Dietary treatment of irritable bowel syndrome: current evidence and guidelines for future practice

The relationship between meal regularity with Irritable Bowel Syndrome (IBS) in adults

BACKGROUND

The irregular meal pattern and meal-skipping might be related to irritable bowel syndrome (IBS), however, findings of previous investigations are contradictory. We aimed to examine the relation of meal regularity with IBS in Iranian adult population.

METHODS

Data on 4599 adults who worked in 50 different health centers were used in this cross-sectional study. Dietary habits were measured using a pretested questionnaire. IBS identification was performed through the use of a modified version of Rome III questionnaire.

RESULTS

IBS was prevalent among 18.6% of men and 24.1% of women. After adjustment for potential confounders, those with regular meal pattern, in comparison to those with irregular meals, had 40% lower odds for IBS (OR:0.60, 95%CI: 0.41-0.87). Individuals with regular meals had also 82 lower risk for IBS-Mixed, in comparison to those who had irregular meals (OR:0.18, 0.95%CI: 0.08-0.43). Stratified analysis by gender revealed that women with regular meals, compared with those who did not, had 44% lower risk for IBS (OR: 0.56, 0.95%CI: 0.34-0.91). Normal-weight individuals who had regular meal pattern, compared to those who did not, had 63% lower risks for IBS (OR:0.37, 95%CI: 0.22-0.64). Furthermore, subjects who had regular meal pattern had 53% lower risk for severe symptoms of IBS (OR:0.47, 95%CI: 0.30-0.71).

CONCLUSION

We found that participants with regular meal pattern had reduced odds of IBS, IBS-Mixed and the syndrome severity. Meal regularity was also linked to reduced IBS prevalence in women, and in normal-weight individuals. More prospective studies are needed to affirm these associations.

The relationship between dietary intakes and prevalence of irritable bowel syndrome in adolescent girls: A cross-sectional study

BACKGROUND

Irritable bowel syndrome (IBS) is the most prevalent functional gastrointestinal disorder (FGID) leading to substantial reduction in quality of life. This study was undertaken to assess the relationship between diet and prevalence of IBS in female adolescents.

METHODS

In this cross-sectional study, data were examined on 988 adolescent girls from different areas of Mashhad and Sabzevar cities, Iran. A 168-item validated and reliable food frequency questionnaire (FFQ) for dietary intake was used in all the study participants. A diagnosis of IBS was made using the Rome III criteria.

RESULTS

Dietary macronutrients, energy, and selected micronutrients of IBS patients were similar to healthy subjects. Comparing the intake of caffeine between groups with and without IBS showed a higher level of consumption in the individuals with IBS (p-value = 0.02; p trend = 0.03). There was a significant positive association between caffeine intake and risk of IBS (odds ratio [OR] = 1.88, after adjustment for potential confounding variables). Although there was no significant difference in intakes of total dietary fiber (p-value = 0.23) and insoluble dietary fiber (p-value = 0.09) between IBS-positive and IBS-negative subjects, their soluble dietary fiber intake was significantly different (p-value = 0.02, a significant negative association was seen between soluble dietary fiber intake and IBS prevalence, after adjustment for potential confounding variables [p trend = 0.02; OR = 0.59]).

CONCLUSIONS

The higher intake of caffeine was positively associated with IBS prevalence. Additionally, a negative association was seen between soluble dietary fiber intake and the chance of having IBS.

Examining Opportunities for Goal-Directed Self-Tracking to Support Chronic Condition Management

Although self-tracking offers potential for a more complete, accurate, and longer-term understanding of personal health, many people struggle with or fail to achieve their goals for health-related self-tracking. This paper investigates how to address challenges that result from current self-tracking tools leaving a person's goals for their data unstated and lacking explicit support. We examine supporting people and health providers in expressing and pursuing their tracking-related goals via goal-directed self-tracking, a novel method to represent relationships between tracking goals and underlying data. Informed by a reanalysis of data from a prior study of migraine tracking goals, we created a paper prototype to explore whether and how goal-directed self-tracking could address current disconnects between the goals people have for data in their chronic condition management and the tools they use to support such goals. We examined this prototype in interviews with 14 people with migraine and 5 health providers. Our findings indicate the potential for scaffolding goal-directed self-tracking to: 1) elicit different types and hierarchies of management and tracking goals; 2) help people prepare for all stages of self-tracking towards a specific goal; and 3) contribute additional expertise in patient-provider collaboration. Based on our findings, we present implications for the design of tools that explicitly represent and support an individual's specific self-tracking goals.

The Dietary Management of Patients with Irritable Bowel Syndrome: A Narrative Review of the Existing and Emerging Evidence

Even though irritable bowel syndrome (IBS) has been known for more than 150 years, it still remains one of the research challenges of the 21st century. According to the current diagnostic Rome IV criteria, IBS is characterized by abdominal pain associated with defecation and/or a change in bowel habit, in the absence of detectable organic causes. Symptoms interfere with the daily life of patients, reduce health-related quality of life and lower the work productivity. Despite the high prevalence of approximately 10%, its pathophysiology is only partly understood and seems multifactorial. However, many patients report symptoms to be meal-related and certain ingested foods may generate an exaggerated gastrointestinal response. Patients tend to avoid and even exclude certain food products to relieve their symptoms, which could affect nutritional quality. We performed a narrative paper review of the existing and emerging evidence regarding dietary management of IBS patients, with the aim to enhance our understanding of how to move towards an individualized dietary approach for IBS patients in the near future.

Pharmacological and non-pharmacological treatments for irritable bowel syndrome: Protocol for a systematic review and network meta-analysis

BACKGROUND

The global prevalence of Irritable bowel syndrome (IBS) is estimated to be as high as 15% and a number of different non-pharmacological and pharmacological treatments have been used to manage IBS in clinical practice, which poses great challenges for clinicians to make appropriate decisions. Hence, a systematic review and network meta-analysis on all available pharmacological and non-pharmacological treatments for IBS is needed to provide reliable evidence.

METHODS

We will search the Cochrane Central Register of Controlled Trials (CENTRAL), the Cochrane IBD Group Specialized Trials Register, MEDLINE, EMBASE, and Chinese Biomedical medicine (CBM) from inception to 31, May 2019. Randomized controlled trials of pharmacological and nonpharmacological interventions for IBS will be included. Study quality will be assessed on the basis of the methodology and categories described in the Cochrane Collaboration Handbook. Primary outcomes are global or clinical improvement and quality of life. A Bayesian network meta-analysis would be performed, and relative ranking of agents would be assessed. A node splitting method will be used to examine the inconsistency between direct and indirect comparisons when a loop connecting 3 arms exists.

RESULTS

Researchers will rank the effectiveness and safety of the potentials interventions for IBS according the characteristics of patients by conducting an advanced network meta-analysis based on Bayesian statistical model, and interpret the results by using GRADE approach.

CONCLUSION

The conclusion of our study will provide updated evidence to rank the effectiveness and safety of pharmacological and non-pharmacological interventions for IBS.

ETHICS AND DISSEMINATION

Ethical approval is not applicable since this study is a network meta-analysis based on published trials.

PROTOCOL REGISTRATION NUMBER

CRD42018083844.

Low fermentable oligosaccharides, disaccharides, monosaccharides and polyols (FODMAP) diet improves symptoms in adults suffering from irritable bowel syndrome (IBS) compared to standard IBS diet: A meta-analysis of clinical studies

Background

Irritable bowel syndrome (IBS) and functional digestive tract disorders, e.g. functional bloating, carbohydrate maldigestion and intolerances, are very common disorders frequently causing significant symptoms that challenge health care systems. A low Fermentable Oligosaccharides, Disaccharides, Monosaccharides and Polyols (FODMAP) diet is one of the possible therapeutic approaches for decreasing abdominal symptoms and improving quality of life.

Objectives

We aimed to meta-analyze data on the therapeutic effect of a low-FODMAP diet on symptoms of IBS and quality of life and compare its effectiveness to a regular, standard IBS diet with high FODMAP content, using a common scoring system, the IBS Symptom Severity Score (IBS-SSS).

Methods

A systematic literature search was conducted in PubMed, EMBASE and the Cochrane Library as well as in the references in a recent meta-analysis. Adult patients diagnosed with IBS according to the Rome II, Rome III, Rome IV or NICE criteria were included in the analysis.

Statistical methods

Mean differences with 95% confidence intervals were calculated from studies that contained means, standard deviation (SD) or mean differences and SD of differences and p-values. A random effect model was used because of the heterogeneity (Q test (χ2) and I² indicator). A p-value of less than 0.05 was chosen to indicate a significant difference.

Results

The literature search yielded 902 publications, but only 10 were eligible for our meta-analysis. Both regular and low-FODMAP diets proved to be effective in IBS, but post-diet IBS-SSS values were significantly lower (p = 0.002) in the low-FODMAP group. The low-FODMAP diet showed a correlation with the improvement of general symptoms (by IBS-SSS) in patients with IBS.

Conclusions

This meta-analysis provides high-grade evidence of an improved general symptom score among patients with irritable bowel syndrome who have maintained a low-FODMAP diet compared to those on a traditional IBS diet, therefore showing its superiority to regular IBS dietary therapy. These data suggest that a low-FODMAP diet with dietitian control can be a candidate for first-line therapeutic modality in IBS. Because of a lack of data, well-planned randomized controlled studies are needed to ascertain the correlation between improvement of separate key IBS symptoms and the effect of a low-FODMAP diet.

Supporting Patient-Provider Collaboration to Identify Individual Triggers using Food and Symptom Journals

Patient-generated data can allow patients and providers to collaboratively develop accurate diagnoses and actionable treatment plans. Unfortunately, patients and providers often lack effective support to make use of such data. We examine patient-provider collaboration to interpret patient-generated data. We focus on irritable bowel syndrome (IBS), a chronic illness in which particular foods can exacerbate symptoms. IBS management often requires patient-provider collaboration using a patient's food and symptom journal to identify the patient's triggers. We contribute interactive visualizations to support exploration of such journals, as well as an examination of patient-provider collaboration in interpreting the journals. Drawing upon individual and collaborative interviews with patients and providers, we find that collaborative review helps improve data comprehension and build mutual trust. We also find a desire to use tools like our interactive visualizations within and beyond clinic appointments. We discuss these findings and present guidance for the design of future tools.

The feasibility, usability, and clinical utility of traditional paper food and symptom journals for patients with irritable bowel syndrome

BACKGROUND

Paper food and gastrointestinal (GI) symptom journals are used to help irritable bowel syndrome (IBS) patients determine potential trigger foods. The primary aim of this study was to evaluate the feasibility, usability, and clinical utility of such journals as a data collection tool. A secondary aim was to explore a method for analyzing journal data to describe patterns of diet and symptoms.

METHODS

Participants (N=17) were asked to log three sets of 3-day food and symptom journals over a 15-day period. Feasibility was evaluated by journal completion rates, symptom logging compliance, and logging fatigability. The feasibility, usability, and clinical utility of journaling were also assessed by a customized evaluation and exit interview. For each journal, regression analyses were conducted to examine relationships between key meal nutrients and subsequent symptoms.

KEY RESULTS

Most participants were young (mean age 35±12) Caucasian (N=13) women (N=14). Journal completion rates were 100% for all participants with no logging fatigability. Over half perceived paper journaling of food and symptoms as feasible, usable, and clinically useful. Thirteen participants demonstrated a strong association with at least one symptom and meal nutrient. Patterns of associations differed among participants.

CONCLUSIONS AND INFERENCES

Paper journaling of food and GI symptoms for 9 days over a 15-day period appeared to be a feasible and usable data collection tool for IBS patients. Over half perceived journaling as at least somewhat clinically useful. Findings from this study support the anecdote that food trigger(s) and associated symptom(s) vary for each individual.

Dietary Triggers in Irritable Bowel Syndrome: Is There a Role for Gluten?

A tight link exists between dietary factors and irritable bowel syndrome (IBS), one of the most common functional syndromes, characterized by abdominal pain/discomfort, bloating and alternating bowel habits. Amongst the variety of foods potentially evoking "food sensitivity", gluten and other wheat proteins including amylase trypsin inhibitors represent the culprits that recently have drawn the attention of the scientific community. Therefore, a newly emerging condition termed non-celiac gluten sensitivity (NCGS) or nonceliac wheat sensitivity (NCWS) is now well established in the clinical practice. Notably, patients with NCGS/NCWS have symptoms that mimic those present in IBS. The mechanisms by which gluten or other wheat proteins trigger symptoms are poorly understood and the lack of specific biomarkers hampers diagnosis of this condition. The present review aimed at providing an update to physicians and scientists regarding the following main topics: the experimental and clinical evidence on the role of gluten/wheat in IBS; how to diagnose patients with functional symptoms attributable to gluten/wheat sensitivity; the importance of double-blind placebo controlled cross-over trials as confirmatory assays of gluten/wheat sensitivity; and finally, dietary measures for gluten/wheat sensitive patients. The analysis of current evidence proposes that gluten/wheat sensitivity can indeed represent a subset of the broad spectrum of patients with a clinical presentation of IBS.

Diet low in FODMAPs reduces symptoms of irritable bowel syndrome as well as traditional dietary advice: a randomized controlled trial

BACKGROUND & AIMS

A diet with reduced content of fermentable short-chain carbohydrates (fermentable oligo-, di-, monosaccharides, and polyols [FODMAPs]) has been reported to be effective in the treatment of patients with irritable bowel syndrome (IBS). However, there is no evidence of its superiority to traditional dietary advice for these patients. We compared the effects of a diet low in FODMAPs with traditional dietary advice in a randomized controlled trial of patients with IBS.

METHODS

We performed a multi-center, parallel, single-blind study of 75 patients who met Rome III criteria for IBS and were enrolled at gastroenterology outpatient clinics in Sweden. Subjects were randomly assigned to groups that ate specific diets for 4 weeks-a diet low in FODMAPs (n = 38) or a diet frequently recommended for patients with IBS (ie, a regular meal pattern; avoidance of large meals; and reduced intake of fat, insoluble fibers, caffeine, and gas-producing foods, such as beans, cabbage, and onions), with greater emphasis on how and when to eat rather than on what foods to ingest (n = 37). Symptom severity was assessed using the IBS Symptom Severity Scale, and patients completed a 4-day food diary before and at the end of the intervention.

RESULTS

A total of 67 patients completed the dietary intervention (33 completed the diet low in FODMAPs, 34 completed the traditional IBS diet). The severity of IBS symptoms was reduced in both groups during the intervention (P < .0001 in both groups before vs at the end of the 4-week diet), without a significant difference between the groups (P = .62). At the end of the 4-week diet period, 19 patients (50%) in the low-FODMAP group had reductions in IBS severity scores ≥50 compared with baseline vs 17 patients (46%) in the traditional IBS diet group (P = .72). Food diaries demonstrated good adherence to the dietary advice.

CONCLUSIONS

A diet low in FODMAPs reduces IBS symptoms as well as traditional IBS dietary advice. Combining elements from these 2 strategies might further reduce symptoms of IBS. ClinicalTrials.gov ID NCT02107625.

Food allergy in irritable bowel syndrome: The case of non-celiac wheat sensitivity

Irritable bowel syndrome (IBS) is one of the most common gastrointestinal disorders, having a prevalence of 12%-30% in the general population. Most patients with IBS attribute their symptoms to adverse food reactions. We review the role of diet in the pathogenesis of IBS and the importance of dietary factors in the management of these patients. The MEDLINE electronic database (1966 to Jan 2015) was searched using the following keywords: "food", "diet", "food allergy", "food hypersensitivity", "food intolerance", "IBS", "epidemiology", "pathogenesis", "pathophysiology", "diagnosis", "treatment". We found 153 eligible papers; 80 were excluded because: not written in English, exclusive biochemical and experimental research, case reports, reviews, and research otherwise not relevant to our specific interest. We selected 73 papers: 43 original papers, 26 reviews and 4 letters to the editor. These papers focused on IBS pathogenesis, the association between IBS and atopy, and between IBS and food allergy, the relationship between IBS and non-celiac wheat sensitivity, the role of diet in IBS. Pending further scientific evidence, a cautious approach is advisable but the concept of food allergy should be included as a possible cause of IBS, and a dietary approach may have a place in the routine clinical management of IBS.

Gut-directed guided affective imagery as an adjunct to dietary modification in irritable bowel syndrome

This work aimed to study the effect of guided affective imagery on the irritable bowel syndrome. A total of 15 irritable bowel syndrome patients received guided affective imagery and 19 patients served as controls. Symptom severity and irritable bowel syndrome quality of life were measured at baseline and 8 weeks. Symptom severity decreased following guided affective imagery compared to controls (−1.5 ± 1.9 vs 0.1 ± 1.6, p = 0.04). Irritable bowel syndrome quality of life increased following guided affective imagery compared to controls (12.1 ± 12.5 vs −0.7 ± 16.2, p < 0.01). Guided affective imagery predicted reduced symptom severity (odds ratio = 5.71, p = 0.02) and increased irritable bowel syndrome quality of life (odds ratio = 17.88, p = 0.01). Guided affective imagery combined with dietary modification may be beneficial in the management of irritable bowel syndrome, however larger studies are required.

Breath tests and irritable bowel syndrome

Breath tests are non-invasive tests and can detect H₂ and CH₄ gases which are produced by bacterial fermentation of unabsorbed intestinal carbohydrate and are excreted in the breath. These tests are used in the diagnosis of carbohydrate malabsorption, small intestinal bacterial overgrowth, and for measuring the orocecal transit time. Malabsorption of carbohydrates is a key trigger of irritable bowel syndrome (IBS)-type symptoms such as diarrhea and/or constipation, bloating, excess flatulence, headaches and lack of energy. Abdominal bloating is a common nonspecific symptom which can negatively impact quality of life. It may reflect dietary imbalance, such as excess fiber intake, or may be a manifestation of IBS. However, bloating may also represent small intestinal bacterial overgrowth. Patients with persistent symptoms of abdominal bloating and distension despite dietary interventions should be referred for H₂ breath testing to determine the presence or absence of bacterial overgrowth. If bacterial overgrowth is identified, patients are typically treated with antibiotics. Evaluation of IBS generally includes testing of other disorders that cause similar symptoms. Carbohydrate malabsorption (lactose, fructose, sorbitol) can cause abdominal fullness, bloating, nausea, abdominal pain, flatulence, and diarrhea, which are similar to the symptoms of IBS. However, it is unclear if these digestive disorders contribute to or cause the symptoms of IBS. Research studies show that a proper diagnosis and effective dietary intervention significantly reduces the severity and frequency of gastrointestinal symptoms in IBS. Thus, diagnosis of malabsorption of these carbohydrates in IBS using a breath test is very important to guide the clinician in the proper treatment of IBS patients.

Nutrient intake in patients with irritable bowel syndrome compared with the general population

BACKGROUND

Food and diet are central issues that concern patients with irritable bowel syndrome (IBS). Few studies have thoroughly analyzed dietary intake in IBS. Our aims were to determine the nutrient intake in IBS patients in comparison to the general population, assess nutritional differences between IBS subgroups based on the predominant bowel habit or symptom severity, as well as to evaluate if their nutrient intake meet nutrition recommendations.

METHODS

We included 187 IBS patients (mean 40.2 years; 139 women). They completed a 4-days food registration record, which was compared with an age-, and gender-matched control group (n = 374; 278 women) from a nation-wide dietary survey and with Nordic Nutrient Recommendations.

KEY RESULTS

Daily nutrient intake in IBS patients was similar to the general population and met national nutrients recommendations. Irritable bowel syndrome patients had similar energy distribution from macronutrients compared to the control group, but the protein percentage tended to be higher. Irritable bowel syndrome patients also had significantly higher daily intake of vitamin E, folate, iron, vitamin C, and dietary fibers, as well as lower intake of vitamin A, riboflavin, calcium, and potassium. There was no association between nutrient intake and IBS subtypes or symptom severity.

CONCLUSIONS & INFERENCES

Although many IBS patients state that they avoid food items, this does not seem to influence their intake of nutrients to any large extent. The observed minor differences in nutrient intake indicate a tendency toward higher intake of fruit and vegetables and a lower intake of meat and dairy products in IBS patients.

Review article: Associations between immune activation, intestinal permeability and the irritable bowel syndrome

BACKGROUND

Irritable bowel syndrome (IBS), one of the most common gastrointestinal disorders, markedly impairing patients' quality of life. Drug development for IBS treatment has been hampered by the lack of understanding of IBS aetiology. In recent years, numerous data have emerged that suggest the involvement of immune activation in IBS, at least in a subset of patients.

AIM

To determine whether immune activation and intestinal permeabilisation are more frequently observed in IBS patients compared with healthy controls.

METHODS

The scientific bibliography was searched using the following keywords: irritable bowel syndrome, inflammation, immune activation, permeabilisation, intestine, assay, histology and human. The retrieved studies, including blood, faecal and histological studies, were analysed to provide a comprehensive and structured overview of the available data including the type of assay, type of inflammatory marker investigated or intestinal segment studied.

RESULTS

Immune activation was more frequently observed in IBS patients than in healthy controls. An increase in the number of mast cells and lymphocytes, an alteration in cytokine levels and intestinal permeabilisation were reported in IBS patients. No consistent changes in the numbers of B cells or enterochromaffin cells or in mucosal serotonin production were demonstrated.

CONCLUSIONS

The changes observed were modest and often heterogeneous among the studied population. Only appropriate interventions improving irritable bowel syndrome symptoms could highlight and confirm the role of immune activation in this pathophysiology.

Meditation over medication for irritable bowel syndrome? On exercise and alternative treatments for irritable bowel syndrome

Complimentary alternative treatment regimens are widely used in irritable bowel syndrome (IBS), but the evidence supporting their use varies. For psychological treatment options, such as cognitive behavioral therapy, mindfulness, gut-directed hypnotherapy, and psychodynamic therapy, the evidence supporting their use in IBS patients is strong, but the availability limits their use in clinical practice. Dietary interventions are commonly included in the management of IBS patients, but these are primarily based on studies assessing physiological function in relation to dietary components, and to a lesser degree upon research examining the role of dietary components in the therapeutic management of IBS. Several probiotic products improve a range of symptoms in IBS patients. Physical activity is of benefit for health in general and recent data implicates its usefulness also for IBS patients. Acupuncture does not seem to have an effect beyond placebo in IBS. A beneficial effect of some herbal treatments has been reported.

British Dietetic Association evidence-based guidelines for the dietary management of irritable bowel syndrome in adults

BACKGROUND

 Irritable bowel syndrome (IBS) is a chronic debilitating functional gastrointestinal disorder. Diet and lifestyle changes are important management strategies. The aim of these guidelines is to systematically review key aspects of the dietary management of IBS, with the aim of providing evidence-based guidelines for use by registered dietitians.

METHODS

Questions relating to diet and IBS symptom management were developed by a guideline development group. These included the role of milk and lactose, nonstarch polysaccharides (NSP), fermentable carbohydrates in abdominal bloating, probiotics and empirical or elimination diets. A comprehensive literature search was conducted and relevant studies from January 1985 to November 2009 were identified using the electronic database search engines: Cinahl, Cochrane Library, Embase, Medline, Scopus and Web of Science. Evidence statements, recommendations, good practice points and research recommendations were developed.

RESULTS

Thirty studies were critically appraised. A dietetic care pathway was produced following a logical sequence of treatment and formed the basis of these guidelines. Three lines of dietary management were identified. first line: Clinical and dietary assessment, healthy eating and lifestyle management with some general advice on lactose and NSP. Second line: Advanced dietary interventions to improve symptoms based on NSP, fermentable carbohydrates and probiotics. Third line: Elimination and empirical diets. Research recommendations were also identified relating to the need for adequately powered and well designed randomised controlled trials.

CONCLUSIONS

These guidelines provide evidence-based details of how to achieve the successful dietary management of IBS.

Bulking agents, antispasmodics and antidepressants for the treatment of irritable bowel syndrome

BACKGROUND

Irritable bowel syndrome (IBS) is a common chronic gastrointestinal disorder. The role of pharmacotherapy for IBS is limited and focused mainly on symptom control.

OBJECTIVES

The objective of this systematic review was to evaluate the efficacy of bulking agents, antispasmodics and antidepressants for the treatment of irritable bowel syndrome.

SEARCH STRATEGY

Computer assisted structured searches of MEDLINE, EMBASE, The Cochrane library, CINAHL and PsychInfo were conducted for the years 1966-2009. An updated search in April 2011 identified 10 studies which will be considered for inclusion in a future update of this review.

SELECTION CRITERIA

Randomized controlled trials comparing bulking agents, antispasmodics or antidepressants with a placebo treatment in patients with irritable bowel syndrome aged over 12 years were considered for inclusion. Only studies published as full papers were included. Studies were not excluded on the basis of language. The primary outcome had to include improvement of abdominal pain, global assessment or symptom score.

DATA COLLECTION AND ANALYSIS

Two authors independently extracted data from the selected studies. Risk Ratios (RR) and Standardized Mean Differences (SMD) with 95% confidence intervals (CI) were calculated. A proof of practice analysis was conducted including sub-group analyses for different types of  bulking agents, spasmolytic agents or antidepressant medication. This was followed by a proof of principle analysis where only the studies with adequate allocation concealment were included.

MAIN RESULTS

A total of 56 studies (3725 patients) were included in this review. These included 12 studies of bulking agents (621 patients), 29 of antispasmodics (2333 patients), and 15 of antidepressants (922 patients). The risk of bias was low for most items. However, selection bias is unclear for many of the included studies because the methods used for randomization and allocation concealment were not described. No beneficial effect for bulking agents over placebo was found for improvement of abdominal pain (4 studies; 186 patients; SMD 0.03; 95% CI -0.34 to 0.40; P = 0.87), global assessment (11 studies; 565 patients; RR 1.10; 95% CI 0.91 to 1.33; P = 0.32) or symptom score (3 studies; 126 patients SMD -0.00; 95% CI -0.43 to 0.43; P = 1.00). Subgroup analyses for insoluble and soluble fibres also showed no statistically significant benefit. Separate analysis of the studies with adequate concealment of allocation did not change these results. There was a beneficial effect for antispasmodics over placebo for improvement of abdominal pain (58% of antispasmodic patients improved compared to 46% of placebo; 13 studies; 1392 patients; RR 1.32; 95% CI 1.12 to 1.55; P < 0.001; NNT = 7), global assessment (57% of antispasmodic patients improved compared to 39% of placebo; 22 studies; 1983 patients; RR 1.49; 95% CI 1.25 to 1.77; P < 0.0001; NNT = 5) and symptom score (37% of antispasmodic patients improved compared to 22% of placebo; 4 studies; 586 patients; RR 1.86; 95% CI 1.26 to 2.76; P < 0.01; NNT = 3). Subgroup analyses for different types of antispasmodics found statistically significant benefits for cimteropium/ dicyclomine, peppermint oil, pinaverium and trimebutine. Separate analysis of the studies with adequate allocation concealment found a significant benefit for improvement of abdominal pain. There was a beneficial effect for antidepressants over placebo for improvement of abdominal pain (54% of antidepressants patients improved compared to 37% of placebo; 8 studies; 517 patients; RR 1.49; 95% CI 1.05 to 2.12; P = 0.03; NNT = 5), global assessment (59% of antidepressants patients improved compared to 39% of placebo; 11 studies; 750 patients; RR 1.57; 95% CI 1.23 to 2.00; P < 0.001; NNT = 4) and symptom score (53% of antidepressants patients improved compared to 26% of placebo; 3 studies; 159 patients; RR 1.99; 95% CI 1.32 to 2.99; P = 0.001; NNT = 4). Subgroup analyses showed a statistically significant benefit for selective serotonin releasing inhibitors (SSRIs) for improvement of  global assessment and for tricyclic antidepressants (TCAs) for improvement of abdominal pain and symptom score. Separate analysis of studies with adequate allocation concealment found a significant benefit for improvement of symptom score and global assessment. Adverse events were not assessed as an outcome in this review.

AUTHORS' CONCLUSIONS

There is no evidence that bulking agents are effective for treating IBS.  There is evidence that antispasmodics are effective for the treatment of IBS. The individual subgroups which are effective include: cimetropium/dicyclomine, peppermint oil, pinaverium and trimebutine. There is good evidence that antidepressants are effective for the treatment of IBS. The subgroup analyses for SSRIs and TCAs are unequivocal and their effectiveness may depend on the individual patient. Future research should use rigorous methodology and valid outcome measures.

Treatment of irritable bowel syndrome in women

Irritable bowel syndrome (IBS) is a complex clinical process with multiple pathophysiologic mechanisms. There has recently been a shift in the treatment of patients with severe IBS symptoms to disease-modifying therapies as opposed to symptomatic treatment. Because pathophysiologic differences exist between men and women, so does the efficacy of treatment options. These differences could further explain gender-related differences in disease prevalence and treatment response. A brief discussion of the definition, epidemiology, and diagnostic criteria of IBS is followed by a comprehensive review of the current treatment choices and potential future therapeutic options of IBS in women.

Irritable bowel syndrome: can nutrient manipulation help?

PURPOSE OF REVIEW

To describe the evidences for the usefulness of dietary manipulations (including the use of probiotics and prebiotics) in the management of irritable bowel syndrome (IBS).

RECENT FINDINGS

Exclusion diets do not have a role in the management of these patients except in the case of malabsorbed sugars (lactose, fructose). However, recent work suggests that excluding these sugars is more effective in non-IBS than in IBS patients. Also, the first small open series on the use of very low (20 g/day) carbohydrate diet (VLCD) in IBS has been published with promising results. However, safety concerns do not allow us to recommend them. In the period of review, further evidence has been provided on the role of psyllium in IBS. Also, the available evidence on the use of probiotics in IBS has been meta-analyzed.

SUMMARY

IBS patients should eat a balanced diet without restrictions, and (except for malabsorbed sugars) exclusion diets are not useful in most of them. The role of VLCD remains to be established. The concept that increasing fiber intake is useful for IBS may not be true for all patients, and hydrophilic colloids (e.g. psyllium) are preferred. There is growing evidence for the effectiveness of probiotics in IBS.

Are rice and spicy diet good for functional gastrointestinal disorders?

Rice- and chili-containing foods are common in Asia. Studies suggest that rice is completely absorbed in the small bowel, produces little intestinal gas and has a low allergenicity. Several clinical studies have demonstrated that rice-based meals are well tolerated and may improve gastrointestinal symptoms in functional gastrointestinal disorders (FGID). Chili is a spicy ingredient commonly use throughout Asia. The active component of chili is capsaicin. Capsaicin can mediate a painful, burning sensation in the human gut via the transient receptor potential vanilloid-1 (TRPV1). Recently, the TRPV1 expressing sensory fibers have been reported to increase in the gastrointestinal tract of patients with FGID and visceral hypersensitivity. Acute exposure to capsaicin or chili can aggravate abdominal pain and burning in dyspepsia and IBS patients. Whereas, chronic ingestion of natural capsaicin agonist or chili has been shown to decrease dyspeptic and gastroesophageal reflux disease (GERD) symptoms. The high prevalence of spicy food in Asia may modify gastrointestinal burning symptoms in patients with FGID. Studies in Asia demonstrated a low prevalence of heartburn symptoms in GERD patients in several Asian countries. In conclusion rice is well tolerated and should be advocated as the carbohydrate source of choice for patients with FGID. Although, acute chili ingestion can aggravate abdominal pain and burning symptoms in FGID, chronic ingestion of chili was found to improve functional dyspepsia and GERD symptoms in small randomized, controlled studies.

Irritable bowel syndrome: epidemiology, diagnosis and treatment: an update for health-care practitioners

Irritable bowel syndrome (IBS), a chronic gastrointestinal disorder, affects from 3-20% of the US population, depending on sociocultural and comorbid factors. IBS is characterized by a symptom complex of abdominal pain and abnormal bowel habits that present as diarrhea or constipation, and general physical weakness in the absence of abnormal morphological, histological or inflammatory markers. The main diagnostic Rome III criteria as established by international professional organizations are based on exclusion criteria and the occurrence and rate of symptoms. Because the pathophysiology and causes of IBS are poorly understood, treatment approaches are mainly focused on symptom management to maintain everyday functioning and improve quality of life for persons with IBS. The mainstay of intervention is pharmacological treatment with antispasmodics and antidiarrheals for diarrhea, prokinetics and high-fiber diets for constipation, and supportive therapy with low-dose antidepressants to normalize gastrointestinal motility. Other interventions include lifestyle and dietary changes, psychotherapy, herbal therapies and acupuncture. The purpose of this review is to critically assess benefits and risks of current treatment approaches as well as promising complementary and alternative therapies.

Irritable bowel syndrome: role of food in pathogenesis and management

Patients with the irritable bowel syndrome (IBS) commonly report the precipitation of symptoms on food ingestion. Though the role of dietary constituents in IBS has not been extensively studied, food could contribute to symptom onset or even the causation of IBS through a number of mechanisms. First, the physiological response of the intestine to food ingestion could precipitate symptoms in predisposed individuals; second, there is some evidence that allergy or intolerance to a particular food can produce IBS-like symptoms, third, certain foods may alter the composition of the luminal milieu, either directly or indirectly through effects on bacterial metabolism, and thus induce symptoms and, finally, IBS may develop following exposure to food-borne pathogens. Anticipatory, psychological factors generated by previous negative experiences with food ingestion or other factors may also contribute though their contribution has been scarcely quantified. Not surprisingly, there is considerable interest in the potential roles of diet and food supplements in the therapy of IBS; for the most part, the evidence base for such recommendations remains slim though certain probiotics show considerable promise.

The role of diet in symptoms of irritable bowel syndrome in adults: a narrative review

This review summarizes what is known about the effect of diet on irritable bowel syndrome (IBS) symptoms emphasizing data from randomized, controlled clinical trials. Studies suggest that IBS symptoms in one quarter of patients may be caused or exacerbated by one or more dietary components. Recent studies indicate that a diet restricted in fermentable, poorly absorbed carbohydrates, including fructose, fructans (present in wheat and onions), sorbitol, and other sugar alcohols is beneficial, but confirmatory studies are needed. Despite a long history of enthusiastic use, fiber is marginally beneficial. Insoluble fiber may worsen symptoms. Some patients with IBS, especially those with constipation, will improve with increased intake of soluble fiber. Prebiotic fibers have not been adequately tested. Daily use of peppermint oil is effective in relieving IBS symptoms. The usefulness of probiotics in the form of foods such as live-culture yogurt and buttermilk for IBS symptoms is not established. In clinical practice, it is very difficult to establish that a patient's symptoms result from an adverse reaction to food. A double blind placebo-controlled food challenge is the most reliable method, but it is not suitable for routine clinical use. A modified exclusion diet and stepwise reintroduction of foods or trials of eliminating classes of food may be useful.

A very low-carbohydrate diet improves symptoms and quality of life in diarrhea-predominant irritable bowel syndrome

BACKGROUND & AIMS

Patients with diarrhea-predominant irritable bowel syndrome (IBS-D) anecdotally report symptom improvement after initiating a very low-carbohydrate diet (VLCD). This study prospectively evaluated a VLCD in IBS-D.

METHODS

Participants with moderate to severe IBS-D were provided a 2-week standard diet, then 4 weeks of a VLCD (20 g carbohydrates/d). A responder was defined as having adequate relief of gastrointestinal symptoms for 2 or more weeks during the VLCD. Changes in abdominal pain, stool habits, and quality of life also were measured.

RESULTS

Of the 17 participants enrolled, 13 completed the study and all met the responder definition, with 10 (77%) reporting adequate relief for all 4 VLCD weeks. Stool frequency decreased (2.6 +/- 0.8/d to 1.4 +/- 0.6/d; P < .001). Stool consistency improved from diarrheal to normal form (Bristol Stool Score, 5.3 +/- 0.7 to 3.8 +/- 1.2; P < .001). Pain scores and quality-of-life measures significantly improved. Outcomes were independent of weight loss.

CONCLUSIONS

A VLCD provides adequate relief, and improves abdominal pain, stool habits, and quality of life in IBS-D.

Development of an educational intervention for patients with Irritable Bowel Syndrome (IBS): a pilot study

Background

Many IBS patients experience that they receive limited information and that the health care system does not take their complaints seriously. We aimed to develop a structured patient education, an 'IBS school', and investigate if the efficacy could be evaluated in terms of improved knowledge, symptom severity and health related quality of life (HRQOL).

Methods

The IBS school consisted of six weekly two hour sessions in a group setting. Five different health care professionals were responsible for one session each. Questionnaires covering patients' experience of the education, perceived knowledge about IBS, gastrointestinal symptoms, and HRQOL, were used for evaluation at baseline and at three, six, and twelve months after education.

Results

Twelve IBS patients were included. The patients were overall satisfied with the IBS school. In line with this, the gastrointestinal symptoms, HRQOL, and perceived knowledge about IBS improved significantly after the education.

Conclusion

An IBS school seems to be a proper method to meet the patients' need of information about IBS and also to improve the patients' gastrointestinal symptoms, HRQOL, and knowledge about IBS. Further controlled studies are now needed in larger numbers of patients to confirm these preliminary results in order to implement this intervention in clinical practice.

Review article: lactose intolerance in clinical practice--myths and realities

BACKGROUND

Approximately 70% of the world population has hypolactasia, which often remains undiagnosed and has the potential to cause some morbidity. However, not everyone has lactose intolerance, as several nutritional and genetic factors influence tolerance.

AIMS

To review current clinical practice and identify published literature on the management of lactose intolerance.

METHODS

PubMed was searched using the terms lactose, lactase and diet to find original research and reviews. Relevant articles and clinical experience provided the basis for this review.

RESULTS

Lactose is found only in mammalian milk and is hydrolysed by lactase in the small intestine. The lactase gene has recently been identified. 'Wild-type' is characterized by lactase nonpersistence, often leading to lactose intolerance. Two genetic polymorphisms responsible for persistence have been identified, with their distribution concentrated in north Europeans. Symptoms of lactose intolerance include abdominal pain, bloating, flatulence and diarrhoea. Diagnosis is most commonly by the lactose hydrogen breath test. However, most people with hypolactasia, if given appropriate advice, can tolerate some lactose-containing foods without symptoms.

CONCLUSION

In clinical practice, some people with lactose intolerance can consume milk and dairy foods without developing symptoms, whereas others will need lactose restriction.

Characterization of irritable bowel syndrome and constipation in children with allergic diseases

Allergy is believed to play a role in the pathogenesis of irritable bowel syndrome (IBS) and constipation. We investigated whether allergic patients are more prone to constipation or IBS. In a multicenter study, two groups of outpatient children aged 3-13 years were included. In group 1, children with allergic symptoms were enrolled. Group 2 consisted of nonallergic children. In both groups, the assessment of IBS and constipation was carried out using a questionnaire based on the Rome criteria for functional gastrointestinal disorders. All children were examined and underwent skin prick tests (SPT) to foods and aeroallergens. The allergic group (n=196) and controls (n=127) were comparable with respect to sex, age, and anthropometric parameters. IBS was found in 6.6% of the allergic children and in 6.3% of the controls (p=0.581). The frequency of constipation was similar in the two groups. In allergic children, positive SPTs to food and self-reported reactions to food were associated with IBS. Our results show that evaluation of constipation comorbidity is not required in allergic children. In allergic children with positive SPT to foods attention may be paid to IBS symptoms.

Nutritional aspects in patients with functional gastrointestinal disorders and motor dysfunction in the gut. Working team report of the Swedish Motility Group (SMoG)

In reviews regarding the management of patients with functional gastrointestinal disorders and motility disturbances within the gut nutritional aspects and dietary advice is often put forward as being of great importance. However, there are relatively few high-quality, interventional studies in the literature supporting an important role for general dietary advice to improve symptoms in these patients. Nutritional supplementation to patients with malnutrition due to severe dysfunction of the gastrointestinal tract is of course less controversial, even though different views on how this should be performed exist. The content of this article is based on presentations given by the authors during the second meeting of the Swedish Motility Group held in Gothenburg in March 2005, and aims to give an overview on the role of dietary advice and nutritional supplementation to patients with gastrointestinal dysfunction of different severity.

Lipid-induced colonic hypersensitivity in the irritable bowel syndrome: the role of bowel habit, sex, and psychologic factors

BACKGROUND & AIMS

Duodenal lipid infusion increases colonic hypersensitivity in irritable bowel syndrome (IBS). Whether this is affected by bowel habit, psychologic factors, or sex is unknown.

METHODS

We included 61 patients with IBS (50 women, 11 men), 25 with diarrhea-predominant IBS, 17 with constipation-predominant IBS, 19 with alternating-type IBS, and 20 healthy controls (15 women, 5 men). A colonic distension trial was performed with a barostat before and after a 1-hour duodenal lipid infusion (3 kcal/min). Colonic thresholds, colonic tone, and the viscerosomatic referral pattern were assessed and compared between groups. Patients also completed the Hospital Anxiety and Depression scale.

RESULTS

The reduction in colonic pressure thresholds after vs before duodenal lipids was greater in patients than in controls for discomfort (P = .006) and pain (P < .0001). An increased viscerosomatic referral area for pain and discomfort during colonic distensions after vs before duodenal lipids was observed in patients but not in controls. The response was similar in IBS subgroups based on the predominant bowel habit, in patients with vs without anxiety and/or depression, and in women and men with IBS. The colonic tone response during lipid infusion was similar in IBS patients and controls, and in the different IBS subgroups.

CONCLUSIONS

IBS patients show increased colonic sensitivity and altered viscerosomatic referral pattern after duodenal lipids. This response is largely unaffected by the predominant bowel habit, psychologic factors, or sex, but seems to be related to IBS per se.

Treatment of irritable bowel syndrome in outpatients with inflammatory bowel disease using a food and beverage intolerance, food and beverage avoidance diet

Irritable bowel syndrome (IBS) in the outpatient with chronic inflammatory bowel disease (IBD) is a difficult but important challenge to recognize and treat. It is very helpful to have effective treatment approaches for IBS that are practical and use minimal medications. Because of the underlying chronic inflammation in IBD, IBS symptoms occur with increased frequency and severity, secondary to increased hypersensitivity to foods and beverages that stimulate the gastrointestinal tract. This paper discusses how to treat IBS in the IBD outpatient, with emphasis on using a food and beverage intolerance, avoidance diet. The adverse effects of many foods and beverages are amount dependent and can be delayed, additive, and cumulative. The specific types of foods and beverages that can induce IBS symptoms include milk and milk containing products; caffeine containing products; alcoholic beverages; fruits; fruit juices; spices; seasonings; diet beverages; diet foods; diet candies; diet gum; fast foods; condiments; fried foods; fatty foods; multigrain breads; sourdough breads; bagels; salads; salad dressings; vegetables; beans; red meats; gravies; spaghetti sauce; stews; nuts; popcorn; high fiber; and cookies, crackers, pretzels, cakes, and pies. The types of foods and beverages that are better tolerated include water; rice; plain pasta or noodles; baked or broiled potatoes; white breads; plain fish, chicken, turkey, or ham; eggs; dry cereals; soy or rice based products; peas; applesauce; cantaloupe; watermelon; fruit cocktail; margarine; jams; jellies; and peanut butter. Handouts that were developed based upon what worsens or helps IBS symptoms in patients are included to help patients learn which foods and beverages to avoid and which are better tolerated.

Applied principles of neurogastroenterology: physiology/motility sensation

Many of the symptoms prominent in the functional gastrointestinal disorders (FGIDs) are consistent with dysfunction of the sensory and/or motor apparatus of the digestive tract. Assessment of these phenomena in man can be undertaken by using a wide variety of invasive and noninvasive techniques, some well established and others requiring further validation. By using such techniques, alterations in both sensory and motor function have been reported in the FGIDs; various combinations of such dysfunction occur in different regions of the digestive tract in the FGIDs. Our understanding of the origins of this gut sensorimotor dysfunction is gradually increasing. Thus, inflammatory, immunologic, and other processes, as well as psychosocial factors such as stress, can alter the normal patterns of sensitivity and motility through alterations in local reflex activity or via altered neural processing along the brain-gut axis. In this context, a potential role of genetic factors, early-life influences, enteric flora, dietary components, and autonomic dysfunction also should be considered in the disease model. A firm relationship between sensorimotor dysfunction and the production of symptoms, however, has been difficult to show, and so the clinical relevance of the former requires continuing exploration. Based on the conceptual framework established to date, a number of recommendations for further progress can be made.

Sugar malabsorption in functional abdominal bloating: a pilot study on the long-term effect of dietary treatment

BACKGROUND

Functional abdominal bloating is a functional bowel disorder dominated by a feeling of abdominal fullness without sufficient criteria for another functional gastrointestinal disorder. Gas-related complaints (i.e., passage of flatus), which are present in a subgroup of these patients, might be associated with carbohydrate malabsorption.

AIM

To evaluate the presence of lactose and/or fructose plus sorbitol malabsorption, and the long-term efficacy of malabsorbed sugar-free diets, in patients with Rome II criteria of functional abdominal bloating and gas-related symptoms.

METHODS

Thirty-six consecutive patients (age, 51+/-3.1 years; sex, 12 M, 24 W) with Rome II criteria of functional abdominal bloating and gas-related symptoms were included in a pilot study. In all cases, the presence of malabsorption of both lactose (20 g) and fructose plus sorbitol (20+3.5 g) was assessed by means of hydrogen breath test. Patients with sugar malabsorption were put on a malabsorbed sugar-free diet. Follow-up visits were scheduled at both 1 and 12 months after starting the diet. Global rating scales of change as compared to the beginning of the study were used to assess symptom changes.

RESULTS

Twenty-six of 36 patients (72.2%) presented sugar malabsorption (six lactose, 12 fructose plus sorbitol, and eight both). Seventeen of the 26 (65%) patients with malabsorption had symptoms of sugar intolerance during the 3-h breath testing period. All 26 were put on malabsorbed sugar-free diets. Eighty-one per cent of patients referred clinical improvement at 1-month visit, which was maintained at 12 months in 67% of them (complete improvement in 50% and partial improvement in 16.7%).

CONCLUSIONS

Sugar malabsorption and intolerance seem to be frequent in patients with functional abdominal bloating and gas-related complaints. A malabsorbed sugar-free diet might be a long-term effective therapy in a high percentage of patients. Further controlled clinical trials are warranted.

Nutrition and motility disorders

The purpose of this article is to give an overview of the relation between feeding and gastrointestinal symptoms and complaints, and to review different motility disorders that have implications for food intake. We also report the consequences for nutrition state and the evidence-based principles of dietary modification in patients with motility disorders.

The value of a general therapeutic approach in subjects with irritable bowel syndrome

BACKGROUND

The general therapeutic approach is the cornerstone in the management of irritable bowel syndrome, but the effect is poorly documented.

AIM

To evaluate the effect of the general therapeutic approach for irritable bowel syndrome.

METHODS

Subjects with irritable bowel syndrome identified in a public screening were included. Scores for abdominal symptom (range 0-12), musculoskeletal pain and mood disorders were calculated. After exclusion of other disorders, a doctor presented irritable bowel syndrome as a positive diagnosis, gave information, reassurance and lifestyle advice, but no pharmacotherapy. A dietician gave dietary advice. There was a follow-up after 6 months.

RESULTS

Sixty-five persons (females/males: 44/21) with mean age 49 years (range 31-76) were included, 31 (48%) were recommended dietary changes. Twenty subjects (31%) had satisfactory relief of symptoms after 6 months. The scores for abdominal symptom was reduced from 3.1 to 2.2 (P = 0.007), the reduction was 2.2 in the diarrhoea-predominant group given advice compared with 0.4 in the other subjects (P = 0.035). Previous consultations for the complaints, visits for psychiatric disorders, and presence of mood disorders were predictors of persistent complaints.

CONCLUSIONS

There was a significant relief of symptoms after 6 months, those with psychological co-morbidity responded less well. The effect of dietary advice was only seen in those with diarrhoea-predominant irritable bowel syndrome.

Dietary Treatment of the Irritable Bowel Syndrome

Most patients with functional gastrointestinal disorders report that food ingestion appears to exacerbate their symptoms and consequently conclude that they have some form of gastrointestinal food allergy or intolerance. Dietary management of functional gastrointestinal conditions is an attractive therapeutic option for the patient and physician alike because it is safe and economical and empowers the patient to help themselves. However, in practice, dietary manipulation frequently yields rather disappointing results. Exclusion diets can be helpful, but are labor intensive and occasionally can be very restrictive. Laboratory testing for immunoglobulin E food antibodies usually is not helpful, except in a small subgroup of patients with diarrhea, predominant irritable bowel syndrome (IBS), and atopy. There is some preliminary evidence to suggest that elimination diets based on immunoglobulin G food antibody testing may possibly have therapeutic potential in IBS, but this requires confirmation.

Effects of multidisciplinary education on outcomes in patients with irritable bowel syndrome

BACKGROUND & AIMS

The impact of education on irritable bowel syndrome (IBS) is not well known. This study evaluated the effect of a onetime group education program on patient-based outcomes in IBS.

METHODS

All adults referred by Mayo Clinic physicians to the Gastroenterology Division with a diagnosis of IBS between May 1997 and March 1998 were asked to participate. Questionnaires were administered at baseline and 6 months. Symptom resolution, change in pain severity, quality of life, Health-Promoting Lifestyle Profile score, overall patient satisfaction, and health care utilization were compared among those patients who attended the multidisciplinary class and those who did not.

RESULTS

Of the 506 patients approached, 403 (80%) agreed to participate. The clinical diagnosis was confirmed in 344 patients (85%) on chart review; 211 patients (61%) subsequently completed a follow-up questionnaire. Overall, 29% of class attendees who met Rome criteria for IBS at baseline no longer met Rome criteria at follow-up, compared with 7% of nonattendees. By multivariate analysis, class attendance predicted higher odds of not meeting Rome criteria at follow-up in individuals meeting Rome criteria at baseline (odds ratio, 7.91; 95% confidence interval, 0.97-64.41) than in nonattendees, but the opposite effect was seen with class attendance in those not meeting Rome criteria at baseline. This interaction between baseline Rome status and class attendance was significant (P < 0.05). Class attendance was associated with improvement in Health-Promoting Lifestyle Profile scores (P < 0.05) but not with change in pain, quality of life, satisfaction, or health care utilization.

CONCLUSIONS

A onetime, multidisciplinary class for patients with IBS was associated with improvement in symptoms and health-promoting lifestyle behavior.

Food Intolerance: Dietary Treatments in Functional Bowel Disorders

Currently, there is little convincing scientific evidence from well-designed trials to support the role of dietary modification or exclusions in irritable bowel syndrome (IBS). Similarly, there is an absence of conclusive data linking any dietary components directly to the pathogenesis of IBS. The role of diet, as a single modality, is unlikely to play a major role in treating IBS. Dietary modifications should be viewed as a valuable part of a multicomponent management approach in combination with other strategies such as lifestyle, behavioral, and pharmacologic therapy.

Influence of fiber on the phase transformations in the starch-water system

High-sensitivity, temperature-controlled DSC measurements at a low heating rate and creation of differential DSC traces scaled with respect to the reference material (completely dehydrated starch or completely dehydrated fiber, or their respective blends) permitted investigation of the influence of fiber on phase transformations in the wheat-starch-water system in the course of thermal gelatinization. Thermal effects associated with water interactions over the temperature range from 283 to 384 K under atmospheric pressure were determined. These thermal effects and previous structural studies permit us to make the following observations: (1) The main endothermic transition associated with melting of the crystalline part of the starch granule followed by a helix-coil transition in amylopectin occurs over the temperature range 319-333 K independent of the water and fiber contents. Adding fiber causes that transition to disappear both in the native blends and in water suspensions at low water contents. After adding more water and heating, recrystallization is observed and the transition reappears. (2) The fiber content has practically no influence on the slow exothermic transformation, which follows melting and helix-coil transition in amylopectin, proving that the slow transformation has a specific chemical character. In this reaction, the free ends of the unwound helices of amylopectin reassociate with parts of amylopectin molecules other than their original helix duplex partner, forming physical junctions and creating more general amorphous hydrogen bonded associations. (3) The high-temperature transition and small, but reproducible, distortions on the peaks of the main endothermic transition for water contents near 70-80 wt % are associated with smectic and nematic transitions, respectively. These are significantly influenced by the fiber content; higher fiber content causes an almost complete disappearance of these transitions. (4) The slow exothermic effect appearing almost from the very beginning of the heating in the starch-water system, associated with softening and uptake of water in the amorphous growth rings of the starch granule, is significantly hindered by added fiber.

Review article: nutrition and adult inflammatory bowel disease

Major advances in the understanding of the aetio-pathogenesis and genetics of inflammatory bowel disease have been accompanied by an escalation in the sophistication of immunomodulatory inflammatory bowel disease therapeutics. However, the basic 'triple' therapy (5-aminosalicylates, corticosteroids, azathioprine) and nutrition have maintained their central role in the management of patients with inflammatory bowel disease over recent decades. This review provides an overview of the supportive and therapeutic perspectives of nutrition in adult inflammatory bowel disease. The objective of supportive nutrition is to correct malnutrition in terms of calorie intake or specific macro- or micronutrients. Of particular clinical relevance is deficiency in calcium, vitamin D, folate, vitamin B12 and zinc. There is justifiably a growing sense of unease amongst clinicians and patients with regard to the long-term use of corticosteroids in inflammatory bowel disease. This, rather than arguments about efficacy, should be the catalyst for revisiting the use of enteral nutrition as primary treatment in Crohn's disease. Treatment failure is usually related to a failure to comply with enteral nutrition. Potential factors that militate against successful completion of enteral nutrition are feed palatability, inability to stay on a solid-free diet for weeks, social inconvenience and transient feed-related adverse reactions. Actions that can be taken to improve treatment outcome include the provision of good support from dietitians and clinicians for the duration of treatment and the subsequent 'weaning' period. There is evidence to support a gradual return to a normal diet through exclusion-re-introduction or other dietary regimen following the completion of enteral nutrition to increase remission rates. We also review the evidence for emerging therapies, such as glutamine, growth factors and short-chain fatty acids. The future may see the evolution of enteral nutrition into an important therapeutic strategy, and the design of a 'Crohn's disease-specific formulation' that is individually tailored, acceptable to patients, cost-effective, free from adverse side-effects and combines enteral nutrition with novel pre- and pro-biotics and other factors.

Clinical assessment of irritable bowel syndrome

Because irritable bowel syndrome (IBS) is a prevalent cause of visits to the gastroenterologist, it is extremely important to have accurate guidelines for the diagnosis. During the clinical assessment of IBS, the physician must look for the gastrointestinal symptoms, extraintestinal symptoms, and psychological history that are commonly associated with IBS. There are three diagnostic criteria that may be used in the IBS diagnosis: Manning, Rome I, and Rome II. Although there is discrepancy about which is most effective, we recommend that the Rome II be used in clinical practice. To confidently diagnose IBS, the physician must rule out organic disease as a cause of symptoms. This can be done by evaluating the patient's symptoms and screening for "red flags." The diagnostic strategy for IBS involves a thorough evaluation of the patient: taking a patient history, performing a physical exam, and performing the appropriate diagnostic tests when necessary.