Repetitive transcranial magnetic stimulation for prophylactive treatment of chronic migraine: A randomised, single-blind, parallel-group, sham-controlled trial

Abstract

Background: Pilot studies suggest that repetitive transcranial magnetic stimulation could be effective in migraine. We studied its efficacy for prophylaxis of chronic migraine. Methods: We undertook a randomised, single-blind, sham-controlled study in patients with chronic migraine. Subjects were randomly allocated to sham, high-frequency repetitive transcranial magnetic stimulation (HF-rTMS) or low-frequency repetitive transcranial magnetic stimulation (LF-rTMS). The primary outcome was the reduction of attacks at four weeks. In addition, reduction of severity of headache based on the Visual Analogue Scale score at two & four weeks and a functional disability score at four weeks was recorded. Results: One hundred and eight patients were allocated to sham stimulation (n=36), HF-rTMS (n=36) and LF-rTMS (n=36) groups. The number of attacks per month decreased to 7.05+/-1.45 at four weeks post-rTMS in the HF-rTMS (p<0.001) as compared to the LF-rTMS (10.61+/-1.69) and sham (10.83+/-3.37) groups. The VAS score in the HF-rTMS group was significantly lowered (p < 0.001) from 8.61+/-1.15 at baseline to 6.63+/-0.96, and 7.19+/-0.98 at two and four weeks respectively. The duration of headache in hours over 4 weeks reduced from 32.4+/-14.9 to 11.6+/-6.14 in the HF-rTMS group (p<0.001), but did not change significantly in the LF-rTMS (30.4+/-11.9 to 27.8+/-14, p>0.05) and sham (26.8+/-11.06 to 37+/-15, p>0.05) in sham groups. There was no significant difference in functional disability between all the study groups at four weeks. Conclusion: High-frequency, but not low-frequency, repetitive transcranial magnetic stimulation may be useful in management of chronic migraine.