Long-term levodopa admnistration in chronic stroke patients. A clinical and neurophysiologic single-blind placebo-controlled cross-over pilot study

Purpose: Promising new rehabilitative approaches to improve the substantial motor disability associated with chronic stroke include pharmacotherapy to enhance motor recovery. We conducted a single-blind placebo-controlled crossover pilot study to investigate the effects of prolonged treatment with L-DOPA in stroke patients. Methods: Ten chronic (10-48 months) stroke patients received placebo or L-DOPA 100 mg daily for 5 weeks. During drug's treatment patients suspended physiotherapy. Patients underwent clinical evaluation (Rivermead Motor Assessment, Nine Hole Peg Test, and 10 meter walking test) and transcranial magnetic stimulation recordings from the affected and unaffected hemisphere (resting motor threshold, motor evoked potential amplitude and cortical silent period) before and after 5 weeks of treatment. Results: After L-DOPA treatment patients improved their walking speed (p < 0.01) and manual dexterity (p < 0.01) with the affected hand, the cortical silent period over the affected hemisphere lengthened (p < 0.01), while no changes were found in placebo-group. Conclusion: A 5-week course of oral L-DOPA in a single daily dose substantially improves motor performance in patients with chronic stroke and could do so by modulating motor cortical excitability (cortical silent period lengthening) suggesting that cortical inhibitory mechanisms have a role in motor recovery after stroke. Pharmacotherapy could be a useful therapeutic approach for chronic stroke patients.