Testing the Elevation as Sleep Apnea Treatment (TEST)

The purpose of this study is to determine if the elevation of the head of the bed in patients with obstructive sleep apnea can decrease the apnea-hypopnea index. First the investigators will do a standard polysomnography and see if the patients are included analysing the criteria like apnea-hypopnea index equal or more than 5. Within 2 weeks the patient will do the second polysomnography but this will be with a elevation of the head of the bed (15 cm of elevation of the bed doing a inclination). Then the investigators will compare the data of apnea-hypopnea index in the standard polysomnography versus the index with the elevation of the head of the bed.

There are many researches that demonstrate that the position of the patient modified the apnea-hypopnea index(IAH). In supine position the IAH will increase comparing with lateral position during th sleep. However few studies were done with the elevation of the head of the bed. First the investigators will do a standard polysomnography and see if the patients are included analysing the criteria like apnea-hypopnea index equal or more than 5. Within 2 weeks the patient will do the second polysomnography but this will be with a elevation of the head of the bed (15 cm of elevation of the bed doing a inclination). Then the investigators will compare the data of apnea-hypopnea index in the standard polysomnography versus the index with the elevation of the head of the bed.The main outcome will be to analyze the apnea hypopnea index comparing standard polysomnography (sPSG) with elevated polysomnography (ePSG).

Compare the apnea hypopnea index with the patient in standard polysomnography and in elevated polysomnography (head of bed elevation)

head of bed elevation elevation the head of the bed with 15 cm (head of bed elevation) and compare the apnea-hypopnea index with the standard polysomnography

Apnea-Hypopnea Index compared by the polysomnography standard versus polysomnography with the elevation of the head of the bed

During the polysomnography there are sensors that detect the airflow by cannula pressure and thermistor. WIth those equipment during the all night the patient will be registered and seen if there is absence of flow (apnea) and/or reduction of flow (hypopnea). The apnea and hypopnea index is done by dividing the number of respiratory events by recording time in hours of sleep (events per hour).

Inclusion Criteria: Berlin questionnaire high risk Epworth score > 9 Obstructive Sleep Apnea with an index ≥ 5 events/hour on the polysomnography (The American Academy of Sleep Medicine Manual for the Scoring of Sleep and Associated Events: rules,terminology and technical specifications. American Academy of Sleep Medicine, 2012) Exclusion Criteria: younger than 18 years and older than 80 years BMI more than 40 Kg/m2 heart failure renal failure uncontrolled respiratory disease uncontrolled neurological disease