Deep Brain Stimulation for Multiple Sclerosis Tremor: A Meta-Analysis

Abstract

Objectives To examine the effect of deep brain stimulation (DBS) on multiple sclerosis (MS)‐tremor, as measured by a normalized scale of tremor severity, with a meta‐analysis of the published literature. Methods Medline and EBSCO Host (January, 1998 to June, 2018) were systematically reviewed with librarian guidance, using the keywords “Deep brain stimulation” and “multiple sclerosis.” Bibliographies and experts in the field were also consulted to identify missed articles. All therapeutic studies on DBS for MS‐tremor, reported in the English language, within the study period were included. Papers that reported outcomes without a measure of central tendency and/or distribution were excluded. The papers were read in their entirety and graded for risk of bias according to the American Academy of Neurology (AAN) standards. To maximize statistical power, papers using different stimulation targets were grouped together. Outcomes were reported with the Fahn‐Tolosa‐Marin scale (FTM), the Bain‐Finchley scale (CRS) and 3‐ and 4‐point tremor severity scales and normalized with a Hedges g. Results The search produced 13 studies suitable for meta‐analysis. The random‐effects meta‐analysis showed that DBS improved the Hedges standardized mean tremor score by 2.86 (95%CI 2.03–3.70, p < .00001). Heterogeneity was high, with an I2 of 84%, suggesting that random effects model is more appropriate. Adverse event rates varied from 8% to 50%. Conclusions This meta‐analysis provides level III evidence that DBS may improve MS‐related tremor as measured by standardized tremor severity scales.

Deep-Brain Stimulation for Essential Tremor and Other Tremor Syndromes: A Narrative Review of Current Targets and Clinical Outcomes

“…MS-associated tremor appears to be less responsive to DBS than the previously discussed syndromes, although it can still be improved. In a meta-analysis of 13 studies including 129 DBS patients, stimulation improved the Hedges standardized mean tremor score by 2.15 [95]. This effect size is difficult to transpose into clinical scales, as it is a pooled estimate from heterogeneous outcome measures, but the largest study of combined Vim and Vo DBS demonstrated a 29.6% tremor reduction [53], while series of PSA DBS showed a 50-60% improvement on average [18].…”

The Fast Gray Matter Acquisition T1 Inversion Recovery Sequence in Deep Brain Stimulation: Introducing the Rubral Wing for Dentato-Rubro-Thalamic Tract Depiction and Tremor Control

“…A recent meta-analysis provided level III evidence that DBS is effective in the treatment of MS tremor. 17 However, the authors discussed a publication bias, and because of small studies, the effect reported may be overestimated. This may suggest that not every individual MS patient benefits from DBS.…”

Can Enhancing Neuronal Activity Improve Myelin Repair in Multiple Sclerosis?

“…Deep brain stimulation is the only direct stimulation method that has been tried in MS patients. Several studies have shown that thalamic deep brain stimulation significantly reduces tremor and improves quality of life in MS patients ( Hooper et al, 2002 ; Berk et al, 2002 ; Bittar et al, 2005 ; Thevathasan et al, 2011 ; Brandmeir et al, 2020 ). However, it is unlikely that the positive effects of deep brain stimulation on tremor symptoms rely on increased remyelination as the effects are seen quickly after stimulation.…”