Acupuncture on 5-hydroxytryptamine levels and clinical outcomes in depression: A systematic review and meta-analysis of randomized controlled trials

BACKGROUND: neurotransmitter modulation. However, prior meta-analyses often considered manual and electroacupuncture together, increasing heterogeneity. This review focuses solely on traditional acupuncture to clarify its therapeutic role and provide evidence for standardized clinical application. AIM: To evaluate the efficacy of acupuncture in patients with depression and explore its feasibility as an adjunctive treatment. METHODS: Twenty randomized controlled trials on traditional acupuncture for depression-whose quality was assessed using the Cochrane tool-were included in this meta-analysis. Primary outcomes were the Hamilton Depression Rating Scale (HAM-D), Beck Depression Inventory-II (BDI-II), Self-Rating Depression Scale (SDS), and Montgomery-Åsberg Depression Rating Scale (MADRS). Secondary outcomes were the Pittsburgh Sleep Quality Index (PSQI), Hamilton Anxiety Rating Scale (HAMA), Self-Rating Scale for the Side Effects (SERS), and serum 5-hydroxytryptamine (5-HT) levels. RevMan 5.4 software was employed for the meta-analysis. RESULTS: Results revealed that acupuncture significantly reduced HAM-D, SDS, and MADRS scores. Although BDI-II scores improved in some studies, its overall effect was not statistically significant. Acupuncture also significantly improved HAMA and PSQI scores and increased serum 5-HT levels. Notably, SERS analysis indicated that acupuncture can significantly alleviate adverse reactions associated with antidepressants. However, most pooled results revealed substantial heterogeneity. CONCLUSION: The efficacy of traditional acupuncture improving symptoms, sleep, and anxiety and alleviating antidepressant side effects is highly encouraging. However, the low quality of the included studies warrants cautious interpretation.