Is Sham Acupuncture Equally Effective for Primary Insomnia? A Bayesian Network Meta-Analysis.

Purpose: To compare the efficacy differences between acupuncture and sham acupuncture in adult primary insomnia through Bayesian network meta-analysis, analyze the impact of different types of sham acupuncture on efficacy, and explore the basis for the control setting.

Methods: A literature search of seven databases, including PubMed and Embase, until April 23, 2025, included randomized controlled trials (RCTs) comparing AT with noninvasive sham acupuncture (NISA), superficial acupuncture (SA), and non-acupuncture therapy (NAT) for treating PI in adults. The statistical analyses were conducted using R (version 4.4.1) and Stata (version 15.1). The protocol was registered with the International Prospective Register of Systematic Reviews (CRD420251012912).

Results: This meta-analysis incorporated 33 RCTs encompassing 3004 participants, with most studies originating from China. The results showed that at the treatment endpoint and after 4 weeks, AT significantly improved subjective sleep quality (Pittsburgh Sleep Quality Index, PSQI) compared to SA and NISA, exceeding the minimum clinically important difference (MCID: 2.5 points). Specifically, at the endpoint, AT vs SA (MD: -3.66; 95% CI: -4.48 to -2.84) and AT vs NISA (MD: -4.35; 95% CI: -5.67 to -3) were significant, while differences among SA, NISA, and NAT were not. Based on the surface under the cumulative rank curve (SUCRA), AT ranked first (99.9%), followed by SA (47.8%), NAT (31.9%), and NISA (20.4%). No significant differences were found between AT, NISA, and SA regarding objective sleep parameters.

Conclusion: AT significantly improved subjective sleep quality in patients with PI, though its impact on objective sleep measures was limited. When designing RCTs of acupuncture for PI, NISA is recommended as the sham acupuncture control. However, due to geographical limitations, the study results may be difficult to generalize. Future research should focus on monitoring objective sleep parameters and conducting international, multicenter RCTs involving diverse cultural populations.