Diagnosis and treatment of irritable bowel syndrome with predominant constipation in the primary-care setting: focus on linaclotide

The Vibrating Capsule: Safety and Tolerability in Patients With Chronic Idiopathic Constipation

BACKGROUND

Chronic idiopathic constipation (CIC) remains a significant problem globally with increasing estimates for disease burden. In a Phase 3 placebo-controlled trial, a novel treatment using the Vibrating Capsule was recently shown to be effective in treating patients with CIC. However, its safety and tolerability has not been described in detail.

METHODS

We analyzed safety data from six trials encompassing the development of the Vibrating Capsule, including, dose-ranging and pivotal studies. The incidence of adverse events, treatment discontinuation, tolerability and satisfaction were assessed.

KEY RESULTS

A total of 800 patients who took either an active Vibrating Capsule or a sham/placebo (non-vibrating) but similar capsule from 6 studies were included in this post hoc analysis. The most common adverse gastrointestinal events were bloating (2.9%), abdominal pain (2.9%), nausea (2.3%) and diarrhea (1.9%). A sensation of vibration was reported by 11.7% of patients. The adverse events rates were low, and investigators categorized most of them as unrelated to treatment. There were no serious adverse events such as retention of therapeutic capsules and no patient stopped therapy or withdrew due to adverse effects. The majority of patients (83%) found the system convenient, with an overall treatment satisfaction rate of 71%.

CONCLUSIONS AND INFERENCES

The Vibrating Capsule, a first in class treatment for CIC was found to be safe and well tolerated by patients in clinical trials. No patient discontinued treatment due to adverse events.

Review of the Patient Burden and Therapeutic Landscape of Irritable Bowel Syndrome with Constipation in the United States

Irritable bowel syndrome (IBS) is a common disorder of the gut-brain axis. IBS with constipation (IBS-C) accounts for approximately one-third of IBS cases and is associated with substantial burden of illness and decreased quality of life. This narrative review provides an overview of the current and upcoming treatment options and disease management for IBS-C from a US perspective and discusses the importance of the relationship between patient and health care provider in diagnosis and treatment. A positive diagnostic strategy for IBS-C is recommended, based on clinical history, physical examination, and minimal laboratory tests. An effective communication strategy between patients and health care professionals is essential to ensure early diagnosis and reduce both health care costs and overall disease burden. Treatment typically begins with lifestyle interventions and nonpharmacologic options, such as dietary interventions, fiber supplements, and osmotic laxatives. In patients with inadequate response to these therapies, 4 currently available therapies (lubiprostone, linaclotide, plecanatide, and tenapanor) approved by the US Food and Drug Administration may relieve IBS-C symptoms. These agents are generally well tolerated and efficacious in improving IBS-C symptoms, including constipation and abdominal pain. In patients with persistent abdominal pain and/or psychological symptoms, brain-gut behavioral therapy or neuromodulator therapy may be beneficial.

Acacia fiber or probiotic supplements to relieve gastrointestinal complaints in patients with constipation-predominant IBS: a 4-week randomized double-blinded placebo-controlled intervention trial

PURPOSE

To date, no adequate treatment for irritable bowel syndrome with predominant constipation complaints (IBS-C) is available. Fibers with prebiotic properties and probiotic compounds have shown promise in relieving IBS-C-related complaints. We aimed to determine the effects of a 4-week intervention with either an Acacia fiber (AF) with prebiotic properties or a probiotic Bifidobacterium Lactis (BLa80) supplement, compared to a control supplement, on stool pattern, IBS symptoms and Quality of Life (QoL), in IBS-C individuals.

METHODS

A parallel, double-blind, randomized controlled trial involving 180 subjects meeting the ROME IV criteria for IBS-C was conducted. Following a 4-week observation period, subjects received either AF (10 g), Probiotic BLa80 (4 g; 2 × 1011 CFU/g) or a maltodextrin placebo (10 g) daily for 4 weeks. Subjects reported daily information on stool pattern and gastrointestinal complaints. Before and after each 4-week period, questionnaires on symptom severity, constipation symptoms, anxiety and depression and QoL were completed. Stool mass was measured for 5-days before and after the intervention.

RESULTS

Stool frequency significantly improved in the AF and Probiotic BLa80 groups compared to placebo (P < 0.001, P = 0.02, respectively). Probiotic BLa80 showed a significant reduction in IBS symptom severity (P = 0.03), for AF a trend towards decreased constipation symptoms (PAC-SYM, P = 0.10) was observed. No significant changes in stool consistency, stool mass or QoL measures were observed between the AF and Probiotic BLa80 compared to placebo.

CONCLUSION

Daily dietary supplementation with Acacia fiber and probiotic supplements might help IBS-C patients by relieving IBS-related complaints compared to a placebo supplement.

REGISTRATION NUMBER OF CLINICAL TRIAL

The trial is registered at ClinicalTrials.gov: NCT04798417: Study Details | Nutrition to Relieve IBS Constipation | ClinicalTrials.gov.

Polycystic Ovary Syndrome and Irritable Bowel Syndrome: Is There a Common Pathway?

OBJECTIVE

Little is known about how polycystic ovary syndrome (PCOS) is linked to irritable bowel syndrome (IBS). This study aimed to review the existing literature regarding the association between PCOS or its symptoms and complications with IBS.

METHODS

In this review, studies that investigated the proposed cross-link between features of PCOS and IBS were included. This review collectively focused on recent findings on the mechanism and novel insight regarding the association between IBS and PCOS in future clinical practice. An electronic search of PubMed, Scopus, Epistemonikos, Cochrane Library and Google Scholar was performed. We did not restrict the study setting and publication date.

RESULTS

The existing evidence has not completely answered the question of whether there is an association between PCOS and IBS and vice versa. Six case-control studies (793 women with PCOS and 547 women in the control group) directly assessed the association between PCOS and IBS. The prevalence of IBS among women with PCOS in these studies has ranged from 10% to 52% compared with 5%-50% in control groups. Evidence suggested the common pathways may have contributed to the interaction between IBS and PCOS, including metabolic syndrome, sex hormone fluctuation, dysregulation of neurotransmitters, psychological problems and environmental and lifestyle factors. To date, it is still ambiguous which of the mentioned components largely contributes to the pathogenesis of both.

CONCLUSION

Although limited evidence has shown a higher prevalence of IBS in women with PCOS, there are several potential, direct and common indirect pathways contributing to the development of both IBS and PCOS.

The Use of Pictograms in the Evaluation of Functional Abdominal Pain Disorders in Children

OBJECTIVE

To evaluate whether the use of pictograms improves symptom evaluation for children with functional abdominal pain disorders (FAPDs).

STUDY DESIGN

This survey study was conducted in 2 academic centers and included patients aged 8-18 years visiting the outpatient clinic for FAPD symptom evaluation. Patients were randomized to fill out the questionnaire without or with accompanying pictograms to assess gastrointestinal symptoms. Afterwards, patients underwent clinical health assessment by the healthcare professional (HCP). Subsequently, the HCP filled out the same questionnaire without pictograms, while blinded to the questionnaire completed by the patient. Primary outcome was the level of agreement between identified symptoms as assessed by patients and HCP.

RESULTS

We included 144 children (questionnaire without accompanying pictograms [n = 82] and with accompanying pictograms [n = 62]). Overall agreements rates were not significantly different (without pictograms median, 70% vs with pictograms median, 70%). Accompanying pictograms did not significantly improve the assessment of abdominal pain symptoms. Accompanying pictograms were beneficial for concordance rates for nausea and vomiting symptoms (without pictograms median, 67% vs with pictograms median, 100%; P = .047). Subgroup analyses for children aged 8-12 years of age revealed similar results (concordance on the presence of nausea and vomiting without pictograms median, 67% vs with pictograms median, 100%; P = .015). Subgroup analyses for children ages 12-18 years showed no significant differences in concordance rates.

CONCLUSIONS

Pictograms do not seem to improve the assessment of FAPDs. However, the use of pictograms improves the evaluation of nausea and vomiting, especially for children aged 8-12 years. Therefore, HCPs could consider using pictograms in that setting during consultations.

Determination of Probiotics Prescription Indications in Patients with Irritable Bowel Syndrome (Materials of the Expert Council and Literature Review)

Aim. To review the main indications for probiotics prescription in patients with irritable bowel syndrome and to present the materials of an Expert Council, which was held on 18 March 2022 in Moscow.

Key points. Gut microbiota disturbance is an integral part of irritable bowel syndrome (IBS) pathogenesis. Changes of colonic microbiota composition are associated with its functional potential modification, which leads to an increasing of the pro-inflammatory immune response, as well as to an exacerbation of the disease symptoms and quality of life decreasing in patients with IBS. The novel coronavirus infection (COVID-19) is an independent risk factor for both exacerbation and onset of IBS, which predispose to increase IBS incidence. Correction of gut microbiota composition with probiotics seems to be a promising therapeutic target for IBS treatment optimizing. The optimal probiotic should be effective, safe, strain-specific, and its dose and duration of administration should be confirmed by the results of clinical studies. Some of the probiotics with proven efficacy in IBS are Alflorex® and Enterol®.

Conclusion. Prescription of certain probiotics in IBS is advisable to normalize the frequency and consistency of stools, relieve abdominal pain and bloating, as well as improve patients’ quality of life.

Emerging therapies in the management of Irritable Bowel Syndrome (IBS)

INTRODUCTION

Irritable bowel syndrome (IBS) is a common, symptom-based disorder of chronic abdominal pain and altered bowel habits. The pathogenesis of IBS is multifactorial, leading to the potential for the development of multiple, diverse treatment strategies. This mechanistic heterogeneity also leads to the realization that available therapies are only effective in a subset of IBS suffers. Current US Food and Drug Administration (FDA) approved therapies for IBS with diarrhea (IBS-D) and IBS with constipation (IBS-C) are reviewed. Limited symptom responses and side effect experiences lead to considerable patient dissatisfaction with currently available IBS treatments. Only a small percentage of IBS patients are on prescription therapies underscoring the potential market and need for additional therapeutic options.

AREAS COVERED

: Expanding on currently available therapies, the serotonergic and endogenous opioid receptor systems continue to be a focus of future IBS treatment development. Additional novel emerging therapies include the endogenous cannabinoid system, bile acid secretion and sequestration, and exploit our enhanced understanding of visceral sensory signaling and intestinal secretomotor function.

EXPERT OPINION

While challenges remain for the future development of IBS therapies, the diverse etiologies underlying the disorder present an opportunity for novel therapies. Hence, great potential is anticipated for future IBS treatment options.

Gut dysbacteriosis and intestinal disease: mechanism and treatment

The gut microbiome functions like an endocrine organ, generating bioactive metabolites, enzymes or small molecules that can impact host physiology. Gut dysbacteriosis is associated with many intestinal diseases including (but not limited to) inflammatory bowel disease, primary sclerosing cholangitis-IBD, irritable bowel syndrome, chronic constipation, osmotic diarrhoea and colorectal cancer. The potential pathogenic mechanism of gut dysbacteriosis associated with intestinal diseases includes the alteration of composition of gut microbiota as well as the gut microbiota-derived signalling molecules. The many correlations between the latter and the susceptibility for intestinal diseases has placed a spotlight on the gut microbiome as a potential novel target for therapeutics. Currently, faecal microbial transplantation, dietary interventions, use of probiotics, prebiotics and drugs are the major therapeutic tools utilized to impact dysbacteriosis and associated intestinal diseases. In this review, we systematically summarized the role of intestinal microbiome in the occurrence and development of intestinal diseases. The potential mechanism of the complex interplay between gut dysbacteriosis and intestinal diseases, and the treatment methods are also highlighted.

Mechanical Stimuli Affect Escherichia coli Heat-Stable Enterotoxin-Cyclic GMP Signaling in a Human Enteroid Intestine-Chip Model

Modeling host-pathogen interactions with human intestinal epithelia using enteroid monolayers on permeable supports (such as Transwells) represents an alternative to animal studies or use of colon cancer-derived cell lines. However, the static monolayer model does not expose epithelial cells to mechanical forces normally present in the intestine, including luminal flow and serosal blood flow (shear force) or peristaltic forces. To determine the contribution of mechanical forces in the functional response of human small intestine to a virulence factor of a pathogenic intestinal bacterium, human jejunal enteroids were cultured as monolayers in microengineered fluidic-based Organ-Chips (Intestine-Chips) exposed to enterotoxigenic Escherichia coli heat-stable enterotoxin A (ST) and evaluated under conditions of static fluid, apical and basolateral flow, and flow plus repetitive stretch. Application of flow increased epithelial cell height and apical and basolateral secretion of cyclic GMP (cGMP) under baseline, unstimulated conditions. Addition of ST under flow conditions increased apical and basolateral secretion of cGMP relative to the level under static conditions but did not enhance intracellular cGMP accumulation. Cyclic stretch did not have any significant effect beyond that contributed by flow. This study demonstrates that fluid flow application initiates changes in intestinal epithelial cell characteristics relative to those of static culture conditions under both baseline conditions and with exposure to ST enterotoxin and suggests that further investigations of the application of these mechanical forces will provide insights into physiology and pathophysiology that more closely resemble intact intestine than study under static conditions.

European society of neurogastroenterology and motility guidelines on functional constipation in adults

INTRODUCTION

Chronic constipation is a common disorder with a reported prevalence ranging from 3% to 27% in the general population. Several management strategies, including diagnostic tests, empiric treatments, and specific treatments, have been developed. Our aim was to develop European guidelines for the clinical management of constipation.

DESIGN

After a thorough review of the literature by experts in relevant fields, including gastroenterologists, surgeons, general practitioners, radiologists, and experts in gastrointestinal motility testing from various European countries, a Delphi consensus process was used to produce statements and practical algorithms for the management of chronic constipation.

KEY RESULTS

Seventy-three final statements were agreed upon after the Delphi process. The level of evidence for most statements was low or very low. A high level of evidence was agreed only for anorectal manometry as a comprehensive evaluation of anorectal function and for treatment with osmotic laxatives, especially polyethylene glycol, the prokinetic drug prucalopride, secretagogues, such as linaclotide and lubiprostone and PAMORAs for the treatment of opioid-induced constipation. However, the level of agreement between the authors was good for most statements (80% or more of the authors). The greatest disagreement was related to the surgical management of constipation.

CONCLUSIONS AND INFERENCES

European guidelines on chronic constipation, with recommendations and algorithms, were developed by experts. Despite the high level of agreement between the different experts, the level of scientific evidence for most recommendations was low, highlighting the need for future research to increase the evidence and improve treatment outcomes in these patients.

Irritable Bowel Syndrome between Molecular Approach and Clinical Expertise-Searching for Gap Fillers in the Oxidative Stress Way of Thinking

Irritable bowel syndrome (IBS) remains to date an intriguing functional gastrointestinal disorder. Recent studies described a multitude of exogenous factors that work together in IBS, gradually impairing intestinal lining cellular metabolism, including oxidative status balance, with or without a genetic background. Although the current biomarkers support the differentiation between IBS subtypes and other functional gastrointestinal disorder, they are mostly non-specific, referring to clinical, biochemical, and inflammatory imbalances. Since IBS could be also the result of deficient signaling pathways involving both gastrointestinal secretion and neuro-vegetative stimulation, IBS makes no exception from the oxidative hypothesis in the pathological mechanisms. Regarding the oxidative stress implication in IBS, the previous research efforts showed controversial results, with some animal models and patient studies reporting clear oxidative imbalance both on systemic and local levels, but still with no concrete evidence to point to a direct correlation between oxidative stress and IBS. Additionally, it seems that a major role could be also attributed to gut microbiota and their ability to shape our bodies and behaviors. Moreover, the genetic features study in IBS patients showed that several genetic similarities point to a possible correlation of IBS with affective spectrum disorders. Thus, we focus here the discussion on the assumption that IBS could in fact be more likely a stress-related disorder rather than a gastrointestinal one.

Cognitive impairment in Irritable Bowel Syndrome (IBS): A systematic review

BACKGROUND

Irritable Bowel Syndrome (IBS) is a common functional gastrointestinal disorder which is characterized by altered bowel habits. A growing number of studies investigate the association between IBS and cognitive impairments. Current studies report conflicting results regarding cognitive impairment in IBS patients. We therefore conducted the first systematic review to examine the association between IBS and cognitive impairment and identify the types of cognitive domain involved.

STUDY DESIGN

Eight databases (MEDLINE, CINAHL, EMBASE, Cochrane Library, PsycINFO, ScienceDirect, China National Knowledge Infrastructure (CNKI), and Chinese Biomedical Literature Database (CBM)) were searched from the inception date up till 15 February 2018. Observational studies published in English or Chinese were independently appraised, and data was extracted, by two reviewers using the Joanna Briggs Institute (JBI) Critical Appraisal Checklist for Analytical Cross-Sectional Studies. The findings were synthesized using a narrative approach.

RESULTS

Twelve studies met the inclusion criteria. Our findings suggested that IBS patients exhibited attentional bias towards GI sensation words and emotionally negative words. There was insufficient evidence of evidences to show that IBS patients had cognitive deficits in memory, intelligence, executive functions and general cognitive functions. A number of limitations were identified, including small sample, limited cognitive domain inclusion, lack of study details, and management of confounding variables.

CONCLUSION

There is evidence of attentional bias in individuals with IBS; the evidence on cognitive impairment was either inconclusive or insufficient in other cognitive domains. Further studies are needed to confirm prevalence rates and examine potential mechanisms.

Treatment failure in children diagnosed with constipation in a paediatric emergency department in relation to Rome III criteria

Objective

To determine if treatment failure varies based on ROME III classification and adherence to guideline congruent therapy among children diagnosed in an emergency department with functional constipation.

Methods

Children aged 1 month to 18 years who were diagnosed with constipation in a paediatric emergency department underwent chart review and 7-day phone follow-up to complete the ROME III questionnaire, confirm treatments administered, and assess treatment failure. Participants were classified according to the ROME III criteria as having functional constipation (FC) or irritable bowel syndrome - constipation (IBS-C) subtype. The primary outcome was treatment failure defined as ≥ 2 of the following: 1) presenting symptom persistence; 2) < 1 bowel movement every other day; 3) pain/difficulty passing stools; and 4) abdominal pain between bowel movements.

Results

Five hundred and thirteen children completed follow-up; 40% (204/513) had FC, 23% (118/513) IBS-C, and 37% (191/513) did not meet either criteria. Treatment failure rates in children who received guideline congruent treatment were 28% (38/135) among those classified as FC and 43% (37/86) among those with IBS-C; P=0.02, a difference of 15% (95% confidence interval [CI]: 0.02, 0.27). On regression analysis, ROME III classification was not an independent predictor of treatment failure (odds ratio [OR]: 1.56 [95% CI: 0.97, 2.51]). At 7-day follow up, pain in between bowel movements was present in 22% (44/204) in FC patients versus 45% (53/118) of IBS-C patients; P=0.001.

Conclusions

Treatment failure rates in children who receive guideline congruent therapy are higher among those with IBS-C, however, after adjustment for known confounders the relationship was not statistically significant.

Declining Rates of Referral for Irritable Bowel Syndrome Without Constipation at a Tertiary Care Center

BACKGROUND

Irritable bowel syndrome (IBS) is a common chronic disorder of the gastrointestinal tract. Several treatments have been developed, including rifaximin for the treatment of IBS without constipation (non-IBS-C), but no studies have evaluated the effect of these therapies on patient referral rates to tertiary care gastroenterology clinics.

AIM

To assess referral patterns for IBS patients at a tertiary motility clinic over a 10-year period.

METHODS

Data from consecutive patients referred to the clinic during 2006-2016 were analyzed. Trends in the proportion of referrals and prior rifaximin use in IBS-C versus non-IBS-C groups were compared.

RESULTS

A total of 814 adult patients were referred to a single physician panel for IBS-related symptoms. Of these, 776 were included in the study [528 females (68%), average age 45.7 ± 15.9 years), comprising 431 IBS-C (55.5%) and 345 non-IBS-C (44.5%) patients. The proportion of non-IBS-C referrals declined significantly from 53.0% in 2006 to 27.3% in 2016 (Chi-square, p < 0.0001, Cochran-Armitage trend test p = 0.0001), and the proportion of IBS-C referrals increased significantly from 46.9% in 2006 to 72.7% in 2016 (Chi-square, p < 0.0001, Cochran-Armitage trend test p = 0.0004). Non-IBS-C referrals with prior rifaximin use significantly increased from 22.7% in 2006 to 66.7% in 2016 (Cochran-Armitage trend test, p = 0.008).

CONCLUSIONS

The results indicate a significantly declining tertiary care referral rate for non-IBS-C over the past decade. While not directly linked, there has been an increase in rifaximin use in the same population during the same time interval.

Sex-Gender Differences in Irritable Bowel Syndrome

Because of the sex-gender differences that are shown in a diversity of physiological and psychological factors, it can be speculated that the clinical presentation of symptoms as well as treatment strategies in women and men with irritable bowel syndrome (IBS) may differ. Studies have revealed that IBS is more common in women than men. As for the IBS subtype, IBS with constipation is significantly more prevalent among women than men. Sex hormones and gender differences may play important roles in the pathophysiology of IBS. However, its pathophysiologic mechanisms still remain largely unknown, and therapeutic implications are limited. Moreover, women IBS patients have been reported to feel more fatigue, depression, anxiety, and lower quality of life than men IBS patients. Furthermore, there has been evidence of differences in the appropriate treatment efficacy to IBS in men and women, although relatively few men are enrolled in most relevant clinical trials. A more sex-gender-oriented approach in the medical care setting could improve understanding of heterogeneous patients suffering from IBS. An individualized and multicomponent approach including sex and gender issues might help improve the treatment of IBS.

The Guanylate Cyclase C-cGMP Signaling Axis Opposes Intestinal Epithelial Injury and Neoplasia

Guanylate cyclase C (GUCY2C) is a transmembrane receptor expressed on the luminal aspect of the intestinal epithelium. Its ligands include bacterial heat-stable enterotoxins responsible for traveler's diarrhea, the endogenous peptide hormones uroguanylin and guanylin, and the synthetic agents, linaclotide, plecanatide, and dolcanatide. Ligand-activated GUCY2C catalyzes the synthesis of intracellular cyclic GMP (cGMP), initiating signaling cascades underlying homeostasis of the intestinal epithelium. Mouse models of GUCY2C ablation, and recently, human populations harboring GUCY2C mutations, have revealed the diverse contributions of this signaling axis to epithelial health, including regulating fluid secretion, microbiome composition, intestinal barrier integrity, epithelial renewal, cell cycle progression, responses to DNA damage, epithelial-mesenchymal cross-talk, cell migration, and cellular metabolic status. Because of these wide-ranging roles, dysregulation of the GUCY2C-cGMP signaling axis has been implicated in the pathogenesis of bowel transit disorders, inflammatory bowel disease, and colorectal cancer. This review explores the current understanding of cGMP signaling in the intestinal epithelium and mechanisms by which it opposes intestinal injury. Particular focus will be applied to its emerging role in tumor suppression. In colorectal tumors, endogenous GUCY2C ligand expression is lost by a yet undefined mechanism conserved in mice and humans. Further, reconstitution of GUCY2C signaling through genetic or oral ligand replacement opposes tumorigenesis in mice. Taken together, these findings suggest an intriguing hypothesis that colorectal cancer arises in a microenvironment of functional GUCY2C inactivation, which can be repaired by oral ligand replacement. Hence, the GUCY2C signaling axis represents a novel therapeutic target for preventing colorectal cancer.

Large bowel obstruction in a 27-year-old woman caused by a sigmoid faecal bolus

A 27-year-old woman presented to the emergency department with a 24-hour history of severe left iliac fossa pain associated with vomiting. She reported a history of ovarian cysts and was provisionally diagnosed with a ruptured ovarian cyst and admitted under the obstetrics and gynaecology team for further investigation. 24 hours later, she became haemodynamically unstable with increasing abdominal distention and developed a metabolic acidosis. A CT scan revealed large bowel obstruction (LBO) secondary to a faecal bolus in the sigmoid colon with appearances suggestive of adult-onset Hirschsprung's disease. She underwent an emergency laparotomy and decompressive transverse colotomy and was admitted to the intensive care unit overnight. After discharge, she presented again with small bowel obstruction (SBO) which resolved with conservative management. A follow-up colonoscopy and biopsies showed no anatomical abnormalities to account for the LBO and were inconclusive for Hirschsprung's disease.