Magnetic Stimulation Treatment for Children with Migraine?
by Lauren Doyle Strauss, DO
Migraine is common in adolescents, with prevalence in the United States of approximately 5% in early adolescence, rising to approximately 8% in boys and 10% in girls by later adolescence. The impact of pediatric migraine can be substantial to children and their families with many missing school and their parents missing work to support them. Currently, topiramate is the only Food and Drug Administration (FDA)- approved preventive treatment for adolescent migraine which is an antiepileptic drug with possible cognitive and systemic side effects. The recent Childhood and Adolescent Migraine Prevention (CHAMP) study demonstrated that approximately 60% of children and adolescents with migraine who are treated with a preventive will improve, regardless of whether they are given prescription pharmacologic treatment (including topiramate) or placebo. This has highlighted the need to explore other treatment options for this patient population that may have less side effect burden.
There are several new exciting treatments within neuromodulation now available for patients who are interested in non-medication ways to treat or prevent pain. These devices can offer an alternative or be used in conjunction with other treatments to avoid drug interactions or additional side effects common to medication treatments. Single pulse transcranial magnetic stimulation (sTMS), supraorbital nerve stimulation (SONS), and vagus nerve stimulation (VSN) are noninvasive devices that are available for clinical use and FDA approved for the treatment of migraine, however, they had not been previously studied for this indication in the pediatric-aged population. A recent research study performed by a group of UCSF headache specialists with lead author Dr. Samantha Irwin, senior author Dr. Amy Gelfand and colleagues examined the feasibility of studying the sTMS device use in adolescent children funded through a grant from eNeura.
Transmagnetic stimulation has been also studied in treatment of other conditions such as depression or epilepsy. A large literature review lead by Dr. Donald Gilbert of Cincinnati Children’s Hospital on the safety of TMS in children was published in the Journal of Clinical Neurophysiology in 2004 titled “Should transcranial magnetic stimulation research in children be considered minimal risk?” His group reviewed 28 studies involving over 850 children who underwent single and paired pulse TMS protocols, which included healthy infants and children as well as children with a variety of CNS diseases and disorders including epilepsy. No seizures or other adverse events were reported. In general, however, since most studies did not report any adverse events, it is possible that minor side effects, such as headache or dizziness, are less likely to be reported in children than in adults. Magnetic ﬁeld strengths generated by TMS devices are 1.5-2 T, which is comparable to the ﬁeld strength of MRI scans. The sTMS device does generate a noise but it is thought to be no greater than what children might experience listening to music or from environmental exposures (100-120 dB). The sTMS device now has FDA approval for both acute and preventative therapy for adult patients due to the recent adult study looking at preventive use (ESPOUSE).
Dr. Samantha Irwin’s study published in the Headache Journal included adolescents (12-17 years) with migraine using sTMS twice daily in a preventative fashion, as well as additional pulses as needed. This was a small study with only 21 participants enrolled, 19 completed the baseline run in, and ultimately 12 completed the study. Using sTMS proved feasible in this age group and acceptable with overall high compliance once treatment administration was streamlined. Initially, participants were asked to give 2 pulses, wait 15 minutes, then give 2 additional pulses twice daily used as headache prevention. However, this 15 minute delay proved challenging for this age group, particularly on school days, and therefore was dropped. Study completion rate went from 4/13 (31%) to 7/8 (88%) once this change was made, P = .024. On average, participants used the device preventively between 22 and 24 days over a 28‐day block. Importantly, there were no serious adverse events and only two participants reported mild discomfort. Future studies of sTMS for migraine prevention or acute therapy in adolescents are needed to assess efficacy; and given the experience in this study, it will be essential in this age group to streamline treatment administration.