Effects of repetitive transcranial magnetic stimulation on gait disorders and cognitive dysfunction in Parkinson's disease: A systematic review with meta‐analysis

BACKGROUND: Repetitive transcranial magnetic stimulation (rTMS) is acknowledged to be crucial to manage freezing of gait (FOG) and cognitive impairment for patients with Parkinson's disease (PD), but its effectiveness is unclear. OBJECTIVE: To determine the effects of rTMS on FOG and cognitive function in people with PD and to investigate potential factors that modulate the rTMS effects. METHODS: Databases searched included PubMed, Web of Science, EMBASE, and the Cochrane Library from inception to December 31, 2021. Eligible studies include a controlled randomized clinical trial of rTMS intervention for FOG and cognitive dysfunction in PD patients. The weighted mean difference (WMD) with 95% confidence intervals (CI) were calculated with fixed‐effects models. The outcome of the study included gait and cognitive assessments. RESULTS: Sixteen studies with a total of 419 patients were included. Fixed‐effects analysis revealed that rTMS was effective in improving freezing of gait questionnaire scores (short‐term effect: WMD = −0.925, 95% CI: −1.642 to −0.209, p = .011; long‐term effect: WMD = −2.120, 95% CI: −2.751 to −1.489, p = .000), 10‐m walking time (short‐term effect: WMD = −0.456, 95% CI: −0.793 to −0.119, p = .008; long‐term effect: WMD = −0.526, 95% CI: −0.885 to −0.167, p = .004), Timed Up‐and‐Go scores (short‐term effect: WMD = −1.064, 95% CI: −1.555 to −0.572, p = .000; long‐term effect: WMD = −1.097, 95% CI: −1.422 to −0.772, p = .000), Montreal cognitive assessment (WMD = 3.714, 95% CI: 2.567 to 4.861, p = .000), and frontal assessment battery (WMD = −0.584, 95% CI: −0.934 to −0.234, p = .001). CONCLUSIONS: RTMS showed a beneficial effect on FOG and cognitive dysfunction in parkinsonism. However, the optimal rTMS protocol has not been determined and further high‐quality studies are needed.