The study aim of the project is to investigate the differences in respiratory functions, orofacial muscle tone changes, anxiety/depression, and quality of life of the patients according to the severity of Obstructive Sleep Apnea Syndrome. At the same time, to examine the reliability of the use of the MyotonPro evaluation method, which takes place rapidly in the literature and clinic, in the orofacial pharyngeal muscle group.

Obstructive sleep apnea (OSA) syndrome is a common but often unrecognized disorder caused by pharyngeal collapse during sleep and characterized by frequent awakenings, disrupted sleep, and consequent excessive daytime sleepiness. Upper airway resistance increase during sleep and upper airway inspiratory muscle activity decrease especially during bursts of rapid eye movements in REM (Rapid Eye-Movements) sleep. In this study, the differences in respiratory functions, orofacial muscle tone changes, anxiety/depression, and quality of life of the patients according to the severity of Obstructive Sleep Apnea Syndrome will be investigated. The project is planned to be carried out with participants who applied to the Bitlis State Hospital Chest Diseases Clinic and were diagnosed with OSA by polysomnography and other diagnostic methods. Based on "the Apnea-Hypopnea Index OSA rating scoring for adult individuals", participants will be divided into three groups: mild, moderate, and severe OSA. Healthy participants will form the fourth group on the control level. The respiratory functions of the participants will be evaluated with spirometry and a standard application procedure will be used. With the MyotonPro device, the tone of the orofacial muscles (m. digastricus venter anterior and m. mylohyoideus, tongue and m. masseter, m. temporalis) will be evaluated and data transferred to the computer will be reported. In the muscle tonus evaluations, standardization in cervical positioning will be provided by a dual digital inclinometer. The Hospital Anxiety and Depression Scale (HAD) will be used to evaluate the anxiety/depression levels of the participants, and the Short Form-36 (SF-36), which is prescribed as the global gold standard, will be used in the assessment of the quality of life. MyotonPro reliability investigation will be done by two separate researchers. The researchers will perform measurements independently, at the baseline, and after 1 week. MyotonPro evaluations will be based on anatomical localization points. During the measurement, both researchers will use the standard positioning protocol at both evaluation times.

Inclusion Criteria:

• Age > 18 years old.
• Getting a diagnosis of OSAS with polysomnography.
• Agree to participate in the study.

Exclusion Criteria:

• Having respiratory system disease (COPD, asthma, bronchiectasis, lung cancer, etc.).
• Sedative, hypnotic drug intake. Use of medical supplements such as diazepam.
• Hypothyroidism, acromegaly.
• Diagnosis of a psychiatric illness.
• Uncontrolled arrhythmia causing symptoms or hemodynamic impairment.
• Pulmonary edema.
• Pregnancy

Primary care clinic in Bitlis.