The causes of abnormal pulmonary function in Parkinson's disease.

Abstract

A significant obstructive ventilatory defect was detected in one third of 31 patients with severe Parkinson's disease. Patients with obstruction of expiratory flow had lower lung elastic recoil and higher airway resistance than patients writh normal expiratory flow despite similar degrees of neurologic impairment. The degree of air trapping and hyperinflation was similar in obstructed and nonobstructed patients as were thoracic and pulmonary compliances. After therapy with l-deoxyphenylalanine, significant neurologic improvement but no changes in expiratory flow or lung volume occurred. These data suggest that when expiratory flow obstruction occurs in Parkinson's disease, it is related to increased airway resistance or decreased lung elastic recoil consistent with coexisting chronic obstructive lung disease rather than to the neuromuscular dysfunction.