Acupuncture and moxibustion for irritable bowel syndrome: An umbrella systematic review

This umbrella review systematically examined the methodologic, reporting, and evidence quality of 15 systematic reviews on acupuncture and moxibustion for irritable bowel syndrome (IBS), a functional gastrointestinal condition characterized by abdominal pain and altered bowel habits that affects 3-15% of the world population. The study used standardized assessment tools: AMSTAR-2 for methodologic quality, PRISMA 2020 for reporting quality, and GRADE for evidence quality. The search was performed across eight databases through February 2023, including studies in Chinese and English. Of 342 publications identified, 15 systematic reviews were included, comprising 9 in Chinese and 6 in English, published between 2010-2022, with 6 to 31 randomized controlled trials each and samples ranging from 568 to 3,242 participants.

The methodologic results revealed serious deficiencies: only 2 studies showed low methodologic quality, while 13 had critically low quality according to AMSTAR-2. The main problems identified included lack of protocol registration, incomplete search strategies, absence of a list of excluded studies, inadequate consideration of risk of bias of included studies, and failure to assess publication bias. The assessment of reporting quality using PRISMA 2020 showed that 2 studies had severely deficient quality, 12 were partially deficient, and only 1 was relatively complete, with problems similar to those of the methodologic assessment. As for evidence quality, the GRADE analysis of 52 outcomes showed alarming results: no high or moderate quality evidence was found, with 10 low quality outcomes and 42 very low quality.

Downgrading factors included poor quality of included studies, problems with allocation concealment, inadequate randomization, lack of blinding, significant variability in outcomes across studies, small sample sizes, wide confidence intervals, and substantial heterogeneity. Despite these methodologic limitations, 12 of the 15 reviews concluded that acupuncture and moxibustion are effective for IBS, 3 suggested possible efficacy, and only 1 found insufficient evidence. Heterogeneity analysis showed that 46% of outcomes had no heterogeneity, 19% low, 13% moderate, and 21% high heterogeneity. The clinical implications are significant: although most of the evidence points to potential benefits of acupuncture and moxibustion in IBS treatment, including improvement of clinical symptoms, reduction of abdominal pain, and improvement in quality of life compared with controls, the low methodologic and evidence quality limits the reliability of these conclusions.

The authors emphasize that clinical decisions based on this evidence should be cautious and that more rigorous, multicenter, larger-scale clinical trials are needed, as well as high-quality systematic reviews, to obtain more robust evidence. The study highlights the importance of pre-registered protocols, comprehensive search strategies, appropriate risk of bias assessment, appropriate subgroup and sensitivity analyses, and assessment of publication bias in future research on acupuncture and moxibustion for IBS.