In patients with Parkinson disease (PD) who have depression, repetitive transcranial magnetic stimulation (rTMS) over the dorsolateral prefrontal cortex (DLPFC) improves depression similar to treatment with selective serotonin reuptake inhibitors (SSRIs), but has no effect on motor function and cognition, according to a meta-analysis. The results were published in the International Journal of Neuroscience.
Studies were selected based on predefined inclusion and exclusion criteria, with quality assessed via the Jadad Scale. A total of 528 articles was reviewed, with 7 articles with Jadad scores ≥4 ultimately included in the analysis.
Studies selected for the meta-analysis were limited to randomized, double-blind, placebo-controlled trials. All participants had a clinical diagnosis of idiopathic PD. Studies were included that used rTMS alone or in combination with other treatments compared with sham-rTMS, antidepressant treatments, psychological therapies, or placebo. Depression scales and scores, including the Beck Depression Inventory and the Unified Parkinson’s Disease Rating Scale, were utilized in the meta-analysis.
Findings demonstrated that compared with the use of sham-rTMS, rTMS over the DLPFC improved depression, although there was no significant difference in benefit compared with SSRI therapy. rTMS over the DLPFC was not associated with improvement in motor function compared with sham-rTMS or SSRI treatment in patients with PD. Further, the studies that included neurocognitive measures demonstrated no significant difference between the use of rTMS and sham-rTMS.
The investigators concluded that future studies are warranted to explore the effects of rTMS on cognition in patients with PD. Additional, larger, randomized trials are needed in order to confirm and elucidate the results of this meta-analysis.
Wang HJ, Tan G, Zhu LN, Chen D, Xu D, Chu SS, Ling L. The efficacy of repetitive transcranial magnetic stimulation for Parkinson disease patients with depression [published online July 9, 2018]. Int J Neurosci. doi:10.1080/00207454.2018.1495632