Effects of withdrawal of antiparkinson medication on gait and clinical score in the Parkinson patient.

Objective testing of medication is needed in Parkinson's disease. Gait analysis and clinical evaluation were done before and after a 24-h withdrawal of Parkinson medication. Twelve patients with stable, mild to moderate idiopathic parkinsonism (Hoehn and Yahr 1-3; seven men and five women mean age 59.9 years, mean duration of disease 6 years) were tested with gait analysis walking in five different paces. Velocity of gait, stride length and stride frequency, as well as stride length at constant velocity were calculated. Regression coefficients for the relation between stride length and stride frequency were also calculated. Clinical scoring according to the Webster rating scale and Hoehn and Yahr were performed for each test. Clinical functional assessment with a specially designed rise and gait test, an arm cycle test and the wooden rods test were done. Evaluated clinical score increased significantly (p less than 0.05) using both clinical tests. Maximum gait velocity (p less than 0.01), stride length at max. velocity (p less than 0.01), and stride length at constant velocity (p less than 0.03) were significantly decreased without medication. Stride frequency did not change. In the functional assessment tests only performance on the arm cycle test (p less than 0.03) was less well performed without medication. There was correlation between clinical score, gait and clinical functional assessment. The methods used detected significant changes in variables of gait as well as clinical scoring and some of the clinical functional assessments when medication was withdrawn for a 24-h period. The methods were useful in evaluation of pharmacological treatment.