The Effect of Methylphenidate on Non-motor Symptoms and Postural Control in Parkinson's Disease.

Overview

This project aims to determine if methylphenidate can improve deficits in attention and symptoms of orthostatic hypotension, two common non-motor symptoms, in patients with Parkinson's Disease. This project also seeks to evaluate the effect of methylphenidate on postural control in these patients, a debilitating motor symptom that places patients at an increased risk of falling. This study will build on existing data to support a new indication for the use of methylphenidate in Parkinson's Disease. Using standard and objective evaluations, this study will quantify the effect of methylphenidate at two doses on attention levels, orthostatic hypotension, and measures of postural control. Phase I of the study will compare methylphenidate 10mg three times daily to placebo and Phase II of the study, for those tolerating the lower dose in Phase I, will compare methylphenidate 20mg three times daily to placebo. By incorporating two different doses, the study also seeks to determine if any improvements are dose-related. Secondary endpoints will include safety assessments (adverse event monitoring and vital signs) performed every 30 minutes following supervised drug administration. Visual analog scales will be presented to each participant before treatment and following the final dose of each treatment to assess changes in fatigue. A secondary task will be added to postural tests to assess the influence of cognitive processes. It is hypothesized that methylphenidate will demonstrate a significant beneficial effect on all outcomes. It is projected that objective improvements will be observed following treatment with methylphenidate at both doses (10 and 20mg three time daily) when compared to placebo. It is further hypothesized that the effects will be dose-related and therefore more profound with higher doses.