Transcranial Magnetic Stimulation Promotes Gait Training in Parkinson Disease

Abstract

Objective: To determine whether priming with 1 or 25Hz repetitive transcranial magnetic stimulation (rTMS) will enhance the benefits from treadmill training up to 3 months postintervention in people with Parkinson disease (PD), and to evaluate the underlying changes in cortical excitability.

Methods: This randomized double-blind, placebo-controlled trial was conducted between October 2016 and December 2018. Fifty-one participants with PD were randomized to receive 12 sessions of rTMS (25Hz, 1Hz, or sham) followed by treadmill training. All participants were assessed at baseline and 1 day, 1 month, and 3 months postintervention. Primary outcome was fastest walking speed, and secondary outcomes were timed up-and-go test (TUG), dual-task TUG (DT-TUG), motor section of the Movement Disorder Society-Unified Parkinson's Disease Rating Scale (MDS-UPDRS-III), and electrophysiological evaluation of cortical excitability by TMS.

Results: The 1 and 25Hz rTMS groups produced a greater improvement in fastest walking speed at 1 day and 3 months postintervention than the sham group. Only the 1 and 25Hz rTMS groups sustained the improvements in TUG, and had a significant improvement in DT-TUG and MDS-UPDRS-III for up to 3 months. Behavioral improvements correlated with increased cortical silent period and short-interval intracortical inhibition in both groups receiving real rTMS.

Interpretation: Priming with 1 and 25Hz rTMS can augment the benefits of treadmill training and lead to long-term motor improvement up to 3 months postintervention. The motor improvement at follow-up was associated with a normalization of cortical excitability, which in turn suggests an alteration of the homeostatic plasticity range. Rebalancing cortical excitability by rTMS appears critical for plasticity induction. ANN NEUROL 2020;88:933-945.

FIGURE 1:

Trial flow chart. Post = 1 day postintervention; Post_1m = 1 month postintervention; Post_3m = 3 months postintervention; rTMS = repetitive transcranial magnetic stimulation; TT = treadmill training.

FIGURE 2:

(A) Increase in fastest walking speed. (B) Reduction in timed up-and-go test (TUG) time. (C) Reduction in dual-task TUG time. (D) Reduction in motor section of the Movement Disorders Society–Unified Parkinson’s Disease Rating Scale scores. Post = 1 day postintervention; Post 1m = 1 month postintervention; Post 3m = 3 months postintervention. * denotes p < 0.05.

FIGURE 3:

(A) Change in slope of recruitment curve. (B) Change in cortical silent period. (C) Change in short-interval intracortical inhibition. Post = 1 day postintervention; Post 1m = 1 month postintervention; Post 3m = 3 months postintervention. * denotes p < 0.05.