MedicalResearch: What is the background for this study? What are the main findings?
Response: Snoring and obstructive sleep apnea are common in the population and these disorders continuously increase because of the ongoing obesity epidemic in many countries. Today, 34% of men and 17% of women in the US suffer from obstructive sleep apnea of all severities. Symptoms include daytime sleepiness, poor sleep quality, headache, insomnia and restless legs. In the longer term, a more severe sleep apnea is associated with serious consequences, such as hypertension, stroke, cancer, traffic accidents and early death.
Continuous positive airway pressure is a highly effective treatment for sleep apnea patients. Adherence problems, for instance from nasal stuffiness and claustrophobia reduces its effectiveness. An oral appliance holds the lower jaw forwards during sleep in order to reduce snoring and sleep apneas. This therapy has primarily been suggested for snorers and patients with mild and moderate sleep apnea. No previous placebo-controlled study has, however, evaluated this specific group of patients. Results from more severe sleep apnea patients have shown a good effect on sleep apneas. The effect of oral appliances on daytime symptoms is unclear. Symptomatic improvement is an important outcome for milder sleep apnea patients.
The primary aims of the present study were to study the effects on daytime sleepiness and quality of life of a custom-made, adjustable oral appliance in patients with daytime sleepiness and snoring or mild to moderate sleep apnea, i.e. the primary target group for this type of therapy. Secondary aims included the effects on sleep apnea, snoring and various other symptoms of sleep disordered breathing such as headaches and restless legs. We found that oral appliance therapy was effective in reducing sleep apneas, snoring and symptoms of restless legs. The apnea-hypopnea index was normal (<5) in 49% of patients using the active appliance and in 11% using placebo, with a numbers needed to treat of three. Daytime sleepiness and quality of life did not differ during active treatment and the placebo intervention. The patients experienced reduced headaches with active treatment, but the results did not differ from placebo. It was concluded, that a custom-made, adjustable oral appliance reduces obstructive sleep apneas, snoring and possibly restless legs. The efficacy on daytime sleepiness and quality of life was weak and did not differ from placebo in this group of patients.
MedicalResearch: What should clinicians and patients take away from your report?
Response: An oral appliance is highly effective in reducing obstructive sleep apneas and snoring. The treatment might also produce other benefits for the patients, such as reduced symptoms of restless legs. It is likely, that subgroups of patients who have specific sleep related symptoms such as headaches will benefit from this treatment, although this was not proven in the present study design.
MedicalResearch: What recommendations do you have for future research as a result of this study?
Response: More research of effects of oral appliances in subgroups of patients with more identified causes to daytime sleepiness or in patients with specific symptoms, such as headaches, insomnia or restless legs. This approach is facilitated by the ongoing research aiming at phenotyping sleep apnea patients in order to find more specific indications for the various treatment options.
Marklund M, Carlberg B, Forsgren L, Olsson T, Stenlund H, Franklin KA. Oral Appliance Therapy in Patients With Daytime Sleepiness and Snoring or Mild to Moderate Sleep Apnea: A Randomized Clinical Trial. JAMA Intern Med. Published online June 01, 2015. doi:10.1001/jamainternmed.2015.2051.
MedicalResearch.com Interview with: Marie Marklund, DDS senior lecturer Department of Odontology, Faculty of Medicine, Umeå University, & Sweden (2015). Custom Oral Appliance Reduced Sleep Apnea and Restless Legs