Effect of nasal-valve dilation on obstructive sleep apnea

Objective: Nasal-valve dilation reduces nasal resistance and increases air flow, It is possible that this mechanism prevents hypopharyngeal collapse a nd sleep apneas. We investigated the effect of a plastic device (Nozovent; Prevancure AB; Vastra FroIunda, Sweden)-which dilates the nasal valve-on pa tients with obstructive sleep apnea (OSA). Design: Prospective interventional study. Subjects: Twenty-six consecutive patients with OSA were included (22 men; m ean +/- SD age, 54.8 +/- 11.3 years; respiratory disturbance index [RDI], 3 4.4 +/- 18.5 events/h; body mass index, 31.6 +/- 5.7 kg/m(2)). Intervention: The nasal dilator was inserted during sleep into the nares an d fitted to exert a dilating force on the nasal valves by means of its elas ticity. Measurements: Polysomnographic studies were performed before and after 1 mo nth of treatment, A responder is defined as one with a reduction in RDI to < 50% of the baseline value and RDI of less than or equal to 10 events/h du ring treatment. Results: Five patients dropped out. As a result, only 21 patients were anal yzed. Four patients responded, and 17 patients were nonresponders. In the w hole population, neither the mean values for respiration during sleep nor s leep staging changed significantly with the device. Conclusions: The investigated nasal dilator had no effect on sleep-related breathing disorders in patients with model ate to severe OSA. The reduction in nasal resistance does not prevent hypopharyngeal obstruction.