A multicenter evaluation of oral pressure therapy for the treatment of obstructive sleep apnea

Abstract

Objective: We aimed to evaluate the impact of a novel noninvasive oral pressure therapy (OPT) (Winx®, ApniCure) system on polysomnographic measures of sleep-disordered breathing, sleep architecture, and sleep stability in obstructive sleep apnea (OSA).

Subjects and methods: A 4-week, multicenter, prospective, open-label, randomized, crossover, first-night order of control vs treatment, single-arm trial was conducted in five American Academy of Sleep Medicine (AASM) - accredited sleep clinics and one research laboratory. Sixty-three subjects (analysis cohort) were studied from a screening cohort of 367 subjects. The analysis cohort was 69.8% men, ages 53.6±8.9 years (mean±SD), body mass index of 32.3±4.5kg/m(2), with mild to severe OSA. At treatment initiation, subjects received random assignment to one night with and one without (control) treatment, and they were assessed again following 28 nights of treatment. Breathing and sleep architecture were assessed each night based on blind scoring by a single centralized scorer using AASM criteria.

Results: Average nightly usage across the take-home period was 6.0±1.4h. There were no severe or serious device-related adverse events (AEs). Median apnea-hypopnea index (AHI) was 27.5 events per hour on the control night, 13.4 events per hour on the first treatment night, and 14.8 events per hour after 28days of treatment. A clinically significant response (treatment AHI ⩽10/h and ⩽50% of control values) was seen in 20 of the 63 subjects evaluated. Rapid eye movement percentage (REM%) was significantly increased, and N1%, stage shifts to N1 sleep, overall stage shifts, total awakenings, and arousals per hour were all significantly reduced at both treatment nights compared to controls. Mean Epworth sleepiness scale (ESS) was significantly reduced from 12.1 to 8.6 (Cohen d effect size, 0.68) in those untreated for two or more weeks prior to OPT study participation and remained unchanged in subjects who directly switched from continuous positive airway pressure (CPAP) therapy to OPT.

Conclusion: Clinically significant improvements in sleep quality and continuity, AHI, ODI, ESS, and overall clinical status were achieved in an easily identified subgroup. OPT was safe and well-tolerated and nightly usage was high.

Keywords: AHI; Compliance; Epworth sleepiness scale; ODI; Obstructive sleep apnea; Oral pressure therapy.

Fig. 1

Oral pressure therapy (OPT) system (WinxTM). The left panel shows the nightstand console unit containing the vacuum pump and saliva reservoir. The right panel shows the mouthpiece. Letter A indicates the vacuum pressure and sensor tubing, B shows the lip seal, and C shows the vacuum aspiration port.

Fig. 2

Shows the flowchart of subject disposition from initial enrolment through to the end of the 28-day take-home portion of the protocol.

Fig. 3

Apnea–hypopnea index at control, first treatment night, and after 28 days of treatment. Points represent individual subjects and lines denote median and interquartile range. *P < .001 vs control by Wilcoxon signed rank test.

Fig. 4

Apnea–hypopnea index (AHI) at control, first treatment night, and after 28 days of treatment in relation to control obstructive sleep apnea severity. Control AHI severity was classified as mild (5–15/h), moderate (15–30/h), or severe (>30/h). Lines denote median and interquartile range. *P < .02 vs control by Wilcoxon signed rank test.

Fig. 5

Relationship between change in apnea–hypopnea index and change in number of sleep-stage shifts between control and first treatment night in the responder cohort.

Fig. 6

Nightly usage (median ± interquartile range) for each subject in the analysis cohort who completed the take-home period.