Traditional Chinese medicine interventions based on meridian theory for pain relief in patients with primary dysmenorrhea: a systematic review and network meta-analysis

To determine the comparative effects and safety of traditional Chinese medicine (TCM) interventions based on meridian theory for pain relief in patients with primary dysmenorrhea (PD). This is a systematic review with network meta-analysis. Randomized controlled trials (RCTs) comparing meridian-based TCM interventions with waitlist, placebo, western medicine, and conventional therapies for PD pain. A SUCRA was used to estimate the probability ranking for the effects of interventions. 57 RCTs involving 3,903 participants and 15interventions were included. Thirty-two RCTs were rated as low risk of bias. A network diagram was drawn with 105 pairs of comparisons. Compared with NSAIDs and waitlist, significantly better effects were found in acupressure [SMD = -1.51, 95%CI (-2.91, -0.12)/SMD = -2.31, 95%CI (-4.61, -0.02)], warm needling [SMD = -1.43, 95%CI (-2.68, -0.18)/SMD = -2.23, 95%CI (-4.43, -0.03)], moxibustion [SMD = -1.21, 95%CI (-1.85, -0.57)/SMD = -2.10, 95%CI (-3.95, -0.07)], and acupuncture [SMD = -1.09, 95%CI (-1.62, -0.55)/SMD = -1.89, 95%CI (-3.67, -0.11)]. No adverse events were detected. For PD pain, the effects of acupressure, acupuncture, warm needling, and moxibustion were superior to those of NSAIDs and waitlist. Oral contraceptive pill, electro-acupuncture, acupressure, and warm needling demonstrated higher probabilities of being better interventions. More high-quality clinical trials are needed to provide more robust evidence of this network. PROSPERO CRD42022373312.