The main objective of this study is to compare the change in the apnea-hypopnea index (AHI) in patients with mild to moderate sleep apnea without daytime sleepiness after 12 months of myofunctional therapy exercises with respect to the placebo group (the placebo group will be instructed in simulation exercises that do not alter the function or morphology of the upper airway)

Background: Alternative treatment therapies to positive upper airway pressure (CPAP) for obstructive sleep apnea syndrome (OSAS) have been developed in recent years. Myofunctional orofacial therapy (MFT) is one of these alternatives and consists of exercises that improve mobility and increase muscle strength of the orofacial structures that contribute to the etiopathogenesis of OSAS. To date, any study to treat sleep apnea patients under this therapy has been conducted in Spain. Moreover, its long-term effect has not been evaluated worldwide.

Main objective: to compare the reduction in the apnea-hypopnea index (AHI) in patients with mild to moderate sleep apnea without daytime sleepiness after 12 months of myofunctional therapy exercises with respect to the placebo group (the placebo group will be instructed in simulation exercises that do not alter the function or morphology of the upper airway) Methodology: A 12-month, randomized, parallel-group, clinical trial will be conducted. Patients with an AHI ≥ 5 events per hour assessed by a respiratory polygraphy (RP) will be randomized to a MFT treatment branch or to another placebo exercises branch. A speech therapist will instruct patients to perform the exercises in both groups for three months. At the end of this period, a RP will be performed on both groups and the same treatment that they were doing will be maintained at home. One year later, a new RP will be performed and changes in AHI, oximetry parameters and snoring will be compared in both groups, as well as sleepiness, quality of life and the degree of adherence to the treatment.

Inclusion Criteria:

• Patients over 18 and under 80 years old.
• Patients with apnea-hypopnea index from 5 to 29 assessed by a respiratory polygraphy.
• Absence of daytime sleepiness (Epworth sleepiness scale <12).

Exclusion Criteria:

• Refractory high blood pressure (blood pressure that is not controlled with three antihypertensive drugs, including a diuretic).
• Ictus, transient ischemic attack, neuromuscular diseases, acute coronary syndrome or hospitalization for worsening heart failure, in the previous 30 days.
• Professional drivers, profession of risk or respiratory failure.
• Previous surgical intervention for the treatment of sleep apnea (those patients who have refused treatment with CPAP or mandibular advancement devices after 1 month of not using them,could be included).