Common traditional Chinese medicine therapies for diarrhea-predominant irritable bowel syndrome: An overview of systematic reviews

Abstract

To critically evaluate and summarize the methodological quality of systematic reviews (SRs) and present objective and important outcomes on the effectiveness of traditional Chinese medicine (TCM) therapies, including Chinese herbal medicine (CHM), acupuncture, and moxibustion, for diarrhea-predominant irritable bowel syndrome (IBS-D). We conducted a comprehensive literature search for SRs in 7 databases until April 16, 2022. Two reviewers independently extracted data and assessed the methodological quality of the reviews according to the Assessing the Methodological Quality of Systematic Reviews 2 (AMSTAR-2), the Risk of Bias in Systematic reviews (ROBIS) tool, and the Preferred Reporting Item for Systematic Review and Meta-analysis (PRISMA) statement. The Grading of Recommendations, Assessment, Development, and Evaluation (GRADE) was used to rate the quality of evidence. IBS-D patients included in 12 reviews were diagnosed in accordance with the Rome criteria, 9 reviews focused on CHM, 2 articles observed moxibustion and heat-sensitive moxibustion, 1 article studied acupuncture and CHM. The outcomes of the SRs were the effectiveness rate, the total effectiveness rate, global symptom improvement, and adverse effects. Based on AMSTAR-2, which measures the quality of methodology, all of the included studies were of low or critically low quality. According to the ROBIS tool, 10 SRs (83.33%) had a high risk of bias. With the PRISMA checklist, only 3 SRs reached over 90% compliance. Based on GRADE, most evidence was of low quality, and there was a moderate quality of evidence that the effectiveness rate of modified-Tongxie Yaofang was superior to Western medicine in the treatment of IBS-D. Given the suboptimal reporting and methodological quality of existing SRs, more studies are needed to clarify whether TCM therapies are more effective or safe than pharmacological medicine. Future studies should combine evidence-based medicine with TCM research according to the characteristics of TCM.