Major Finding: A handheld transcranial magnetic stimulator eliminated migraine pain after 2 hours in 97% of patients with migraine and aura, compared with 65% of sham-treated patients; it was more effective in patients using migraine prevention drugs.
Data Source: A sham-controlled randomized trial of 201 patients.
Disclosures: Neuralieve Inc., maker of the device, funded the study. The lead author is a paid consultant and stockholder in the company. All of the other authors also have financial ties to the company.
Active stimulation of the cortex with a single-pulse, transcranial magnetic handheld device gave patients with migraine and aura increased freedom from migraine pain.
The device was especially effective in patients who took migraine prevention drugs, according to Dr. Richard Lipton of the Albert Einstein College of Medicine, New York, and his associates, who reported that at 2 hours after treatment, 97% of those in the active group were pain free, compared with 65% of those in the sham group.
“For patients who commonly have aura as a signal of an impending migraine, treatment with [the device] may abort progression of the attack and abate disabling pain and other symptoms,” wrote the authors (Lancet Neurol. 2010;[doi:10.1016/S1474-4422(10)70054-5]).
The portable machine delivers a brief magnetic pulse into the cortex of the brain, causing a counterclockwise flow of current. The intervention is thought to inhibit cortical spreading depression and thus prevent migraine from developing.
In a double-blind, sham-controlled trial, 201 patients with migraine and aura were randomized to either the actual device (102) or sham (99). They were instructed to apply the device below the occipital bone and deliver two pulses of energy as soon as possible after the onset of aura, and always within 1 hour. The patients were allowed to take migraine prevention drugs, but not analgesics, triptans, ergots, or other drugs that could confound pain assessment. They could take rescue drugs 2 hours after a treatment.
M ost of the patients were women (130); their mean age was 39 years. They had a mean of four migraine attacks a month. Of the total, 37 did not treat a migraine; the 164 who did were included in a modified intent-to-treat analysis.
Significantly more of the actively-treated than sham-treated patients were pain free 2 hours after treatment (39% vs. 22%, respectively). The difference in being pain free remained significant at 24 hours (29% active group vs. 16% sham group), and at 48 hours (27% vs. 13%).
Other migraine symptoms at 2 hours– nausea, photophobia, and phonophobia–were significantly less common in the active group, but only in patients whose pain level was moderate or severe at baseline. Among those with no or mild pain at baseline, there were no differences in those symptoms at 2 hours after treatment.
The investigators said use of migraine prevention drugs was significantly associated with a better 2-hour pain outcome. For those in the active group, the absolute risk reduction of pain at 2 hours was 32% for those who took the drugs and 8% for those who did not take them.
The device was well tolerated. One serious adverse event, a case of optic neuritis, occurred during the trial. It happened before a treatment, however, and so was deemed unrelated to the device.
One of the device's biggest benefits is that it is not invasive. “Treatment can be delivered to a circumscribed region of the brain, [in] contrast with drugs that are delivered systemically,” they wrote.
In an accompanying editorial, Dr. Hans-Christoph Diener said the findings were encouraging (Lancet Neurol. 2010; [doi:10.1016/S1474-4422(10)70063-6]). “The use of TMS could be a major step forward in [treating] migraine with aura, particularly in patients in whom presently available drug treatment is ineffective, poorly tolerated, or contraindicated.”
However, Dr. Diener, of the University of Duisburg-Essen, Germany, noted that caveats remain. TMS can theoretically trigger seizures, and should not be used in patients with concomitant epilepsy until the device has been investigated in such a population.
In addition, he noted that triptans are very effective and inexpensive medications. “Therefore, the manufacturer of the TMS device must show cost-effectiveness compared with standard drug treatment with triptans,” he said.