Deprenyl monotherapy improves visuo-motor control in early parkinsonism

Deprenyl is a potent MAO-B inhibitor which is commonly prescribed for treatment of parkinsonism. Despite prevalent use its effects on the symptoms and course of Parkinson's disease (PD) are still debated. The present study was therefore undertaken in order to measure quantitatively changes in visuo-motor control (VMC), consequent to deprenyl monotherapy in early PD. Previous work from our laboratory has shown typical VMC deterioration in PD patients, that correlates with disease severity. Thus, measurements of such changes provides a sensitive tool with which the symptomatic effects of drug treatment can be assessed quantitatively. Fourteen newly diagnosed, PD patients with light symptoms were studied. The VMC of all patients was tested after the first neurological examination, before drug treatment commenced. A second test was done after 30 days of treatment with deprenyl at a dose of 2.5 mg/day. Following this test, dosage was increased to 10 mg/day and a third VMC test was given after 30 more days of treatment. Our results show significant improvement in VMC functions following 30 days of 2.5 mg/day treatment and a continuing improvement after the next 30 days of 10 mg/day treatment. This improvement pertains mainly to directional control of self initiated movements and is smaller for movements that are guided externally. We conclude that deprenyl monotherapy has a clear symptomatic beneficial effect for patients with early PD.