The Science, Evidence, and Practice of Dietary Interventions in Irritable Bowel Syndrome

Microbiota modulation in disorders of gut-brain interaction

Disorders of gut-brain interaction (DGBI) are common chronic conditions characterized by persistent and recurring gastrointestinal symptoms triggered by several pathophysiological factors, including an altered gut microbiota. The most common DGBI are irritable bowel syndrome (IBS), functional constipation (FC) and functional dyspepsia (FD). Recently, a deep understanding of the role of the gut microbiota in these diseases was possible due to multi-omics methods capable to provide a comprehensive assessment. Most of the therapies recommended for these patients, can modulate the gut microbiota such as diet, prebiotics, probiotics and non-absorbable antibiotics, which were shown to be safe and effective. Since patients complain symptoms after food ingestion, diet represents the first line therapeutic approach. Avoiding dietary fat and fermentable oligosaccharides, disaccharides, monosaccharides, and polyols, and increasing the number of soluble fibers represent the therapeutic choices for FD, IBS and FC respectively. Probiotics, as a category, have been employed with good results in all the abovementioned DGBI. Rifaximin has been shown to be useful in the context of bowel related disorders, although a recent trial showed positive results for FD. Fecal microbiota transplantation has been tested for IBS and FC with promising results. In this review, we will briefly summarize the current understanding on dysbiosis and discuss microbiota modulation strategies to treat patients with DGBI.

Supplementation With Bifidobacterium and Symptomatic Control in Irritable Bowel Syndrome: An Evidence-Based Review

Irritable bowel syndrome (IBS) is a functional gastrointestinal disorder, with a global prevalence of around 11%. Family doctors should be aware of the diagnosis and treatment of this pathology. The benefit of using probiotics is questionable. The purpose of this review is to establish the evidence of the association between Bifidobacterium supplementation and symptomatic control in patients with IBS. The research was conducted using the National Guideline Clearinghouse, National Electronic Library for Health of the British NHS, Canadian Medical Association Practice Guidelines InfoBase, Cochrane Library, Database of Abstracts of Reviews of Effectiveness, Bandolier, Evidence-Based Medicine Online, and PubMed. Articles published between March 2017 and March 2022 in humans and written in Portuguese, Spanish, and English using the terms IBS and Bifidobacterium were included. To stratify the level of evidence (LOE), the Strength of Recommendation Taxonomy (SORT), from the American Academy of Family Physicians, was used. Thirty-seven articles were found corresponding to the search terms, and a total of seven articles were selected. Three clinical trials and a simple review have demonstrated improvement in symptoms, although further studies are needed. The guideline and the systematic review did not demonstrate superiority in symptomatic relief when compared to other species of probiotics. The meta-analysis did not show the efficacy of the isolated use of Bifidobacterium. The evidence of an association between supplementation with Bifidobacterium and symptomatic control in patients with IBS is not clear. Some studies seem to demonstrate benefits in improving symptoms (SORT C).

Constipation-Predominant Irritable Bowel Syndrome (IBS-C): Effects of Different Nutritional Patterns on Intestinal Dysbiosis and Symptoms

Irritable bowel syndrome (IBS) is a chronic functional gastrointestinal disorder characterized by abdominal pain associated with defecation or a change in bowel habits. The pathogenesis of IBS is not completely clear, but it is known to be multifactorial and complex. Endogenous and exogenous factors such as abnormal GI motility, low-grade inflammation, increased epithelial permeability and visceral hypersensitivity, but diet and psychosocial aspects are also recognized as important actors. Furthermore, the interaction between diet and gut microbiota has gained interest as a potential contributor to the pathophysiology of IBS. To date, there is no specific diet for IBS with constipation (IBS-C); however, many studies show that fiber intake, especially soluble fiber such as inulin, could have a positive effect on symptoms. This review aims to evaluate the effects of some nutritional components such as fibers but also functional foods, prebiotics, probiotics and symbiotics on symptoms and microbiota in IBS-C subjects.

Fermentable Oligo-, Di-, and Mono-Saccharides and Polyols (FODMAPs) Consumption and Irritable Bowel Syndrome in the French NutriNet-Santé Cohort

(1) Background: Specific foods, and more particularly, fermentable oligo-, di-, and mono-saccharides and polyols (FODMAPs) are often considered as triggers of digestive symptoms in Irritable Bowel Syndrome (IBS). Our aim was to study FODMAP consumption in controls and IBS participants in a large French population-based cohort; (2) Methods: Participants from the NutriNet-Santé cohort study completed the Rome IV and IBS-SSS questionnaire in a cross sectional study. Among them, 27,949 eligible participants had previously completed three 24-h recalls as well as anthropometrics, socio-demographical and lifestyle data. Total FODMAP intake (in g/day) was computed using a specific composition table. The association between FODMAPs and IBS was estimated through multivariable logistic regression models; (3) Results: Included participants were mainly women (75.4%) and the mean age was 43.4 ± 14.1 years. FODMAPs accounted for a mean daily intake of 19.4 ± 9.5 g/day. Overall 1295 participants (4.6%) were identified with an IBS. After adjusting for confounding factors, IBS participants had lower intakes in FODMAPs than non-IBS ones (aOR: 0.88, 95% CI: 0.82–0.95, p-value: 0.001). IBS severity was associated with more frequent low FODMAP intakes (<9 g/day); (4) Conclusions: Participants tended to consume 19 g of FODMAPs per day, but slightly less for IBS participants than for controls. In IBS participants, higher severity was associated with lower intakes.

Feasibility of a low FODMAPs diet without initial dietician intervention in the management of patients with irritable bowel syndrome: a prospective study

BACKGROUND AND AIMS

Efficiency of a low FODMAPs diet (LFD) to relieve symptoms in patients with irritable bowel syndrome (IBS) has been proved in several studies. Our study aimed to evaluate the management of IBS-patients when explanations about LFD are given by the physician without dietician intervention.

PATIENTS AND METHODS

Patients with IBS were evaluated prospectively after explanations about the LFD were given with the help of a leaflet. A first questionnaire evaluating trigger foods and diet acceptability was submitted to the patient after the consultation. Six weeks later, a second questionnaire evaluated patient's understanding and adherence to the diet, the evolution of symptoms, and the need for a specific dietetic support.

RESULTS

Thirty-five patients were included (69% female; mean age 45±15). Seventy-four percent of the patients thought that their symptoms were related to food ingestion, and 97% were ready to go on a diet to improve their symptoms. During the second visit, 91% of the patients reported understanding correctly the explanations, 52% followed LFD regularly, 28% sometimes and 20% did not follow LFD at all or barely. Multiple non-adherence factors were reported. All symptoms, except constipation, decreased significantly six weeks after starting LFD. Finally, 77% of the patients reported satisfaction with care and 69% were willing to be supported by a dietician.

CONCLUSIONS

Most IBS patients understood explanations given by GI physicians, but low compliance to the diet and a wish for dietician support was highlighted, suggesting that a dietician intervention should be scheduled when LFD is implemented.

Ayurvedic vs. Conventional Nutritional Therapy Including Low-FODMAP Diet for Patients With Irritable Bowel Syndrome-A Randomized Controlled Trial

Aims: To compare the effects of Ayurvedic and conventional nutritional therapy in patients with irritable bowel syndrome (IBS).

Methods: Sixty-nine patients with IBS were randomized to Ayurvedic (n = 35) or conventional nutritional therapy according to the recommendations of the German Nutrition Society including the low-FODMAP diet (n = 34). Study visits took place at baseline and after 1, 3, and 6 months. The primary outcome was IBS symptom severity (IBS-SSS) after 3 months; secondary outcomes included stress (CPSS), anxiety and depression (HADS), well-being (WHO-5) and IBS-specific quality of life (IBS-QOL). A repeated measures general linear model (GLM) for intent-to-treat-analyses was applied in this explorative study.

Results: After 3 months, estimated marginal means for IBS-SSS reductions were 123.8 [95% confidence interval (95% CI) = 92.8–154.9; p < 0.001] in the Ayurvedic and 72.7 (95% CI = 38.8–106.7; p < 0.001) in the conventional group. The IBS-SSS reduction was significantly higher in the Ayurveda group compared to the conventional therapy group (estimated marginal mean = 51.1; 95% CI = 3.8–98.5; p = 0.035) and clinically meaningful. Sixty-eight percentage of the variance in IBS-SSS reduction after 3 months can be explained by treatment, 6.5% by patients' expectations for their therapies and 23.4% by IBS-SSS at pre-intervention. Both therapies are equivalent in their contribution to the outcome variance. The higher the IBS-SSS score at pre-intervention and the larger the patients' expectations, the greater the IBS-SSS reduction. There were no significant group differences in any secondary outcome measures. No serious adverse events occurred in either group.

Conclusion: Patients with IBS seem to benefit significantly from Ayurvedic or conventional nutritional therapy. The results warrant further studies with longer-term follow-ups and larger sample sizes.

Clinical Trial Registration:https://clinicaltrials.gov/ct2/show/NCT03019861, identifier: NCT03019861.

Diarrhea Predominant-Irritable Bowel Syndrome (IBS-D): Effects of Different Nutritional Patterns on Intestinal Dysbiosis and Symptoms

Irritable Bowel Syndrome (IBS) is a chronic functional gastrointestinal disorder characterized by abdominal pain associated with defecation or a change in bowel habits. Gut microbiota, which acts as a real organ with well-defined functions, is in a mutualistic relationship with the host, harvesting additional energy and nutrients from the diet and protecting the host from pathogens; specific alterations in its composition seem to play a crucial role in IBS pathophysiology. It is well known that diet can significantly modulate the intestinal microbiota profile but it is less known how different nutritional approach effective in IBS patients, such as the low-FODMAP diet, could be responsible of intestinal microbiota changes, thus influencing the presence of gastrointestinal (GI) symptoms. The aim of this review was to explore the effects of different nutritional protocols (e.g., traditional nutritional advice, low-FODMAP diet, gluten-free diet, etc.) on IBS-D symptoms and on intestinal microbiota variations in both IBS-D patients and healthy subjects. To date, an ideal nutritional protocol does not exist for IBS-D patients but it seems crucial to consider the effect of the different nutritional approaches on the intestinal microbiota composition to better define an efficient strategy to manage this functional disorder.

Management of irritable bowel syndrome with diarrhea: focus on eluxadoline

OBJECTIVE

We sought to summarize current recommendations for the diagnosis of diarrhea-predominant irritable bowel syndrome (IBS-D) and describe available management options, highlighting a newer US Food and Drug Administration (FDA)-approved agent, eluxadoline.

METHODS

Literature on IBS-D was assessed up to January 2020 using PubMed, with key search terms including "IBS-D diagnosis", "IBS-D management", and "eluxadoline".

RESULTS

IBS is a common gastrointestinal disorder affecting up to 14% of US adults and is particularly prevalent in women and those aged under 50. Symptoms include abdominal pain associated with altered bowel habits (i.e. diarrhea and/or constipation subtyped based on the predominant stool pattern). As IBS-D is challenging to manage with varying symptom severity, effective treatment requires a personalized management approach. Evidence-based therapeutic options endorsed by the American Gastroenterological Association and the American College of Gastroenterology can be used to effectively guide treatment. Dietary and lifestyle modifications, including adequate hydration, reducing caffeine and alcohol intake, and increasing soluble fiber intake may lead to symptom improvement. Over-the-counter medications such as loperamide are frequently recommended and may improve stool frequency and rectal urgency; however, for the outcome of abdominal pain, mixed results have been observed. Several off-label prescription medications are useful in IBS-D management, including tricyclic antidepressants, bile acid sequestrants, and antispasmodics. Three prescription medications have been approved by the FDA for IBS-D: alosetron, eluxadoline, and rifaximin.

CONCLUSIONS

IBS-D can be effectively managed in the primary care setting in the absence of alarm features. Benefits and risks of pharmacologic interventions should be weighed during treatment selection.

Irritable bowel syndrome and gut microbiota

PURPOSE OF REVIEW

To provide an overview of recent studies exploring the gut microbiota in pathogenesis and treatment of irritable bowel syndrome (IBS).

RECENT FINDINGS

Primary bacterial gut disturbances have been linked to the development and severity of IBS. Dysbiosis, or alteration in the normal intestinal flora, modulates intestinal permeability, inflammation, gut motility and likely quality of life. These biomechanical changes are associated with enteric and central nervous system processing as well. When compared to healthy controls, IBS patients display poor quality of life measures and are at increased risk of depression and anxiety. The severity of psychological and gastrointestinal symptoms in IBS has been linked with a distinct intestinal microbiota signature. Efforts to modulate intestinal dysbiosis in IBS have shown little improvement in large systematic reviews. The low FODMAP diet reduces bacteria, such as Bifidobacterum and Actinobacteria. Although rifaximin improves symptoms, it may only stimulate a transient effect on the gut microbiota. Fecal microbiota transplant does not provide prolonged symptom relief in IBS.

SUMMARY

This review elucidates recent advances in IBS and the gut microbiota. Microbiota changes are one underlying factor in perpetuating global IBS symptoms. The opportunity to exploit this disturbance through treatment modalities requires further investigation.

Management of Small Intestinal Bacterial Overgrowth in Adult Patients

The human gastrointestinal tract is a complex system of digestive pathways aided by mechanical processes, enzymes, transport molecules, and colonic bacteria. Occasionally, these bacterial components transplant to atypical locations due to various gastrointestinal imbalances or anatomical structural issues. This may lead to bacterial overgrowth of the small intestine, where minimal or no bacteria are normally found. Symptoms of small intestinal bacterial overgrowth may mimic those of various functional gastrointestinal diseases. Small intestinal bacterial overgrowth is typically diagnosed through hydrogen breath tests or jejunal aspirate culture. Current recommendations indicate antibiotics as the first-line treatment to eradicate or modify the bacterial overgrowth to a more favorable state. Nutritional support is also indicated to correct deficiencies and aid in symptom alleviation. As small intestinal bacterial overgrowth is common in other conditions, much of the research for this area is based on findings in codisease states rather than independent disease research. To provide accurate recommendations for small intestinal bacterial overgrowth, more targeted research is needed.

Irritable Bowel Syndrome: What Treatments Really Work

Irritable bowel syndrome (IBS) is present in patients with symptoms of chronic abdominal pain and altered bowel habits but no identifiable organic etiology. Rome IV classification groups patients based on predominant stool pattern. Low-FODMAP diets have been helpful in providing symptom relief, as have cognitive behavioral and mind-body techniques that help patients manage symptoms. Targeted symptomatic relief for the patient's predominant symptoms provides relief in addition to effective older medications that are inexpensive and reliable. Newer treatments for IBS-D, such as eluxadoline, and IBS-C, with linaclotide, lubiprostone, plecanatide, also can provide durable relief.

Understanding symptom burden and attitudes to irritable bowel syndrome with diarrhoea: Results from patient and healthcare professional surveys

BACKGROUND

Irritable bowel syndrome with diarrhoea (IBS-D) comprises multiple troublesome symptoms and negatively impacts patients' quality of life.

OBJECTIVE

The objective of this article is to assess IBS-D patient burden and patient and healthcare professional (HCP) attitudes towards IBS.

METHODS

Patients and HCPs from Australia, Canada, France, Germany, Italy, Spain and the United Kingdom completed internet-based surveys via market research panels. Attitudes to IBS-D-related statements were scored using seven-point Likert scales.

RESULTS

The patient survey included 513 patients (70% female, mean age 40.9 years). Faecal urgency was reported as the most troublesome symptom (27%) and fatigue occurred on the most days per month (mean: 18); 61% of patients used ≥3 types of treatment daily or intermittently; 19% used antidepressants daily. Thirty-three per cent thought HCPs should listen and provide more support and 46% reported willingness to 'try anything' to help manage their IBS-D. The HCP survey included 366 primary care physicians and 313 gastroenterologists: A total of 70% and 65%, respectively, agreed it was important that IBS-D patients feel listened to and supported; 73% agreed their main aim was to improve quality of life; ∼30% expressed frustration at managing IBS-D.

CONCLUSION

IBS-D imposes a substantial burden on patients and HCPs. These findings point towards a need for improved patient-HCP communication.

New treatments and therapeutic targets for IBS and other functional bowel disorders

Functional bowel disorders (FBDs) are a spectrum of disorders characterized by combinations of symptoms attributable to the lower gastrointestinal tract. Most current first-line therapies for IBS and other FBDs target the predominant symptom and mainly affect one symptom in the symptom complex. Additional broadly effective treatment alternatives targeting the entire symptom complex are needed. New drugs for FBDs (such as lubiprostone, linaclotide, plecanatide, prucalopride, eluxadoline and rifaximin) target key mechanisms in the pathophysiology of these disorders and improve both the abnormal bowel habit and other key symptoms, such as abdominal pain and bloating. The current development of new treatment alternatives is focusing on different aspects of the complex pathophysiology of IBS and other FBDs: gut microenvironment (via diet and modulation of gut microbiota), enterohepatic circulation of bile acids, gastrointestinal secretion, motility and sensation, gut-brain interactions, gut barrier function and the immune system within the gastrointestinal tract. Studies also suggest that personalized treatment of IBS and other FBDs is possible using various diagnostic markers.

Association Between Ultra-Processed Food Consumption and Functional Gastrointestinal Disorders: Results From the French NutriNet-Santé Cohort

OBJECTIVES

Ultra-processed foods (UPF) consumption has increased over the last decades and is raising concerns about potential adverse health effects. Our objective was to assess the association between UPF consumption and four functional gastrointestinal disorders (FGIDs): irritable bowel syndrome (IBS), functional constipation (FC), functional diarrhea (FDh), and functional dyspepsia (FDy), in a large sample of French adults.

METHODS

We analyzed dietary data of 33,343 participants from the web-based NutriNet-Santé cohort, who completed at least three 24 h food records, prior to a Rome III self-administered questionnaire. Proportion (in weight) of UPF in the diet (UPFp) was computed for each subject. The association between UPFp quartiles and FGIDs was estimated by multivariable logistic regression.

RESULTS

Participants included in the analysis were mainly women (76.4%), and the mean age was 50.4 (SD = 14.0) years. UPF accounted for 16.0% of food consumed in weight, corresponding to 33.0% of total energy intake. UPF consumption was associated with younger age, living alone, lower incomes, higher BMI, and lower physical activity level (all p < 0.0001). A total of 3516 participants reported IBS (10.5%), 1785 FC (5.4%), 1303 FDy (3.9%), and 396 FDh (1.1%). After adjusting for confounding factors, an increase in UPFp was associated with a higher risk of IBS (_aOR _{Q4 vs. Q1} [95% CI]: 1.25 [1.12-1.39], p-trend < 0.0001).

CONCLUSIONS

This study suggests an association between UPF and IBS. Further longitudinal studies are needed to confirm those results and understand the relative impact of the nutritional composition and specific characteristics of UPF in this relationship.

Rome Criteria and a Diagnostic Approach to Irritable Bowel Syndrome

Functional gastrointestinal disorders (FGIDs) account for at least 40% of all referrals to gastroenterologists. Of the 33 recognized adult FGIDs, irritable bowel syndrome (IBS) is the most prevalent, with a worldwide prevalence estimated at 12%. IBS is an important health care concern as it greatly affects patients' quality of life and imposes a significant economic burden to the health care system. Cardinal symptoms of IBS include abdominal pain and altered bowel habits. The absence of abdominal pain makes the diagnosis of IBS untenable. The diagnosis of IBS can be made by performing a careful review of the patient's symptoms, taking a thoughtful history (e.g., diet, medication, medical, surgical, and psychological history), evaluating the patient for the presence of warning signs (e.g., "red flags" of anemia, hematochezia, unintentional weight loss, or a family history of colorectal cancer or inflammatory bowel disease), performing a guided physical examination, and using the Rome IV criteria. The Rome criteria were developed by a panel of international experts in the field of functional gastrointestinal disorders. Although initially developed to guide researchers, these criteria have undergone several revisions with the intent of making them clinically useful and relevant. This monograph provides a brief overview on the development of the Rome criteria, discusses the utility of the Rome IV criteria, and reviews how the criteria can be applied clinically to diagnose IBS. In addition, a diagnostic strategy for the cost-effective diagnosis of IBS will be reviewed.

Irritable bowel syndrome diagnosis and management: A simplified algorithm for clinical practice

BACKGROUND

Effective management of irritable bowel syndrome (IBS), a common functional gastrointestinal disorder, can be challenging for physicians because of the lack of simple diagnostic tests and the wide variety of treatment approaches available.

OBJECTIVE

The objective of this article is to outline a simple algorithm for day-to-day clinical practice to help physicians navigate key stages to reaching a positive IBS diagnosis and guidance on how to prioritise the use of specific management strategies.

METHODS

This algorithm was based on the opinion of an expert panel evaluating current evidence.

RESULTS

The key principles forming the foundation of this evidence-supported algorithm are: confidently naming and explaining an IBS diagnosis for the patient, followed by assessment of key patient characteristics likely to influence the choice of therapy, such as predominant symptoms, and exploring the patient agenda and preferences. Consultation should always include education and reassurance with an explanatory model of IBS tailored to the patient. Individualised lifestyle changes, dietary modifications, pharmacological therapies, psychological strategies or a combination of interventions may be used to optimise treatment for each patient.

CONCLUSION

The simple visual tools developed here navigate the key stages to reaching a positive diagnosis of IBS, and provide a stepwise approach to patient-centred management targeted towards the most bothersome symptoms. Establishing a strong patient-physician relationship is central to all stages of the patient journey from diagnosis to effective management.

Antidepressants for irritable bowel syndrome-A systematic review

BACKGROUND

According to the multifactorial etiology of Irritable bowel syndrome (IBS), psychological factors play an important role. It is possible that antidepressant therapy may be more effective for patients with IBS. The aim of this study was a systematic review of the best available antidepressant therapies for IBS.

METHODS

The databases Medline, PubMed, EMBASE, and the Cochrane Controlled Trials Register for randomized controlled trials were searched for studies published before September 2016. Meta-analyses, randomized controlled trials, controlled trials, uncontrolled trials, cohort studies, and open-label studies were analyzed.

RESULTS

Of 513 articles, 29 fulfilled the inclusion criteria: 6 meta-analyses, 18 randomized controlled trials, and 5 studies without randomization. In these studies, the efficacy of tricyclics, selective serotonin reuptake inhibitors or serotonin-noradrenaline reuptake inhibitors, were analyzed in IBS. Different interventions were used, though in most studies their effect on global symptom relief in IBS as a primary outcome was investigated. Generally, patients' tolerance of the therapies was good. Only severe adverse events were observed as a result of the nature of the drug.

CONCLUSIONS

Generally, antidepressants improved IBS symptoms. In comparison with placebo, tricyclic therapy for IBS was more effective than selective serotonin reuptake inhibitors. Antidepressants might be an alternative therapy for patients suffering from IBS, especially diarrhea-predominant IBS.

Irritable Bowel Syndrome: Clinical Manifestations, Dietary Influences, and Management

Irritable bowel syndrome (IBS) is a functional gastrointestinal disorder that is characterized by symptoms of chronic abdominal pain and altered bowel habits in the absence of an overtly identifiable cause. It is the most commonly diagnosed functional gastrointestinal disorder, accounting for about one third of gastroenterology visits. It generally presents as a complex of symptoms, including psychological dysfunction. Hypersensitivity to certain foods, especially foods that contain high amounts of fructose, plays a role in the pathophysiology of IBS. Elevated consumption of high-fructose corn syrup (HFCS) has been discussed in this aspect. The treatment options for IBS are challenging and varied. In addition to dietary restrictions for HFCS-induced IBS, such as low-FODMAP (Fermentable Oligosaccharides, Disaccharide, Monosaccharides, and Polyols) diets, existing drug therapies are administered based on the predominant symptoms and IBS-subtype. Patients with IBS are likely to suffer from issues, such as anxiety, depression, and post-traumatic-stress disorder. Biopsychosocial factors particularly socioeconomic status, sex, and race should, thus, be considered for diagnostic evaluation of patients with IBS.

Current and emergent pharmacologic treatments for irritable bowel syndrome with diarrhea: evidence-based treatment in practice

Irritable bowel syndrome with diarrhea (IBS-D) is a common, chronic functional gastrointestinal disorder with symptoms that can be distressing for patients and often result in substantially impaired quality of life. This review focuses on providing clinicians with information on practical, evidence-based treatment for IBS-D. Current therapies commonly used for the treatment of IBS-D, including pharmacologic and nonpharmacologic interventions, are briefly reviewed, followed by discussion of the emergent pharmacologic treatments (rifaximin and eluxadoline) and medical foods (IBgard® and EnteraGam®). Given the lack of a standard treatment algorithm for IBS-D and the emergence of new pharmacologic therapies, treatment needs to be tailored to the individual patient and take into account the severity of disease. In this context, the latter part of this manuscript examines how treatments for IBS-D can be used in clinical practice by presenting three patient case scenarios with varying degrees of IBS-D severity. For each case, the patient's medical history and clinical presentation are related to the Rome Foundation multidimensional clinical profile (MDCP) and potential treatment options with current and emergent therapies are reviewed. The interplay of gastrointestinal symptoms and their psychosocial impact, as well as the importance of a patient-centered approach to therapy, are discussed. Consideration is given to the potential need for combination therapies and how emergent treatments could fit into the treatment pathway for mild, moderate, and severe cases of IBS-D in clinical practice.

Phenotyping of subjects for large scale studies on patients with IBS

BACKGROUND

Irritable bowel syndrome (IBS) is a complex condition with multiple factors contributing to its aetiology and pathophysiology. Aetiologically these include genetics, life-time events and environment, and physiologically, changes in motility, central processing, visceral sensitivity, immunity, epithelial permeability and gastrointestinal microflora. Such complexity means there is currently no specific reliable biomarker for IBS, and thus IBS continues to be diagnosed and classified according to symptom based criteria, the Rome Criteria. Carefully phenotyping and characterisation of a 'large' pool of IBS patients across Europe and even the world however, might help identify sub-populations with accuracy and consistency. This will not only aid future research but improve tailoring of treatment and health care of IBS patients.

PURPOSE

The aim of this position paper is to discuss the requirements necessary to standardize the process of selecting and phenotyping IBS patients and how to organise the collection and storage of patient information/samples in such a large multi-centre pan European/global study. We include information on general demographics, gastrointestinal symptom assessment, psychological factors, quality of life, physiological evaluation, genetic/epigenetic and microbiota analysis, biopsy/blood sampling, together with discussion on the organisational, ethical and language issues associated with implementing such a study. The proposed approach and documents selected to be used in such a study was the result of a thoughtful and thorough four-year dialogue amongst experts associated with the European COST action BM1106 GENIEUR (www.GENIEUR.eu).

Food: The Main Course to Wellness and Illness in Patients With Irritable Bowel Syndrome

Food sits at the intersection between gastrointestinal (GI) physiology and symptoms in patients with the irritable bowel syndrome (IBS). It is now clear that the majority of IBS sufferers associate eating a meal with their GI and non-GI symptoms. This is hardly surprising when one considers that food can affect a variety of physiologic factors (motility, visceral sensation, brain-gut interactions, microbiome, permeability, immune activation, and neuro-endocrine function) relevant to the pathogenesis of IBS. In recent years, clinical research has increasingly focused on diet as a treatment for IBS. There is a relative paucity of data from rigorous, randomized, controlled trials for any dietary intervention in IBS patients. Currently, the largest body of literature has addressed the efficacy of dietary restriction of fermentable oligo, di, monosaccharides, and polyols (FODMAPs). In the future, dietary treatments for IBS will move beyond the current focus on elimination to embrace supplementation with "functional" foods.

Diagnosis and treatment of diarrhea-predominant irritable bowel syndrome

Irritable bowel syndrome (IBS) is one of the most common gastrointestinal disorders worldwide. The economic impact of IBS on the health care system is substantial, as is the personal impact on patients. Patients with diarrhea-predominant IBS (IBS-D) comprise a substantial proportion of the overall IBS population. Primary care providers are often the first point of contact for patients with IBS-D and can accurately diagnose IBS after a careful history and examination without extensive diagnostic tests. Several pharmacologic treatments (eg, loperamide, alosetron, and antidepressants) and non-pharmacologic treatments (eg, dietary modification and probiotics) are available for IBS-D, but restrictions on use (eg, alosetron) or the lack of controlled trial data showing reductions in both global and individual IBS-D symptoms (eg, bloating, pain and stool frequency) emphasize the need for alternative treatment options. Two newer medications (eluxadoline and rifaximin) were approved in May 2015 for the treatment of IBS-D, and represent new treatment options for this common gastrointestinal condition.

Diagnosis and treatment of diarrhea-predominant irritable bowel syndrome

Irritable bowel syndrome (IBS) is one of the most common gastrointestinal disorders worldwide. The economic impact of IBS on the health care system is substantial, as is the personal impact on patients. Patients with diarrhea-predominant IBS (IBS-D) comprise a substantial proportion of the overall IBS population. Primary care providers are often the first point of contact for patients with IBS-D and can accurately diagnose IBS after a careful history and examination without extensive diagnostic tests. Several pharmacologic treatments (eg, loperamide, alosetron, and antidepressants) and non-pharmacologic treatments (eg, dietary modification and probiotics) are available for IBS-D, but restrictions on use (eg, alosetron) or the lack of controlled trial data showing reductions in both global and individual IBS-D symptoms (eg, bloating, pain and stool frequency) emphasize the need for alternative treatment options. Two newer medications (eluxadoline and rifaximin) were approved in May 2015 for the treatment of IBS-D, and represent new treatment options for this common gastrointestinal condition.

Emerging treatments in neurogastroenterology: eluxadoline - a new therapeutic option for diarrhea-predominant IBS

BACKGROUND

Irritable bowel syndrome (IBS) is the most common functional gastrointestinal disorder worldwide. The global prevalence of IBS is estimated to be as high as 15%. For many patients, IBS is a chronic disorder which can significantly reduce quality of life. Just as important as the effects on any one individual, IBS also places a significant impact on the population as a whole with its negative effects on the health care system. Irritable bowel syndrome is categorized into one of three main categories: IBS with diarrhea, IBS with constipation, and IBS with mixed bowel habits. Patients with diarrhea-predominant IBS (IBS-D) comprise a substantial proportion of the overall IBS population. A number of therapeutic options exist to treat the symptoms of abdominal pain, bloating, diarrhea, and fecal urgency, including non-pharmacologic therapies such as dietary changes and probiotics, or pharmacologic therapies such as loperamide and alosetron. However, many patients have persistent symptoms despite these therapies. This unmet need led to the development of eluxadoline, a mu-opioid receptor agonist/delta-opioid receptor antagonist/kappa-receptor agonist. Approved by the FDA in May 2015, this medication shows promise in the treatment of diarrhea-predominant IBS for both men and women.

PURPOSE

This monograph will briefly review the impact of IBS, discuss current treatments for IBS-D, and then focus on the pharmacology, clinical efficacy and safety of eluxadoline. Potential mechanisms related to rare events of acute pancreatitis or elevated liver tests will be discussed.