Probiotic use is common in constipation, but only a minority of general and specialist doctors recommend them and consider there to be an evidence base

Lactic acid bacteria in relieving constipation: mechanism, clinical application, challenge, and opportunity

Constipation is a prevalent gastrointestinal symptom that can considerably affect a patients' quality of life. Although several drugs have been used to treat constipation, they are associated with high costs, side effects, and low universality. Therefore, alternative intervention strategies are urgently needed. Traditional lactic acid bacteria (LAB), such as Bifidobacterium and Lactobacillus, play a vital role in regulating intestinal microecology and have demonstrated favorable effects in constipation; however, a comprehensive review of their constipation relief mechanisms is limited. This review summarizes the pathogenesis of constipation and the relationship between intestinal motility and gut microbiota, elucidates the possible mechanism by which LAB alleviates of constipation through a systematic summary of animal and clinical research, and highlights the challenges and applications of LAB in the treatment of constipation. Our review can improve our understanding of constipation, and advance targeted microecological therapeutic agents, such as LAB.

Impact of Probiotics on the Prevention and Treatment of Gastrointestinal Diseases in the Pediatric Population

Despite the high prevalence of gastrointestinal disorders (GIDs) in infants and children, especially those categorized as functional GIDs (FGIDs), insufficient knowledge about their pathophysiology has limited both symptomatic diagnosis and the development of optimal therapies. Recent advances in the field of probiotics have made their potential use as an interesting therapeutic and preventive strategy against these disorders possible, but further efforts are still needed. In fact, there is great controversy surrounding this topic, generated by the high variety of potential probiotics strains with plausible therapeutic utility, the lack of consensus in their use as well as the few comparative studies available on probiotics that record their efficacy. Taking into account these limitations, and in the absence of clear guidelines about the dose and timeframe for successful probiotic therapy, our review aimed to evaluate current studies on potential use of probiotics for the prevention and treatment of the most common FGIDs and GIDs in the pediatric population. Furthermore, matters referring to know major action pathways and key safety recommendations for probiotic administration proposed by major pediatric health agencies shall also be discussed.

Integrated 16S rDNA sequencing and metabolomics to explore the intestinal changes in children and rats with dental fluorosis

Dental fluorosis (DF) is a widely prevalent disease caused by excessive fluoride with limited awareness of its underlying pathogenesis. Here, a pilot population study was conducted to explore the pathogenesis of DF from the perspective of intestinal microbiome changes, and verified it in animal experiments combining intestinal microbiome and metabolomics. A total of 23 children were recruited in 2017 in China and divided into DF (n = 9) and control (n = 14) groups (DFG and CG, respectively). The SD rat model was established by drinking water containing sodium fluoride (NaF). Gut microbiome profiles of children and rats were analyzed by16S rDNA V3-V4 sequencing, and the intestinal metabolomics analysis of rats was performed by LC-MS methods. The 16 S rDNA sequencing revealed that the gut microbiome composition was significantly perturbed in children in DFG compared to that in CG. Acidobacteria and Thermi were specifically observed in DFG and CG, respectively. Besides, 15 fecal microbiotas were significantly altered at the genus level in DFG. Furthermore, only the expression of annotated genes for pentose and glucuronate interconversion pathway was significant lower in DFG than that in CG (P = 0.04). Notably, in NaF-treated rats, we also observed the changes of some key components of pentose and glucuronate interconversion pathway at the level of microorganisms and metabolites. Our findings suggested that the occurrence of DF is closely related to the alteration of intestinal microorganisms and metabolites annotated in the pentose and glucuronate interconversion pathway.

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

BACKGROUND & AIMS

Probiotics and synbiotics have been increasingly investigated for the management of chronic constipation. We aimed to investigate the effect of probiotics and synbiotics 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. The search date was 10 July 2022. RCTs reporting administration of probiotics or synbiotics in adults with chronic constipation were included. Risk of bias (RoB) was assessed with the Cochrane RoB 2.0 tool. Meta-analysis was conducted separately for probiotics and synbiotics. Results were synthesized using risk ratios (RRs), mean differences or standardized mean differences (SMDs) and 95% confidence intervals (CIs) using a random-effects model.

RESULTS

Thirty RCTs investigating probiotics and four RCTs investigating synbiotics were included. Overall, 369/647 (57%) responded to probiotic treatment and 252/567 (44%) to control (RR 1.28, 95% CI 1.07, 1.52, p = 0.007). Probiotics increased stool frequency (SMD 0.71, 95% CI 0.37, 1.04, p < 0.00001), with Bifidobacterium lactis having a significant effect, but not mixtures of probiotics, Bacillus coagulans Unique IS2 or Lactobacillus casei Shirota. Probiotics did not impact stool consistency (SMD 0.26, 95% CI -0.03, 0.54, p = 0.08). Probiotics improved integrative symptom scores compared to control (SMD -0.46, 95% CI -0.89, -0.04). Synbiotics did not impact stool output or integrative symptom scores compared to control.

CONCLUSIONS

Certain probiotics may improve response to treatment, stool frequency and integrative constipation symptoms, providing cautious optimism for their use as a dietary management option. There is currently insufficient evidence to recommend synbiotics in the management of chronic constipation. Caution is needed when interpreting these results due to high heterogeneity and risk of bias amongst the studies.

Online information in Spanish on probiotics, yoghurt, kefir, kombucha, fibre and prebiotics: an analysis of the quality of information and the certainty of the evidence supporting health claims

OBJECTIVE

To examine the certainty of the evidence supporting health claims about probiotics, yoghurt, kefir, kombucha, fibre and prebiotics, and to assess the quality of online information in Spanish.

DESIGN

Content analysis.

METHODS

We compiled a data set of 114 web pages by searching six popular search phrases in Spanish relating to probiotics, yoghurt, kefir, kombucha, fibre and prebiotics on Google.es and coded them for typology and health claims. We examined the certainty of the evidence for health claims from systematic reviews. Information quality was assessed according to 10 criteria, where a web page: mentions scientific publications and reports their conclusions; quantifies relative and absolute effects; acknowledges some limitations; discusses certainty of evidence; reports the potential harms, alternatives and costs; and does not argue based on personal experiences.

RESULTS

Gastrointestinal health (86.0%), general health (57.9%), cardiovascular health (53.5%) and immune system health (50.9%) were the most widely mentioned topics. Half of claims (52.6%, 70/133) were supported by evidence from systematic reviews. Probiotics had the highest number of claims supported by evidence and kombucha the lowest. The highest certainty was found for antibiotic-associated diarrhoea, necrotising enterocolitis and otitis (moderate) in probiotics and yoghurt, infectious diarrhoea and hepatic encephalopathy (moderate) in prebiotics, and cardiovascular health (high to moderate) and colorectal cancer (moderate) in fibre. On a scale of 0-10, the median information quality score for all web pages was 3. Only 18.4% reported study conclusions, 7.9% quantified the effects, 28.9% acknowledged some limitations in the research and 42.1% reported potential harms.

CONCLUSIONS

Most online health claims for dietary interventions intended for improving health through the gut microbiome are supported by low or very low certainty of evidence. Online information does not align with the evidence and is incomplete or unbalanced.

Who uses probiotics and why? A survey study conducted among general gastroenterology patients

Background

The rapid growth of the probiotic industry suggests patients will continue to seek advice from gastroenterologists about probiotics. To best address patient questions and concerns, we must first understand who uses probiotics and why.

Methods

This was a cross-sectional study conducted in the endoscopy suite of an academic hospital from June to October of 2019. Surveys were anonymous and contained a combination of multiple choice, free text and Likert scale questions. Participants privately completed a paper survey in English or Spanish and the results were reviewed with them by study personnel to clarify responses. Descriptive statistics were generated and multivariable logistic regression modelling was used to compare characteristics of probiotic users versus non-users.

Results

During the 5-month study period, 600 patients were approached and 537 (90%) agreed to participate. Among participants, 89% completed at least 24 survey items and were included in the analysis. Overall, 27% of patients reported probiotic use. Bloating, rather than diarrhoea, was the main gastrointestinal symptom associated with use of probiotics (aOR 2.59, 95% CI 1.52 to 4.44 for bloating; aOR 1.03, 95% CI 0.55 to 1.94 for diarrhoea). Frequent reasons cited for taking probiotics were the beliefs that they improved overall health and longevity (54%) and that they improved gastrointestinal symptoms (45%).

Conclusions

Probiotic use is common among general gastroenterology patients, many of whom believe that probiotics confer general rather than specific gastrointestinal health benefits. Symptoms—especially bloating—and not sociodemographic factors seem to motivate probiotic use. By understanding patient expectations for probiotics, clinicians can better advise them.

Constipation might be associated with risk of allergic rhinitis: A nationwide population-based cohort study

Background

Allergic rhinitis (AR) is a burdensome respiratory disorder whose etiology and pathophysiology remain controversial and most likely multifactorial. Accumulated evidence indicates that gut dysbiosis contributes to AR via the gut-airway axis. Constipation could result in alteration of the intestinal microflora. The clinical impact of constipation on AR has not been studied. We aimed to evaluate the risk of AR in constipated patients using a nationwide longitudinal population-based cohort.

Methods

We identified 57786 patients with constipation and 57786 matched controls between 1999 and 2013 from the Longitudinal Health Insurance Database, which is a subset of Taiwanese National Health Insurance Research Database. Propensity score analysis was used for matching age, sex, comorbidities, and medications at a ratio of 1:1. Multiple Cox regression and subgroup analyses were used to estimate the adjusted hazard ratio of AR.

Results

The incidence of AR was 32.2 per 1,000 person-years in constipated patients, which was twice that of non-constipated patients. After adjustment for patients’ age, gender, comorbidities, and medications, patients with constipation had a 2.3-fold risk of AR compared to those without constipation (adjusted hazard ratio [aHR]: 2.30; 95% CI, 2.23–2.37). In subgroup analyses, patients aged 20–39 years had a 2.24-fold higher risk of AR in the constipation cohort (aHR; 95% CI, 2.12–2.36). Patients aged <20, 40–64, and ≥65 years had a 2.09, 2.05, and 2.07-fold risk of AR in the constipation cohort, respectively (aHR; 95% CI, 1.98–2.20, 1.94–2.18, and 1.92–2.23). Also, patients with constipation had a higher likelihood of AR, regardless of sex, and with or without comorbidities including hyperlipidemia, hypertension, chronic kidney disease, chronic liver disease, diabetes, chronic obstructive pulmonary disease, rheumatoid arthritis, dyspepsia, irritable bowel syndrome, and anxiety.

Conclusion

Constipation might be associated with an increased risk of incidental AR. It seems that physicians should keep a higher index of suspicion for AR in people with constipation. The patency issue of gut could not be ignored in patients with AR.

Are probiotics useful in the treatment of chronic idiopathic constipation in adults? A review of existing systematic reviews, meta-analyses, and recommendations

Chronic idiopathic constipation (CIC) has emerged as common problem for contemporary gastroenterology and is one of the most frequent complaints in primary care. Chronic idiopathic constipation significantly affects patients' quality of life and has an impact on global health and economy. Functional gastrointestinal disorders and bowel disorders, according to Rome IV criteria, result from inappropriate gut-brain interactions. The pathophysiology is complex and poorly understood, with evidence accumulating that gut microbiota can be implicated in the development and function of the enteric nervous system. Gut bacteria modulate gut barrier function, short chain fatty acid synthesis, and bile acid metabolism, factors which play roles in the gut peristalsis regulation. The high prevalence of CIC, with poor treatment outcomes, warrants searches for new forms of therapy, including probiotic therapies. Probiotics are often recommended by medical practitioners, but evidence-based utility in adults with CIC is uncertain. Recommendations/guidelines are often based on results from individual studies, rather than meta-analyses or umbrella reviews. Additionally, meta-analyses often indicate a group of probiotics rather than individual strains, and they create difficulty for physicians in making therapeutic choices. More CIC patient randomised clinical studies utilising well-defined strains, or combinations, are necessary.

Probiotics and constipation: mechanisms of action, evidence for effectiveness and utilisation by patients and healthcare professionals

The aim of this narrative review is to assess and present evidence on the mechanisms of action of probiotics in constipation, their effectiveness and their utilisation by patients and healthcare professionals. Chronic constipation is a common bothersome disorder that has a considerable impact on patients' quality of life. Probiotics have been increasingly investigated for their effectiveness in various disorders, including chronic constipation. Probiotics may affect gut motility and constipation through their impact on the gut microbiota and fermentation, the central and enteric nervous system and the immune system. However, evidence for the effectiveness of probiotics in the management of constipation remains varied, with some strains demonstrating improvements, while others show no effect. Despite the uncertainty in evidence and the fact that the majority of healthcare professionals do not recommend probiotics for constipation, an increased prevalence of probiotic use by people with constipation has been shown. Therefore, there is a need for public health strategies to inform the public about where strong evidence of probiotic effectiveness exist, and where evidence is still weak. Education of healthcare professionals on the increased utilisation of probiotics for constipation by the public and on current evidence for the effectiveness of specific strains is also required.