Oral Appliances Efficacious in Treating Severe Obstructive Sleep Apnea Patients
Objectives: The purpose of this study was to evaluate the effects of oral appliance (OA) therapy in people with obstructive sleep apnea (OSA) of varying severity (clinically categorized). These preliminary results are from a larger randomized controlled trial (RCT) comparing two popular, FDA cleared and Medicare reimbursed appliance designs (midline traction versus bilateral thrust).
Methods: The overall study design is a single center, cross-over RCT: 4-weeks/OA with 1-week washout interval. Adults diagnosed with OSA (N=63), who had an apnea hypopnea index (AHI) ≥ 15 events/hour, and had failed continuous positive airway pressure therapy were enrolled. OA treatment effects were evaluated relative to baseline polysomnography AHIs. OAs were initially titrated to 60% of maximum protrusion. Home sleep tests (NOX-T3, Vyaire Medical) were used to evaluate OSA events. The results of 19 subjects (mean age=64.6 years, 63% male) who completed the study are reported here. Linear regression and ANCOVA were utilized to analyze the progression of AHI in mild-moderate (MOD, N=8) and severe (SEV, N=11) participants over the two four-week periods of the study.
Results: Overall, a significant decline in AHI over 4 weeks was found (R-squared=.27, p <.001). Overall average decline was from 37.7 to 16.0. The slopes of the regressions for the MOD (-1.72) and SEV (-7.69) groups were significantly different (p <.05). R-squared was .20 and .40, respectively. Median AHI reduction was 46% and 69% in the MOD and SEV groups, respectively (difference, p<.05). Fifty percent had final AHIs ≤9.1 (MOD) and ≤13.3 (SEV).
Conclusions: The OA treatment effect in the SEV group was significantly more pronounced and predictable. Age and sex were not significant covariates. Both types of OAs significantly reduced AHI in mild-moderate, but especially in severe OSA patients, even though these appliances have not been recommended for those with severe OSA.
Supported by Baylor Oral Health Foundation