Worldwide Prevalence and Burden of Functional Gastrointestinal Disorders, Results of Rome Foundation Global Study

Gastrointestinal Biofilms: Endoscopic Detection, Disease Relevance, and Therapeutic Strategies

Gastrointestinal biofilms are matrix-enclosed, highly heterogenic and spatially organized polymicrobial communities that can cover large areas in the gastrointestinal tract. Gut microbiota dysbiosis, mucus disruption, and epithelial invasion are associated with pathogenic biofilms that have been linked to gastrointestinal disorders such as irritable bowel syndrome, inflammatory bowel diseases, gastric cancer, and colorectal cancer. Intestinal biofilms are highly prevalent in ulcerative colitis and irritable bowel syndrome patients, and most endoscopists will have observed such biofilms during colonoscopy, maybe without appreciating their biological and clinical importance. Gut biofilms have a protective extracellular matrix that renders them challenging to treat, and effective therapies are yet to be developed. This review covers gastrointestinal biofilm formation, growth, appearance and detection, biofilm architecture and signalling, human host defence mechanisms, disease and clinical relevance of biofilms, therapeutic approaches, and future perspectives. Critical knowledge gaps and open research questions regarding the biofilm's exact pathophysiological relevance and key hurdles in translating therapeutic advances into the clinic are discussed. Taken together, this review summarizes the status quo in gut biofilm research and provides perspectives and guidance for future research and therapeutic strategies.

Burden of illness and treatment attitudes among participants meeting Rome IV criteria for irritable bowel syndrome: A nationwide survey in the United States

BACKGROUND

Irritable bowel syndrome (IBS) is a disorder of gut-brain interaction characterized by abdominal pain and altered bowel habits, with patient-perceived dissatisfaction of treatment symptom control. We assessed disease burden, satisfaction with medication use, and impact on activities, in participants with IBS with constipation (IBS-C) and diarrhea (IBS-D).

METHODS

This study assessed data from a large, United States survey of adults querying demographics, comorbid conditions, quality of life, medication use, satisfaction with symptom control, and work productivity. Participants were grouped into the IBS-C or IBS-D cohort if they met Rome IV criteria, with controls matched 1:1 according to age, sex, race, region, and Charlson Comorbidity Index score. All data were self-reported.

KEY RESULTS

Nine hundred and ten participants with IBS-C and 669 with IBS-D were matched to controls. The most reported symptoms were abdominal discomfort for IBS-C and abdominal pain and abdominal discomfort for IBS-D. Among the IBS-C and IBS-D cohorts, 74.2% and 65.9%, respectively, took prescription and/or over-the-counter medication for their symptoms. Respondents were more dissatisfied than satisfied with control of their symptoms. Respondents taking prescription medication(s) with or without over-the-counter medication(s) reported better symptom control than respondents only taking over-the-counter medications (p < 0.001). There was significantly higher mean presenteeism, work productivity loss, and daily activity impairment (p < 0.001 for all) in respondents with IBS compared with controls.

CONCLUSIONS AND INFERENCES

This study provides insight into respondents' experiences of IBS symptoms, including the impact on daily activity, as well as satisfaction with control of symptoms and prescription and over-the-counter medications.

Serum Exosomal MicroRNAs as Potential Biomarkers for Centrally Mediated Abdominal Pain Syndrome

Centrally mediated abdominal pain syndrome (CAPS) has generated a heavy disease burden worldwide. This study aimed to explore the serum exosomal microRNAs (miRNAs) as potential diagnostic biomarkers for CAPS. From September 2022 to October 2023, 97 patients with CAPS and 96 healthy subjects were enrolled. Differentially expressed serum exosomal miRNAs between patients with CAPS and healthy controls were identified by high-throughput sequencing and quantitative real-time polymerase chain reaction. The receiver operating characteristic curves and multivariate logistic regression analysis were used to evaluate the diagnostic value of the serum exosomal miRNAs. MiR-6850-5p, miR-194-5p, miR-199a-3p, and miR-4525 were significantly downregulated in serum exomes of CAPS patients compared with healthy controls, which yielded the area under curve (AUC) values of .914 (95% confidence interval (CI), .873-.954), .767 (95% CI, .695-.839), .617 (95% CI, .527-.708), and .561 (95% CI, .465-.656), respectively, to distinguish CAPS patients from healthy subjects. And AUC of the integration of the above 4 miRNAs was .931 (95% CI, .896-.966). Multivariate logistic regression indicated that hsa-miR-6850-5p (odds ratio (OR) = .046, P < .001), anxiety (OR = 7.670, P = .025), and depression (OR = 22.967, P = .008) were the independent predictors of CAPS. Serum exosomal miR-6850-5p is a promising diagnostic biomarker for CAPS. PERSPECTIVE: This study may be the first to explore serum exosomal miRNAs as new diagnostic biomarkers for CAPS, and the findings may help clinicians to access comprehensive understanding and accurate diagnosis of CAPS.

Dectin-1 induces TRPV1 sensitization and contributes to visceral hypersensitivity of irritable bowel syndrome in male mice

BACKGROUND

Visceral hypersensitivity is considered the core pathophysiological mechanism that causes abdominal pain in patients with irritable bowel syndrome (IBS). Fungal dysbiosis has been proved to contribute to visceral hypersensitivity in IBS patients. However, the underlying mechanisms for Dectin-1, a major fungal recognition receptor, in visceral hypersensitivity are poorly understood. This study aimed to explore the role of Dectin-1 in visceral hypersensitivity and elucidate the impact of Dectin-1 activity on the function of transient receptor potential vanilloid type 1 (TRPV1).

METHODS

Visceral hypersensitivity model was established by the intracolonic administration of 0.1 mL TNBS (130 μg/mL in 30% ethanol) in the male mice. Fluconazole and nystatin were used as fungicides. Laminarin, a Dectin-1 antagonist and gene knockout (Clec7a-/-) mice were used to interrupt the function of Dectin-1. Colorectal distension-electromyogram recording was performed to assess visceral sensitivity. Immunostaining experiment was performed to determine the localization of Dectin-1 in dorsal root ganglion (DRG) neurons. Calcium imaging study was performed to assay TRPV1-mediated calcium influx in acutely dissociated DRG neurons.

RESULTS

Pretreatment with fungicides, administration of laminarin or genetic deletion of Clec7a alleviated TNBS-induced visceral hypersensitivity in male mice. The expression of Dectin-1 was upregulated in the DRG and colon of TNBS-treated mice. Colocalization of Dectin-1 and TRPV1 was observed in DRG neurons. Importantly, pretreatment with curdlan, a Dectin-1 agonist, increased TRPV1-mediated calcium influx.

CONCLUSIONS

Dectin-1 contributes to visceral hypersensitivity in IBS or in inflammatory bowel disease in remission and activation of Dectin-1 induces TRPV1 sensitization.

SIGNIFICANCE STATEMENT

This work provides direct evidence for the functional regulation of TRPV1 channel by Dectin-1 activity, proposing a new mechanism underlying TRPV1 sensitization. Control of intestinal fungi might be beneficial for the treatment of refractory abdominal pain in patients with IBS or IBD in remission.

Molecular Mechanisms Underlying Loss of Vascular and Epithelial Integrity in Irritable Bowel Syndrome

BACKGROUND & AIMS

The pathophysiology of irritable bowel syndrome (IBS) is multifactorial and includes epithelial barrier dysfunction, a key element at the interface between the gut lumen and the deeper intestinal layers. Beneath the epithelial barrier there is the vascular one representing the last barrier to avoid luminal antigen dissemination The aims of this study were to correlate morpho-functional aspects of epithelial and vascular barriers with symptom perception in IBS.

METHODS

Seventy-eight healthy subjects (controls) and 223 patients with IBS were enrolled in the study and phenotyped according to validated questionnaires. Sugar test was used to evaluate in vivo permeability. Immunohistochemistry, western blot, and electron microscopy were used to characterize the vascular barrier. Vascular permeability was evaluated by assessing the mucosal expression of plasmalemma vesicle-associated protein-1 and vascular endothelial cadherin. Caco-2 or human umbilical vein endothelial cell monolayers were incubated with soluble mediators released by mucosal biopsies to highlight the mechanisms involved in permeability alteration. Correlation analyses have been performed among experimental and clinical data.

RESULTS

The intestinal epithelial barrier was compromised in patients with IBS throughout the gastrointestinal tract. IBS-soluble mediators increased Caco-2 permeability via a downregulation of tight junction gene expression. Blood vessel density and vascular permeability were increased in the IBS colonic mucosa. IBS mucosal mediators increased permeability in human umbilical vein endothelial cell monolayers through the activation of protease-activated receptor-2 and histone deacetylase 11, resulting in vascular endothelial cadherin downregulation. Permeability changes correlated with intestinal and behavioral symptoms and health-related quality of life of patients with IBS.

CONCLUSIONS

Epithelial and vascular barriers are compromised in patients with IBS and contribute to clinical manifestations.

Disorders of gastric motility

Gastroparesis is a disorder of delayed gastric emptying with associated symptoms of postprandial fullness, early satiety, nausea, vomiting, bloating, and abdominal pain. Functional dyspepsia is an upper gastrointestinal disorder of gut-brain interaction that presents with similar symptoms but is defined according to symptom patterns rather than gastric motor dysfunction. Although delayed gastric emptying is a defining feature of gastroparesis, other aspects of gastric neuromuscular dysfunction, such as gastric accommodation and visceral hypersensitivity might contribute to symptoms. Similarly, although functional dyspepsia is not defined by impaired gastric emptying, disordered gastric motility might underlie pathogenesis in some patients with functional dyspepsia. In the last decade, it has been increasingly recognised that these two disorders might represent varying presentations along a common continuum of neuromuscular dysfunction, although with differentiating features with respect to outcomes, diagnosis, and treatments. In this Review, an overview of gastroparesis and functional dyspepsia from the perspective of gastric motility is provided, discussing what is distinct and what is shared between these disorders.

Bidirectional association between type 2 diabetes and irritable bowel syndrome: A large-scale prospective cohort study

AIM

To examine the bidirectional association between type 2 diabetes (T2D) and irritable bowel syndrome (IBS) in a large prospective population cohort.

METHODS

Participants free of IBS at baseline in the UK Biobank were included in the analysis of T2D and incident IBS (cohort 1), with 11 140 T2D patients and 413 979 non-T2D patients. Similarly, those free of T2D at baseline were included in the analysis of IBS and incident T2D (cohort 2), with 21 944 IBS patients and 413 979 non-IBS patients. Diagnoses of T2D and IBS were based on International Classification of Disease-10 codes. The Cox proportional hazards model was used to estimate adjusted hazard ratios (HRs).

RESULTS

In cohort 1, 8984 IBS cases were identified during a median 14.5-year follow-up. Compared with non-T2D, T2D patients had a 39.0% increased risk of incident IBS (HR = 1.39, 95% confidence interval [CI]: 1.23-1.56, P < .001), with a higher IBS risk in those with higher fasting blood glucose levels (HR = 1.43, 95% CI: 1.19-1.72, P < .001) or longer T2D duration (HR = 1.47, 95% CI: 1.23-1.74, P < .001). In cohort 2, 29 563 incident T2D cases were identified. IBS patients had an 18.0% higher risk of developing T2D versus non-IBS patients (HR = 1.18, 95% CI: 1.12-1.24, P < .001). A similar excess T2D risk was observed in IBS patients with a duration of either less than 10 years, or of 10 years or longer. Further sensitivity analysis and subgroup analysis indicated consistent findings.

CONCLUSIONS

T2D and IBS exhibit a bidirectional association, with an increased risk of co-morbidity. Awareness of this association may improve the prevention and management of both diseases.

Uncovering the material basis and mechanism of Jianwei Xiaoshi tablet against functional dyspepsia using ultra-high-performance liquid chromatography-mass spectrometry and network pharmacology

Functional dyspepsia (FD) is a common digestive disease. Jianwei Xiaoshi (JWXS) tablet is composed of Radix Pseudostellariae (TZS), Pericarpium Citri Reticulatae (CP), Rhizoma Dioscoreae (SY), fired Hordei Fructus Germinatus (CMY) and Crataegi Fructus (SZ). It is a commonly used drug in the treatment of FD in China and has good therapeutic effects. However, there is very little research about the substance basis and action mechanism of JWXS tablet. In this research, ultra-high-performance liquid chromatography-mass spectrometry (UPLC-MS) and network pharmacology were used to explore the substance basis and action mechanism of the JWXS tablet. Finally, 19, 79, 22, 22 and 39 constituents were identified in the extracts of TZS, CP, SY, CMY and SZ, respectively. Based on these findings, a total of 104 ingredients were identified in JWXS tablet and 29 potentially absorbed ingredients were detected in rat plasma. The results of network pharmacology indicated that the inhibition of gastric acid secretion, the regulation of gastrointestinal motility, inflammation and immune response were the key approaches for treating FD with JWXS tablet. The material basis and potential action mechanism of JWXS tablet in treating FD were comprehensively clarified for the first time. This study will improve our understanding of JWXS tablet.

Current opinion: functional dyspepsia

PURPOSE OF REVIEW

Functional dyspepsia is a common gastrointestinal disease that is under-recognized and under-diagnosed. It is a complex disorder of gut-brain interaction with no FDA-approved treatment options. The purpose of this review is to highlight updates in the proposed pathophysiology and present new data regarding potential therapies for functional dyspepsia.

RECENT FINDINGS

Alterations in the intestinal microbiome and integrity of the intestinal membrane may play a crucial role in the pathogenesis of functional dyspepsia. The low FODMAP diet, in addition to modulating the microbiome with antibiotics and probiotics, are targets for large future studies. Novel methods of delivery of gut-brain therapies have shown promising results, especially virtual reality.

SUMMARY

The pathophysiology and management of functional dyspepsia is complex and there is still much unknown; however, continued research is identifying new targets for treatment. New and more targeted treatment options provide clinicians a variety of tools to offer patients with functional dyspepsia.

Differences in Prevalence and Psychosocial Characteristics of Irritable Bowel Syndrome According to Rome III and Rome IV Criteria in Medical and Nursing Students

Background/Aims

In Korea, changes in the prevalence of irritable bowel syndrome (IBS) after the Rome IV update have not been extensively studied. The aim of this study is to compare the prevalence and psychosocial risk factors of IBS according to Rome III and Rome IV criteria in medical and nursing students.

Methods

From August 13, 2021 to October 22, 2021, participants were enrolled and surveyed online. The survey includes general and specific questions for disease diagnosis and regarding participants' social and psychological characteristics using the 36-item short form survey, the Brief Encounter Psychosocial Instrument-Korean version, and the Hospital Anxiety and Depression Scale.

Results

In total, 338 medical students and 102 nursing students completed the survey. IBS was diagnosed in 78 students (17.7%) using Rome III criteria and in 51 students (11.6%) using Rome IV criteria. Significant differences in physical functioning score and severity score were observed between patients diagnosed using Rome IV criteria and patients diagnosed using Rome III criteria. Multiple logistic regression revealed that severity score (adjusted odds ratio = 1.01; 95% confidence interval: 1.00-1.21; P = 0.022) is the only predictor of IBS that differentiates Rome IV criteria from Rome III criteria.

Conclusions

Even after updating the Rome IV diagnostic criteria, the prevalence of IBS in medical and nursing students in Korea remained high. Patients who met the Rome IV criteria had more severe symptoms and lower quality of life than patients who met the Rome III criteria.

Silent Struggles Within: Alexithymia Unveiled in Irritable Bowel Syndrome: A Systematic Review and Meta-analysis

Background/Aims

In recent years, the presence of alexithymia in patients with irritable bowel syndrome (IBS) has gained more attention, and several studies have evaluated this relationship. However, no clear conclusion has been reported yet. Therefore, we conducted a systematic review and meta-analysis to better understand the association between IBS and alexithymia.

Methods

We performed a systematic search on the medical databases PubMed, EMBASE, and Scopus using predefined keywords to identify observational studies assessing the association between IBS and alexithymia. The included studies diagnosed IBS using the Rome criteria, and alexithymia was evaluated using the 20-item Toronto Alexithymia Scale (TAS-20) score. We used The Newcastle-Ottawa Scale to evaluate the quality of included studies. The primary summary outcome was the mean difference in TAS-20 scores.

Results

We included 7 studies involving 1,513 individuals in our qualitative analysis, with 6 of them included in our quantitative analysis. All studies were considered to be of satisfactory quality according to the Newcastle-Ottawa Scale criteria. We found significantly higher TAS-20 scores in IBS patients compared to controls (8.063 [95% CI, 2.554-13.572]). However, no significant mean difference in TAS-20 scores was observed in IBS vs inflammatory bowel disease patients (0.884 [95% CI -2.536-4.304]).

Conclusions

We demonstrated that IBS is associated with an increased risk of developing alexithymia. However, our study did not show a significant difference in TAS-20 scores between patients with IBS compared to inflammatory bowel disease.

Validating Simple Modifications to the Rome IV Criteria for the Diagnosis of Irritable Bowel Syndrome in Secondary Care

BACKGROUND

The Rome IV criteria for irritable bowel syndrome (IBS) may be too restrictive for clinical practice and research.

AIMS

To validate the Rome IV criteria and study the diagnostic performance of simple modifications to them.

METHODS

We collected symptom data from consecutive adults with suspected IBS seen in a single clinic. We used a reference standard to confirm IBS (presence of lower abdominal pain associated with altered stool form or frequency; no evidence of organic gastrointestinal disease after limited investigation). We applied Rome IV criteria, but also two modifications. First, we re-incorporated abdominal discomfort but kept symptom frequency required for both abdominal pain and discomfort to at least 1 day per week. Second, we included only abdominal pain but relaxed symptom frequency back to 3 days per month. We calculated sensitivity, specificity and positive and negative likelihood ratios (LRs), with 95% confidence intervals (CIs), for each diagnostic criterion.

RESULTS

We recruited 170 patients (76.5% female, mean age 37.9 years). Sensitivity and specificity of the Rome IV criteria were 82.1% and 85.1%, respectively; positive and negative LRs were 5.51 (95% CI 2.95-11.3) and 0.21 (95% CI 0.14-0.31), respectively. Modifying the criteria by relaxing the frequency of abdominal pain to 3 days per month led to the best performance [sensitivity 90.2%, specificity 85.1%, positive LR 6.06 (95% CI 3.25-12.2), and negative LR 0.11 (95% CI 0.07-0.19)].

CONCLUSIONS

The Rome IV criteria performed well in diagnosing IBS. A simple modification relaxing the required frequency of abdominal pain improved their performance.

Diagnostic classification systems for disorders of gut-brain interaction should include psychological symptoms

BACKGROUND AND AIMS

The group of disorders known as Disorders of Gut Brain Interaction (DGBI) were originally labeled functional GI disorders and were thought to be disorders of the gastrointestinal tract that had several psychological conditions as comorbidities. Despite mounting evidence that psychological morbidity plays an innate role in the etiology and maintenance of DGBI, none of the Rome IV criteria include any measure of psychological symptoms. This study tested the hypothesis that individuals would cluster differently if GI symptoms alone were considered versus GI symptoms combined with measures of psychological symptoms.

METHODS

Data were obtained from the Rome Foundation Global Epidemiology Study measuring Rome IV GI symptoms, psychological measures and demographic characteristics. Latent profile models were used to cluster individuals based on (i) GI symptoms only (GI only) and then (ii) GI and psychological measures (GI + Psych).

KEY RESULTS

Individuals clustering into the same group of individuals whether formed via GI only or GI + Psych, ranged from 96% for a 2-class solution (the most simplistic) to 76% with 6 classes (the parsimonious system) and 59% with twenty-two classes (mimicking Rome IV). The generalisability of this finding between six geographic regions was confirmed with agreement varying between 95%-97% for 2 clusters and 71-79% for 6 classes and 51%-63% for 22 classes. These findings were also consistent between DGBI (range 94% with 2 classes to 50% with 22 classes) and non-DGBI (range 97% with 2 clusters to 65% with 22 classes) groups.

CONCLUSIONS & INFERENCES

Our data suggest that considering psychological as well as gastrointestinal symptoms would lead to a different clustering of individuals in more complex, and accurate, classification systems. For this reason, future work on DGBI classification should consider inclusion of psychological traits.

The causality between gut microbiota and functional dyspepsia: A two-sample Mendelian randomization analysis

To investigate the potential link between gut microbiota and functional dyspepsia (FD). Genome-wide association studies (GWAS) of gut microbiota and FD were used in Mendelian randomization (MR) research. Using the GWAS of 18,340 people, instrumental variables related to gut microbiota as an exposure factor were identified. In a GWAS investigation, 189,695 control individuals and 4376 FD patients were included as outcome variables. The primary analysis technique was inverse variance weighted analysis. The reliability of MR analysis results is tested using sensitivity analysis. Two-sample Mendelian randomization analysis revealed the presence of 7 gut microbiota associated to FD. In the inverse variance weighted analysis method, Order Erysipelotrichales (odds ratio (OR): 1.301; 95% confidence interval (CI): 1.016, 1.665; P = .037), Family Erysipelotrichales (OR: 1.301; 95% CI: 1.016, 1.665; P = .037), Genus Haemophilus (OR: 1.236; 95% CI 1.059, 1.442; P = .007), Genus Ruminiclostridium 9 (OR: 1.422; 95% CI: 1.078, 1.877; P = .013), Genus Lachnospiraceae NK4A 136 group (OR: 1.297; 95% CI: 1.059, 1.589; P = .012) was positively associated with FD. Class Gammaproteobacteria (OR: 0.705; 95% CI: 0.522, 0.952; P = .022) and Genus Erysipelatoclostridium (OR: 0.747; 95% CI: 0.628, 0.888; P = .001) were found to be inversely related to FD. There was no evidence of pleiotropy or heterogeneity in the sensitivity analysis. Our research provides evidence for a possible link between FD and a number of gut microbiota. The role that gut microbiota plays in the development of FD requires more investigation.

Biofeedback efficacy for outlet dysfunction constipation: Clinical outcomes and predictors of response by a limited approach

BACKGROUND

Functional defecation disorders (FDD) are a common etiology of refractory chronic constipation (CC). FDD diagnosis (dyssynergic defecation [DD] and inadequate defecatory propulsion [IDP]), requires diagnostic tests including anorectal manometry (ARM) and balloon expulsion test (BET). Biofeedback (BF) is the treatment of choice for DD. The aims of our study were to evaluate: the outcome of BF in a group of constipated patients with defecatory disorders of any etiology; the efficacy of two simple diagnostic tools in predicting BF outcome in the short-term.

METHODS

One hundred and thirty-one refractory CC patients failing the BET underwent BF therapy. Before BF, all patients underwent the following: ARM. Straining questionnaire. The answers were: "belly muscles"; "anal muscles"; "both"; "Don't know/No answer." Digital rectal examination augmented by abdominal palpation on straining (augmented-DRE). The BF therapist was blinded to ARM, straining questionnaire, and augmented-DRE results.

KEY RESULTS

Eighty-one patients responded to BF. Gender, age, and IBS-C showed no significant impact on BF response. Both DD and IDP responded equally to BF, while the rate of response in patients with isolated structural pelvic floor abnormalities was lower (p < 0.001). The answer "anal muscles" to straining questionnaire showed a strong association with BF response (p < 0.001). A lack in abdominal contraction and in anal relaxation on augmented-DRE were strongly associated with BF response (p < 0.01). Absence of manual maneuvers to facilitate defecation was associated with BF response (p < 0.001).

CONCLUSIONS & INFERENCES

BF is the therapy of choice for refractory constipation due to FDD of any etiology, inducing both clinical and anorectal physiology improvement in the short term. Comorbid IBS-C did not affect outcome while symptomatic isolated pelvic floor abnormalities appeared refractory to behavior treatment. The straining questionnaire and augmented-DRE outcomes showed a strong correlation with BF response and can be implemented in clinical practice to improve the management of constipated patients by prompting early referral to BF.

Sex Differences in Colonoscopy Indications and Findings: Results from a Large Multicenter Database

Background: Sex-based differences are common among diseases. We aimed to investigate the differences in colonoscopy indications and its findings between males and females. Methods: A large, multi-center, cross-sectional, retrospective study included all colonoscopies performed between 2016 and 2021 in seven endoscopy departments. The indications and findings of the procedures were compared between males and females. Results: A total of 151,411 (52.6%) women and 136,519 (47.4%) men were included, aged 56.54 ± 12.9 years and 56.59 ± 12.7. Cecal intubation was similar (95.6% vs 95.5%, p = 0.251). More females had excellent or good bowel preparation compared to males (71.4% vs 65.6%). Colonoscopy due to abdominal pain, constipation, diarrhea, and anemia was higher in females compared to males (15% vs 9.9%, 3.9% vs 2.2%, and 7.6% vs 4.9%, p < 0.001, respectively), while positive FOBT, rectal bleeding and post-polypectomy surveillance and screening were more common indications among males (9.5% vs 7.8%, 10.7% vs 7.8%, and 10.8% vs 7.1%, respectively). On colonoscopy, males were found to have significantly higher colorectal cancer and polyps (0.5% vs 0.4% and 35.1% vs 24.6%). Polyp detection rates were lower in females across all indications, whereas diverticulosis rates were higher in males. However, a clinically significant difference regarding diverticulosis was observed only in patients with anemia as the indication. Conclusions: Notable differences exist between males and females in terms of the indications and findings on colonoscopy. This highlights the need for identifying the factors contributing to these differences and the developing sex-specific approaches for the diagnosis and management of gastrointestinal diseases.

Factors Associated With Abdominal Pain in Patients With Active and Quiescent Ulcerative Colitis: A Multicohort Study

BACKGROUND

Abdominal pain can be an overlooked symptom in patients with ulcerative colitis (UC).

AIMS

The aim of this study was to investigate the prevalence and factors associated with abdominal pain in active and quiescent UC.

METHODS

Three study cohorts of adult UC patients were used. Cross-sectional cohorts I and II included 130 (46 active) and 288 (156 active) patients. Longitudinal cohort III included 83 patients with active disease at diagnosis that reached deep remission during follow-up. The Gastrointestinal Symptom Rating Scale was used to assess abdominal pain and other validated questionnaires to assess psychological distress, fatigue and quality of life (QoL).

RESULTS

In the two cross-sectional cohorts, 63% and 58% of the active vs. 54% and 33% of the quiescent UC patients reported abdominal pain (both p ≤ 0.02). In the longitudinal cohort, 71% had abdominal pain at diagnosis vs. 46% when in remission (p < 0.001). In multivariable models, symptoms of anxiety were associated with higher abdominal pain levels in both cross-sectional cohorts (OR 1.75 [IQR 1.11-2.76] and OR 1.99 [1.45-2.73]), whereas in cohort II, active disease (OR 2.68 [1.61-4.45]) and female sex (OR 2.03 [1.21-3.41]) were also associated with pain. QoL was negatively correlated with higher levels of abdominal pain, both in active and quiescent disease.

CONCLUSIONS

Abdominal pain in UC is prevalent and associated with lower QoL in both active and quiescent disease. Associated factors are active disease, female sex and psychological symptoms, especially anxiety. We suggest considering a holistic approach when treating UC patients with abdominal pain.

Cerebral cortex changes in FD, IBS, and GERD: A Mendelian randomization study

BACKGROUND

Prospective and cross-sectional studies have reported an association between functional gastrointestinal disorders and anxiety and depression. However, the causal relationship is unclear. Therefore, we used Mendelian randomization (MR) to determine the causal effects of common gastrointestinal disorders on cortical structures.

METHODS

Genome-wide association study (GWAS) data for functional dyspepsia (FD), irritable bowel syndrome (IBS), and gastroesophageal reflux disease (GERD) were obtained from 329,262, 16,792, and 602,604 Europeans, respectively. GWAS cerebral cortical architecture data for cortical thickness (TH) and surface area (SA) were obtained from 51,665 MRI scans. MR was used to analyze the casual relationship between FD, IBS, GERD, and cortical structures. Inverse-variance weighted, weighted median, and MR-Egger tests were performed as assessment indicators. We also evaluated heterogeneity and pleiotropy.

RESULTS

The results revealed that FD significantly decreases the TH in the rostral anterior cingulate cortex (βTH = -0.022 mm; 95%CI: -0.035 mm to -0.009 mm2; PTH = 6.89 × 10-4), and IBS significantly decreases the SA of the pars triangularis (βSA = -21.91 mm2; 95%CI: -32.99 mm to -10.83 mm2; PSA = 1.06 × 10-4), precuneus (βSA = -47.53 mm2; 95%CI: -73.57 mm to-21.48 mm2; PSA = 3.48 × 10-4) and superior frontal regions (βSA = -78.70 mm2; 95%CI: -122.61 mm to -34.78 mm2; PSA = 4.4 × 10-4). At the local functional level, GERD significantly increases the SA of the inferior temporal region (βSA = -113.58 mm2, 95%CI: -113.58 mm to -39.01 mm2, PSA = 6.05 × 10-5).

CONCLUSIONS

FD, IBS and GERD can affect the cerebral cortex architecture through the brain-gut axis, thus increasing the risks of mental illness and cognitive dysfunction.

Combined MRI, high-resolution manometry and a randomised trial of bisacodyl versus hyoscine show the significance of an enlarged colon in constipation: the RECLAIM study

BACKGROUND

Colonic motility in constipation can be assessed non-invasively using MRI.

OBJECTIVE

To compare MRI with high-resolution colonic manometry (HRCM) for predicting treatment response.

DESIGN

Part 1: 44 healthy volunteers (HVs), 43 patients with irritable bowel syndrome with constipation (IBS-C) and 37 with functional constipation (FC) completed stool diaries and questionnaires and underwent oral macrogol (500-1000 mL) challenge. Whole gut transit time (WGTT), segmental colonic volumes (CV), MRI-derived Motility Index and chyme movement by 'tagging' were assessed using MRI and time to defecation after macrogol recorded. Left colonic HRCM was recorded before and after a 700 kcal meal. Patients then proceeded to Part 2: a randomised cross-over study of 10-days bisacodyl 10 mg daily versus hyoscine 20 mg three times per day, assessing daily pain and constipation.

RESULTS

Part 1: Total CVs median (range) were significantly greater in IBS-C (776 (595-1033)) and FC (802 (633-951)) vs HV (645 (467-780)), p<0.001. Patients also had longer WGTT and delayed evacuation after macrogol. IBS-C patients showed significantly reduced tagging index and less propagated pressure wave (PPW) activity during HRCM versus HV. Compared with FC, IBS-C patients were more anxious and reported more pain. Abnormally large colons predicted significantly delayed evacuation after macrogol challenge (p<0.02), impaired manometric meal response and reduced pain with bisacodyl (p<0.05).Part 2: Bisacodyl compared with hyoscine increased bowel movements but caused more pain in both groups (p<0.03).

CONCLUSION

An abnormally large colon is an important feature in constipation which predicts impaired manometric response to feeding and treatment responses. HRCM shows that IBS-C patients have reduced PPW activity.

TRIAL REGISTRATION NUMBER

The study was preregistered on ClinicalTrials.gov, Reference: NCT03226145.

Mast cell modulation: A novel therapeutic strategy for abdominal pain in irritable bowel syndrome

Irritable bowel syndrome (IBS) is one of the most prevalent gastrointestinal disorders characterized by recurrent abdominal pain and an altered defecation pattern. Chronic abdominal pain represents the hallmark IBS symptom and is reported to have the most bothersome impact on the patient's quality of life. Unfortunately, effective therapeutic strategies reducing abdominal pain are lacking, mainly attributed to a limited understanding of the contributing mechanisms. In the past few years, exciting new insights have pointed out that altered communication between gut immune cells and pain-sensing nerves acts as a hallmark driver of IBS-related abdominal pain. In this review, we aim to summarize our current knowledge on altered neuro-immune crosstalk as the main driver of altered pain signaling, with a specific focus on altered mast cell functioning herein, and highlight the relevance of targeting mast cell-mediated mechanisms as a novel therapeutic strategy for chronic abdominal pain in IBS patients.

Pharmacological potential of natural medicine Astragali Radix in treating intestinal diseases

Due to changes in diet and lifestyle, the prevalence of intestinal diseases has been increasing annually. Current treatment methods exhibit several limitations, including adverse reactions and drug resistance, necessitating the development of new, safe, and effective therapies. Astragali Radix, a natural medicine utilized for over two millennia, offers unique advantages in treating intestinal ailments due to its multi-component and multi-target properties. This study aims to review the effective components of Astragali Radix that provide intestinal protection and to explore its pharmacological effects and molecular mechanisms across various intestinal diseases. This will provide a comprehensive foundation for using Astragali Radix in treating intestinal diseases and serve as a reference for future research directions. The active components of Astragali Radix with protective effects on the intestines include astragaloside (AS)-IV, AS-III, AS-II, astragalus polysaccharide (APS), cycloastagenol, calycosin, formononetin, and ononin. Astragali Radix and its active components primarily address intestinal diseases such as colorectal cancer (CRC), inflammatory bowel disease (IBD), and enterocolitis through mechanisms including anti-inflammatory actions, antioxidative stress responses, anti-proliferation and invasion activities, regulation of programmed cell death, immunoregulation, restoration of the intestinal epithelial barrier, and modulation of the intestinal microbiota and its metabolites. Consequently, Astragali Radix demonstrates significant intestinal protective activity and represents a promising natural treatment for intestinal diseases. However, the pharmacological actions and mechanisms of some active components in Astragali Radix remain unexplored. Moreover, further comprehensive toxicological and clinical studies are required to ascertain its safety and clinical effectiveness.

The Diagnosis and Management of Chronic Constipation in Italy: Results from a Survey Conducted among Italian Gastroenterologists

Background: Chronic constipation (CC) is one of the most common disorders of gut-brain interaction (DGBI). The management of CC requires specific skills due to its complex and multifactorial pathophysiology and its multistep treatment. The aims of this study were to evaluate the availability and the use of diagnostic tools for CC in Italy and the therapeutic management of CC by Italian gastroenterologists (GEs). Methods: A survey was conducted during the 28th meeting of the Italian Federation of Digestive Disease Societies (FISMAD; Rome, Italy, 11-14 May 2022). The survey explored the presence of a clinic dedicated to DGBIs, the availability and the use of specific diagnostic tools, the routine use of digital rectal examination (DRE), and the therapeutic approach to CC by Italian GEs. Results: The survey was taken by 236 GEs. The most significant results were that 42% of respondents had a clinic dedicated to DGBI in their institute; DRE was regularly performed by 56.8% of GEs when evaluating a CC patient; young GEs (≤40 years) performed DRE less frequently than older ones (p < 0.001); anorectal manometry was available to 44.3% of GEs; balloon expulsion test (BET) was available to 19.1% of GEs; GEs with a clinic dedicated to DGBI had more frequent access to anorectal physiology testing (p < 0.001); diet and lifestyle advice were the most frequently prescribed treatments; and fiber and macrogol were the second and third most prescribed treatments, respectively. Conclusions: The survey provides an interesting picture of CC management by Italian GEs. The results are in line with previous data collected about 10 years ago among Italian GEs ("CHRO.CO.DI.T.E study"); DRE is still rarely performed by Italian GEs (particularly by young GEs). The availability of anorectal physiology testing is still limited, and BET, which could be easily performed in everyday clinical settings, is rarely performed. Lifestyle suggestions, macrogol and fiber are the preferred treatment, as recommended by all guidelines. These results will be useful to identify as yet unmet educational needs and critical issues to improve CC management.

Perceived healthiness of foods, food avoidance and diet-related anxiety in individuals with self-reported irritable bowel syndrome: a cross-sectional study

BACKGROUND

Irritable bowel syndrome (IBS) is a common gastrointestinal disorder in which the intake of food is known to exacerbate symptoms. Experiencing food related symptoms can lead to avoidance of food, and cause anxiety related to food intake. We aimed to explore perceptions of the healthiness of food, food avoidance, and food-related worry and anxiety among individuals with and without IBS.

METHODS

This study was based on a survey conducted in January-February 2017. In total, 2000 participants aged 20-65 were invited by postal letter randomly obtained through the Swedish state personal address register. The questionnaire included aspects of socioeconomic position, different disorders including IBS and food intolerances, food avoidance, and food-related worry or anxiety.

RESULTS

In total, 538 participants were included in this study, of whom 8.4% (n = 45) reported having IBS. There were few differences regarding the perceived healthiness of foods between individuals with and without IBS. Participants with IBS avoided gluten (OR 3.45, p = 0.002), lactose (OR 5.0, p < 0.001) and alcohol (OR 2.0, p = 0.042) more frequently than individuals without IBS, and avoidance was driven by abdominal pain. Participants with IBS also reported feeling more worried and having anxiety about diet than those without IBS (p = 0.032 and p = 0.002, respectively).

CONCLUSION

This study indicates that individuals with IBS perceive most foods as equally healthy as individuals without IBS. Having IBS increases the odds of avoiding gluten, lactose, and alcohol. Worry and anxiety related to diet were more common among individuals with IBS, and these aspects need to be considered both in clinical practice and in future research.

Impact of Enteric Nervous Cells on Irritable Bowel Syndrome: Potential Treatment Options

Irritable bowel syndrome (IBS) is a condition that significantly impacts the lifestyle, health, and habits of numerous individuals worldwide. Its diagnosis and classification are based on the Rome criteria, updated periodically to reflect new research findings in this field. IBS can be classified into different types based on symptoms, each with distinct treatment approaches and some differences in their pathophysiology. The exact pathological background of IBS remains unclear, with many aspects still unknown. Recent research developments suggest that disorders in the brain-gut-microbiota axis are key contributors to the symptoms and severity of IBS. The central nervous system (CNS) interacts bidirectionally with intestinal processes within the lumen and the intestinal wall, with the autonomic nervous system, particularly the vagus nerve, playing an important role. However, the enteric nervous system (ENS) is also crucial in the pathophysiological pathway of IBS. The apeline-corticotropin-releasing factor (CRF)-toll-like receptor 4 (TLR4) signaling route via enteric glia and serotonin production in enteroendocrine cells at the enteric barrier are among the most well-understood new findings that affect IBS through the ENS. Additionally, the microbiota regulates neuronal signals, modifying enteric function by altering the number of enteric bacteria and other mechanisms. Given the limited therapeutic options currently available, it is essential to identify new treatment targets, with the brain-gut axis, particularly the enteric nervous system, being a promising focus. This study aims to delineate the molecular mechanisms that induce IBS and to suggest potential targets for future research and treatment of this potentially debilitating disease.

Adapted Low-FODMAP Diet in IBS Patients with and without Fibromyalgia: Long-Term Adherence and Outcomes

BACKGROUND/OBJECTIVES

A low-FODMAPs Diet (LFD) is considered a "second line" dietary strategy for irritable bowel syndrome (IBS) but, after a period of strict restriction of all FODMAP foods, it has to be adapted and tailored to each patient (AdLFD). Fibromyalgia often coexists with IBS in up to 65% of cases. Our aims were to evaluate if comorbid fibromyalgia influenced the long-term clinical outcomes and adherence to an AdLFD in IBS patients.

METHODS

IBS patients with or without fibromyalgia who had started an AdLFD were enrolled. Patients had been evaluated before starting the LFD (T0). After a mean follow-up of 62.5 ± 22.7 months (T1), they were re-evaluated using questionnaires on disease severity, bowel habits, psychological status, and adherence to AdLFD.

RESULTS

In total, 51 IBS patients entered the study. Nineteen of them had comorbid fibromyalgia. Thirty patients reported a reduction in symptom severity at T1 in comparison with T0. Despite some slight differences in single IBS Symptom Severity Score items, comorbid fibromyalgia did not influence the IBS-SSS total score at T1. Patients with comorbid fibromyalgia showed a higher Hospital Anxiety and Depression Scale (HADS) score at baseline. A total of 44 patients showed good long-term adherence to the AdLFD. All patients improved their HADS score and had long-term adherence to the AdLFD.

CONCLUSIONS

Comorbid fibromyalgia showed only a slight influence on long-term outcomes of an AdLFD on IBS symptoms, without affecting the relief of global symptoms. No influence on long-term adherence to AdLFD was detected. Hence, this approach can be taken into account in fibromyalgia patients for a nonpharmacological management of IBS symptoms. However, multicentric studies on larger samples would be welcome in the future.

Chronic nausea and vomiting syndrome and impact on quality of life

INTRODUCTION AND AIM

Chronic nausea and vomiting syndrome is a disorder of gut-brain interaction that affects the productive-age population. Our aim was to determine the association of this disorder with quality of life, workplace performance, and socioeconomic impact related to gastrointestinal health.

METHODS

A cross-sectional study on a Mexican population was conducted. The patients were classified as having chronic nausea and vomiting syndrome or other disorders of gut-brain interaction. A comparative analysis of quality of life, workplace productivity, annual medical consultations, and digestive health-related expenses was carried out, applying a logistic regression model.

RESULTS

One thousand patients were included, 79.2% of whom met the criteria for a disorder of gut-brain interaction. Of the 792 patients, 10.3% presented with chronic nausea and vomiting syndrome. Said syndrome was associated with a negative impact on usual activities (OR 4.34, 95% CI 1.90-9.30, p ≤ 0.001), pain/discomfort (OR 2.09, 95% CI 1.31-3.33, p ≤ 0.001), anxiety/depression (OR 2.08, 95% CI 1.30-3.40, p ≤ 0.001), workplace presenteeism (OR 3.96, 95% CI 2.47-6.44, p ≤ 0.001), and workplace absenteeism (OR 2.54, 95% CI 1.52-4.16, p ≤ 0.001). There was also a higher number of annual medical consultations for digestive health (p = 0.013), without generating a greater annual expense due to digestive health (p = 0.08).

CONCLUSIONS

Chronic nausea and vomiting syndrome produces a negative impact on quality of life, which could be secondary to its symptomatology or its association with anxiety and depression.

Relationship Between High Frequency Component of Heart Rate Variability and Delta EEG Power During Sleep in Women With Irritable Bowel Syndrome Compared to Healthy Women

OBJECTIVE

To explore the relationship between the high frequency (HF) heart rate variability (HRV) and electroencephalogram (EEG) delta band power in women with irritable bowel syndrome (IBS) versus healthy control women.

MATERIALS AND METHODS

Twenty women with IBS and twenty healthy controls were studied over three consecutive nights using polysomnography in a sleep laboratory. To avoid the first night effect, only second-night data were analyzed. Power spectral analysis was applied to HRV and EEG recordings. The linear system coherence/phase analysis assessed the relationship between normalized HF power of HRV and normalized delta band power of EEG during the first four NREM-REM sleep cycles.

RESULTS

Women with IBS exhibited a significantly higher percentage of NREM sleep, higher normalized HF, lower normalized low frequency (LF) and decreased LF/HF ratio of HRV in the first four NREM-REM sleep cycles compared to controls. Additionally, their normalized delta band power was significantly lower in these sleep cycles and over the whole night. The phase shift between HF and delta band power was significantly longer in the IBS group. While the coherence between normalized HF and normalized delta band power was lower in the IBS group, the difference was not statistically significant.

CONCLUSIONS

The coherence/phase analysis showed a dysregulated interaction between autonomic and central nervous systems in women with IBS, manifested by increased lag time between cardiac and EEG delta band power compared to healthy controls. Whether this dysregulation contributes to the pathophysiology of IBS remains to be determined.

Patients' experiences of dietary changes during a structured dietary intervention for irritable bowel syndrome

BACKGROUND

Diet plays an important role in management of gastrointestinal (GI) symptoms in patients with irritable bowel syndrome (IBS). Restrictive diets have gained popularity as treatment for IBS, but no studies have examined the patients' experiences of implementing such diets. Thus, the present study aimed to explore the experience of patients with IBS undergoing a structured dietary intervention.

METHODS

Using inductive content analysis, semi-structured interviews were conducted in 19 patients with IBS, who were recruited from a randomised controlled trial evaluating two different restrictive diets for 4 weeks: a diet low in total carbohydrates; and a diet low in fermentable oligo-, di- and monosaccharides and polyols (i.e., FODMAP) combined with traditional IBS dietary advice.

RESULTS

Three main themes developed from the qualitative analysis and together they describe the dietary intervention as supportive, as well as the dietary changes as challenging and contributing to reflection. Patients found the dietary support effective in both initiating and adhering to their dietary changes. Despite the support, the implementation of the diet was perceived as challenging when it interfered with other important aspects of their lives. However, going through the dietary change process, the patients began to reflect on their eating behaviours, which enabled individual dietary adjustments. The adjustments that patients maintained were not only a result of alleviation of GI symptoms, but also based on personal preferences.

CONCLUSIONS

Patients with IBS undergoing restrictive diets appear to benefit from structured support. However, considering the individual patient's life situation and personal preferences, individualised dietary options should be encouraged to achieve long-term dietary changes.

Low-dose titrated amitriptyline as second-line treatment for adults with irritable bowel syndrome in primary care: the ATLANTIS RCT

Background

Irritable bowel syndrome, characterised by abdominal pain and a change in stool form or frequency, is most often managed in primary care. When first-line therapies are ineffective, National Institute for Health and Care Excellence guidelines suggest considering low-dose tricyclic antidepressants as second-line treatment, but their effectiveness in primary care is unknown and they are infrequently prescribed by general practitioners.

Objective

To evaluate the clinical and cost-effectiveness of low-dose titrated amitriptyline as a second-line treatment for irritable bowel syndrome in primary care.

Design

A pragmatic, randomised, multicentre, two-arm, double-blind, placebo-controlled trial. A nested, qualitative study explored participant and general practitioner experiences of treatments and trial participation, and implications for wider use of amitriptyline for irritable bowel syndrome in primary care. Participants, clinicians, investigators and analysts were masked to allocation.

Setting

Fifty-five general practices in three regions in England (Wessex, West of England, West Yorkshire).

Participants

Patients aged ≥ 18 years meeting Rome IV criteria for irritable bowel syndrome with ongoing symptoms after trying first-line treatments and no contraindications to TCAs.

Intervention

Amitriptyline 10 mg once-daily, self-titrated by participants to a maximum of 30 mg once-daily or matched placebo for 6 months. Participants randomised 1 : 1 with most having the option to continue blinded treatment for a further 6 months.

Main outcome measures

The primary participant-reported outcome was the effect of amitriptyline on global irritable bowel syndrome symptoms at 6 months, measured using the irritable bowel syndrome Severity Scoring System, with a 35-point between-group difference defined as the minimum clinically important difference. The key secondary outcome was the proportion of participants reporting subjective global assessment of relief at 6 months, defined as somewhat, considerable, or complete relief of symptoms. Other secondary outcomes included: effect on global symptoms, via the irritable bowel syndrome Severity Scoring System, and subjective global assessment of relief of irritable bowel syndrome symptoms at 3 and 12 months; effect on somatic symptom-reporting at 6 months; anxiety an-d depression scores; ability to work and participate in other activities at 3, 6 and 12 months; acceptability, tolerability and adherence to trial medication.

Results

Four hundred and sixty-three participants were randomised to amitriptyline (232) or placebo (231). An intention-to-treat analysis of the primary outcome showed a significant difference in favour of amitriptyline for irritable bowel syndrome Severity Scoring System score between arms at 6 months [-27.0, 95% confidence interval (CI) -46.9 to -7.10; p = 0.008]. For the key secondary outcome of subjective global assessment of relief of irritable bowel syndrome symptoms, amitriptyline was superior to placebo at 6 months (odds ratio 1.78, 95% CI 1.19 to 2.66; p = 0.005). Amitriptyline was superior to placebo across a range of other irritable bowel syndrome symptom measures but had no impact on somatoform symptom-reporting, anxiety, depression, or work and social adjustment scores. Adverse event trial withdrawals were more common with amitriptyline (12.9% vs. 8.7% for placebo) but most adverse events were mild. The qualitative study thematically analysed 77 semistructured interviews with 42 participants and 16 GPs. Most participants found the self-titration process acceptable and empowering.

Conclusions

General practitioners should offer low-dose amitriptyline to patients with irritable bowel syndrome whose symptoms do not improve with first-line therapies. Guidance and resources should support GP-patient communication to distinguish amitriptyline for irritable bowel syndrome from use as an antidepressant and to support patients managing their own dose titration.

Study registration

This trial is registered as ISRCTN48075063.

Funding

This award was funded by the National Institute for Health and Care Research (NIHR) Health Technology Assessment programme (NIHR award ref: 16/162/01) and is published in full in Health Technology Assessment Vol. 28, No. 66. See the NIHR Funding and Awards website for further award information.

Clinical trial: Effects of treatment with a vibrating capsule in patients with severe chronic constipation

BACKGROUND

There is little information on the effectiveness of therapies for severe chronic constipation. In a phase 3 trial, we previously demonstrated that a vibrating capsule was significantly more efficacious than a placebo in chronic constipation.

AIM

To examine the effects of a vibrating capsule and placebo on symptoms and health-related quality of life (HRQoL) in patients with severe chronic constipation.

METHODS

We performed a post hoc analysis of phase 3, multicentre, randomised, double-blind, and placebo-controlled 8-week clinical trial of a vibrating capsule to specifically assess outcomes among subjects who reported 0 complete spontaneous bowel movements (CSBMs) during the 2-week baseline period. We assessed effects of treatment on bowel symptoms, patient satisfaction, and HRQoL. CSBM responders were defined as subjects with increases of ≥1 or ≥2 or ≥3 weekly CSBMs (CSBM1 or CSBM2, CSBM3, respectively) over baseline for ≥6 out of 8 weeks of treatment.

RESULTS

The severe chronic constipation subgroup comprised 175 (56%) of the 312 subjects. Significantly more subjects with severe chronic constipation who received the vibrating capsule than those who received the placebo were CSBM1 (44.9% vs. 20.9%, p = 0.007), CSBM2 (29.2% vs. 11.6%, p = 0.004), and CSBM3 (19.10% vs 6.98%, p = 0.017) responders. Straining effort, stool consistency, patient satisfaction, and HRQoL significantly improved in the severe chronic constipation subgroup. A mild vibrating sensation was reported in 10%.

CONCLUSION

The vibrating capsule significantly improved constipation-related symptoms and HRQoL in patients with severe constipation, affirming its efficacy and safety across the spectrum of chronic constipation.

Plasma Interleukin-13 Levels Correlate With the Severity of Symptoms Induced by Functional Dyspepsia

OBJECTIVE

Functional dyspepsia (FD) is a gastrointestinal functional disorder of the upper gastrointestinal tract that affects the quality of life of patients and poses a significant economic burden. It has been proposed that the local inflammatory immune response at the duodenum is associated with an increase in intestinal permeability, favoring the recruitment of Th2 cells and granulocyte degranulation. Moreover, systemic immune response could also be related to the symptoms of FD. The objective of this study was to evaluate the systemic immune response in Uruguayan patients with FD by analyzing the cytokine levels in plasma and the frequency of circulating T cells associated with duodenal recruitment.

PATIENTS AND METHODS

An analytic and cross-sectional study in 30 patients with FD and 15 healthy controls (HCs) was carried out. Patients were diagnosed with FD according to the Roma IV Committee definition. Cytokine levels were measured in plasma by a specific assay. Expression of α4β7 and CC chemokine receptor9 in circulating T cells was evaluated by flow cytometry.

RESULTS

Higher levels of interleukin (IL)-5, IL-13, and IL-8 and lower levels of IL-10 and IL-12p70 were detected in patients with FD than in HC. Furthermore, a positive linear correlation between IL-13 and the severity of FD symptoms was found. CD4 + T cells from patients with FD expressed higher levels of α4β7 and CC chemokine receptor9 than those from HC.

CONCLUSIONS

An increase of Th2-like cytokines and a positive correlation between the levels of plasma IL-13 and the severity of symptoms in patients with FD from Uruguay were detected.

Treatment for chronic idiopathic constipation: Use and satisfaction from a nationwide survey of US participants

BACKGROUND

Chronic idiopathic constipation (CIC) is a disorder of gut-brain interaction characterized by a variety of bowel movement-related and abdominal symptoms. A greater understanding of medication use and satisfaction with symptom control may provide insights to optimize patient care. Therefore, we explored these aspects of the disorder in adults with CIC.

METHODS

This study assessed data collected from a large nationwide survey of adult participants in the United States, querying demographics, clinical characteristics, and comorbid conditions, as well as medication use, care-seeking behaviors, and satisfaction with symptom control. Participants were grouped into the CIC cohort if they met Rome IV criteria, with controls matched 1:1 according to age, sex, race, region, and Charlson Comorbidity Index score. All data were self-reported.

KEY RESULTS

Two thousand five hundred and thirty-three participants with CIC were matched 1:1 to controls. In the CIC cohort, abdominal pain was the most reported symptom leading to medication use: 15.9% of respondents were receiving a prescription medication in addition to an over-the-counter medication, while 26.3% were taking neither. In addition, only one-third were satisfied with the control of their symptoms; however, satisfaction was significantly higher in respondents taking a prescription medication (p < 0.001). The proportion of reported comorbidities was significantly higher in the CIC cohort versus the control cohort, with chronic pain, anxiety, and depression among the highest (p < 0.001 for all).

CONCLUSIONS AND INFERENCES

This study emphasizes the need for better communication regarding prescription medications and their benefits, with the goal of further improving CIC patients' overall symptoms.

A real-world study of persistence and adherence to prescription medications in patients with chronic idiopathic constipation in the United States

BACKGROUND

At present, 4 prescription therapies have been approved by the US Food and Drug Administration for the treatment of chronic idiopathic constipation (CIC) in adults.

OBJECTIVES

To compare persistence with and adherence to prucalopride vs 3 other prescription medications for CIC in a US population.

METHODS

This retrospective, observational cohort study used data from the IBM MarketScan Commercial Claims and Encounters and Medicare Supplemental Databases (January 2015-June 2020). Inclusion criteria were patients (aged ≥18 years) with at least 1 prescription fill for prucalopride, lubiprostone, linaclotide, or plecanatide on or after April 2, 2019 (commercial availability of prucalopride), and at least 1 constipation-related diagnosis code. Persistence was assessed by time to discontinuation, and adherence was assessed by the proportion of days covered (PDC) and the proportion of patients who achieved PDC of at least 80%. Adjusted hazard ratios (HRs) for discontinuation and odds ratios for adherence were calculated.

RESULTS

A total of 14,700 patients (mean age = 48.3 years; female = 81.9%) were included (prucalopride, n = 675; lubiprostone, n = 1,591; linaclotide, n = 11,105; plecanatide, n = 1,329). After adjusting for confounding factors, the HRs for discontinuation were significantly higher for all comparator medications compared with prucalopride after 2 months (HR [95% CI]: lubiprostone, 1.70 [1.48-1.95]; linaclotide, 1.25 [1.10-1.41]; plecanatide, 1.31 [1.13-1.51], all P < 0.001). The unadjusted mean (SD) PDC was 0.53 (0.32) with prucalopride compared with 0.41 (0.31); P less than 0.001 with lubiprostone, 0.48 (0.31), P less than 0.05 with linaclotide, and 0.48 (0.29), P = 0.98 with plecanatide. The comparator medications were all associated with lower odds of achieving PDC of at least 80% relative to prucalopride (odds ratio [95% CI]: lubiprostone, 0.52 [0.40-0.69], P < 0.001; linaclotide, 0.73 [0.58-0.93], P = 0.009; plecanatide, 0.70 [0.53-0.93], P = 0.015).

CONCLUSIONS

The findings of this study indicate that prucalopride has higher treatment persistence and adherence compared with other CIC prescription medications. This research represents the first instance of a real-world claims study showcasing such outcomes.

Pain is a cardinal symptom cutting across Rome IV anatomical categories in disorders of gut-brain interaction: A network-based approach

INTRODUCTION

Disorders of gut-brain interaction (DGBI) are symptom-based disorders categorized by anatomic location but have high overlap and heterogeneity. Viewing DGBI symptoms on a spectrum (i.e. dimensionally) rather than categorically may better inform interventions to accommodate complex clinical presentations. We aimed to evaluate symptom networks to identify how DGBI symptoms interact.

METHODS

We used the Rome IV Diagnostic Questionnaire continuously/ordinally scored items collected from the Rome Foundation Global Epidemiology Study. We excluded participants who reported ≥1 organic/structural gastrointestinal disorder(s). We sought to (1) identify core symptoms in the DGBI symptom networks, (2) identify bridge pathways between Rome IV diagnostic categories (esophageal, bowel, gastroduodenal, anorectal), and (3) explore how symptoms group together into communities.

RESULTS

Of 54,127 adults, 20,229 met criteria for at least one DGBI (age mean = 42.2 ± 15.5; 57% female). General abdominal pain and epigastric pain were the core symptoms in the DGBI symptom network (i.e., had the strongest connections to other symptoms). Pain symptoms emerged as bridge pathways across existing DGBI diagnostic anatomic location (i.e., abdominal pain connected to chest pain, epigastric pain, rectal pain). Without a priori category definitions, exploratory network community analysis showed that symptoms grouped together into "pain," "gastroduodenal," and "constipation," rather than into groups by anatomic location.

CONCLUSION

Our findings suggest pain symptoms are central and serve as a key connection to other symptoms, crosscutting anatomic location. Future longitudinal research is needed to test symptom network relations longitudinally and investigate whether targeting pain symptoms (rather than anatomic- or disorder-specific symptoms) has clinical impact.

The COVID-19 pandemic as a modifier of DGBI symptom severity: A systematic review and meta-analysis

BACKGROUND

This SRMA reviewed and assessed the changes in the severity of disorders of gut-brain interaction (DGBI) symptoms during the COVID-19 pandemic, and evaluated factors associated with symptom severity changes.

METHODS

Electronic databases were searched until February 2024, for articles reporting on changes in symptom severity in DGBI patients during the COVID-19 pandemic. The proportion of DGBI patients who reported a change in their symptom severity were pooled using a random-effects model, and subgroup analyses were conducted to assess the effect of socio-cultural modifiers on symptom severity in DGBI.

KEY RESULTS

Twelve studies including 3610 DGBI patients found that 31.4% (95% CI, 15.9-52.5) of DGBI patients experienced symptom deterioration, while 24.3% (95% CI, 10.2-47.5) experienced improvement. Countries with high gross domestic product (GDP) had a 43.5% (95% CI, 16.3-75.2) likelihood of symptom deterioration, compared to 9.2% (95% CI, 1.4-42.2) in lower GDP countries. Similarly, countries with low COVID fatality rates had a 60.1% (95% CI, 19.7-90.3) likelihood of symptom deterioration, compared to 18.3% (95% CI, 7.8-36.9) in higher fatality rate countries. Countries with lenient COVID policies had a 58.4% (95% CI, 14.1-92.3) likelihood of symptom deterioration, compared to 19% (95% CI, 8.2-38.1) in countries with stricter policies. Patients in high vaccine hesitancy countries had a 51.4% (95% CI, 19.5-82.2) likelihood of symptom deterioration, compared to 10.6% (95% CI, 2.7-33.4) in low vaccine hesitancy countries.

CONCLUSIONS & INFERENCES

This meta-analysis reveals that a significantly higher proportion of DGBI patients experienced deterioration of symptoms during the COVID-19 pandemic. Various sociocultural, economic and environmental factors potentially modify the effects of the COVID-19 pandemic on DGBI.

Rifaximin and alternative agents in the management of irritable bowel syndrome: A comprehensive review

Rifaximin, a broad-spectrum antibiotic, boasts a unique chemical composition and pharmacokinetic profile, rendering it highly effective in treating irritable bowel syndrome (IBS). Its minimal systemic absorption confines its impact to the gastrointestinal (GI) tract, where it yields significant therapeutic benefits. This review examines rifaximin's physico-chemical attributes and its role in managing IBS symptoms. Its molecular structure facilitates intestinal lumen retention postoral administration, minimizing systemic exposure and adverse effects. This targeted action is crucial in addressing the gut microbiota's role in IBS pathophysiology. By modifying microbial populations and their metabolite production, rifaximin mitigates symptoms like bloating, irregular bowel habits, and abdominal pain associated with IBS. It achieves this by reducing pathogenic bacteria and altering bacterial metabolism, enhancing mucosal and immune function. Clinical trials affirm rifaximin's superiority over placebo and conventional therapies in alleviating overall IBS symptoms and addressing small intestine bacterial overgrowth (SIBO). Despite its promising efficacy and sustained symptom relief, further research is essential to optimize long-term effectiveness and dosing regimens. Rifaximin stands as a vital treatment option for IBS due to its distinctive properties and clinical utility; yet, ongoing investigation is imperative for maximizing its therapeutic benefits.

The combination of L-menthol and caraway oil does not affect gastric function but increases hunger in healthy subjects

BACKGROUND

The heterogeneous character of functional gastrointestinal disorders, recently renamed into disorders of gut-brain interaction, makes finding effective treatment options challenging. Compared to synthetic drugs, phytotherapy can have broader pharmacological effects and is often better tolerated. This study aimed to investigate the effect of peppermint oil and caraway oil (POCO) on gastric function and symptom levels in 32 healthy subjects in a single-blinded, placebo-controlled, randomized, parallel design.

METHODS

Gastric emptying rate was assessed using a 13C-breath test. Intragastric pressure was measured using high-resolution manometry in fasted state and during intragastric infusion of a nutrient drink (350 mL or until full satiation). GI symptoms were rated on a 100 mm VAS. Data were analyzed using linear mixed models.

KEY RESULTS

POCO had no effect on intragastric pressure in fasted or fed state (p > 0.08 for all). No significant differences in gastric emptying rate were observed (p = 0.54). In the fasted state, a stronger increase in hunger and decrease in satiety were observed following POCO (p = 0.016 and p = 0.008, respectively). No differences in hunger and satiety were observed in the fed state (p > 0.31 for all). POCO induced less epigastric burning, bloating, and fullness (p < 0.05 for all).

CONCLUSIONS

Acute POCO administration did not affect gastric function in healthy subjects, but increased fasted hunger ratings. The effects of POCO on gastric function and hunger sensations in patients with disorders of gut-brain interaction, and the contribution to symptom improvement, needs to be elucidated in future studies.

Stress triggers irritable bowel syndrome with diarrhea through a spermidine-mediated decline in type I interferon

Irritable bowel syndrome with diarrhea (IBS-D) is a common and chronic gastrointestinal disorder that is characterized by abdominal discomfort and occasional diarrhea. The pathogenesis of IBS-D is thought to be related to a combination of factors, including psychological stress, abnormal muscle contractions, and inflammation and disorder of the gut microbiome. However, there is still a lack of comprehensive analysis of the logical regulatory correlation among these factors. In this study, we found that stress induced hyperproduction of xanthine and altered the abundance and metabolic characteristics of Lactobacillus murinus in the gut. Lactobacillus murinus-derived spermidine suppressed the basal expression of type I interferon (IFN)-α in plasmacytoid dendritic cells by inhibiting the K63-linked polyubiquitination of TRAF3. The reduction in IFN-α unrestricted the contractile function of colonic smooth muscle cells, resulting in an increase in bowel movement. Our findings provided a theoretical basis for the pathological mechanism of, and new drug targets for, stress-exposed IBS-D.

Plant-derived exosomes in therapeutic nanomedicine, paving the path toward precision medicine

BACKGROUND

Plant-derived exosomes (PDEs), are nanoscale vesicles secreted by multivesicular bodies, play pivotal roles in critical biological processes, including gene regulation, cell communication, and immune defense against pathogens. Recognized for their potential health-promoting properties, PDEs are emerging as innovative components in functional nutrition, poised to enhance dietary health benefits.

PURPOSE

To describe the efficacy of PDEs in nanoform and their application as precision therapy in many disorders.

STUDY DESIGN

The design of this review was carried out in PICO format using randomized clinical trials and research articles based on in vivo and in vitro studies.

METHODS

All the relevant clinical and research studies conducted on plant-derived nanovesicle application and efficacy were included, as retrieved from PubMed and Cochrane, after using specific search terms. This review was performed to determine PDEs' efficacy as nanomedicine and precision therapy. Sub-group analysis and primary data were included to determine the relationship with PDEs.

RESULT

PDEs are extracted from plant materials using sophisticated techniques like precipitation, size exclusion, immunoaffinity capture, and ultracentrifugation, encapsulating vital molecules such as lipids, proteins, and predominantly microRNAs. Although their nutritional impact may be minimal in small quantities, the broader application of PDEs in biomedicine, particularly as vehicles for drug delivery, underscores their significance. They offer a promising strategy to improve the bioavailability and efficacy of therapeutic agents carrying nano-bioactive substances that exhibit anti-inflammatory, antioxidant, cardioprotective, and anti-cancer activities.

CONCLUSION

PDEs enhance the therapeutic potency of plant-derived phytochemicals, supporting their use in disease prevention and therapy. This comprehensive review explores the multifaceted aspects of PDEs, including their isolation methods, biochemical composition, health implications, and potential to advance medical and nutritional interventions.

New Pipeline for Analysing Fruit Proteolytic Products Used as Digestive Health Nutraceuticals

Proteolytic products are extensively used in the nutraceutical sector to improve protein digestion and muscle quality in target populations (e.g., athletes or elderly). These products are processed using techniques that often lead to low purity but competitive pricing. Despite their widespread use and well-established production methods, the industry lacks standardized analytical methods for assessing these products and detecting potential fraud. This study proposes a comprehensive and harmonized pipeline for their analysis, which includes quantifying total soluble protein and proteolytic activity, as well as the determination of product stability and protein profile using SDS-PAGE and proteomic techniques. Despite the fact that protease extracts from pineapple had the highest protein content, most of the bromelain remained inactive, unlike in kiwi and papaya. SDS-PAGE revealed partial protein degradation of pineapple extracts, whereas kiwi extracts reflected a lower purification level but a higher protein integrity. The application of proteomic approaches strengthened the identification and origin tracing of the proteases. This study contributes to the development of a robust framework for analyzing proteolytic extracts, spanning from soluble protein quantification to protein profiling and activity determination. It may also ensure reliable supplier selection, high-quality manufacturing practices, and the implementation of optimal storage and formulation strategies in the nutraceutical industry.

Evaluating Equity in Clinical Trial Accessibility: An Analysis of Demographic, Socioeconomic, and Educational Disparities in Irritable Bowel Syndrome Drug Trials

INTRODUCTION

Irritable bowel syndrome (IBS), a disorder of gut-brain interaction, imposes a significant economic burden because of its high prevalence and the chronic nature of its symptoms. IBS currently has 7 United States Food and Drug Administration-approved treatments. Despite efforts to improve diversity in randomized controlled trials' participation, significant disparities remain in various medical fields; yet, these have not been thoroughly examined within the context of IBS. We aimed to investigate the demographic, socioeconomic, educational, and geographic disparities in IBS drug trials.

METHODS

We conducted a systematic review of phase 3 randomized controlled trials on United States Food and Drug Administration-approved drugs for the treatment of IBS with constipation and IBS with diarrhea in the United States. Data on participant demographics and trial site locations were extracted and analyzed to identify disparities.

RESULTS

Our analysis included 17 studies encompassing 21 trials with 17,428 participants. Approximately 77.3% of participants were female, with a mean age of 45.4 years. Race was reported in 95% of the trials, but only 35% disclosed ethnicity. White participants constituted the majority at 79.3%. Hispanics accounted for only 5.9%. Counties without trial sites had smaller average population sizes compared with trial and trial-adjacent counties. Socioeconomic indicators such as poverty rates, median household income, educational attainment, and broadband internet access were lower in counties without trial sites, with higher average Area Deprivation Index scores indicating greater deprivation.

DISCUSSION

The findings highlight significant disparities in IBS trial participation across race, ethnicity, gender, and socioeconomic backgrounds. This raises potential concerns about generalizability of trial outcomes and underscores the need for strategies to enhance inclusivity in clinical research.

Review: Food-induced mucosal alterations visualized using endomicroscopy

Confocal laser endomicroscopy (CLE) is a novel technique allowing real time in vivo microscopy during standard endoscopy. Recently, acute mucosal alterations after food administration visualized by CLE have been linked to symptoms in irritable bowel syndrome (IBS). Interestingly, the observed reactions occurred in subjects without demonstrable allergic sensitization to food-this is in line with mechanistic research showing local but not systemic allergic sensitization to foods in an animal model for IBS. Here, European experts conducting CLE with food administration provide a narrative review of the available literature and propose practical guidance on the use of this technique. CLE allows physicians to observe acute mucosal reactions after the application of food to the duodenal mucosa in patients with functional gastrointestinal disorders. Some open-label interventions show a symptomatic benefit when patients exclude the nutrient that triggered an acute mucosal reaction. However, many technical, mechanistic, and clinical questions remain unanswered to date. Technically, the interobserver variability and learning curve requires systematic evaluation and criteria or cutoffs for alterations require validation. Mechanistic studies are needed to enhance our understanding of the mechanisms underlying observed alterations. Finally, rigorous blinded controlled studies are needed to assess a link of these observed alterations with symptom generation. CLE offers a platform allowing scientific insights related to food induced acute mucosal alterations. However, many questions remain unanswered, and more research is warranted to understand the role of acute mucosal alterations visualized upon food administration in IBS pathophysiology and treatment.

Traditional Chinese medicine for functional gastrointestinal disorders and inflammatory bowel disease: narrative review of the evidence and potential mechanisms involving the brain-gut axis

Functional gastrointestinal disorders (FGIDs) and inflammatory bowel disease (IBD) are common clinical disorders characterized by recurrent diarrhea and abdominal pain. Although their pathogenesis has not been fully clarified, disruptions in intestinal motility and immune function are widely accepted as contributing factors to both conditions, and the brain-gut axis plays a key role in these processes. Traditional Chinese Medicine (TCM) employs a holistic approach to treatment, considers spleen and stomach impairments and liver abnormality the main pathogenesis of these two diseases, and offers a unique therapeutic strategy that targets these interconnected pathways. Clinical evidence shows the great potential of TCM in treating FGIDs and IBD. This study presents a systematic description of the pathological mechanisms of FGIDs and IBD in the context of the brain-gut axis, discusses clinical and preclinical studies on TCM and acupuncture for the treatment of these diseases, and summarizes TCM targets and pathways for the treatment of FGIDs and IBD, integrating ancient wisdom with contemporary biomedical insights. The alleviating effects of TCM on FGID and IBD symptoms are mainly mediated through the modulation of intestinal immunity and inflammation, sensory transmission, neuroendocrine-immune network, and microbiota and their metabolism through brain-gut axis mechanisms. TCM may be a promising treatment option in controlling FGIDs and IBD; however, further high-quality research is required. This review provides a reference for an in-depth exploration of the interventional effects and mechanisms of TCM in FGIDs and IBD, underscoring TCM's potential to recalibrate the dysregulated brain-gut axis in FGIDs and IBD.

Acupuncture and moxibustion intervention in functional dyspepsia: Gastric and duodenal regulation

Functional dyspepsia (FD) is a brain-gut interaction disorder located in the stomach and duodenum, which has complex pathophysiological mechanisms, and there is no effective treatment for FD. Acupuncture and moxibustion have been proven to have definite and significant efficacy on FD. Focusing on the affected area and combined with the potential pathophysiology of FD, here we discuss the possible mechanisms of acupuncture and moxibustion in treating FD to guide future clinical and experimental research. We argue that the pathological causes of FD can be roughly divided into gastrointestinal dysfunction, duodenal low-grade inflammation, visceral hypersensitivity, and duodenal intestinal barrier and microbial imbalance. Correspondingly, the possible mechanisms of acupuncture and moxibustion in treating FD are elucidated from the perspective of how they improve gastric accommodation, regulate gastrointestinal motility, reduce gastric visceral sensitivity, regulate eosinophil-mast cell axis, inhibit low-grade inflammatory responses, and possibly regulate intestinal microbial homeostasis and duodenal barrier function through the microbiota-gut-brain axis. Although some evidence is still lacking, acupuncture remains a promising treatment for FD. In the future, it is necessary to conduct additional clinical and experimental research on acupuncture and moxibustion in treating FD to further explore their effects and mechanisms.

Royal jelly a promising therapeutic intervention and functional food supplement: A systematic review

Royal jelly (RJ), a secretion produced by honeybees, has garnered significant interest for its potential as a therapeutic intervention and functional food supplement. This systematic review aims to synthesize current research on the health benefits, bioactive components, and mechanisms of action of RJ. Comprehensive literature searches were conducted across multiple databases, including PubMed, Scopus, and Web of Science, focusing on studies published from 2000 to 2024 (April). Findings indicate that RJ exhibits a wide range of pharmacological activities, including anti-inflammatory, antioxidant, antimicrobial, and anti-aging effects. Beneficial biological properties of RJ might be due to the presence of flavonoids proteins, peptides, fatty acids. Both preclinical and clinical studies have reported that RJ improves the immune function such as wound healing, and also decreases the severity of chronic diseases including diabetes and cardiovascular disorders. The molecular mechanisms underlying these effects involve modulation of signalling pathways such as NF-κB, MAPK, and AMPK. Despite promising results, the review identifies several gaps in the current knowledge, including the need for standardized dosing regimens and long-term safety assessments. Furthermore, variations in RJ composition due to geographic and botanical factors necessitate more rigorous quality control measures. This review underscores the potential of RJ as a multifunctional therapeutic agent and highlights the necessity for further well designed studies to fully elucidate its health benefits and optimize its use as a functional food supplement.

Da-Jian-Zhong decoction alleviates diarrhea-predominant irritable bowel syndrome via modulation of gut microbiota and Th17/Treg balance

ETHNOPHARMACOLOGICAL RELEVANCE

Da-Jian-Zhong decoction (DJZD) is a herbal formula clinically used for abdominal pain and diarrhea induced by spleen-Yang deficiency syndrome. Recently, treatment of diarrhea-predominant irritable bowel syndrome (IBS-D) with DJZD has received increasing attention, but the underlying mechanism of action remains elusive.

AIM OF THE STUDY

We aimed to evaluate the therapeutic effect of DJZD on IBS-D rats and to elucidate the underlying mechanisms.

MATERIALS AND METHODS

An IBS-D rats model was constructed using a two-factor superposition method of neonatal maternal separation and Senna folium aqueous extract lavage. Moreover, the effect of DJZD was evaluated based on the body weight, rectal temperature, abdominal withdrawal reflex (AWR), and Bristol stool scale score (BSS). The factors that regulate the DJZD effects on IBS-D were estimated using whole microbial genome, transcriptome sequencing (RNA-Seq), flow cytometry, and quantitative reverse transcription polymerase chain reaction (RT-qPCR) analyses.

RESULTS

We found that DJZD alleviated the symptoms of IBS-D rats, with the low-dose (2.4 g/kg) as the better ones, as shown by the higher body weight and lower AWR score and BSS. At the phylum level, the relative abundance of Bacteroidetes was obviously increased, and at the genus level, Lactobacillus and Parabacteroides were increased, while that of Firmicutes_bacterium_424 and Ruminococcus gnavus was decreased in DJZD group. Furthermore, the significantly enriched GO terms after treatment with DJZD mainly included the immune response, positive regulation of activated T cell proliferation, and positive regulation of interleukin-17 (IL-17) production. Importantly, flow cytometry analysis further revealed that the T helper cell type 17/regulatory T cell (Th17/Treg) balance contributed to the DJZD-induced alleviation of IBS-D symptoms, as DJZD downregulated Th17/Treg ratio and Th17 cell-related cytokines IL-17 and IL-6 levels in the colon.

CONCLUSIONS

These results demonstrated that DJZD has a good therapeutic effect on IBS-D rats, probably by maintaining the homeostasis of gut microbiota and regulating Th17/Treg balance and its related inflammatory factors.

Systematic analysis of levels of evidence supporting Chinese clinical practice guidelines for gastrointestinal disease

BACKGROUND

Clinical practice guidelines (CPGs) inform healthcare decisions and improve patient care. However, an evaluation of guidelines on gastrointestinal diseases (GIDs) is lacking. This study aimed to systematically analyze the level of evidence (LOE) supporting Chinese CPGs for GIDs.

METHODS

CPGs for GIDs were identified by systematically searching major databases. Data on LOEs and classes of recommendations (CORs) were extracted. According to the Grades of Recommendation, Assessment, Development, and Evaluation system, LOEs were categorized as high, moderate, low, or very low, whereas CORs were classified as strong or weak. Statistical analyses were conducted to determine the distribution of LOEs and CORs across different subtopics and assess changes in evidence quality over time.

FINDINGS

Only 27.9% of these recommendations were supported by a high LOE, whereas approximately 70% were strong recommendations. There was a significant disparity among different subtopics in the proportion of strong recommendations supported by a high LOE. The number of guidelines has increased in the past 5 years, but there has been a concomitant decline in the proportion of recommendations supported by a high LOE.

CONCLUSIONS

There is a general lack of high-quality evidence supporting Chinese CPGs for GIDs, and there are inconsistencies in strong recommendations that have not improved. This study identified areas requiring further research, emphasizing the need to bridge these gaps and promote the conduct of high-quality clinical trials.

FUNDING

This study was supported by the National Key R&D Program of China (2022YFC2503604 and 2022YFC2503605) and Special Topics in Military Health Care (22BJZ25).

Unraveling the role of ADAMs in clinical heterogeneity and the immune microenvironment of hepatocellular carcinoma: insights from single-cell, spatial transcriptomics, and bulk RNA sequencing

Background

Hepatocellular carcinoma (HCC) is a prevalent and heterogeneous tumor with limited treatment options and unfavorable prognosis. The crucial role of a disintegrin and metalloprotease (ADAM) gene family in the tumor microenvironment of HCC remains unclear.

Methods

This study employed a novel multi-omics integration strategy to investigate the potential roles of ADAM family signals in HCC. A series of single-cell and spatial omics algorithms were utilized to uncover the molecular characteristics of ADAM family genes within HCC. The GSVA package was utilized to compute the scores for ADAM family signals, subsequently stratified into three categories: high, medium, and low ADAM signal levels through unsupervised clustering. Furthermore, we developed and rigorously validated an innovative and robust clinical prognosis assessment model by employing 99 mainstream machine learning algorithms in conjunction with co-expression feature spectra of ADAM family genes. To validate our findings, we conducted PCR and IHC experiments to confirm differential expression patterns within the ADAM family genes.

Results

Gene signals from the ADAM family were notably abundant in endothelial cells, liver cells, and monocyte macrophages. Single-cell sequencing and spatial transcriptomics analyses have both revealed the molecular heterogeneity of the ADAM gene family, further emphasizing its significant impact on the development and progression of HCC. In HCC tissues, the expression levels of ADAM9, ADAM10, ADAM15, and ADAM17 were markedly elevated. Elevated ADAM family signal scores were linked to adverse clinical outcomes and disruptions in the immune microenvironment and metabolic reprogramming. An ADAM prognosis signal, developed through the utilization of 99 machine learning algorithms, could accurately forecast the survival duration of HCC, achieving an AUC value of approximately 0.9.

Conclusions

This study represented the inaugural report on the deleterious impact and prognostic significance of ADAM family signals within the tumor microenvironment of HCC.

A Starch- and Sucrose-Reduced Diet Has Similar Efficiency as Low FODMAP in IBS-A Randomized Non-Inferiority Study

A diet with low content of fermentable oligo-, di-, and monosaccharides and polyols (FODMAP) is established treatment for irritable bowel syndrome (IBS), with well-documented efficiency. A starch- and sucrose-reduced diet (SSRD) has shown similar promising effects. The primary aim of this randomized, non-inferiority study was to test SSRD against low FODMAP and compare the responder rates (RR = ∆Total IBS-SSS ≥ -50) to a 4-week dietary intervention of either diet. Secondary aims were to estimate responders of ≥100 score and 50% reduction; effects on extraintestinal symptoms; saturation; sugar craving; anthropometric parameters; and blood pressure. 155 IBS patients were randomized to SSRD (n = 77) or low FODMAP (n = 78) for 4 weeks, with a follow-up 5 months later without food restrictions. The questionnaires Rome IV, IBS-severity scoring system (IBS-SSS), and visual analog scale for IBS (VAS-IBS) were completed at baseline and after 2 and 4 weeks and 6 months. Weight, height, waist circumference, and blood pressures were measured. Comparisons were made within the groups and between changes in the two groups. There were no differences between groups at baseline. The responder rate of SSRD was non-inferior compared with low FODMAPs at week 2 (79.2% vs. 73.1%; p = 0.661;95% confidence interval (CI) = -20-7.2) and week 4 (79.2% vs. 78.2%; p = 1.000;95%CI = -14-12). Responder rate was still high when defined stricter. All gastrointestinal and extraintestinal symptoms were equally improved (p < 0.001 in most variables). SSRD rendered greater reductions in weight (p = 0.006), body mass index (BMI) (p = 0.005), and sugar craving (p = 0.05), whereas waist circumference and blood pressure were equally decreased. Weight and BMI were regained at follow-up. In the SSRD group, responders at 6 months still had lowered weight (-0.7 (-2.5-0.1) vs. 0.2 (-0.7-2.2) kg; p = 0.005) and BMI (-0.25 (-0.85-0.03) vs. 0.07 (-0.35-0.77) kg/m2; p = 0.009) compared with baseline in contrast to non-responders. Those who had tested both diets preferred SSRD (p = 0.032). In conclusion, a 4-week SSRD intervention was non-inferior to low FODMAP regarding responder rates of gastrointestinal IBS symptoms. Furthermore, strong reductions of extraintestinal symptoms were found in both groups, whereas reductions in weight, BMI, and sugar craving were most pronounced following SSRD.