Transcutaneous occipital nerve stimulation (tONS) may offer a promising migraine prevention alternative for migraine sufferers who do not respond well to preventative drug treatments.
Migraine is a common and debilitating condition.It typically causes a severe pulsating headache on one side of the head which can last from a few hours to several days. A headache is often accompanied by nausea and sensitivity to light and sound. In some migraine sufferers, an attack can be preceded by a disturbance of vision –such as blind-spots or seeing flashing lights or zig-zag patterns. This is known as “migraine with aura”. The frequency and severity of migraine episodes vary from patient-to-patient.The Global Burden of Disease Study estimates that migraine is the third most common disease and the sixth leading cause of disability worldwide, affecting 14.7% of the general population. Because of this, finding methods for migraine prevention is important to study.
Some sufferers notice that certain things can trigger an attack – such as particular foods or drinks, hormonal changes in women, glaring light or changes in the weather. Although they can try to avoid these triggers, some patients may need to take drug treatments for migraine prevention. Currently, topirimate is the first-choice drug, but not all patients tolerate the drug well and alternative preventative approaches are needed. Several nerve stimulation techniques have been investigated with some success.However, some of these methods require surgical implants which may not be acceptable to patients who do not have severe migraine. A group of researchers in Beijing, China have investigated a technique stimulating the occipital nerve (at the back of the head) with electrodes on the skin surface. This technique is called transcutaneous occipital nerve stimulation (tONS). They recently reported the findings of their study in The Journal of Pain.
Patients with at least a one-year history of migraine without aura attending the outpatient clinic at the PLA General Hospital Beijing were invited to join the study. A total of 128 patients were randomly assigned to one of five groups – three groups receiving tONS at different electrical frequencies, one group receiving a shamtONS with non-conducting electrodes (placebo group), and one group receiving oral topiramate drug treatment.
The tONS groups received once daily therapy sessions with an electrical stimulator attached to two self-adhesive electrodes placed on the back of the head over the two occipital nerves. The intensity was adjusted appropriately and the stimulation lasted for 30 minutes. The topiramate group started at a dose of 25mg per day, increasing by 25 mg per day each week, to a maximum dose of 50 mg twice daily after four weeks.
All patients were asked to keep headache diaries for four weeks prior to starting treatment (baseline period) and during the four weeks of preventative treatment (treatment period). They were asked to note their migraine frequency, intensity, and duration. The groups were then compared to assess the 50% responder rate (at least a 50% reduction in monthly migraine days between baseline and one-month treatment periods) and headache characteristics.
Of the 110 patients who completed the study, the 50% responder rate was significantly higher in the three tONS therapy groups and the topirimate group compared with those in the placebo group. Headache intensity was also lower in the treatment groups compared to the placebo group. There was no significant difference in response amongst the tONS groups treated at different electrical frequencies
The researchers concluded that tONS therapy was a safe and effective new method of preventing migraine headache.This technique may offer a promising alternative to migraine sufferers who do not respond well to preventative drug treatments.
Written by Julie McShane, Medical Writer
Liu Y, Zhao D, Wang R, et al. Migraine prevention using different frequencies of transcutaneous occipital nerve stimulation: a randomized controlled trial. The Journal of Pain, Vol 18, No. * (August), 2017: pp 1006-1015. (Available online at :www.jpain.org and www.sciencedirect.com)