Acupuncture-related adverse events: systematic review and meta-analyses of prospective clinical studies

Abstract

Objective: Overview on risks of acupuncture-related adverse events (AEs).

Design: Systematic review and meta-analyses of prospective studies.

Data sources: PubMed, Scopus and Embase from inception date to 15 September 2019.

Eligibility criteria for selecting studies: Prospective studies assessing AEs caused by needle acupuncture in humans as primary outcome published in English or German.

Data extraction and synthesis: Two independent researchers selected articles, extracted the data and assessed study quality. Overall risks and risks for different AE categories were obtained from random effects meta-analyses.

Main outcomes: Overall risk of minor AEs and serious adverse events (SAEs) per patients and per treatments.

Results: A total of 7679 publications were identified. Twenty-two articles reporting on 21 studies were included. Meta-analyses suggest at least one AE occurring in 9.31% (95% CI 5.10% to 14.62%, 11 studies) of patients undergoing an acupuncture series and in 7.57% (95% CI 1.43% to 17.95%, 5 studies) of treatments. Summary risk estimates for SAEs were 1.01 (95% CI 0.23 to 2.33, 11 studies) per 10 000 patients and 7.98 (95% CI 1.39 to 20.00, 14 studies) per one million treatments, for AEs requiring treatment 1.14 (95% CI 0.00 to 7.37, 8 studies) per 1000 patients. Heterogeneity was substantial (I2 >80%). On average, 9.4 AEs occurred in 100 treatments. Half of the AEs were bleeding, pain or flare at the needle site that are argued to represent intended acupuncture reaction. AE definitions and assessments varied largely.

Conclusion: Acupuncture can be considered among the safer treatments in medicine. SAEs are rare, and the most common minor AEs are very mild. AEs requiring medical management are uncommon but necessitate medical competence to assure patient safety. Clinical and methodological heterogeneity call for standardised AE assessments tools, clear criteria for differentiating acupuncture-related AEs from therapeutically desired reactions, and identification of patient-related risk factors for AEs.

Prospero registration number: CRD42020151930.

Keywords: adverse events; complementary medicine; general medicine (see internal medicine); pain management; quality in healthcare; risk management.

Conflict of interest statement

Competing interests: DI reports receiving honorarium and travel costs from non-profit academic organisations, physician chambers and universities for teaching and lecturing, and serving as president of the German Medical Acupuncture Association (Deutsche Ärztegesellschaft für Akupunktur, DÄGfA, a non-profit medical association). PB declares receiving honorarium and travel costs from non-profit academic organisations and universities for teaching and lecturing and being a member of the scientific advisory board of the DÄGfA. WZ and TS declare no other relationships or activities that could appear to have influenced the submitted work.

© Author(s) (or their employer(s)) 2021. Re-use permitted under CC BY-NC. No commercial re-use. See rights and permissions. Published by BMJ.

Figures

Figure 1

Flow diagram. designed according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses. AE, adverse event.

Figure 2

Risk of bias assessment. Risk of bias assessment was conducted according to Faillie et al. L, green (low risk of bias); U, yellow (unclear risk of bias); H, red (high risk of bias).

Figure 3

Meta-analyses of the overall risk of acupuncture-related AEs. Summary risk estimates for AEs were calculated as the number of patients or treatments with at least one AE relative to the total number of patients or treatments, respectively. Data on AE reports of patients and therapists from the article published by Weidenhammer et al in 2008 were handled separately. AE, adverse event.

Figure 4

Meta-analyses of the overall risk of SAEs related to acupuncture. Summary risk estimates for SAEs were calculated as the number of SAE cases relative to the total number of patients or treatments, respectively. Data from the article published by Weidenhammer et al in 2008 refer to the AE reports of the therapists. SAE, serious adverse event.

Figure 5

Meta-analyses of the overall risk of AEs requiring treatment. Summary risk estimates for AEs requiring treatment were calculated as the number of patients with such AE relative to the total number of patients. AE, adverse event.