The Effect of Intermittent Negative Air Pressure, iNAPandreg; on Subjective Daytime Sleepiness in Middle-aged Patients with Moderate Obstructive Sleep Apnea

Background: In a previous study, we have demonstrated that intermittent negative air pressure (iNAP®) therapy improves the apnea severity in patients with mild-to-moderate obstructive sleep apnea syndrome (OSAS). Purpose: This study was conducted to evaluate the effect of subjective daytime sleepiness for patients with moderate OSA. Methods and Materials: A total of seven men and one woman with moderate OSA were enrolled in this singlecenter, prospective, non-randomized clinical study. All patients used the iNAP® devices in their home during sleep between the diagnostic and second polysomnography assessment. To determine the changes in the subjective sleepiness between the diagnostic and iNAP®-treated PSGs, the Epworth Sleepiness Scale (ESS) score was estimated immediately before the first and second PSG. Results: At baseline the mean (standard deviation) age and body mass index of the study participants were 41.5 (± 6.3) years and 23.2 (± 2.6), respectively. The baseline apnea-hypopnea index (AHI) was 22.2 ± 2.2, and decreased to 15.6 ± 5.3 after the iNAP® therapy (p=0.007). The arousal index improved from 29.8 ± 9.2 at baseline to 19.3 ± 5.1 with the iNAP® device (p=0.0025). With the improvement of apnea severity, the ESS decreased from 14.0 ± 3.8 to 9.1 ± 4.4 (p=0.0076). Conclusions: The negative pressure therapy with the iNAP® Sleep Therapy System ameliorated both the apnea severity and the subjective daytime sleepiness in middle-aged patients with moderate OSA.