ObjectiveTo compare the outcomes associated with the use of probiotics, prebiotics, and synbiotics for the treatment of chronic constipation in adults.MethodsWe searched eight electronic databases from database inception to July 11, 2023, to identify randomized controlled trials (RCTs) that report efficacy and safety for the treatment of chronic constipation. The risk of bias in the included RCTs was evaluated according to the Cochrane tool, and the certainty of the evidence was assessed using the Confidence in Network Meta-Analysis framework. The analysis was conducted using R version 4.3.0.ResultsOut of the 37 RCTs, a total of 21 different types of interventions were reported, involving 3,903 patients. This NMA demonstrated that both prebiotics and synbiotics resulted in an increase in frequency of stool movements per week. Compared to placebo, lactulose (Mean difference [MD] = 3.39, 95% Confdence interval [CI] [1.13, 5.65], moderate certainty), mix2 (consisting of Lactulose and Bacillus coagulans) (MD = 3.63, 95% CI [1.37, 5.89], moderate certainty), mix6 (consisting of Lactulose and Bifidobacterium coagulans) (MD = 4.30, 95% CI [1.04, 7.54], low certainty), and mix7 (consisting of Lactulose, Bifidobacterium subtilis, and Enterococcus faecium) (MD = 4.58, 95% CI [1.35, 7.78], moderate certainty) exhibited a significant effect. Notably, mix7 demonstrated the highest probability of being the most effective intervention (94.8%). Furthermore, when compared to L. plantarum, four probiotics and two synbiotics showed significant advantages in the Patient Assessment of Constipation Symptoms (PAC-SYM) score. L. reuteri (MD = -13.74, 95% CI [-22.20, -4.66], very low certainty) exhibited a significant effect in improving the Patient Assessment of Constipation Quality of Life (PAC-QoL) score. In terms of safety, there were no statistically significant differences between the intervention and control groups in all adverse event analyses.ConclusionsModerate to very low evidence supports the use of lactulose and synbiotics to increase the number of weekly stool movements in patients, particularly highlighting the significant impact of synbiotics in increasing the number of weekly stool movements in patients with constipation. The use of L. paracasei showed improvements in PAC-SYM scores, while L. reuteri demonstrated enhancements in PAC-QoL scores.

To perform a systematic review and meta-analysis to evaluate the effectiveness and safety of probiotics in the treatment of constipation-predominant irritable bowel syndrome (IBS-C), we searched for randomized controlled trials (RCTs) comparing probiotic care versus placebos for patients with IBS-C in five comprehensive databases (March 2022). The risk of bias was assessed using the Cochrane Collaboration Risk of Bias Tool. RevMan 5.3 was used to perform a meta-analysis on stool consistency, abdominal pain, bloating, quality of life (QoL), fecal Bifidobacterium and Lactobacillus counts, and adverse events. The GRADE approach was used to evaluate the certainty of the evidence. Ten RCTs involving 757 patients were included. Only three studies were rated as having a low risk of bias. The meta-analysis results show that, compared to the placebo, probiotics significantly improved stool consistency (MD = 0.72, 95% CI (0.18, 1.26), p 0.05). The low-to-very low certainty evidence suggests that probiotics might improve the stool consistency of patients with IBS-C and increase the number of Bifidobacteria and Lactobacilli in feces with good safety. However, more high-quality studies with large samples are needed to verify the findings.

Objectives: To assess the efficacy of electro-acupuncture (EA) relative to sham electro-acupuncture (sham EA) in treating chronic severe functional constipation (CSFC). Methods: A comprehensive search for relevant studies published between January 1, 1951 and May 14, 2020 was conducted in PubMed, the Cochrane Library, Chinese Biomedical Literature Database, Web of Science, and EMbase. Two investigators independently selected studies, extracted data, and assessed the quality of the included studies. The software Endnote X9 was used for screening articles, and the Review Manager 5.3 for analyzing data. Results: The meta-analyses involved 6 studies and 1457 individuals. The pooled results favored the EA group for the increase of complete spontaneous bowel movements (CSBMs) per week in the fourth week (MD = 0.80, P = 0.001) during treatment, and further improved in the eight weeks (MD = 1.25, P < 0.001). During the follow-up period, significant changes in CSBMs per week were seen in the experimental group (MD = 1.38, P = 0.008); the effect decreased in the twelfth week (MD = 0.87, P < 0.001). There was no significant difference in the Bristol stool scale score between the two groups in the fourth week (MD = 0.40, P = 0.08), but significant differences were observed in the eighth week (MD = 0.40, P = 0.03). A significant reduction in patient assessment of constipation quality of life (PAC-QOL) score were observed in the EA group during treatment (SMD = -0.83, P < 0.001). No serious adverse events were reported. Conclusions: EA had favorable effects on CSFC, and the longer the treatment duration was, the better was the effect, but the effect showed a certain period of validity. However, the results may be influenced by the clinical heterogeneity of acupuncture points, depth of needling, intensity, and frequency of EA.