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Original research
Comparing treatment effects of a convenient vibratory positional device to CPAP in positional OSA: a crossover randomised controlled trial
  1. Yingjuan Mok1,2,
  2. Alvin Tan1,3,
  3. Pon Poh Hsu1,3,
  4. Audrey Seow4,
  5. Yiong Huak Chan5,
  6. Hang Siang Wong1,2,
  7. Yvonne Poh4,
  8. Keith K H Wong6
  1. 1 Department of Sleep Medicine, Surgery and Science, Changi General Hospital, Singapore, Singapore
  2. 2 Department of Respiratory and Critical Care Medicine, Changi General Hospital, Singapore, Singapore
  3. 3 Department of Otolaryngology, Head & Neck Surgery, Changi General Hospital, Singapore, Singapore
  4. 4 Allied Health Division, Changi General Hospital, Singapore, Singapore
  5. 5 Biostatistics Unit, Yong Loo Lin School of Medicine, National University Singapore, Singapore, Singapore
  6. 6 Department of Respiratory & Sleep Medicine, Royal Prince Alfred Hospital, Sydney, New South Wales, Australia
  1. Correspondence to Dr Yingjuan Mok, Changi General Hospital, Singapore 529889, Singapore; mok.yingjuan{at}


Objectives Up to 77% of patients with obstructive sleep apnoea (OSA) have positional OSA (POSA) but traditional positional therapy (PT) methods have failed as they were poorly tolerated. New convenient vibratory PT devices have been invented but while recent studies suggest high treatment efficacy and adherence, there are no published data comparing these devices directly with continuous positive airway pressure (CPAP). Our objective is to evaluate if a convenient vibratory PT device is non-inferior to CPAP in POSA treatment.

Methods In this crossover randomised controlled trial, we enrolled patients with POSA with significant daytime sleepiness (Epworth Sleepiness Scale (ESS)≥10). POSA diagnosis was based on: (1) total Apnoea/Hypopnoea Index (AHI)>10/hour and non-supine AHI<10/hour (2) supine AHI≥2 × non-supine AHI. Patients used their initial allocated devices (PT or CPAP) for 8 weeks before crossing to the alternative intervention after a 1 week washout. The primary aim is to measure changes in ESS between the two treatments. Secondary outcomes include sleep study parameters and patient treatment preference ( NCT03125512).

Results 40 patients completed the trial between April 2017 and December 2018. Difference in ESS after 8 weeks of device use (PT minus CPAP) was 2.0 (95% CI 0.68 to 3.32), exceeding our predetermined non-inferiority margin of 1.5. AHI on CPAP was lower than with PT (4.0±3.2 vs 13.0±13.8 events/hour, respectively, p=0.001), although both were lower than at baseline. Time spent supine was significantly lower with PT than CPAP (p<0.001). 60% of patients preferred CPAP, 20% preferred PT, while 20% preferred neither device.

Conclusions The non-inferiority ESS endpoint for PT compared with CPAP was not met and the results were inconclusive. Future trials with larger sample sizes or in less symptomatic patients are warranted to provide further insight into the role of these new vibratory PT devices.

  • sleep apnoea

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  • Correction notice This article has been corrected since it was published Online First. The format of tables 1 and 3 have been corrected.

  • Contributors YM was the primary investigator of the study and was responsible for study design, data acquisition, data analyses and writing of the manuscript. KW was involved in study design, data analyses and manuscript writing. YHC was involved in study design, data analyses and manuscript review. All other authors were involved in data acquisition and collection and manuscript reviews.

  • Funding The study was funded by the National Medical Research Council, Singapore.

  • Disclaimer The sponsor had no role in study design, data collection, analysis, interpretation, manuscript writing nor the decision to submit for publication.

  • Competing interests None declared.

  • Patient consent for publication Not required.

  • Provenance and peer review Not commissioned; externally peer reviewed.

  • Data availability statement Data are available on reasonable request.

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