MONTREAL – Oral appliances are equally effective as continuous positive airway pressure therapy in patients with mild to moderate obstructive sleep apnea, but not in those with severe disease, according to a randomized trial.
“We've now shown clearly that oral appliances are a viable option that can be considered alongside CPAP [continuous positive airway pressure] therapy in mild to moderate cases,” Dr. Aarnoud Hoekema said in an interview. “Oral appliances are still a subject of much debate. In some clinics, they are used as secondary therapy only when CPAP therapy fails. Other clinics might use them only in patients with mild sleep apnea.”
His study, which he presented at the Eighth World Congress on Sleep Apnea, randomized 103 patients with obstructive sleep apnea to either CPAP (52) or oral appliance therapy (51).
Treatment effectiveness was evaluated by polysomnography after 8 weeks, and was defined as either a reduction in the apnea-hypopnea index (AHI) to below 5, or an AHI reduction to below 20 if this represented at least a 50% reduction in AHI and also rendered the patient symptom free.
A total of 50 patients were classified as having mild to moderate sleep apnea, defined as an AHI of between 5 and 30, while the remaining 53 patients had severe disease, with an AHI of more than 30, reported Dr. Hoekema, who is a dentist and research associate in the department of oral and maxillofacial surgery and maxillofacial prosthetics at Groningen University Hospital in Groningen, the Netherlands.
Overall, the study found that treatment was effective for most patients in both the oral appliance (76.5%) and the CPAP (82.7%) groups. In this comparison of the groups, oral appliance therapy met the predefined criterion for noninferiority, Dr. Hoekema said. But when the results were subanalyzed based on the severity of sleep apnea, oral appliance therapy was inferior in patients with severe disease, resulting in a 69% success rate, compared with 85% for CPAP. In the subgroup of patients with mild to moderate disease, oral appliance therapy was not inferior, with an 84% success rate, compared with an 80% success rate among patients using CPAP.
In mild to moderate patients, it might make sense to consider oral appliances first, he said.