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Sleep Disorders
Volume 2015, Article ID 734798, 15 pages
Review Article

Nasal Expiratory Positive Airway Pressure Devices (Provent) for OSA: A Systematic Review and Meta-Analysis

1Twin Cities Community Hospital, Templeton, CA 93465, USA
2Department of Otorhinolaryngology, Sleep Medicine Centre, Hospital CUF, 4100-180 Porto, Portugal
3Centre for Research in Health Technologies and Information Systems (CINTESIS), University of Porto, 4200-450 Porto, Portugal
4Clay County Hospital, 911 Stacy Burk Drive, Flora, IL 62839, USA
5Department of Otorhinolaryngology, Hospital Bernardino Rivadavia, Buenos Aires, Argentina
6Department of Head and Neck Surgery, University of California, Los Angeles, CA 90095, USA
7Sleep Medicine Division, Department of Psychiatry and Behavioral Sciences, Stanford Hospital and Clinics, Redwood City, CA 94063, USA
8Division of Otolaryngology, Sleep Surgery, and Sleep Medicine, Tripler Army Medical Center (Tripler AMC), 1 Jarrett White Road, Honolulu, HI 96859, USA

Received 20 September 2015; Revised 18 November 2015; Accepted 19 November 2015

Academic Editor: Giora Pillar

Copyright © 2015 Muhammad Riaz et al. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.


Objective. To quantify the effectiveness of nasal expiratory positive airway pressure (nasal EPAP) devices or Provent as treatment for obstructive sleep apnea (OSA). Methods. PubMed and six other databases were searched through November 15, 2015, without language limitations. Results. Eighteen studies (920 patients) were included. Pre- and post-nasal EPAP means ± standard deviations (M ± SD) for apnea-hypopnea index (AHI) in 345 patients decreased from to events/hr (relative reduction = 53.2%). Random effects modeling mean difference (MD) was −14.78 events/hr [95% CI −19.12, −10.45], value < 0.00001. Oxygen desaturation index (ODI) in 247 patients decreased from to events/hr (relative reduction = 41.5%, value < 0.00001). Lowest oxygen saturation (LSAT) M ± SD improved in 146 patients from % to %, MD 3 oxygen saturation points [95% CI 0.57, 5.63]. Epworth Sleepiness Scale (ESS) M ± SD improved (359 patients) from to , MD −2.5 [95% CI −3.2, −1.8], value < 0.0001. Conclusion. Nasal EPAP (Provent) reduced AHI by 53.2%, ODI by 41.5% and improved LSAT by 3 oxygen saturation points. Generally, there were no clear characteristics (demographic factors, medical history, and/or physical exam finding) that predicted favorable response to these devices. However, limited evidence suggests that high nasal resistance could be associated with treatment failure. Additional studies are needed to identify demographic and polysomnographic characteristics that would predict therapeutic success with nasal EPAP (Provent).