Table 1.

Evidence for the use of acupuncture to to migraine

First author of study (year)	Groups studied and intervention	Results and findings	Conclusions
Coeytaux et al. (2016) [38]	For patients with migraine headaches, 22 studies were analyzed For patients with tension-type headaches, 12 studies were analyzed For patients with chronic headaches, 29 studies were analyzed	With regard to migraine headaches, the authors summarized the 2016 Cochrane Systematic Review (n = 22 studies, 4985 patients), which highlights acupuncture’s statistically significant symptomatic improvement at 2 months (compared with both drug treatment and usual care), and at the 3–4 and 5–6 month time-points (compared with usual care only)	Based on comparative studies from systematic reviews, there is evidence of the effectiveness of acupuncture as an adjunctive treatment for primary headache disorders. More studies are needed on the adverse effects and potential placebo effects
Li et al. (2020) [59]	15 Systematic reviews studying effectiveness of acupuncture for patients with migraine headaches	Based on the A MeaSurement Tool to Assess Systematic Reviews 2 (AMSTAR2) tool, 1 study was of low quality, while 14 studies were of critically low quality. Based on the Risk Of Bias in Systematic Reviews (ROBIS) tool, 9 studies had overall low risk of bias. Compared to sham medicine and Western medicine, acupuncture was observed to be more effective because it reduced usage of painkillers and reduced headache frequency/degree/duration	Based on various systematic reviews comparing acupuncture to sham acupuncture and Western medicine, acupuncture has been supported as an effective method of treating migraine headaches. However, the authors advocate for more improvement of study methodology
Xu et al. (2020) [49]	Multicentered (7 hospitals) randomized clinical trial with 150 acupuncture-naive patients presenting with episodic migraines without aura. Intervention: 20 acupuncture sessions vs. non-penetrative sham acupuncture	When compared to sham acupuncture, the 20-session acupuncture treatment yielded statistically significant differences in reducing migraine frequency (week 17–20) and duration (week 13–20)	This multicentered, randomized controlled clinical trial provides support for acupuncture treatment as an effective alternative treatment for patients with episodic migraines without aura. A limitation of the study is the lack of information on baseline drug prophylaxis on each patient
Zhang et al. (2020) [58]	7 RCTs on patients with migraines (± aura) comparing acupuncture to standard migraine prophylaxis	Several studies (4/7) showed statistically significant superiority of acupuncture over drug therapy	The authors comment how the heterogeneity and variability (e.g., acupuncture protocol, lack of management standardization) across the studies made it difficult to definitely endorse acupuncture; however, there is growing evidence showing the effectiveness and safety of acupuncture for migraine prophylaxis
Li et al. (2019) [56]	13 RCTs (n = 1559 patients) comparing electroacupuncture (EA) to various control methods (e.g., Western medicine, Sham-EA, blank control)	EA was observed to have a statistically significant improvement when compared with acupoint gut embedding, sham-EA, and acupuncture with sham-EA based on the VAS score (p < 0.05)	EA is an effective treatment for reducing migraine duration when compared with other forms of therapy; however, the lack of differences in adverse effects warrants further study
Zhang et al. (2019) [39]	15 Systematic reviews	Studies showed acupuncture to be more effective than drug therapy, sham acupuncture, and traditional Chinese m	Acupuncture has been reported to be useful in reducing migraine frequency, duration, and VAS score, which positions it to be a helpful treatment for prevention and management; however, the subjectivity of outcomes measures and low sample sizes highlight the need for more high-quality studies
Chen et al. (2020) [41]	19 RCTs (n = 3656)	Indirect comparison analyses show that acupuncture has advantages over propranolol in reducing migraine frequency, number of episodes, and adverse effects	Acupuncture may be considered to be a first-line agent for migraine prophylaxis someday given the preliminary data here showing its effectiveness and safety when compared to propranolol
Allais et al. (2019) [45]	Single-cohort study of EAP one session every 3 weeks for patients with chronic migraines (n = 20 women)	The mean reduction in the frequency of migraine episodes/month was 6.31 ± 4.64 days after 1 month; no significant reductions were observed in the second month. There were minimal adverse effects	The data provide support for using EAP as prophylaxis for chronic migraine patients. The authors note the small sample size and discuss how more frequent sessions may increase the treatment’s efficacy
Liao et al. (2020) [46]	Retrospective study on patients with migraines (n = 21,209) with 1:1 propensity score matching to control for various demographic information (e.g., sex, age, income). The comparison was between 1948 acupuncture users and 1948 non-acupuncture users	There was a statistically significant reduction in cumulative incidence of anxiety, depression, and medical expenditure in the acupuncture users cohort versus the non-acupuncture users cohort	The data provide support for using acupuncture in migraine patients with common comorbidities of depression and anxiety
Gu et al. (2018) [44]	Participants (n = 45) spread across 3 groups:  (1) Migraine without aura  (2) Cervicogenic headache  (3) Healthy controls The two patient groups received verum accupuncture, while the healthy controls received a sham treatment	There was a significant increase in N-acetylaspartate/creatine in the bilateral thalamus after acupuncture treatment in patients with migraines without aura, which was associated with a decrease in headache intensity score	Acupuncture significantly increases certain brain metabolites involved in the transmission of pain during migraines, which could explain how acupuncture is able to effectively relieve migraine-associated pain
Farahmand et al. (2018) [48]	Patients with diagnosis of acute migraine attacks (n = 60) Some patients received acupuncture, while some patients received a placebo	The acupuncture group had significantly lower pain scores at intervals up to 1 h post-treatment; however, there was no significant difference between the two groups at 2, 3, or 4 post-treatment	There is no significant difference in pain scores between the acupuncture group and the placebo group following intervention
Musil et al. (2018) [50]	Patients with a diagnosis of migraines Patients either received acupuncture (n = 42) or a standard pharmacological treatment (n = 44)	Number of migraine days was reduced more in the acupuncture than the medication group (5.5 vs. 2.0 days) after 12 weeks of intervention. Number of migraine days per 4 weeks was reduced more at the end of a 6-month follow-up in the acupuncture group (difference: − 4; 95% CI − 6 to − 2). Number of responders to the intervention was higher in the acupuncture group (50 vs. 27%; p < 0.05) at the end of the treatment period, and at the 6-month follow-up (81 vs. 36%; p < 0.001)	Acupuncture therapy can reduce symptoms and medication use in both the short- and long term, and serves as an effective alternative to pharmacological treatments for migraines
Naderinabi et al. (2016) [51]	Patients with the diagnosis of chronic migraine (n = 150) Patients received botulinum toxin-A, acupuncture, or sodium valproate 500 mg/day (control group)	Patients who received acupuncture had the greatest reduction in pain severity at the end of the 3-month study (p = 0.0001). In all groups, the number of days per month with migraine, absence from work, and the need for medication decreased during the evaluation period (p < 0.05), while acupuncture had the least amount of side-effects (p = 0.021)	The study concluded that while botulinum toxin-A injection, acupuncture, and pharmacological methods are all effective in treating chronic migraines, acupuncture is more effective and associated with fewer side effects than the other methods
Zhao et al. (2017) [52]	Patients with the diagnosis of migraine without aura (n = 249) Patients received acupuncture, sham acupuncture, or were placed on a waiting-list. Patients were followed for 24 weeks in total	At 16 weeks, the frequency of migraine attacks decreased the most with acupuncture (mean [SD] 3.2 [2.1]) compared with sham acupuncture (2.1 [2.5]) or with no treatment (1.4 [2.5]). The acupuncture group also had the significantly lowest frequency of migraine attacks, migraine days, and VAS scores at each follow-up time-point between weeks 4 and 24	True acupuncture might be more efficacious in the long-term treatment of migraines without aura compared with sham acupuncture or being on a waiting list
Jiang et al. (2018) [54]	62 RCTs involving 4947 total patients diagnosed with migraines (± aura) Patients either received no treatment, sham acupuncture, medication, or treatment acupuncture	The acupuncture group had lower VAS scores than the medication group at 1 month post-treatment (mean difference 1.22, 95% CI − 1.57 to − 0.87) and at 1–3 months post-treatment (− 1.81, 95% CI − 3.42 to − 0.20). The acupuncture group also had lower scores at 1 month post-treatment than sham acupuncture (− 1.56, 95% CI − 2.21 to − 0.92). Quality of life scores were higher with acupuncture than with sham acupuncture	Acupuncture is more effective at treating and preventing migraines than no treatment, sham treatment, and medication. Additionally, acupuncture is associated with a greater improvement of quality of life post-treatment than sham acupuncture
Xu et al. (2018) [55]	14 RCTs involving 1155 participants diagnosed with migraines without aura Participants received acupuncture, sham acupuncture, or medication	Acupuncture reduced migraine frequency (mean difference − 1.50, 95% CI − 2.32 to − 0.68; p < 0.001) and VAS score (0.97, 95% CI[0.63–1.31; p < 0.00001) more than medication, and had a higher effective rate with less adverse events. Acupuncture also reduced migraine frequency (− 1.05, 95% CI − 1.75 to − 0.34]; p = 0.004) and VAS score (− 1.19; 95% CI − 1.75 to − 0.63; p < 0.0001) more than sham acupuncture	While most of the results in his analysis favored acupuncture, the study concluded that because the quality of evidence supporting the findings from this study were low to very low, further studies are warranted to qualify the findings; however, the authors did conclude that acupuncture might be safer than medication in treating migraines without aura
Linde et al. (2016) [57]	22 Trials were included that involved a total of 4985l participants Patients either received no treatment, sham acupuncture, medication, or true acupuncture	Acupuncture reduced migraine frequency by at least half in 41% of participants compared to 17% with no treatment. Acupuncture at least halved migraine frequency in 50% of participants compared to 41% with sham acupuncture. Acupuncture at least halved migraine frequency in 57% of participants compared to 46% who received medication	Adding acupuncture as an adjuvant therapy to traditional treatments for migraines can reduce frequency of migraines
Wang et al. (2014) [47]	Patients that suffer from frequent migraine (n = 50) Patients were either assigned to a real acupuncture group or a sham acupuncture group	Real acupuncture compared to sham acupuncture was associated with significantly fewer migraine days (mean ± SD: 5.2 ± 5.0 vs. 10.1 ± 7.1; p = 0.008), less severe migraine (2.18 ± 1.05 vs. 2.93 ± 0.61; p = 0.004), more responders (19 vs. 7; p = 0.002), and increased pain thresholds after 20 weeks of treatment. These differences between the groups were maintained at the 3-month follow-up, but, not at the 12-month follow-up	Acupuncture is an effective and safe option in the short-term treatment of migraines; however, larger RCTs will have to be conducted to further evaluate the efficacy and safety of using acupuncture in the long-term to treat migraine headaches
Kuangshi et al. (2015) [60]	A total of 12 patients with MWoA were recruited to undergo resting-state fMRI scanning, with rescanning after 4 weeks of standard acupuncture treatment. Another 12 matched healthy control subjects underwent once scanning for comparison	Significantly decreased FC in the rFPN and the decreased FC could be reversed by acupuncture treatment. The changes of FC in MWoA patients was negatively correlated with the decrease of VAS scores after treatment. This study indicated that acupuncture treatment for MWoA patients was associated with normalizing effects on the intrinsic decreased FC of the rFPN	This study provided new insights into the treatment-related neural responses in MWoA patients and suggested potential functional pathways for the evaluation of treatment in MWoA patients. Future studies are still in need to confirm the current results and to elucidate the complex neural mechanisms of acupuncture treatment
Yang et al. (2015) (53)	10 RCTs with a total of 997 participants with the diagnosis of migraine Participants were placed in the verum manual acupuncture group or the sham acupuncture group	Verum acupuncture was more effective than sham acupuncture on the basis of having a greater reduction in the “not effective” rate (relative risk 0.24, 95% CI 0.15–0.38; p < 0.0001), and reduced recurrence rate (0.47 , 95% CI 0.28–0.81; p = 0.006). No significant differences were found between the groups in terms of headache intensity, frequency or duration, accompanying symptoms, or use of medication	While these findings suggest that verum acupuncture is superior to sham acupuncture in treating migraines, further large-scale RCTs are warranted to verify these findings

CI Confidence interval, EA electroacupuncture, EAP ear acupuncture, FC functional connectivity, fMRI functional magnetic resonance imaging, MWoA migraine without aura, RCT randomized clinical trial, rFPN right frontoparietal network, SD standard deviation, VAS visual analog scale