Two recent reviews have evaluated the evidence for acupuncture as a means of preventing migraine attacks.
The first review assessed the efficacy and safety of acupuncture for the prophylaxis of episodic or chronic migraine in adult patients compared to pharmacological treatment.
The authors included randomized controlled trials published in western languages that compared any treatment involving needle insertion (with or without manual or electrical stimulation) at acupuncture points, pain points or trigger points, with any pharmacological prophylaxis in adult (≥18 years) with chronic or episodic migraine with or without aura according to the criteria of the International Headache Society.
Nine randomized trials were included encompassing 1,484 patients. At the end of the intervention, a small reduction was found in favor of acupuncture for the number of days with migraine per month: (SMD: -0.37; 95% CI -1.64 to -0.11), and for response rate (RR: 1.46; 95% CI 1.16-1.84). A moderate effect emerged in the reduction of pain intensity in favor of acupuncture (SMD: -0.36; 95% CI -0.60 to -0.13), and a large reduction in favor of acupuncture in both the dropout rate due to any reason (RR 0.39; 95% CI 0.18 to 0.84) and the dropout rate due to adverse event (RR 0.26; 95% CI 0.09 to 0.74). The quality of the evidence was moderate for all these primary outcomes. Results at longest follow-up confirmed these effects.
The authors concluded that, based on moderate certainty of evidence, we conclude that acupuncture is mildly more effective and much safer than medication for the prophylaxis of migraine.
The second review aimed to perform a network meta-analysis to compare the effectiveness and acceptability between topiramate, acupuncture, and Botulinum neurotoxin A (BoNT-A).
The authors searched OVID Medline, Embase, the Cochrane register of controlled trials (CENTRAL), the Chinese Clinical Trial Register, and clinicaltrials.gov for randomized controlled trials (RCTs) that compared topiramate, acupuncture, and BoNT-A with any of them or placebo in the preventive treatment of chronic migraine. A network meta-analysis was performed by using a frequentist approach and a random-effects model. The primary outcomes were the reduction in monthly headache days and monthly migraine days at week 12. Acceptability was defined as the number of dropouts owing to adverse events.
A total of 15 RCTs (n = 2545) could be included. Eleven RCTs were at low risk of bias. The network meta-analyses (n = 2061) showed that acupuncture (2061 participants; standardized mean difference [SMD] -1.61, 95% CI: -2.35 to -0.87) and topiramate (582 participants; SMD -0.4, 95% CI: -0.75 to -0.04) ranked the most effective in the reduction of monthly headache days and migraine days, respectively; but they were not significantly superior over BoNT-A. Topiramate caused the most treatment-related adverse events and the highest rate of dropouts owing to adverse events.
The authors concluded that Topiramate and acupuncture were not superior over BoNT-A; BoNT-A was still the primary preventive treatment of chronic migraine. Large-scale RCTs with direct comparison of these three treatments are warranted to verify the findings.
Unquestionably, these are interesting findings. How reliable are they? Acupuncture trials are in several ways notoriously tricky, and many of the primary studies were of poor quality. This means the results are not as reliable as one would hope. Yet, it seems to me that migraine prevention is one of the indications where the evidence for acupuncture is strongest.
A second question might be practicability. How realistic is it for a patient to receive regular acupuncture sessions for migraine prevention? And finally, we might ask how cost-effective acupuncture is for that purpose and how its cost-effectiveness compares to other options.