Probiotics and synbiotics in chronic constipation in adults: A systematic review and meta-analysis of randomized controlled trials

Nonintravesical Interventions for Preventing Intravesical Recurrence in Patients With Nonmuscle-Invasive Bladder Cancer: A Systematic Review and Meta-Analysis

Despite currently used intravesical therapies in non-muscle-invasive bladder cancer (NMIBC), the rate of intravesical recurrence remains very high. We aimed to evaluate the effectiveness of adding nonintravesical interventions to standard intravesical therapies to prevent intravesical recurrence. In April 2024, 3 databases were queried for prospective studies evaluating nonintravesical interventions in addition to standard intravesical therapies for NMIBC (CRD42024490988). The primary outcome was intravesical recurrence-free survival (iRFS). Standard pairwise meta-analyses were performed using hazard ratios (HR) and 95% confidence intervals (95% CI) with a random-effects model. We identified 18 eligible studies (14 RCTs and 4 prospective trials) comprising 4,593 NMIBC patients, which investigated pharmacological interventions (eg, selenium, vitamins, Lactobacillus casei, celecoxib, metformin, mistletoe lectin) and lifestyle modifications (diet). The addition of Lactobacillus casei significantly improved iRFS (HR: 0.50; 95% CI: 0.34-0.73; P < .001). A high western diet pattern significantly worsened iRFS (HR:1.48, 95%CI:1.06-2.06, P = .03). The other nonintravesical interventions were not associated with iRFS. Our comprehensive review of the published literature highlights the need for further research into the efficacy of nonvesical interventions for NMIBC. While Lactobacillus was shown to improve iRFS in 2 RCTs, additional high-quality randomized studies are required to evaluate the effectiveness of other interventions.

An update and overview of the various health-related benefits of probiotics: A focus on clinical trials demonstrating efficacy, tolerability and use in patients with impaired glucose tolerance and type 2 diabetes

Recently, probiotics have been investigated as potential therapeutic agents for various diseases. Clinical studies using probiotics have been conducted in humans with impaired glucose tolerance and type 2 diabetes mellitus. Chronic inflammation plays a pivotal role in initiating insulin resistance in the pathogenesis of type 2 diabetes, leading to cardiovascular diseases. Intestinal dysfunction and inflammation have been postulated to trigger systemic chronic inflammation, and it is assumed that the suppression of inflammation in the intestine is the point of activity of probiotics. Therefore, in this review, among the randomised controlled trials that evaluated the effects of probiotics in patients with impaired glucose tolerance and type 2 diabetes, we selected trials that evaluated the indices of glycaemic control and inflammation-related markers. Some trials have shown that the probiotics administration improved glycaemic indices, such as HbA1c levels, and reduced C-reactive protein levels and proinflammatory cytokines, such as IL-6, in the blood, suggesting the suppression of inflammation. Two trials showed improvements in glycaemic indices, implying that they were mediated by IL-10, an anti-inflammatory cytokine. Although a correlation between the suppression of inflammation by probiotics and improvement in glycaemic control has not been documented, one trial revealed that glycaemic control worsened, accompanied by a decrease in anti-inflammatory cytokine levels, after probiotics were discontinued. Other studies have shown that probiotics can reduce blood endotoxin levels and increase intestinal mucin production. These findings suggest that probiotic administration has enormous potential to suppress chronic inflammation in metabolic disorders, leading to improved glycaemic control. Suppression of chronic inflammation has been speculated to prevent vascular diseases in type 2 diabetes.

Effects of Probiotics and Diet Management in Patients With Irritable Bowel Syndrome: A Systematic Review and Network Meta-analysis

CONTEXT

The efficacy of probiotics and diet management in irritable bowel syndrome (IBS) is controversial, and their relative effectiveness remains unclear.

OBJECTIVE

This study aimed to evaluate the effects of probiotics, diet management, and their combination on IBS.

DATA SOURCES

PubMed, Embase, Cochrane, and Web of Science were searched from inception to July 10, 2023, for relevant studies, including symptom relief, IBS-symptom severity score (-SSS), and IBS-quality of life measure (-QOL).

DATA EXTRACTION

Two investigators independently performed the data extraction and quality assessment.

DATA ANALYSIS

A network meta-analysis was performed using a frequentist approach and a random-effects model to estimate the relative risk (RR) and 95% CI.

RESULTS

Forty-four articles were eligible for this study. In relieving IBS symptoms, compared with a sham diet, a low-fermentable oligosaccharide, disaccharide, monosaccharide, and polyols (low-FODMAP) diet (RR: 3.22; 95% CI: 1.70-6.26) and low-FODMAP diet combined with probiotics (RR: 17.79; 95% CI: 3.27-112.54) significantly relieved IBS symptoms. The control group showed significantly lower effectiveness than the probiotics group (RR: 0.47; 95% CI: 0.32-0.69). According to the surface under the cumulative rank curve (SUCRA), a low-FODMAP diet combined with probiotics (80.4%) had the best effect in relieving IBS symptoms, followed by a low-FODMAP diet (70.8%), probiotics (65.1%), and a gluten-free diet (54.3%). In reducing the total IBS-SSS, the low-FODMAP diet (90.5%) was the most effective, followed by the low-FODMAP diet combined with probiotics (76.6%), probiotics alone (62.3%), and gluten-free diet (28.3%). In reducing total IBS-QOL, probiotics (72.1%) ranked first, followed by gluten-free (57.0%) and low-FODMAP (56.9%) diets. Probiotics (34.9%) were associated with the lowest risk of adverse effects.

CONCLUSION

A low-FODMAP diet combined with probiotics is most effective in relieving IBS symptoms. A low-FODMAP diet is the most recommended diet for alleviating IBS severity, and probiotics were associated with improving the QOL of patients with IBS, with the fewest adverse events.

SYSTEMATIC REVIEW REGISTRATION

PROSPERO registration no. CRD42024499113.

Understanding constipation as a geriatric syndrome

Constipation is common among older adults and significantly impacts their quality of life (QoL). Prior studies have extensively detailed constipation, but conceptualization of constipation as a geriatric syndrome is lacking. In this review, we provide an overview of constipation in the geriatric population and conceptualize constipation as a geriatric syndrome given its high prevalence, under-recognized status, and association with poor QoL and adverse outcomes among older adults. The conceptualization of constipation as a geriatric syndrome, as with frailty and delirium, highlights its importance and need for a multi-faceted approach. Future research is needed to 1) better define constipation, 2) explore the multifactorial nature of constipation in older adults and relationship with other geriatric syndromes, 3) include more older adults in pharmacological and non-pharmacological interventions for constipation, and 4) curate multidisciplinary care models. Appreciating constipation as a geriatric syndrome will yield tailored management strategies, ensure timely intervention, and avoid adverse outcomes.

Chronic constipation: focus on microbiome-targeted therapies with prebiotics, probiotics, and synbiotics

Chronic constipation is a global medical, social, and economic problem due to its negative impact on patients’ quality of life and increased risk of colorectal cancer, cardiovascular and cerebrovascular disorders. The gut microbiota plays an important role in the pathophysiology of constipation through its interplay with the immune system, enteral and central nervous system, representing a promising therapeutic target. Gut dysbiosis in patients with constipation is characterized by reduced relative numbers of bacteria producing lactate (Lactobacillaceae, Bifidobacteriaceae) and butyrate (Lachnospiraceae, Oscillospiraceae), as well as with increased numbers of those producing hydrogen sulfide (Desulfovibrionaceae) and methanogenic archaea (Methanobacteriaceae). The leading pathogenetic mechanism related to intestinal dysbiosis in chronic constipation, can be microbial metabolic abnormalities (metabolic dysbiosis) characterized by altered production of short-chain fatty acid, methane, hydrogen sulfide, tryptophan metabolites and by abnormal bile acid biotransformation. It has been proven that dysbiotic abnormalities of the intestinal microbiome play a role in the pathophysiology of constipation, which allows for the use of prebiotics, probiotics, and synbiotics for effective microbiome-modulating therapy in patients with chronic constipation. The proven role of dysbiotic abnormalities of the intestinal microbiome in the pathophysiology of chronic constipation determines the effectiveness of microbiome-modulating therapy (prebiotics, probiotics, synbiotics) in patients with this syndrome. Inulin is the most studied preboitic; it is a soluble food fiber that markedly contributes to the regulation of intestinal microbiota, stimulates the growth of beneficial bacteria, and production of anti-inflammatory metabolites. Inulin normalized the intestinal function in patients with chronic constipation increasing the stool frequency, softening the stool, and reducing the intestinal transit time. In addition, inulin modulates the immune response and impacts the absorption of minerals, appetite, and satiety. Treatment with probiotics is also associated with reduced intestinal transit time, compared to controls. According to a systematic review and meta-analysis of 30 randomized controlled trials, only Bifidobacterium lactis strains (but not other probiotics) significantly increase stool frequencies in chronic constipation in adults. Clinical studies have shown that the targeted probiotic Bifidobacterium lactis HN019 can significantly increase the stool frequencies in patients with low (≤ 3 per week) stool frequency up to 4.7–5.0 per week, reduce the intestinal transit time and the rate of functional gastroenterological symptoms in adults with constipation. Beyond its clinical effects, Bifidobacterium lactis HN019 leads to beneficial changes in intestinal microbiota, significantly increasing the bifidobacteria and decreasing the enterobacteria numbers. The results of trials confirm the importance of synbiotic correction of dysbiotic microbiota in all patients with constipation to increase stool frequencies and improve fecal consistency, as well as to prevent the chronic disorders associated with constipation. Synbiotics, such as a combination of Bifidobacterium lactis HN019 and inulin, with the properties of both complementary and synergic synbiotic, may have the greatest microbiome-modulating and functional potential to significantly improve clinical outcomes in patients with chronic constipation compared to probiotics or prebiotics used alone.

Eight-Week Supplementation With Bifidobacterium lactis HN019 and Functional Constipation: A Randomized Clinical Trial

Importance

Probiotic supplementation may improve bowel movements. However, large, properly designed studies are lacking.

Objective

To evaluate the potential benefit of Bifidobacterium animalis subsp lactis HN019 on constipation, expressed as complete spontaneous bowel movements (CSBMs).

Design, Setting, and Participants

This randomized triple-blind placebo-controlled clinical trial with 2 weeks of run-in and 8 weeks of intervention was conducted from December 25, 2020, to February 28, 2022, at 5 hospitals in Shanghai, China. Participants included healthy volunteers with functional constipation according to Rome III criteria, 18 to 70 years of age, and a body mass index (calculated as the weight in kilograms divided by the height in meters squared) of less than 30.0. Eligibility after the run-in phase required the randomized participants to have 3 or fewer CSBMs/wk. Data were analyzed from September 29, 2022, to March 23, 2023, and reported as intention to treat.

Intervention

Participants were randomized to receive probiotic (B lactis HN019, 7.0 × 109 colony forming units (CFU)/d in maltodextrin at the start of the study and 4.69 × 109 CFU/d at the end of the study or maltodextrin placebo once a day for 8 weeks.

Main Outcomes and Measures

Primary outcome was change in CSBMs. Secondary outcomes included use of rescue medication, stool consistency, degree of straining for each bowel movement, abdominal pain, and bloating. Further, dietary habits and physical activity were recorded. Fecal samples were analyzed for moisture content, short-chain fatty acids, branched-chain fatty acids, microbiota composition, and calprotectin.

Results

Of the 283 individuals assessed for eligibility, 229 were randomized to either the placebo (n = 117) or the HN019 (n = 112) group. One participant in the placebo group discontinued due to COVID-19 restrictions. The 229 participants (194 [84.7% female) had a median age of 45 (38-52) years, mean (SD) BMI of 22.8 (2.5), and a mean (SD) of 0.77 (1.0) CSBM/wk. There was no difference in the change of weekly CSBMs from baseline to the end of study between the HN019 (least-square mean change, 0.80 [95% CI, 0.54-1.05]) and placebo (least-square mean change, 0.66 [95% CI, 0.41-0.90]) groups.

Conclusions and Relevance

Although probiotics have been reported to improve bowel function, this large, well-conducted randomized clinical trial did not confirm such results. Daily consumption of B lactis HN019 at the tested dose of 4.69 × 109 CFU did not outperform placebo to increase CSBMs.

Trial Registration

Chinese Clinical Trial Registry Identifier: ChiCTR2000029215.

Network meta-analysis of probiotics, prebiotics, and synbiotics for the treatment of chronic constipation in adults

OBJECTIVE

To compare the outcomes associated with the use of probiotics, prebiotics, and synbiotics for the treatment of chronic constipation in adults.

METHODS

We 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.

RESULTS

Out 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.

CONCLUSIONS

Moderate 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.

Effects of probiotics supplementation in gastrointestinal complications and quality of life of patients with systemic sclerosis: A systematic review

Background

Systemic sclerosis (SSc), as an autoimmune rheumatic disease characterized by immune dysregulation and vasculopathy, affects multiple organs. Due to the high burden of its symptoms on the health care system, this study aims to investigate the effects of probiotic supplements in patients with SSc.

Methods

We searched electronic databases with predefined search terms in PubMed, Scopus, and ISI Web of Science up to June 2023. Randomized controlled trials that evaluated the effects of probiotic supplementation in adult patients suffering from SSc were included in the study. Results of the included studies were reported as weighted mean difference (WMD) with a 95 % confidence interval (CI).

Results

Four studies met the inclusion criteria and were included in the meta-analysis. There was a total of 176 SSc patients. The results show a significant effect of probiotics supplementation on gastrointestinal (GI) symptoms containing reflux (WMD: -0.36, 95 % CI: -0.51 to -0.22, p-value <0.001), gas and bloating (WMD: -0.88, 95 % CI: -1.05 to -0.7, p-value<0.001). However, the results for constipation (WMD: -0.12, 95 % CI: -0.27 to 0.04, p-value = 0.13), diarrhea (WMD: -0.14, 95 % CI: -0.31 to 0.03, p-value = 0.10), and fecal incontinence (WMD: 0.04, 95 % CI: -0.06 to 0.15, p-value = 0.43) were insignificant.

Conclusion

Supplementing with probiotics may alleviate a few numbers of GI complications in SSc. Nevertheless, due to the limited number of studies, more well-designed studies are needed to strengthen these results.

Evidence-Based Clinical Guidelines for Chronic Constipation 2023

The Japan Gastroenterological Association published the first version of its clinical guidelines for chronic constipation 2023. Based on the latest evidence, these guidelines describe the definition, classification, diagnostic criteria, diagnostic testing methods, epidemiology, pathophysiology, and treatment of chronic constipation. They include flowcharts for both diagnosis and treatment of chronic constipation. In the treatment of chronic constipation, the first step involves differentiating between secondary forms, such as organic disease-associated constipation, systemic disease-associated constipation, and drug-induced constipation. The next step is to determine whether the chronic constipation stems from a motility disorder, a form of primary chronic constipation. For functional constipation and constipation-predominant irritable bowel syndrome, treatment should be initiated after evaluating symptoms like reduced bowel movement frequency type or defecation difficulty type. The first line of treatment includes the improvement of lifestyle habits and diet therapy. The first drugs to consider for oral treatment are osmotic laxatives. If these are ineffective, secretagogues and ileal bile acid transporter inhibitors are candidates. However, stimulant laxatives are exclusively designated for as-needed use. Probiotics, bulk-forming laxatives, prokinetics, and Kampo medicines, for which there is insufficient evidence, are considered alternative or complementary therapy. Providing the best clinical strategies for chronic constipation therapy in Japan, these clinical guidelines for chronic constipation 2023 should prove useful for its treatment worldwide. The Japan Gastroenterological Association published the first version of its clinical guidelines for chronic constipation 2023. Based on the latest evidence, these guidelines describe the definition, classification, diagnostic criteria, diagnostic testing methods, epidemiology, pathophysiology, and treatment of chronic constipation. They include flowcharts for both diagnosis and treatment of chronic constipation. In the treatment of chronic constipation, the first step involves differentiating between secondary forms, such as organic disease-associated constipation, systemic disease-associated constipation, and drug-induced constipation. The next step is to determine whether the chronic constipation stems from a motility disorder, a form of primary chronic constipation. For functional constipation and constipation-predominant irritable bowel syndrome, treatment should be initiated after evaluating symptoms like reduced bowel movement frequency type or defecation difficulty type. The first line of treatment includes the improvement of lifestyle habits and diet therapy. The first drugs to consider for oral treatment are osmotic laxatives. If these are ineffective, secretagogues and ileal bile acid transporter inhibitors are candidates. However, stimulant laxatives are exclusively designated for as-needed use. Probiotics, bulk-forming laxatives, prokinetics, and Kampo medicines, for which there is insufficient evidence, are considered alternative or complementary therapy. Providing the best clinical strategies for chronic constipation therapy in Japan, these clinical guidelines for chronic constipation 2023 should prove useful for its treatment worldwide.

The Anti-Constipation Effect of Bifidobacterium Longum W11 Is Likely Due to a Key Genetic Factor Governing Arabinan Utilization

Recent investigations have highlighted, both experimentally and clinically, that probiotic strains equipped with arabinofuranosidase, in particular abfA and abfB, favor regular intestinal motility, thus counteracting constipation. By analyzing the gene expression and the proliferative response in the presence of arabinan of the probiotic B. longum W11, a strain previously validated as an anti-constipation probiotic, we have speculated that its response mechanism to arabinan can effectively explain its clinical action. Our approach could be used in the future to select probiotics endowed with arabinofuranosidase-related anti-constipation effects.

The Efficacy of Probiotics, Prebiotics, Synbiotics, and Fecal Microbiota Transplantation in Irritable Bowel Syndrome: A Systematic Review and Network Meta-Analysis

Irritable bowel syndrome (IBS) is a common gastrointestinal disorder with gut microbiota imbalance playing a significant role. There are increasing numbers of research studies exploring treatment options involving probiotics, prebiotics, synbiotics, and fecal microbiota transplantation (FMT), but it is still uncertain which treatment option is superior. The research was conducted on various databases and unpublished trial data (up to February 2023). Randomized controlled trials (RCTs) were screened for adult patients with IBS comparing interventions with placebo. Probiotics, prebiotics, synbiotics, and FMT were assessed for their impact using mean difference and Bayesian network meta-analysis. Out of 6528 articles, 54 were included for probiotics, 7 for prebiotics/synbiotics, and 6 for FMT. Probiotics showed improvement in IBS symptoms, particularly with Bifidobacterium and Lactobacillus strains. Prebiotics and synbiotics did not show significant improvement. Network meta-analysis indicated the favorable effects of probiotics (OR = 0.53, 95% CI, 0.48 to 0.59) and FMT (OR = 0.46, 95% CI, 0.33 to 0.64) on IBS, with no serious adverse events reported. In short, probiotics and FMT are effective for managing IBS, with Bifidobacterium and Lactobacillus being dominant strains. However, the most effective probiotic combination or strain remains unclear, while prebiotics and synbiotics did not show significant improvement.

Considering traditional Chinese medicine as adjunct therapy in the management of chronic constipation by regulating intestinal flora

Chronic constipation is one of the most common gastrointestinal disorders worldwide. Due to changes in diet, lifestyle, and the aging population, the incidence of chronic constipation has increased year by year. It has had an impact on daily life and poses a considerable economic burden. Nowadays, many patients with chronic constipation try to seek help from complementary and alternative therapies, and traditional Chinese medicine (TCM) is often their choice. The intestinal flora play an important role in the pathogenesis of constipation by affecting the body's metabolism, secretion, and immunity. Regulating the intestinal flora and optimizing its composition might become an important prevention and treatment for chronic constipation. TCM has unique advantages in regulating the imbalance of intestinal flora, and its curative effect is precise. Therefore, we reviewed the relationship between intestinal flora and chronic constipation as well as advances in research on TCM as adjunct therapy in the management of chronic constipation by regulating intestinal flora. Some single Chinese herbs and their active ingredients (e.g., Rheum palmatum, Radix Astragalus, and Cistanche deserticola), some traditional herbal formulations (e.g., Jichuan decoction, Zengye decoction, and Zhizhu decoction) and some Chinese patent medicines (e.g., Maren pills and Shouhui Tongbian capsules) that are commonly used to treat chronic constipation by regulating intestinal flora are highlighted and summarized. Moreover, some external forms of TCM, and especially acupuncture, have also been found to improve intestinal movement and alleviate constipation symptoms by regulating intestinal flora. We hope this review can contribute to an understanding of TCM as an adjunct therapy for chronic constipation and that it can provide useful information for the development of more effective constipation therapies.

Functional Constipation and Obstructed Defecation

Constipation encompasses symptoms of decreased colonic motility or difficulty with the defecation process. As a broad definition, this can be inclusive of functional constipation (FC) or colonic inertia, obstructed defecation (OD), and irritable bowel syndrome-constipation type (IBS-CS). After excluding IBS-C, FC and OD diagnosis and management require a multidisciplinary approach often involving nutritionists, pelvic floor therapists, urogynecologists, and colon and rectal surgeons. Differentiating the presence or absence of each can direct therapy and prognosticate chances for improvement in this often complex combination of disorders.

Microbiota treatment of functional constipation: Current status and future prospects

Functional constipation (FC) is a common disorder that is characterized by difficult stool passage, infrequent bowel movement, or both. FC is highly prevalent, recurs often, accompanies severe diseases, and affects quality of life; therefore, safe and effective therapy with long-term benefits is urgently needed. Microbiota treatment has potential value for FC treatment. Microbiota treatments include modulators such as probiotics, prebiotics, synbiotics, postbiotics, and fecal microbiota transplantation (FMT). Some probiotics and prebiotics have been adopted, and the efficacy of other microbiota modulators is being explored. FMT is considered an emerging field because of its curative effects; nevertheless, substantial work must be performed before clinical implementation.

Effect of Probiotics in Stress-Associated Constipation Model in Zebrafish (Danio rerio) Larvae

The pathophysiology of functional bowel disorders is complex, involving disruptions in gut motility, visceral hypersensitivity, gut-brain-microbiota interactions, and psychosocial factors. Light pollution, as an environmental stressor, has been associated with disruptions in circadian rhythms and the aggravation of stress-related conditions. In this study, we investigated the effects of environmental stress, particularly continuous light exposure, on intestinal motility and inflammation using zebrafish larvae as a model system. We also evaluated the efficacy of probiotics, specifically Bifidobacterium longum (B. longum), at alleviating stress-induced constipation. Our results showed that continuous light exposure in zebrafish larvae increased the cortisol levels and reduced the intestinal motility, establishing a stress-induced-constipation model. We observed increased inflammatory markers and decreased intestinal neural activity in response to stress. Furthermore, the expressions of aquaporins and vasoactive intestinal peptide, crucial for regulating water transport and intestinal motility, were altered in the light-induced constipation model. Administration of probiotics, specifically B. longum, ameliorated the stress-induced constipation by reducing the cortisol levels, modulating the intestinal inflammation, and restoring the intestinal motility and neural activity. These findings highlight the potential of probiotics to modulate the gut-brain axis and alleviate stress-induced constipation. Therefore, this study provides a valuable understanding of the complex interplay among environmental stressors, gut function, and potential therapeutic strategies.

Prebiotics and Probiotics for Gastrointestinal Disorders

The complex role of the gut microbiome in the pathogenesis of gastrointestinal (GI) disorders is an emerging area of research, and there is considerable interest in understanding how diet can alter the composition and function of the microbiome. Prebiotics and probiotics have been shown to beneficially modulate the gut microbiome, which underlies their potential for benefit in GI conditions. Formulating specific recommendations for the public regarding these dietary supplements has been difficult due to the significant heterogeneity between strains, doses, and duration of treatment investigated across studies, as well as safety concerns with administering live organisms. This review aims to summarize the existing evidence for the use of prebiotics and probiotics in various GI disorders, paying special attention to strain-specific effects that emerged and any adverse effects noted.

Association between Dietary Intake of Live Microbes and Chronic Constipation in Adults

BACKGROUND

Chronic constipation (CC) is a common gut health problem, and the role of live dietary microbes in CC is unclear.

OBJECTIVE

This study aimed to investigate the relationship between dietary live microbes consumption and CC.

METHODS

Using the National Health and Nutrition Examination Survey data (2005-2010), 11,170 adults who completed the 24-h face-to-face dietary recall and bowel health questionnaire were identified. CC was defined by the Bristol Stool Form Scale. Dietary live microbes intake was classified as low, medium, and high. Additionally, combined medium and high categories (MedHi) were analyzed. Multivariate regression models were constructed to assess the association between dietary intake of live microbes and CC.

RESULTS

In the weighted sample, the age-adjusted CC prevalence was 7.06% (95% confidence interval [CI]: 6.45, 7.67). In multivariate regression models, after controlling for potential confounders race/ethnicity, sex, body mass index, education, poverty, depression, caffeine intake, and alcohol intake, a significant inverse association between dietary live microbes consumption and CC was observed (odds ratio [OR]: 0.77, 95% CI: 0.61, 0.97, P-trend = 0.061).

CONCLUSIONS

Our findings suggest that a high dietary live microbes consumption may be associated with lower odds of CC. However, further prospective studies are essential to confirm its effectiveness in reducing CC occurrence.

Systematic review and meta-analysis: Foods, drinks and diets and their effect on chronic constipation in adults

BACKGROUND

Dietary approaches are recommended for the management of chronic constipation. Until now, there has been no systematic review and meta-analysis on foods, drinks and diets in constipation.

AIMS

To investigate the effect of foods, drinks and diets on response to treatment, stool output, gut transit time, symptoms, quality of life, adverse events and compliance in adults with chronic constipation via a systematic review and meta-analysis.

METHODS

Studies were identified using electronic databases (12th July 2023). Intervention trials (randomised controlled trials [RCTs], non-randomised, uncontrolled) were included. Risk of bias was assessed using Cochrane 2.0 (RCTs) or JBI Critical Appraisal (uncontrolled trials). Data from RCTs only were synthesised using risk ratios (RRs), mean differences (MDs), standardised mean differences (95% CI) using random-effects.

RESULTS

We included 23 studies (17 RCTs, 6 uncontrolled; 1714 participants): kiwifruit (n = 7), high-mineral water (n = 4), prunes (n = 2), rye bread (n = 2), mango, fig, cereal, oat bran, yoghurt, water supplementation, prune juice, high-fibre diet, no-fibre diet (n = 1). Fruits resulted in higher stool frequency than psyllium (MD: +0.36 bowel movements [BM]/week, [0.25-0.48], n = 232), kiwifruits in particular (MD: +0.36 BM/week, [0.24-0.48], n = 192); there was no difference for prunes compared with psyllium. Rye bread resulted in higher stool frequency than white bread (MD: +0.43 BM/week, [0.03-0.83], n = 48). High-mineral water resulted in higher response to treatment than low-mineral water (RR: 1.47, [1.20-1.81], n = 539).

CONCLUSIONS

Fruits and rye bread may improve certain constipation-related outcomes. There is a scarcity of evidence on foods, drinks and diets in constipation and further RCTs are needed.

Probiotics in Functional Gastrointestinal Disorders

The most frequent functional gastrointestinal disorders (FGID) in children include infantile colic, constipation, functional abdominal pain (FAP), and irritable bowel syndrome (IBS). Unfortunately, treatment options for FGID in children are limited, therefore many dietary interventions have been evaluated, including probiotics. This chapter summarizes currently available evidence and recommendations for probiotic use in the treatment of frequent FGIDs in children. The strongest evidence exists for the use of Limosilactobacillus (L.) reuteri DSM 17938 and Bifidobacterium animalis subsp. lactis BB-12 for the treatment of infantile colic in breastfed infants. Limited but yet encouraging evidence exists for Lacticaseibacillus rhamnosus GG (LGG) for the treatment of IBS and L. reuteri DSM 17938 for FAP.

Advice to People with Parkinson's in My Clinic: Probiotics and Prebiotics

There is increasing evidence that microbial-based therapies can be useful in people with Parkinson's disease (PD). In this viewpoint, we provide a state-of-the-art review of the clinical and pre-clinical evidence for probiotics and prebiotics in PD. Currently, short-term clinical studies, including double-blind placebo-controlled randomized clinical trials, have demonstrated safety, and efficacy primarily in improving constipation-related symptoms. Pre-clinical studies consistently reported improvements in a range of biological markers and outcomes, including evidence for attenuation of gut dysfunction and neuroprotection. Bacteria from the genus Lactobacillus and Bifidobacterium have been the most frequently studied both in clinical and pre-clinical probiotics studies, while research into prebiotics is still limited and primarily involved resistant starch and fructooligosaccharides. We provide practical suggestions for clinicians on how to advise patients in the clinic regarding these popular treatments, and important caveats to be aware of. Finally, areas for further advancements are highlighted. It is envisaged that in the future, microbial-based therapies may benefit from personalization based on an enhanced understanding of a whole range of host factors and host-microbiome interactions.

The effect of food, vitamin, or mineral supplements on chronic constipation in adults: A systematic review and meta-analysis of randomized controlled trials

BACKGROUND

Over-the-counter supplements are commonly used to manage chronic constipation; however, their efficacy remains unclear. We aimed to investigate the effect of food, vitamin or mineral supplements on stool output, gut transit time, symptoms, and quality of life in adults with chronic constipation via a systematic review and meta-analysis of randomized controlled trials (RCTs).

METHODS

Studies were identified using electronic databases, backward citation, and hand-searching abstracts. RCTs reporting administration of food supplements (e.g., fruit extract supplements), vitamin or mineral supplements in adults with chronic constipation were included. Studies administering whole foods (e.g., fruits) were excluded. Risk of bias (RoB) was assessed with Cochrane RoB 2.0. Relative risks (RR), mean differences (MD), or standardized mean differences (95% confidence intervals [CI]) were calculated using a random-effects model.

KEY RESULTS

Eight RCTs (787 participants) were included, investigating kiwifruit (n = 3 RCTs), senna (n = 2), magnesium oxide (n = 2), Ziziphus jujuba (n = 1), and Malva Sylvestris (n = 1) supplements. Kiwifruit supplements did not impact stool frequency (MD 0.24 bowel movements/week [-0.32, 0.80]; p = 0.40) or consistency (MD -0.11 Bristol points [-0.31, 0.09], p = 0.29). Overall, 61% responded to senna and 28% to control; however, this did not reach statistical significance (RR 2.78, [0.93, 8.27]; p = 0.07). Overall, 68% responded to magnesium oxide and 19% to control (RR 3.32 [1.59, 6.92]; p = 0.001). Magnesium oxide improved stool frequency (MD 3.72 bowel movements/week [1.41, 6.03]; p = 0.002) and consistency (MD 1.14 Bristol points [0.48, 1.79]; p = 0.0007).

CONCLUSIONS AND INFERENCES

Magnesium oxide supplements are effective at improving cardinal symptoms of chronic constipation. Senna and kiwifruit supplements did not impact symptoms; however, findings were based on a small number of studies. Further research is required to investigate the effect of food supplements (e.g., kiwifruit supplements), as well as their whole food equivalents (e.g., whole kiwifruits) in chronic constipation.

The Efficacy and Safety of Single-Strain Probiotic Formulations Containing Bifidobacterium lactis or Bacillus coagulans in Adult Patients with Irritable Bowel Syndrome-A Randomized Double-Blind Placebo-Controlled Three-Arm Interventional Trial

Probiotics offer a potential new therapeutic approach for irritable bowel syndrome (IBS), but current results are still controversial. The aim of this study was to assess the efficacy and safety of single-strain probiotic formulations in adult IBS patients and to compare the effects of Bifidobacterium lactis NORDBIOTIC™ BI040 (DSM 33812/34614) and Bacillus coagulans NORDBIOTIC™ BC300 (DSM 33836) in a prospective three-arm interventional randomized double-blind placebo-controlled clinical trial. The study included 123 IBS subjects diagnosed according to the Rome IV criteria. The primary outcomes were changes in symptom severity and symptom improvement as assessed using the IBS Severity Scoring System (IBS-SSS) after 4, 8, and 12 weeks of intervention and after 4 weeks of follow-up. Secondary outcomes included the assessment of individual IBS symptoms and the occurrence of adverse events. During the 12-week intervention, IBS-SSS scores significantly decreased (p-values < 0.001) in the study groups but differences between the interventional and placebo groups did not reach statistical significance. However, at the 16th week of follow-up, a significant improvement in the total IBS-SSS score in comparison to the placebo group (20.5%) was found in 43.8% and 52.9% of the Bifidobacterium lactis (p = 0.038, OR 3.0, [95% CI 1.1-8.6]) and the Bacillus coagulans (p = 0.005, OR 4.6 [95% CI 1.5-12.2]) groups, respectively. Bifidobacterium lactis had a beneficial effect on the intensity and frequency of pain, whereas Bacillus coagulans decreased the bowel dissatisfaction. Both strains increased the percentage of patients with normal stool consistency, but only Bifidobacterium lactis induced a decrease in the number of patients with constipation after 6 weeks of supplementation. Both probiotic strains were well tolerated, without differences in the occurrence of adverse events between groups. In conclusion, single-strain supplementation was safe and efficient in IBS patients but showed a different range of effects. Bifidobacterium lactis BI040 primarily reduced the frequency and intensity of pain, while Bacillus coagulans BC300 increased bowel satisfaction [ClinicalTrials.gov NCT05064930].

American Gastroenterological Association-American College of Gastroenterology Clinical Practice Guideline: Pharmacological Management of Chronic Idiopathic Constipation

INTRODUCTION

Chronic idiopathic constipation (CIC) is a common disorder associated with significant impairment in quality of life. This clinical practice guideline, jointly developed by the American Gastroenterological Association and the American College of Gastroenterology, aims to inform clinicians and patients by providing evidence-based practice recommendations for the pharmacological treatment of CIC in adults.

METHODS

The American Gastroenterological Association and the American College of Gastroenterology formed a multidisciplinary guideline panel that conducted systematic reviews of the following agents: fiber, osmotic laxatives (polyethylene glycol, magnesium oxide, lactulose), stimulant laxatives (bisacodyl, sodium picosulfate, senna), secretagogues (lubiprostone, linaclotide, plecanatide), and serotonin type 4 agonist (prucalopride). The panel prioritized clinical questions and outcomes and used the Grading of Recommendations Assessment, Development, and Evaluation framework to assess the certainty of evidence for each intervention. The Evidence to Decision framework was used to develop clinical recommendations based on the balance between the desirable and undesirable effects, patient values, costs, and health equity considerations.

RESULTS

The panel agreed on 10 recommendations for the pharmacological management of CIC in adults. Based on available evidence, the panel made strong recommendations for the use of polyethylene glycol, sodium picosulfate, linaclotide, plecanatide, and prucalopride for CIC in adults. Conditional recommendations were made for the use of fiber, lactulose, senna, magnesium oxide, and lubiprostone.

DISCUSSION

This document provides a comprehensive outline of the various over-the-counter and prescription pharmacological agents available for the treatment of CIC. The guidelines are meant to provide a framework for approaching the management of CIC; clinical providers should engage in shared decision making based on patient preferences as well as medication cost and availability. Limitations and gaps in the evidence are highlighted to help guide future research opportunities and enhance the care of patients with chronic constipation.

American Gastroenterological Association-American College of Gastroenterology Clinical Practice Guideline: Pharmacological Management of Chronic Idiopathic Constipation

INTRODUCTION

Chronic idiopathic constipation (CIC) is a common disorder associated with significant impairment in quality of life. This clinical practice guideline, jointly developed by the American Gastroenterological Association and the American College of Gastroenterology, aims to inform clinicians and patients by providing evidence-based practice recommendations for the pharmacological treatment of CIC in adults.

METHODS

The American Gastroenterological Association and the American College of Gastroenterology formed a multidisciplinary guideline panel that conducted systematic reviews of the following agents: fiber, osmotic laxatives (polyethylene glycol, magnesium oxide, lactulose), stimulant laxatives (bisacodyl, sodium picosulfate, senna), secretagogues (lubiprostone, linaclotide, plecanatide), and serotonin type 4 agonist (prucalopride). The panel prioritized clinical questions and outcomes and used the Grading of Recommendations Assessment, Development, and Evaluation framework to assess the certainty of evidence for each intervention. The Evidence to Decision framework was used to develop clinical recommendations based on the balance between the desirable and undesirable effects, patient values, costs, and health equity considerations.

RESULTS

The panel agreed on 10 recommendations for the pharmacological management of CIC in adults. Based on available evidence, the panel made strong recommendations for the use of polyethylene glycol, sodium picosulfate, linaclotide, plecanatide, and prucalopride for CIC in adults. Conditional recommendations were made for the use of fiber, lactulose, senna, magnesium oxide, and lubiprostone.

DISCUSSION

This document provides a comprehensive outline of the various over-the-counter and prescription pharmacological agents available for the treatment of CIC. The guidelines are meant to provide a framework for approaching the management of CIC; clinical providers should engage in shared decision making based on patient preferences as well as medication cost and availability. Limitations and gaps in the evidence are highlighted to help guide future research opportunities and enhance the care of patients with chronic constipation.

Efficacy and Safety of Probiotics in Geriatric Patients with Constipation: Systematic Review and Meta-Analysis

BACKGROUND

Probiotics may be an effective alternative to traditional drug therapy for constipation in the elderly.

OBJECTIVE

To assess the efficacy and safety of probiotics in managing constipation among the elderly.

METHODS

Eight databases were queried for randomized controlled trials (RCTs) investigating probiotics' efficacy in addressing constipation among the elderly until January 2023. The meta-analysis was conducted employing R software version 4.2.2. The Cochrane risk of bias tool was utilized to evaluate the risk of bias, and the GRADE approach was employed to assess the credibility of the evidence concerning the efficacy of probiotics in treating constipation in older individuals.

RESULTS

A total of six RCTs involving 444 patients were included. Two studies were rated as low risk of bias. The meta-analysis findings revealed that probiotics, when compared to a placebo, led to an increase in stool frequency (MD = 1.02,95% CI [0.21, 2.07], p<0.05, very low quality), the probiotic group exhibited a notable impact on ameliorating symptoms associated with constipation (OR = 11.28, 95%CI [7.21, 17.64], p < 0.05, very low quality), no significant disparities were observed in terms of efforts to evacuate, manual maneuvers, and the incidence of adverse events (p>0.05).

CONCLUSION

The available evidence indicates a degree of uncertainty, ranging from low-to-very low, suggesting the efficacy of probiotics in augmenting bowel frequency and ameliorating constipation-related symptoms among elderly patients with constipation. Nevertheless, given the quality of the studies included, it is advisable to conduct further well-designed investigations with substantial sample sizes to substantiate the findings of this study.