RESUMO
BACKGROUND@#Low back pain (LBP) is a prevalent and debilitating condition that poses a significant burden on healthcare systems. Acupuncture has been proposed as a promising intervention for LBP, but the evidence supporting its specific effect is insufficient, and the use of sham acupuncture as a control in clinical trials presents challenges due to variations in sham acupuncture techniques and the magnitude of the placebo effect.@*OBJECTIVE@#To investigate the magnitude of the placebo response of sham acupuncture in trials of acupuncture for nonspecific LBP, and to assess whether different types of sham acupuncture are associated with different responses.@*METHODS@#Four databases including PubMed, EMBASE, MEDLINE, and the Cochrane Library were searched through April 15, 2023, and randomized controlled trials (RCTs) were included if they randomized patients with LBP to receive acupuncture or sham acupuncture intervention. The main outcomes included the placebo response in pain intensity, back-specific function and quality of life. Placebo response was defined as the change in these outcome measures from baseline to the end of treatment. Random-effects models were used to synthesize the results, standardized mean differences (SMDs, Hedges'g) were applied to estimate the effect size.@*RESULTS@#A total of 18 RCTs with 3,321 patients were included. Sham acupuncture showed a noteworthy pooled placebo response in pain intensity in patients with LBP [SMD -1.43, 95% confidence interval (CI) -1.95 to -0.91, I2=89%]. A significant placebo response was also shown in back-specific functional status (SMD -0.49, 95% CI -0.70 to -0.29, I2=73%), but not in quality of life (SMD 0.34, 95% CI -0.20 to 0.88, I2=84%). Trials in which the sham acupuncture penetrated the skin or performed with regular needles had a significantly higher placebo response in pain intensity reduction, but other factors such as the location of sham acupuncture did not have a significant impact on the placebo response.@*CONCLUSIONS@#Sham acupuncture is associated with a large placebo response in pain intensity among patients with LBP. Researchers should also be aware that the types of sham acupuncture applied may potentially impact the evaluation of the efficacy of acupuncture. Nonetheless, considering the nature of placebo response, the effect of other contextual factors cannot be ruled out in this study. (PROSPERO registration No. CRD42022304416).
RESUMO
BACKGROUND@#The placebo response of sham acupuncture in patients with primary dysmenorrhea is a substantial factor associated with analgesia. However, the magnitude of the placebo response is unclear.@*OBJECTIVE@#This meta-analysis assessed the effects of sham acupuncture in patients with primary dysmenorrhea and the factors contributing to these effects.@*SEARCH STRATEGY@#PubMed, Embase, Web of Science, and Cochrane CENTRAL databases were searched from inception up to August 20, 2022.@*INCLUSION CRITERIA@#Randomized controlled trials (RCTs) using sham acupuncture as a control for female patients of reproductive age with primary dysmenorrhea were included.@*DATA EXTRACTION AND ANALYSIS@#Pain intensity, retrospective symptom scale, and health-related quality of life were outcome measures used in these trials. Placebo response was defined as the change in the outcome of interest from baseline to endpoint. We used standardized mean difference (SMD) to estimate the effect size of the placebo response.@*RESULTS@#Thirteen RCTs were included. The pooled placebo response size for pain intensity was the largest (SMD = -0.99; 95% confidence interval [CI], -1.31 to -0.68), followed by the retrospective symptom scale (Total frequency rating score: SMD = -0.20; 95% CI, -0.80 to -0.39. Average severity score: SMD = -0.35; 95% CI, -0.90 to -0.20) and physical component of SF-36 (SMD = 0.27; 95% CI, -0.17 to 0.72). Studies using blunt-tip needles, single-center trials, studies with a low risk of bias, studies in which patients had a longer disease course, studies in which clinicians had < 5 years of experience, and trials conducted outside Asia were more likely to have a lower placebo response.@*CONCLUSION@#Strong placebo response and some relative factors were found in patients with primary dysmenorrhea. PROSPERO registration number: CRD42022304215. Please cite this article as: Sun CY, Xiong ZY, Sun CY, Ma PH, Liu XY, Sun CY, Xin ZY, Liu BY, Liu CZ, Yan SY. Placebo response of sham acupuncture in patients with primary dysmenorrhea: A meta-analysis. J Integr Med. 2023; 21(5): 455-463.
Assuntos
Feminino , Humanos , Dismenorreia/terapia , Terapia por Acupuntura , Manejo da Dor , Agulhas , Efeito PlaceboRESUMO
The progress of Chinese clinical research on acupuncture and moxibustion in recent 10 years was reviewed and analyzed, and corresponding suggestions were put forward for the current problems. In the past 10 years, Chinese clinical research on acupuncture and moxibustion has made considerable progress, mainly in the following areas: a series of internationally recognized clinical research evidences have been published, a preliminary acupuncture clinical evaluation system has formed, sham/placebo acupuncture control is widely used internationally, acupuncture clinical research norms and standards have been initially established. However, the following issues still need to be paid attention to in follow-up research: focus on the overall layout and refinement of clinical research, further improvement of clinical evaluation system, developing relevant norms for sham/placebo acupuncture setting and reporting, strengthening data sharing and platform integration, building a smooth basic and two-way transformation clinical pathway, etc.