Gait speed after applying anodal-transcranial Direct Current Stimulation in people with Parkinson's disease? Preliminary results

Abstract

Objective: The objective of this study was to explore the effects of anodal‐tDCS with two different montages on gait speed in people with PD. Background: During the last few years, there has been an emerging interest in non‐pharmacological treatment of gait difficulties in Parkinson's disease (PD) due to the side effects of PD medications including dyskinesia, motor fluctuation and poor balance (1). Non‐pharmacological approaches, such as current physical rehabilitation strategies have only limited effectiveness in improving gait abilities in PD. Deep brain stimulation and functional neurosurgery are expensive, and have highly invasive nature and potential severe side effects. Transcranial Direct Current Stimulation (tDCS) is one of the non‐invasive and low cost approaches that might be beneficial in improving gait abilities in PD (2). Methods: Eight volunteer participants with PD (aged 40‐80 years; 3 women, 5 men; MDS‐UPDRS score: 39.03±10.50) participated in this cross‐over, sham‐tDCS controlled study. Participants were assigned to receive bilateral anodal‐tDCS (1 mA, 20 minutes) of the pre‐ and primary motor cortices (anode: 10×4 cm2) with either a small active cathode (4×4 cm2 ) or large functionally inert cathode (10×10 cm2) placed over the cerebellum, or sham‐tDCS in a random order while walking on a treadmill. The sham or two anodal‐tDCS conditions occurred in a randomized order over three sessions one week apart. Gait speed was measured using the Vicon Nexus system (2.6) on an even surface before and after each tDCS session. Results: The anodal‐tDCS over the pre‐and primary motor cortices with a large cathode electrode 10×4 cm2 combined with treadmill walking significantly increased gait speed when comparing post‐test versus pre‐test (1.09 ± 0.15, p <0.02). There were no significant between pre and post tests for either the sham‐tDCS or the anodal‐tDCS with an active cathode electrode. Conclusions: This finding suggests that bilateral tDCS of the pre‐and primary motor cortices with a functionally inert cathode electrode combined with treadmill walking may have short‐term therapeutic effects on gait speed. However, these effects need to be confirmed in a larger population of people with PD.