Purpose: To compare the efficacy of tongue-retaining device (TRD) versus continuous positive airway pressure (CPAP) for treatment of obstructive sleep apnea (OSA).
Study design: Randomized crossover study.
Subjects and methods: Thirty-six patients with a mean age of 52.7 ± 10.6 years were enrolled. Inclusion criteria were age ≥ 18 years, apnea-hypopnea index (AHI) ≥ 5 events/h, and minimum oxygen saturation (SO2) ≥ 70% from polysomnography (PSG). Exclusion criteria were severe periodontal disease, unstable cardiopulmonary or neurological diseases, and/or total sleep time < 2 h. A 1-week wash-in period was followed by questionnaires and randomization into two groups: TRD/CPAP and CPAP/TRD (18 patients each). After 3 weeks of intervention, questionnaires were re-administered and WatchPAT was performed. After a 1-week wash-out period, patients were switched to the other treatment. Primary outcome was AHI. Secondary outcomes were SO2, Functional Outcomes of Sleep Questionnaire (FOSQ), and Epworth Sleepiness Scale (ESS) scores, treatment side effects, and adherence.
Results: Nine patients withdrew, so 27 patients were included in the final analysis. Mean AHI decreased from 38.7 ± 24.0 to 2.5 ± 0.5 and 12.7 ± 2.6 events/h for CPAP and TRD, respectively (95% confidence interval of mean differences 4.65-15.62; p < 0.001). There was no significant difference in ESS and FOSQ scores between treatments. Common adverse effects were drooling, tongue numbness, and pain for TRD; and nasal blockage, mask compression, and difficult portability for CPAP.
Conclusions: CPAP was superior to TRD for resolving PSG parameters; however, both similarly improved QOL and daytime sleepiness. TRD might be considered a short-term alternative treatment for OSA.
Trial registration: NCT02788487.
Keywords: Continuous positive airway pressure; Obstructive sleep apnea; TRD; Thai; Tongue-retaining device.