Acupuncture versus tricyclic antidepressants in the prophylactic treatment of tension-type headaches: an indirect treatment comparison meta-analysis

Background Acupuncture showed better improvement than sham acupuncture in reducing attack frequency of tension-type headache (TTH), but its effectiveness relative to first-line drugs for TTH is unknown, which impedes the recommendation of acupuncture for patients who are intolerant to drugs for TTH. We aimed to estimate the relative effectiveness between acupuncture and tricyclic antidepressants (TCAs) through indirect treatment comparison (ITC) meta-analysis.Methods We searched Ovid Medline, Embase, and Cochrane Library from database inception until April 13, 2023. Randomized controlled trials of TCAs or acupuncture in the prevention of TTH in adults were included. The primary outcome was headache frequency. The secondary outcomes were headache intensity, responder rate, and adverse event rate. Bayesian random-effect models were used to perform ITC meta-analysis, and confidence of evidence was evaluated by using the GRADE approach.Results A total of 34 trials involving 4426 participants were included. Acupuncture had similar effect with TCAs in decreasing TTH frequency (amitriptyline: mean difference [MD] -1.29, 95% CI -5.28 to 3.02; amitriptylinoxide: MD -0.05, 95% CI -6.86 to 7.06) and reducing TTH intensity (amitriptyline: MD 2.35, 95% CI -1.20 to 5.78; clomipramine: MD 1.83, 95% CI -4.23 to 8.20). Amitriptyline had a higher rate of adverse events than acupuncture (OR 4.73, 95% CI 1.42 to 14.23).Conclusion Acupuncture had similar effect as TCAs in reducing headache frequency of TTH, and acupuncture had a lower adverse events rate than amitriptyline, as shown by very low certainty of evidence. Acupuncture showed better improvement than sham acupuncture in reducing headache frequency of tension-type headache (TTH), but the lack of comparisons between acupuncture and first-line drugs impedes recommendation of acupuncture for TTH.Our indirect treatment comparison meta-analysis found similar effect between acupuncture and tricyclic antidepressants (TCAs) in reducing TTH frequency with very low certainty of evidence.Similar effect between acupuncture and TCAs were also observed in reducing headache intensity with very low certainty of evidence.Acupuncture had a lower rate of adverse events than amitriptyline with very low certainty of evidence.