The purpose of this study is; compare respiratory function parameters and respiratory muscle strength in patients with MSA compare to healthy controls, and to evaluate the results of SNIP and PImax in measuring inspiratory muscle strength in MSA patients.

Multiple system atrophy (MSA) is a sporadic, neurodegenerative disease that begins in adulthood, progressive, unexplained. Brain stem degeneration is thought to play a role in respiratory symptoms such as stridor, sleep-related respiratory disturbances and respiratory failure in MSA patients. Respiratory disorders were emphasized and evaluated in MSA during the studies. However, the pattern of pulmonary anomalies or the performance of the inspiratory muscles is not well defined in the MSA.

Inspiratory muscle strength is assessed by voluntary or involuntary tests. The most commonly used reference values are the known maximal inspiratory mouth pressure (PImax) measurement for ease of use. In people with neuromuscular disease, the influence of the orofacial muscles can cause air leakage from the mouth. As a result, low values may be due to air escape which caused by true respiratory muscle weakness, submaximal effort or weakness of the facial muscles.

The purpose of this study is; compare respiratory function parameters and respiratory muscle strength in patients with MSA compare to healthy controls, and to evaluate the results of SNIP and MIP in measuring inspiratory muscle strength in MSA patients.

For this purpose; demographic information (sex, age, occupation, height, body weight ...), clinical and medical status, diagnosis date and Mini Mental Status Scale data of all participants will be recorded at the visit. Inspiratory muscle strength will be evaluated with sniff nasal inspiratory pressure and maximal inspiratory mouth pressure. Expiratory muscle strength will be evaluated with maximal expiratory mouth pressure (PEmax).

Inclusion Criteria:

• Being between 40-80 years old
• Have been diagnosed with MSA
• Being under drug treatment
• Being enlightened to participate in the study and filling in the consent form
• Respiratory disease or no history of occupational exposure to affect the respiratory system
• The absence of any physical or mental disability that will prevent the implementation of the tests
• Mini Mental Test score> 24

Exclusion Criteria:

• Any history of neuromuscular disease other than MSA
• Having a diagnosis of psychiatric illness
• Chronic obstructive pulmonary disease (COPD) diagnosis
• The patient is not cooperative
• dementia
• Nasal congestion