Comprehensive Respiratory Training Exercise Program in Obstructive Sleep Apnea

The apnea-hypopnea index will be obtained from the overnight Polysomnography (PSG) study. PSG will be performed in the sleep center of National Cheng Kung University Hospital. Less than 5 events/hour indicates normal; AHI between 5-14 events/hour indicates mild Obstructive Sleep Apnea(OSA); AHI between 15-30 events/hour indicates moderate OSA; and AHI more than 30 events/hour indicates severe OSA.

The average number of desaturation episodes per hour (oxygen desaturation index) will be obtained from the overnight Polysomnography (PSG) study. A decrease in the mean oxygen saturation of ≥4% that lasts for at least 10 seconds indicates an episode of desaturation.

Maximum oxygen consumption (Vo2max) will be measured using Cardiopulmonary Exercise Testing (CPET) which will be performed on a static bicycle. The average value of Vo2max in adults is approximately 27-48 mL/kg/min. A greater Vo2max value indicates a better physical fitness level.

Sonography will be performed over the participant's neck region to assess the changes in tongue muscle thickness during normal breathing, Müller's maneuver, functional tasks, and natural sleep.

The data on tongue thickness will be presented in millimeters. A greater value indicates a thicker in tongue.

Ultrasound shear-wave elastography will be performed to assess the changes in tongue-based stiffness. The data will be presented in kPa, with a greater value indicating an increase in tongue stiffness. The minimum value is 0 kPa and the maximum value is 220 kPa.

The tongue muscle strength will be measured using an Iowa Oral Performance Instrument (IOPI) device, model 2.2 (Northwest, Co., LLC, Carnation, WA, USA). The minimum score is 0 and a higher score indicates stronger in tongue muscle strength.

The tongue muscle endurance will be measured using an Iowa Oral Performance Instrument (IOPI) device, model 2.2 (Northwest, Co., LLC, Carnation, WA, USA). The data will be presented in seconds. The longer the duration of holding (more than 10 seconds), the greater in the tongue muscle endurance.

Jaw strength will be measured using a 'handheld' dynamometer (MicroFET○R2, Hoggan Scientific, USA). The data will be presented in kilogram-weight. The minimum score is 0 and a higher score indicates stronger in jaw strength.

Computer Tomography (CT) will be performed. The pharyngeal airway volume will be calculated from the hard palate to the epiglottis and the data will be presented in cm3. The minimum score is 0 and a higher score indicates greater in pharyngeal airway volume.

Computer Tomography (CT) will be performed. Cross section area on the tip of the epiglottis was measured and the data will be presented in cm2. The minimum score is 0 and a higher score indicates greater in the cross-sectional area of the region.

The distance between the anterior and posterior pharyngeal wall on the tip of the epiglottis will be measured and presented in cm. The minimal value will be 0 and the greater value indicates a greater distance between the anterior to posterior in this area.

The distance between the lateral distance on the tip of the epiglottis will be measured and presented in cm. The minimal value will be 0 and the greater value indicates a greater distance between the lateral wall.

Epworth Sleepiness Score(ESS) will be used to measure the daytime sleepiness of OSA patients. The total score of ESS range from 0-24. A score greater than 10 indicates greater daytime sleepiness.

The level of obstruction, the degree of obstruction, and the configuration of the obstructive will be identified through the drug-induced sleep endoscopy. The degree of obstruction ranged from 0 to 2. 0: no obstruction; 1: partial obstruction; 2: complete obstruction.

Sleep quality will be measured using Pittsburgh Sleep Quality Index (PSQI).The total score ranges from 0 to 21 with a higher total score equal to or more than 5 indicating worse sleep quality.

For respiratory muscle strength, maximal inspiratory pressure (PImax) will be measured using Respiratory Pressure Meter. Data will be presented in cmH2O. The minimal score will be 0, and a higher value indicates stronger in the inspiratory muscle.

For respiratory muscle strength, maximal expiratory pressure (PEmax) will be measured using Respiratory Pressure Meter. Data will be presented in cmH2O. The minimal score will be 0, and a higher value indicates stronger in the expiratory muscle.

The respiratory muscle function on the forced vital capacity (FVC) % predicted will be collected using spirometry. The normal value is between 80% to 120%; mild abnormality: is 70-79%; moderate abnormality: is 60-69%; severe abnormality: is less than 60%.

The respiratory muscle function on the Forced Expiratory Volume in one second (FEV1)/ forced vital capacity(FVC) will be collected using spirometry. The normal value for the FEV1/FVC % is equal to or greater than 70%; mild abnormality: 60-69%; moderate abnormality: 50-59%; severe abnormality: less than 50%.