Nasal Dilator Strip is an Effective Placebo Intervention for Severe Obstructive Sleep Apnea

Study Objectives: The aim of this study was to evaluate the effects of nasal dilator strip (NDS) as a placebo intervention compared with continuous positive airway pressure (CPAP) treatment in patients with severe obstructive sleep apnea (OSA). Methods: Patients were treated with both NDS and nasal CPAP. The sequence was randomized and interposed by 15 days of washout. Polysomnography was performed at baseline and on the first night of intervention with NDS and CPAP (titration). The Epworth Sleepiness Scale (ESS), Functional Outcomes of Sleep Questionnaire (FOSQ), and Beck Depression Inventory (BDI) were completed at baseline and at the end of both interventions. A questionnaire on the comfort and satisfaction (0 = no to 10 = total) was completed at the end of each intervention. Results: Twenty-six patients with OSA were evaluated (19 male; age 46.3 +/- 9.3 y; body mass index 33.2 +/- 5.1 kg/m(2); ESS 15.8 +/- 4.1; apnea-hypopnea index 60.7 +/- 25.2). Adherence was high in both NDS (98%) and CPAP interventions (94%; 5.8 +/- 1.7 h/night). In contrast to the baseline values, NDS intervention had no significant effect on all polysomnographic parameters, but NDS improved somnolence (ESS 13.0 +/- 5.4, p = 0.001) and depressive symptoms (BDI 7.7 +/- 6.9, p = 0.005). Reported satisfaction was significantly higher for CPAP than for NDS (sleep quality 9.2 +/- 0.8 vs. 6.1 +/- 2.1; wake up at morning: 8.6 +/- 1.2 vs. 6.0 +/- 2.2; daily activities: 8.9 +/- 1.4 vs. 5.8 +/- 1.5; quality of life: 8.3 +/- 2.1 vs. 3.8 +/- 3.5, p < 0.001), but similar low levels of difficulty for both interventions were observed (1.3 +/- 2.2 vs. 0.3 +/- 1.3, p = 0.098). Conclusions: Our data indicate that NDS is an attractive placebo intervention for randomized controlled trials evaluating the effects of CPAP in sleepy patients with OSA.