Raising Money for
2011 MRF Research Grantee
FINAL REPORT: Alternating Current Stimulation for the Acute Treatment of Migraine
In migraine treatment, although a broad range of pharmaceutical options exists, there is an increasing interest in non-pharmaceutical acute and prophylactic alternatives with lower side-effects and improved effectiveness than common medication. Transcranial electrical stimulation is one of these possibilities. The effect of the stimulation is probably based on the influence on cortical neuronal activity and therefore, with cortical spreading depression, thought to be the basis of the aura at the beginning of a migraine attack. In the present study, 46% of the treated patients had no pain 2 hours post-stimulation when inhibitory electrical stimulation over the primary visual cortex at the beginning of the attacks was applied. The placebo effect was high, reaching 29%, consistent with previously published pain research data. Interestingly, a subgroup of patients diagnosed with menstrual migraine benefited from the stimulation more than other types of migraine patients. In this group, 70% of the treated patients had no attacks during/after stimulation in the active stimulation group and 20% in the placebo group.
Hypothesis vs. Findings
The original protocol failed to reach significance between real and placebo stimulation groups. Altogether 78 migraine attacks were treated. Out of 50 real stimulations, 23 were successful, showing that in these 46% patients had no pain 2 hours post-stimulation. From 28 placebo stimulations, 8 were effective (29%). Thus, although we believe that with more patients, significance could be reached, we would instead suggest that the protocol be improved, since we now are quite confident that the used intensity was probably too low. We found that due to higher bone thickness about 3-4 times more stimulation intensity is needed at the visual cortex to reach similar effects that can be seen in the motor cortex.