Abstract
STUDY OBJECTIVE: The prevalence of supine-dependent obstructive sleep apnea (sdOSA) in a general population ranges from 20% to 60%, depending on the criteria used. Currently, the prevalence and evolution of sdOSA once oral appliance therapy with a mandibular advancement device (OAm) has started is unknown. In addition, literature on the correlation between sdOSA and treatment success with OAm is not unequivocal. The first purpose of this study was to assess the prevalence of sdOSA before and under OAm therapy. Second, the conversion rate from non-sdOSA to sdOSA during OAm therapy was evaluated. The third and final goal was to analyze the correlation between sdOSA and treatment success with OAm therapy in the patient population. METHODS: Two hundred thirty-seven consecutive patients (age 48 ± 9 years; male/female ratio 173/64; AHI 20.1 ± 14.7 events/h; BMI 27.2 ± 4.3 kg/m(2)) starting OAm therapy were included. RESULTS: The prevalence of sdOSA before the start of OAm therapy, ranged from 27.0% to 67.5%. The prevalence of residual sdOSA under OAm therapy in this study ranged from 17.5% to 33.9%. Second, the conversion rate from non-sdOSA to sdOSA ranged from 23.0% to 37.5%. Third, the presence of sdOSA at baseline was not a significant factor for treatment success with OAm therapy. CONCLUSIONS: The results of this study indicate that the prevalence of sdOSA before and under OAm therapy is relatively high. One-third of patients shift from non-sdOSA to sdOSA. Finally, treatment success for OAm therapy was not significantly correlated with the presence of sdOSA at baseline.