Expiratory Muscle Training in Patients With Parkinson's Disease

Respiratory difficulty is one of the primary factors leading to death in patients with Idiopathic Parkinson's Disease (IPD). The progressive degeneration of a family of segregated motor and non-motor circuits in the brain results in motor and non-motor dysfunction. Breathing and swallowing are well known to be affected in IPD, and attention to these functions is fitting since most patients eventually experience morbidity and even mortality as a result of this dysfunction. Patients with IPD typically become sedentary and lose endurance, maximal fitness levels and overall pulmonary function. Much of the research focus has been on the motor symptoms of IPD (tremor, rigidity, bradykinesia) yet the pulmonary complications are perhaps ultimately the most important disability. The inability to generate adequate respiratory pressure is responsible for reduced cough magnitudes and cough response times. Cough is critical for the clearance of foreign materials in the airway helping to reduce infiltration of bacteria and subsequent respiratory infection. With reduced cough function an increased risk for pulmonary disease due to a reduced ability to protect the airways occurs. Moreover, the recognized debilitating disruptions to voice and speech characteristics that limit communication, care taking, employment opportunities and social interactions are also a result of poor respiratory function. There are a number of promising outcomes from an expiratory strength-training program. By increasing expiratory muscle strength and expiratory pressure generation, effective breathing, clearance of the airway, production of a louder and clearer voice as well as improved swallowing can occur. These explicit outcomes are predicted based on our experience with the use of an innovative device-driven, home-based expiratory strength training program focused on the expiratory muscles of respiration.

The aims of this study are to: 1) Investigate the activity of expiratory muscle strength training (EMT) in patients with idiopathic Parkinson's disease (IPD), 2) Determine the effect of increased expiratory force generation on breathing, cough magnitude, speech production, and swallowing, 3) Determine the effect of increased expiratory force generation on the patient's perception of speech change, 4) Determine the effect of Dopamine-replacement therapy (Parkinson's medications) on breathing, coughing, speaking, and swallowing measures.