More research needed on neurostimulation techniques in migraine

Many neurostimulation methods have been developed for the prevention and treatment of migraine and while some appear to be useful, the quality of available evidence for most is poor, according to a study published in The Journal of Headache and Pain.

“Although several techniques and devices appear to be effective ... larger well-conducted studies are still necessary for most to confirm their efficacy and determine their true effect sizes,” Xavier Moisset, MD, PhD, of the Centre Hospitalier Universitaire de Clermont-Ferrand, France, and colleagues wrote.

Moisset and colleagues conducted a systematic literature review and meta-analyses of randomized control trials on neurostimulation techniques for migraine.

All studies included had a comparison group with a minimum follow-up period of 4 weeks for preventive treatments and 2 hours for acute treatments. The studies also needed to have a minimum of 10 patients in each treatment group, assess pain as a primary or secondary outcome, and have been published as a full report.

Once identified, two review authors assessed each study for risk for bias using the GRAFE system. They categorized the quality of studies as “very high” if no bias was identified, “high” if there were one or two biases, “moderate” if there were three or four biases, and “low to very low” if there were five more biases.

A total of 38 studies were identified and included in the qualitative analysis, seven of which focused on acute treatments and 31 of which focused on preventive treatments. In the quantitative analysis, 34 studies — six on acute treatments and 28 on preventive treatments — were included in analyses.

Moisset and colleagues determined that remote electrical neuromodulation (REN) was effective for acute treatment of migraine, but data were insufficient to make conclusions on any other techniques because there were only single studies for each.

The researchers noted that the two studies assessing REN were conducted by the same group.

Moisset and colleagues also found that invasive occipital nerve stimulation was effective in migraine prevention and had a large effect size but had considerable heterogeneity. In addition, they found that supra-orbital transcutaneous electrical nerve stimulation, percutaneous electrical nerve stimulation, and high-frequency repetitive transcranial magnetic stimulation over primary motor cortex were all effective for migraine prevention, but the effect sizes observed for these techniques were small to medium.

The researchers said additional techniques — vagus nerve stimulation, left prefrontal cortex rTMS, and cathodal transcranial direct current stimulation over primary motor cortex — did not have a significant effect sizes and demonstrated high heterogeneity.

Based on their findings, Moisset and colleagues concluded that larger studies are needed to confirm the efficacy of most neurostimulation techniques to confirm their efficacy.

“As noninvasive neuromodulation is an emerging field in the treatment of migraine, an unbiased systemic review was important to understand what may really be benefitting patients,” Stephen Silberstein, MD, director of the Headache Center at Jefferson University Hospital in Philadelphia, said in a statement issued by Theranica, the manufacturer of Nerivio, the REN device assessed in the included studies.

“While the industry should conduct more studies to understand the potential of neuromodulation for migraine treatment, this study certainly helps comparing between the different emerging techniques,” he said. “REN, based on triggering conditioned pain modulation, stands out with very promising results for acute migraine treatment.”

References:

PR Newswire. Meta-analysis of Acute Migraine Treatment Devices Only Finds Conclusive Data for Nerivio's® REN Method. https://www.prnewswire.com/il/news-releases/meta-analysis-of-acute-migraine-treatment-devices-only-finds-conclusive-data-for-nerivios-ren-method-301191906.html. Accessed January 8, 2021.

Moisset X, et al. J Headache Pain. 2020;doi:10.1186/s10194-020-01204-4.