Background: A systematic review and meta-analysis was performed to compare the outcomes of oral appliances (OAs) with those of CPAP in treatment of patients with obstructive sleep apnea (OSA).
Methods: Relevant studies were retrieved from the following electronic databases, up to and including September 2012: MEDLINE, PubMed, EMBASE, and Central Register of Controlled Trials. The main outcomes were Epworth Sleepiness Scale score, health-related quality of life, cognitive performance, blood pressure, apnea-hypopnea index (AHI), arousal index, minimum SpO2, percent rapid eye movement sleep, treatment usage, side effects, treatment preference, and withdrawals.
Results: Fourteen trials were finally included in this review. Our results demonstrated that the effects on Epworth Sleepiness Scale score (P = .31 and .09 in crossover and parallel-group trials), health-related quality of life, cognitive performance, and blood pressure of OAs and CPAP were similar. Besides, pooled estimates of crossover trials suggested a significant difference in favor of CPAP regarding AHI (P < .001), arousal index (P = .001), and minimum SpO2 (P < .001), while pooled estimates of parallel-group trials showed a significant difference in favor of CPAP regarding AHI (P < .001) and percent rapid eye movement sleep (P = .02). Moreover, OAs and CPAP yielded fairly similar results in terms of treatment usage (P = .26 for hours/night in crossover trials, and P = .14 for hours/night and P = .19 for nights/week in parallel-group trials), treatment preference, side effects, and withdrawals (P = .34 in parallel-group trials).
Conclusions: CPAP yielded better polysomnography outcomes, especially in reducing AHI, than OAs, indicating that OAs were less effective than CPAP in improving sleep-disordered breathing. However, similar results from OAs and CPAP in terms of clinical and other related outcomes were found, suggesting that it would appear proper to offer OAs to patients who are unable or unwilling to persist with CPAP.
Keywords: CPAP; meta-analysis; obstructive sleep apnea; oral appliances.