Effects of Inspiratory Muscle Training in Patients With Parkinson's Disease

Investigation of the Effects of Inspiratory Muscle Training on Oxygen Consumption, Muscle Oxygen and Physical Activity Level in Patients With Parkinson's Disease

Parkinson's patients usually have a significant decrease in respiratory muscle strength and respiratory function, which may increase in proportion to the severity of the disease. In addition, peripheral muscles may become dysfunctional by the rigidity caused by the disease. This reduces exercise capacity and may lead to a decrease in oxygen consumption. Respiratory muscle training has increased respiratory muscle strength in people with Parkinson's Disease (PD). However, its effectiveness on other functional outcomes has not been determined and studied.

Parkinson's disease is the second most common neurodegenerative disease. The main motor symptoms seen in Parkinson's disease are tremors, rigidity, bradykinesia, and decreased postural reflexes. In addition, respiratory problems that lead to death may often be seen. This is caused by dysfunction in the respiratory muscles and postural abnormalities, as well as changes in upper airway muscle activation and coordination. The coughing or exhaling reflex requires coordinated motor activity, and inadequate airway defence puts patients at risk for pneumonia. Aspiration into the lower airways results in a distinct series of events, including coughing and swallowing as the first attempt to clear the airway. Aspiration pneumonia is seen in Parkinson's patients because the coordination of these processes is unsuccessful, and the cough force is insufficient. Upper airway obstruction may occur due to stiffness and fatigue in the thyroarytenoid muscles. In addition, pathological processes such as bradykinesia, coordination disorder, and inspiratory muscle weakness can cause kyphoscoliosis and a decrease in lung volumes, resulting in restrictive respiratory function abnormality due to decreased chest wall compliance due to rigidity. In Parkinson's disease, respiratory muscles, like other skeletal muscles, are affected by stiffness, and weakness of the respiratory muscles makes it difficult to overcome this stiffness, resulting in reduced lung volumes. It is thought that this condition may develop due to the decrease in elastic retraction of the chest wall. In addition, mitochondrial dysfunction due to the pathogenesis of the disease also leads to deterioration in muscle oxygen metabolism. In individuals with reduced muscle oxygen, exercise tolerance and muscle strength decrease. Autonomic dysfunction of varying severity is observed in almost all patients, depending on the degeneration of spinal autonomic neurons or the side effects of dopaminergic that are part of pharmacological treatment. Patients may experience increased fatigue as well as autonomic dysfunction. Inadequate oxygen delivery and utilization to the muscles may limit skeletal muscle oxygenation and lead to increased use of anaerobic systems, resulting in fatigue. This causes a decrease in the level of physical activity and reduces the quality of life. However, studies investigating the effects of inspiratory muscle training in Parkinson's patients are insufficient. The aim of this study is to investigate the effects of inspiratory muscle training on maximum and functional exercise capacity, muscle oxygen, peripheral and respiratory muscle strength, respiratory muscle endurance, respiratory function, dyspnea, fatigue, cough strength, autonomic dysfunction, physical activity level and quality of life in patients with Parkinson's disease.For this purpose, our study was planned as a randomized, controlled, three-blind (investigators, patient, and analyzer) prospective study. According to the block randomization result, at least 20 patients with a diagnosis of Parkinson's Disease will be included in the training and control groups. Patients in the inspiratory muscle training group will be given inspiratory muscle strength training with the Powerbreathe device at 50% of the maximal inspiratory pressure for a total of 8 weeks, for a total of 30 minutes a day. Thoracic expansion exercises will be given to the control group as a home program for 8 weeks. All assessments will be completed in two days, before and after eight weeks of training.

Triple-blind study; the patients will not be informed about training group or control group and they will be evaluated and trained at different places and times.

Patients in the training group will be performed inspiratory muscle training with the PowerBreathe® (inspiratory muscle training device) device at 50% of the maximal inspiratory pressure.

Patients in the inspiratory muscle training group will be given inspiratory muscle strength training with the Powerbreathe® (inspiratory muscle training device) device at 50% of the maximal inspiratory pressure, 2 sets of 15 minutes a day for a total of 30 min/day or a single set of 30 min/day, 7 days/week for 8 weeks. Patients in the inspiratory muscle training group will continue their respiratory muscle strength training with a home program 6 days a week under the supervision of a physiotherapist 1 day a week. The MIPs of the patients will be re-measured every week and the training workload will be determined at 50% of the new maximal inspiratory pressure.

Thoracic expansion exercises will be given to the control group as a home program. The control group will be asked to do thoracic expansion exercises seven days/week and 120 times/day for eight weeks. The patients in the control group will be called once a week to check their home schedules, and they will be asked to keep a diary.

Maximal inspiratory (MIP) and maximal expiratory (MEP) pressures expressing respiratory muscle strength were

Respiratory muscle endurance will be assessed by the POWERbreathe Wellness (POWERbreathe, Inspiratory Muscle Training (IMT) Technologies Ltd., Birmingham, UK) device and the respiratory muscle endurance test at increased threshold load.

Pulmonary function will be evaluated using the spirometry, according to American Thoracic Society and European Respiratory Society criteria. Forced vital capacity (FVC) will be measured.

Pulmonary function will be evaluated using the spirometry, according to American Thoracic Society and European Respiratory Society criteria. Forced expiratory volume in the first second (FEV1) will be measured.

Pulmonary function will be evaluated using the spirometry, according to American Thoracic Society and European Respiratory Society criteria. FEV1 / FVC will be measured.

Pulmonary function will be evaluated using the spirometry, according to American Thoracic Society and European Respiratory Society criteria. Flow rate 25-75% of forced expiratory volume (FEF 25-75%) will be measured.

Pulmonary function will be evaluated using the spirometry, according to American Thoracic Society and European Respiratory Society criteria. Peak flow rate (PEF) will be measured.

Upper extremity exercise capacity will be evaluated with the six-minute pegboard and ring test (6-PBRT).

Cough strength will be assessed using a peak cough flow meter (PEFmeter) (ExpiRite Peak Flow Meter, China).

Health-related quality of life of patients will be evaluated with the Parkinson's Disease Questionnaire-39

Muscle oxygenation assessment will be performed using the Moxy monitor (Moxy, Fortiori Design LLC, Minnesota, USA).

Inclusion Criteria: Between the ages of 45-80, Follow-up with a diagnosis of Parkinson's disease for more than six months Stages I-III according to the modified Hoehn and Yahr scale Parkinson's patients with independent walking capacity will be included. Exclusion Criteria: Having a neurological disease other than Parkinson's disease Patients with a diagnosed lung disease that may affect respiratory functions At least 10 pack years or more of smoking history According to the American Association of Sports Medicine (ACSM) with absolute and relative contraindications to exercise tests Those with a Mini-Mental State Rating Scale score of less than 18 Patients with additional cardiac orthopaedic and psychological problems that limit the evaluation will be excluded from the study.

Gazi University, Faculty of Health Sciences, Department of Physiotherapy and Rehabilitation, Cardiopulmonary Rehabilitation Clinic

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