obstruction, as a single symptom or as part of chronic rhinosinusitis (CRS), in both objective and subjective sleep quality, in three different population based cohorts. Another aim was to investigate the usefulness of the Sinonasal Outcome Test-22 (SNOT-22) and peak nasal inspiratory flow (PNIF) in the treatment of OSA patients.Methods and results: In paper I (the SHE-study), a community-based sample of 400 women were investigated with polysomnography and questions on sleep quality, daytime- and nasal symptoms. Women with nasal obstruction at night (n=30) had significantly higher prevalence of several night time symptoms and excessive daytime sleepiness (EDS), but the polysomnography was normal.In paper II (the GA2LEN study, n= 26, 647) and paper III (RHINE II and RHINE III studies, n= 5, 145) questionnaires on sleep quality, daytime- and nasal symptoms were used, and CRS was defined according to the epidemiological diagnostic criteria of the European Position Paper of Rhinosinusitis and Nasal Polyps (EPOS). In paper II, sleep problems were highly prevalent in CRS, and there was a dose-response relationship between the disease severity of CRS and sleep problems. The addition of persistent allergic rhinitis to CRS further increased the risk of sleep problems.In paper III, 2.7% of individuals without nasal symptoms at baseline had developed CRS at follow-up 10 years later. Strong associations between incident CRS and impaired sleep quality and EDS were found. Three insomnia symptoms at baseline increased the risk for CRS at follow-up.In paper IV, 197 OSA patients initiating CPAP treatment were investigated before starting CPAP and at the follow-up 3-4 weeks later. SNOT-22 scores were generally high among all OSA patients indicating a large sinonasal disease burden, and improved among those with CPAP adherence ≥ 4 hours/night. A low PNIF value increased the risk for poor CPAP adherence.Conclusions: Subjective nasal obstruction at night impairs subjective sleep quality in women, but does not affect objective sleep quality. CRS impairs subjective sleep quality, and insomnia symptoms may be a risk factor for CRS. SNOT-22 and PNIF may be useful tools in the treatment of OSA patients.