Abstract
BACKGROUND AND OBJECTIVE: Ankylosing spondylitis (AS) is a chronic inflammatory disorder affecting sacroiliac joints, vertebral structures, paraspinal soft tissues, and peripheral joints. This study systematically investigated the mechanism of action of inflammatory factors underlying combined acupuncture therapy for AS, evaluating its impact on clinical manifestations and immune parameters. METHODS: A comprehensive literature search was conducted across PubMed, Embase, Cochrane Library, SinoMed, CNKI, Wanfang, and VIP databases using keywords related to acupuncture and AS. Randomized controlled trials (RCTs) were screened using EndNote X9. The Cochrane RoB 2 tool, GRADE assessed methodological quality. Meta-analysis was performed in Stata 15.0, employing mean difference (MD), standardized mean difference (SMD), or relative risk (RR) with fixed- or random-effects models based on I(2) heterogeneity. Publication bias was evaluated via funnel plots and Egger's test, and subgroup analyses were conducted where applicable. RESULTS: Fifty-two RCTs were included, of which 20 exhibited low risk of bias. Meta-analysis demonstrated that acupuncture, alone or combined with medication, significantly reduced pain (VAS: MD = -1.26, 95% CI [-1.44, -1.09]), inflammatory markers (CRP: MD = -3.49, [-4.12, -2.85]; ESR: MD = -5.36, [-6.82, -3.89]), and morning stiffness duration (MD = -1.32, [-1.87, -0.78]). Improvements were also observed in BASDAI, BASFI, IL-1, IL-6, IL-17, TNF-α, and IgA levels. Heterogeneity was moderate to high (I (2): 59.70-90.00%). Subgroup analysis indicated that intervention design and treatment duration contributed to heterogeneity. No significant publication bias was detected for primary outcomes, though morning stiffness showed potential bias. Sensitivity analyses confirmed the robustness of inflammatory marker results. CONCLUSION: Acupuncture, particularly as an adjunct therapy, appears effective in alleviating clinical symptoms and reducing inflammatory activity in AS. However, high heterogeneity and variations in study design necessitate cautious interpretation. Further rigorously designed trials are warranted. SYSTEMATIC REVIEW REGISTRATION: https://www.crd.york.ac.uk/PROSPERO/view/CRD420251013146.