Systematic review on the management of irritable bowel syndrome in North America

Effect of alverine citrate plus simethicone in colonoscopy: a randomized controlled trial

Colonoscopy is the standard procedure for screening, and surveillance of colorectal cancer, including the treatment for colonic lesions. Colonic spasm is an important problem from colonoscopy that affects both surgeons and patients. The spasm also might be the cause of longer cecal intubation time, difficulty of the procedure, and increased pain. Previous reports indicated that antispasmodic agents can decrease such symptoms. Therefore, we conducted this study to investigate the cecal intubation time of antispasmodic agents. A single blinded randomized controlled trial was conducted from 01/11/2020 to 31/08/2021. One hundred four patients were allocated to antispasmodic agent group and control group, in 1:1 ratio. The efficacy of median (range) cecal intubation time showed similar results of 5 (2, 14) and 5 (2, 15) minutes with no statistically significant difference. The mean scores of all domains i.e., pain, spasm, cleanliness, and difficulty were better in the antispasmodic agent group about 2.6 (1.4), 1.8 (0.8), 2.4 (0.9), and 2.0 (0.9), respectively, than control group but there were spasm and cleanliness showed statistically significant difference. Moreover, the satisfaction scores showed better efficacy in decreased spasm, decreased difficulty, and increased cleanliness than control group. Prescribing of antispasmodic drugs before colonoscopy might be the choice of treatment for the patients. The antispasmodic drugs will be beneficial to both of the patient and the doctor.

Efficacy and Mechanism of Trimebutine Maleate Combined with Lactulose in the Treatment of Constipation-Predominant Irritable Bowel Syndrome in the Elderly

Objective

Study on the efficacy and mechanism of trimebutine maleate combined with lactulose in the treatment of constipation-predominant irritable bowel syndrome (IBS-C) in the elderly.

Methods

From March 2019 to March 2021, 102 elderly patients with IBS-C were randomly divided into the observation group (51 cases) and the control group (51 cases). The observation group was treated with trimebutine maleate combined with lactulose, while the control group was treated with lactulose. Comparison of the clinical effects of the two groups. Comparison of vasoactive intestinal peptide (VIP) levels, neuropeptide Y (NPY) levels, and quality of life scores before and after treatment between the two groups. Documentation of adverse reactions during treatment.

Results

The improvement of clinical symptoms in the observation group was significantly better than that in the control group, and the difference is statistically significant (P < 0.05). The level of VIP after treatment in the observation group was significantly lower than that in the control group and before treatment, and the differences were statistically significant (P < 0.05). The level of NPY after treatment in the observation group was significantly higher than that in the control group and before treatment, and the differences were statistically significant (P < 0.05). The scores of dietary restrictions and health worries in the control group after treatment were significantly higher than those before treatment, and the differences were statistically significant (P < 0.05). The scores of anxious, behavioral conflict, dietary restrictions, health worries, social response, and family relationship in the observation group after treatment were significantly higher than those in the control group and before treatment, and the differences were statistically significant (P < 0.05). There were no serious adverse effects in either group during the treatment period, with some patients experiencing dizziness and dry mouth, which improved after discontinuation of the drug, without special intervention.

Conclusion

Trimebutine maleate combined with lactulose can improve clinical symptoms and quality of life in elderly patients with IBS-C, and its mechanism of action may be related to the regulation of the body's VIP and NPY levels.

Efficacy of pinaverium bromide in the treatment of irritable bowel syndrome: a systematic review and meta-analysis

BACKGROUND

Spasmolytic agents are an attractive first line treatment option for irritable bowel syndrome (IBS). Pinaverium bromide (pinaverium) has antispasmodic effects on gastrointestinal smooth muscle and can relieve major IBS symptoms, but an up-to-date meta-analysis comparing the efficacy of pinaverium with placebo is lacking. The aim is to perform a systematic review and meta-analysis to assess the efficacy of pinaverium compared with placebo for IBS treatment.

METHODS

All placebo-controlled trials evaluating pinaverium for IBS treatment were included, up to October 2019. Treatment efficacy was evaluated by overall patient IBS symptoms. Individual symptoms were also evaluated. The effect of pinaverium versus placebo was expressed as standardized mean difference (SMD) and risk ratio (RR). Odds ratio (OR) and number needed to treat (NNT) were also calculated.

RESULTS

Eight studies were included for analysis. Pinaverium treatment had a beneficial effect on overall IBS symptom relief with a positive SMD of 0.64 [95% confidence interval (CI) 0.45-0.82, p < 0.0001] and a positive RR of 1.75 (1.26-2.43, p < 0.0008). No significant difference was found by publication year, gender, age, methodological quality score (MQS), or sample size. No publication bias was detected. OR was 3.43 (2.00-5.88, p < 0.0001), and NNT was 4. Pinaverium also demonstrated a beneficial treatment effect for abdominal pain, stool change, and bloating improvement or resolution.

CONCLUSION

Pinaverium is superior to placebo for the treatment of IBS symptoms, irrespective of patient age or gender, study publication year, sample size, or MQS. The NNT in this meta-analysis is amongst the lowest for studies and meta-analyses of antispasmodics versus placebo in IBS.

Parasitic infections in irritable bowel syndrome patients: evidence to propose a possible link, based on a case-control study in the south of Iran

OBJECTIVES

The current study aimed to evaluate the prevalence of parasitic infections and their possible association with irritable bowel syndrome (IBS), through a case-control study. Stool samples were collected from patients with IBS and healthy subjects and were examined microscopically to detect intestinal parasites.

RESULTS

A total of 200 subjects were enrolled in the study including 100 patients with IBS and 100 healthy controls. The patients were selected based on the Rome III criteria. Of the 100 patients with IBS, 65 (65%) were female and 35 (35%) were male, with a mean age of 42.57 (± 4.07) years. Of these, 30 (30%) were infected with at least one intestinal parasite; the most common ones were Blastocystis hominis and Giardia lamblia. Of the control cases, 64 (64%) were female and 36 (36%) were male, with a mean age of 41.82 (± 11.75) years. Of these, 16 (16%) were infected with at least one intestinal parasite; the most common were B. hominis and Endolimax. There was a significant difference between the rate of parasitic infections between the patients with IBS and the control in particular, B. hominis and G. lamblia. The findings of the study support a possible link between parasitic infections and IBS.

Celiac Disease

Gluten-related disorders, including celiac disease, wheat allergy, and nonceliac gluten sensitivity (NCGS), are increasingly reported worldwide. Celiac disease is caused by an immune-mediated reaction to ingested gluten in genetically susceptible persons. NCGS is largely a diagnosis of exclusion when other causes of symptoms have been ruled out. All patients with celiac disease should be referred to a registered dietitian nutritionist with expertise in celiac disease and a gastroenterologist who specializes in celiac disease and malabsorptive disorders, and they should remain on a strict gluten-free diet indefinitely. This article provides an overview of gluten- and wheat-related disorders.

Antidepressants vs. Placebo for the Treatment of Functional Gastrointestinal Disorders in Adults: A Systematic Review and Meta-Analysis

Objective: To integrate high-quality evidence of the efficacy of antidepressants across different subtypes of functional gastrointestinal disorders (FGIDs). Methods: The Medline, PsycINFO, EMBASE, the Cochrane Library, and Chinese local database were searched up to October 1, 2017. Keywords included all subtypes of FGIDs, antidepressants, and randomized controlled trials (RCTs). We included RCTs with low to moderate risks of bias in comparing antidepressants with placebos as the only intervention in treating adult patients with FGIDs (PROSPERO ID: CRD42015030123). Language was restricted to English or Chinese. Data extraction was independently carried out by two authors, following the Cochrane Handbook for systematic reviews. Results: Of 2,460 records identified, 31 studies reporting on 2,340 participants were included in the meta-analysis. Antidepressants were more effective than placebos in terms of the rate of responder [RR = 1.35 (95% CI 1.12 to 1.63)], and the reduction of target gastrointestinal symptoms [SMD = -0.94 (95% CI -1.33 to -0.54)], and disability severity (moderate effect sizes). Those effects partly remained both at the presence and absence of comorbid depression, and among different subtypes of FGIDs. Subgroup analyses confirmed the benefit of tricyclic and tetracyclic antidepressants, selective serotonin reuptake inhibitors (SSRIs), and trazodone. Efficacy of serotonin and norepinephrine reuptake inhibitors (SNRIs), low doses of antidepressants, and antidepressants in intermediate to long term treatment was inconclusive due to the scarcity of eligible evidence. Compared to placebo, patients on antidepressants reported more adverse events [RR = 1.91 (95% CI 1.23 to 2.96)] and more frequent withdrawal. On average one in 7.4 (95% CI 5.4 to 11.9) patients treated with antidepressants responded, while one in 4.8 (95% CI 3.7 to 6.8) experienced certain adverse effects. Conclusions: Antidepressants were inferior to placebo in terms of tolerability and partly superior regarding efficacy. Before prescribing antidepressants, the benefits and side effects should be carefully evaluated.

Effect of Lactobacillus gasseri BNR17 on irritable bowel syndrome: a randomized, double-blind, placebo-controlled, dose-finding trial

Lactobacillus gasseri BNR17 is a strain isolated from human breast milk. The objective of this randomized, double-blind, placebo-controlled, and preliminary dose-finding trial was to find the effective dose and evaluate the effect of Lb. gasseri BNR17 on irritable bowel syndrome (IBS) symptoms. A total of 55 volunteers aged over 20 years with body mass index over 23 kg/m² were randomized to intake a placebo, low-dose (BNR-L, 2 × 10⁸ CFU/day), intermediate-dose (BNR-M, 2 × 10⁹ CFU/day), or high-dose BNR (BNR-H, 2 × 5 × 10⁹ CFU/day) for four weeks. Questionnaire for IBS symptoms scores and Lb. gasseri BNR17 in feces were assessed at the beginning and end of the trial. Among IBS symptoms scores, abdominal pain score was significantly reduced in BNR-H group. Lb. gasseri BNR17 was detected in all intake groups except placebo. In the preliminary study, Lb. gasseri BNR17 was confirmed to have probiotic properties.

Blastocystis subtypes isolated from irritable bowel syndrome patients and co-infection with Helicobacter pylori

Irritable bowel syndrome (IBS) is a chronic functional gastrointestinal disease presenting clinically by abdominal pain with alteration of bowel habits. Although IBS has uncertain etiology, chronic gut inflammation due to persistent exposure to an infectious agent including Blastocystis sp. was proposed. The aim of this study was to detect the prevalence of Blastocystis sp. subtype (ST) isolated from stool of IBS patients and to assess Blastocystis sp. and H. pylori co-infection in IBS patients from Beni-Suef Governorate, Egypt. Stool samples were collected from 115 IBS patients, following Rome III criteria. All stool samples were microscopically examined by wet mount and permanent trichrome stain, cultured on Jones' medium with further sequencing of positive Blastocystis isolates and screened for detection of H. pylori coproantigen. Blastocystis sp. was the predominant parasite in IBS patients; it had statistical significant association with both rural residence (OR = 10) and flatulence (OR = 8.2). There was a predominance of Blastocystis sp. ST3 (81%) followed by ST1 (19%). Blastocystis culture results (19.1%) were superior than microscopy (16.5%). The majority of Blastocystis-positive IBS patients (72.7%) were co-infected with H. pylori with statistical significance; however, H. pylori was higher in Blastocystis-negative IBS patients (47/64) than in Blastocystis-positive IBS patients (17/64). Interestingly, IBS is usually associated with gut dysbiosis, while the most prevalent parasite in our IBS patients was Blastocystis sp., which is frequently found in asymptomatic individuals. Whether Blastocystis sp. is a cause or a consequence of IBS still needs further investigation, with a particular focus on correlation of IBS with different Blastocystis sp. subtypes and gut microbiomes.

Mind-Body Interventions for Irritable Bowel Syndrome Patients in the Chinese Population: a Systematic Review and Meta-Analysis

PURPOSE

The aim of this study is to identify and assess evidence related to the efficacy of mind-body interventions on irritable bowel syndrome (IBS) in the Chinese population.

METHOD

Drawn from Chinese databases, nine RCTs and three Q-E studies were included in the systematic review. The methodological quality of RCTs was evaluated based on the following criteria: adequate sequence generation, allocation concealment, blinding, completeness of outcome data, selective reporting, and other potential biases. For continuous variables, the effect size (ES) was determined by calculating the standardized mean difference between groups. For dichotomous variables, the ES was determined by calculating the risk ratio (RR) between groups. Given the heterogeneity between the trials and the small number of studies included, both random effects and fixed effects models were used. The inverse variance method was used for pooling. Statistical analyses were performed using Review Manager version 5.0.

RESULTS

The total number of papers identified was 710: 462 from English language databases and 248 from Chinese language databases. Twelve studies met our eligibility criteria. Among the studies selected, three were Q-E studies the rest RCTs. Two studies described the randomization process. None of the studies reported allocation concealment nor blinding. Seven studies reported no dropouts. One of the studies mentioned the total amount of dropouts; though the reason for dropping out was not referenced. The other four studies did not clearly report dropouts. With the exception of three studies, there was inadequate information to determine biased reporting for the majority; the level of risk for bias in these studies is unclear. Finally, six meta-analyses were performed. One was conducted with four randomized controlled trials (RCTs) that used cure rate as outcome measures to evaluate gastrointestinal (GI) symptoms, which suggested that mind-body interventions were effective in improving GI symptoms (random effects model: RR = 1.08; 95 % CI 1.01 to 1.17; fixed effects model: RR = 1.07; 95 % CI 1.01 to 1.12). The remaining five were conducted in three RCTs, which suggested that mind-body interventions were effective in improving several aspects of quality of life, including interference with activity (random effects and fixed effects models: SMD = 0.64; 95 % CI 0.41 to 0.86), body image (random effects model: SMD = 0.36; 95 % CI 0.06 to 0.67; fixed effects model: SMD = 0.33; 95 % CI 0.11 to 0.55), health worry (random effects and fixed effects models: SMD = 0.67; 95 % CI 0.44 to 0.90), food avoidance (random effects and fixed effects models: SMD = 0.45; 95 % CI 0.23 to 0.68), and social reaction (random effects model: SMD = 0.79; 95 % CI 0.47 to 1.12; fixed effects model: SMD = 0.78; 95 % CI 0.55 to 1.01), as measured by Irritable Bowel Syndrome Quality of Life Questionnaire ( IBS-QOL).

CONCLUSION

Mind-body interventions may have the potential to improve GI symptoms in Chinese patients with IBS. The improvement of GI symptoms was also accompanied with the improvement of various outcomes, including depression, anxiety, and quality of life, just to mention a few. However, the published studies generally had significant methodological limitations. Future clinical trials with rigorous research design are needed in this field. More studies focusing on the mind-body interventions originated in China, such as tai chi and qi gong should be encouraged.

Association between self-reported vegetarian diet and the irritable bowel syndrome in the French NutriNet cohort

BACKGROUND

There is growing interest in using diet counselling in the management of patients with irritable bowel syndrome (IBS). Among new emerging diets, vegetarian diets (VD) seem to be experiencing an important popularity, partly because of their alleged health benefits. A recent study performed among a rural Indian population showed that predominant VD could be associated with IBS.

OBJECTIVE

This cross-sectional study aimed at assessing the association between the VD and IBS, among a large French cohort, the NutriNet-santé study.

METHODS

Subjects participating in the NutriNet-Santé cohort study completed a questionnaire based on Rome III criteria (N = 41,682). Anthropometrics, socio-demographical and lifestyle data, including VD, were collected prior to the completion of Rome III questionnaire via self-administered questionnaires. Association between VD and IBS and its subtypes was investigated through multivariate logistic regression.

RESULTS

The included subjects were mainly women (78.0%) and the mean age was 49.8±14.3 years. Among these individuals, 2,264 (5.4%) presented an IBS, and 805 (1.9%) reported a VD. Overall, VD was not associated with IBS or subtypes. A stable VD (i.e. self-declared at least three times) was associated with IBS (aOR 2.60 95%CI [1.37-4.91]), IBS mixed (aOR 2.97 95%CI [1.20-7.36]) and IBS diarrhoea (aOR 2.77 95%CI [1.01-7.59]).

CONCLUSIONS

This study suggests that a long term VD could be associated with IBS. Nevertheless, further studies are needed to confirm these results, and investigate the multiple aspects of the vegetarian diet, possibly related to the IBS.

Dietary patterns and prevalence of irritable bowel syndrome in Iranian adults

BACKGROUND

Although several dietary factors have been reported to alleviate or aggravate the symptoms of irritable bowel syndrome (IBS), no information is available linking habitual dietary patterns to irritable bowel syndrome.

OBJECTIVE

This study was undertaken to assess the association between dietary patterns and the risk of IBS among Iranian adults.

METHODS

In this cross-sectional study, data on 3846 Iranian adults working in 50 different health centers were examined. Dietary intake of study participants was assessed using a 106-item self-administered Dish-based Semi-quantitative Food Frequency Questionnaire (DS-FFQ) which was designed and validated specifically for Iranian adults. To identify major dietary patterns based on the 39 food groups, we used principal component analysis. A modified Persian version of the Rome III questionnaire was used for assessment of IBS.

RESULTS

We identified four major dietary patterns: (i) 'fast food', (ii) 'traditional', (iii) 'lacto-vegetarian', and (iv) 'western' dietary pattern. After adjustment for potential confounders, we found that those in the highest quartile of 'fast food' dietary pattern were tended to have higher risk of IBS than those in the lowest quartile (OR = 1.32; 95% CI: 0.99, 1.75, p_trend = 0.05). An inverse association was also found between 'lacto-vegetarian' dietary pattern and risk of IBS; such that even after adjustment for potential confounders, those in top quartile of this dietary pattern were 24% less likely to have IBS (0.76; 0.59, 0.98; p_trend = 0.02). No overall significant associations were observed between 'traditional' and 'western' dietary patterns and risk of IBS, either before or after adjustment for covariates.

CONCLUSION

We found that 'lacto-vegetarian' dietary pattern was associated with reduced risk, while 'fast food' dietary pattern was associated with a greater risk of IBS in Iranian adults.

Beliefs about GI medications and adherence to pharmacotherapy in functional GI disorder outpatients

OBJECTIVES

Pharmacotherapy is a mainstay in functional gastrointestinal (GI) disorder (FGID) management, but little is known about patient attitudes toward medication regimens. Understanding patient concerns and adherence to pharmacotherapy is particularly important for off-label medication use (e.g., antidepressants) in FGID.

METHODS

Consecutive tertiary GI outpatients completed the Beliefs About Medications questionnaire (BMQ). Subjects were categorized as FGID and structural GI disease (SGID) using clinician diagnoses and Rome criteria; GI-specific medications and doses were recorded, and adherence to medication regimens was determined by patient self-report. BMQ domains (overuse, harm, necessity, and concern) were compared between FGID and SGID, with an interest in how these beliefs affected medication adherence. Psychiatric measures (depression, anxiety, and somatization) were assessed to gauge their influence on medication beliefs.

RESULTS

A total of 536 subjects (mean age 54.7±0.7 years, range 22-100 years; n=406, 75.7% female) were enrolled over a 5.5-year interval: 341 (63.6%) with FGID (IBS, 64.8%; functional dyspepsia, 51.0%, ≥2 FGIDs, 38.7%) and 142 (26.5%) with SGID (IBD, 28.9%; GERD, 23.2%). PPIs (n=231, 47.8%), tricyclic antidepressants (TCAs) (n=167, 34.6%), and anxiolytics (n=122, 25.3%) were common medications prescribed. FGID and SGID were similar across all BMQ domains (P>0.05 for overuse, harm, necessity, and concern). SGID subjects had higher necessity-concern framework (NCF) scores compared with FGID subjects (P=0.043). FGID medication adherence correlated negatively with concerns about medication harm (r=-0.24, P<0.001) and overuse (r=-0.15, P=0.001), whereas higher NCF differences predicted medication compliance (P=0.006). Medication concern and overuse scores correlated with psychiatric comorbidity among FGID subjects (P<0.03 for each). FGID patients prescribed TCAs (n=142, 41.6%) expressed a greater medication necessity (17.4±0.4 vs. 16.2±0.4, P=0.024) and found their GI regimen to be more helpful (P=0.054). FGID subjects not on TCAs expressed a greater apprehension about medication overuse (10.7±0.3 vs. 9.7±0.2, P=0.002) on the BMQ.

CONCLUSIONS

FGID subjects report medication necessity and concern scores comparable to patients with SGID but have negative perceptions about medications, particularly in the presence of psychiatric comorbidity; these factors may affect treatment adherence and willingness to initiate neuromodulator regimens.

Blastocystis Isolates from Patients with Irritable Bowel Syndrome and from Asymptomatic Carriers Exhibit Similar Parasitological Loads, but Significantly Different Generation Times and Genetic Variability across Multiple Subtypes

Blastocystis spp is a common intestinal parasite of humans and animals that has been associated to the etiology of irritable bowel syndrome (IBS); however, some studies have not found this association. Furthermore, many biological features of Blastocystis are little known. The objective of present study was to assess the generation times of Blastocystis cultures, from IBS patients and from asymptomatic carriers. A total of 100 isolates were obtained from 50 IBS patients and from 50 asymptomatic carriers. Up to 50 mg of feces from each participant were cultured in Barret's and in Pavlova's media during 48 h. Initial and final parasitological load were measured by microscopy and by quantitative PCR. Amplicons were purified, sequenced and submitted to GenBank; sequences were analysed for genetic diversity and a Bayesian inference allowed identifying genetic subtypes (ST). Generation times for Blastocystis isolates in both media, based on microscopic measures and molecular assays, were calculated. The clinical symptoms of IBS patients and distribution of Blastocystis ST 1, 2 and 3 in both groups was comparable to previous reports. Interestingly, the group of cases showed scarce mean nucleotide diversity (π) as compared to the control group (0.011±0.016 and 0.118±0.177, respectively), whilst high gene flow and small genetic differentiation indexes between different ST were found. Besides, Tajima's D test showed negative values for ST1-ST3. No statistical differences regarding parasitological load between cases and controls in both media, as searched by microscopy and by qPCR, were detected except that parasites grew faster in Barret's than in Pavlova's medium. Interestingly, slow growth of isolates recovered from cases in comparison to those of controls was observed (p<0.05). We propose that generation times of Blastocystis might be easily affected by intestinal environmental changes due to IBS probably because virulent strains with slow growth may be selected, reducing their genetic variability.

Anxiety and depression comorbidities in irritable bowel syndrome (IBS): a systematic review and meta-analysis

Irritable bowel syndrome (IBS) has been associated with high prevalence of psychological disorders. However, it remains unclear whether IBS and each of its subtypes (predominant diarrhea IBS-D, constipation IBS-C, mixed IBS-M) are associated with higher anxiety and depressive symptoms levels. This study aimed to determine the associations of IBS and each of its subtypes with anxiety and/or depression. We conducted a systematic review and meta-analysis using five electronic databases (PubMed, PsychINFO, BIOSIS, Science Direct, and Cochrane CENTRAL). We selected case-control studies comparing anxiety and depression levels of patients with IBS to healthy controls, using standardized rating scales. Outcomes were measured as random pooled standardized mean differences (SMD). Ten studies were included in our analysis (885 patients and 1,384 healthy controls). Patients with IBS had significant higher anxiety and depression levels than controls (respectively, SMD = 0.76, 95 % CI 0.47; 0.69, p < 0.01, I2 = 81.7 % and SMD = 0.80, 95 % CI 0.42; 1.19, p < 0.01, I2 = 90.7 %). This significant difference was confirmed for patients with IBS-C and -D subtypes for anxiety, and only in IBS-D patients for depression. However, other IBS subtypes had a statistical trend to be associated with both anxiety and depressive symptomatology, which suggests a lack of power due to the small number of studies included. Patients with IBS had significantly higher levels of anxiety and depression than healthy controls. Anxiety and depression symptomatology should be systematically checked and treated in IBS patients, as psychological factors are important moderators of symptom severity, symptom persistence, decisions to seek treatment, and response to treatment.

Irritable bowel syndrome: Pathogenesis, diagnosis, treatment, and evidence-based medicine

Irritable bowel syndrome (IBS) is a chronic and debilitating functional gastrointestinal disorder that affects 9%-23% of the population across the world. The percentage of patients seeking health care related to IBS approaches 12% in primary care practices and is by far the largest subgroup seen in gastroenterology clinics. It has been well documented that these patients exhibit a poorer quality of life and utilize the health care system to a greater degree than patients without this diagnosis. The pathophysiology of IBS is not clear. Many theories have been put forward, but the exact cause of IBS is still uncertain. According to the updated ROME III criteria, IBS is a clinical diagnosis and presents as one of the three predominant subtypes: (1) IBS with constipation (IBS-C); (2) IBS with diarrhea (IBS-D); and (3) mixed IBS (IBS-M); former ROME definitions refer to IBS-M as alternating IBS (IBS-A). Across the IBS subtypes, the presentation of symptoms may vary among patients and change over time. Patients report the most distressing symptoms to be abdominal pain, straining, myalgias, urgency, bloating and feelings of serious illness. The complexity and diversity of IBS presentation makes treatment difficult. Although there are reviews and guidelines for treating IBS, they focus on the efficacy of medications for IBS symptoms using high-priority endpoints, leaving those of lower priority largely unreported. Therefore, the aim of this review is to provide a comprehensive evidence-based review of the diagnosis, pathogenesis and treatment to guide clinicians diagnosing and treating their patients.

Irritable bowel syndrome: a review and update

The understanding of irritable bowel syndrome (IBS) has undergone a rapid evolution with scientific advancement. IBS is a common functional bowel disorder that generates a significant health care burden and is the most commonly diagnosed gastrointestinal condition. There are well-established diagnostic criteria and algorithms for the initial evaluation of patients presenting with the symptoms of IBS. The symptoms can be targeted for therapy with a variety of pharmaceutical and nonpharmaceutical agents. Therapy should be individualized for the patient, and the cornerstone for any effective treatment strategy should be the solid patient-physician relationship.

IBS and the role of otilonium bromide

INTRODUCTION

Awareness of the seriousness of irritable bowel disorder (IBS) remains low among clinicians. In this review, we summarize the current knowledge of IBS and highlight the major personal, economic, and social burden of the disease, and the importance of adequate treatment of what is still often viewed as a trivial disorder. In fact, IBS is a major reason for referral.

PATHOPHYSIOLOGY

It is crucial that the varied pathophysiologies of this complex heterogeneous disease are understood in order to be able to treat both the presenting symptoms (pain, bloating, flatulence, abnormal defecation, diarrhea, constipation) and the underlying disorder effectively. Low-grade inflammatory and immune activation has been observed, but the precise triggers and mechanisms, and the relevance to symptom generation, remain to be established.

TREATMENT

IBS patients require different treatment strategies according to the pattern, severity, frequency, and symptoms. While initial therapy traditionally targets the most bothersome symptom, long-term therapy aims at maintaining symptom control and preventing recurrence. In addition to dietary/lifestyle interventions and psychosocial strategies, a wide range of pharmacologic therapies are approved for use in IBS depending on the symptoms reported. Musculotropic spasmolytics, which act directly on intestinal smooth muscle contractility, such as otilonium bromide, are effective, particularly in the relief of abdominal pain and bloating, and are well tolerated in IBS. THE OBIS TRIAL: The recent large placebo-controlled Otilonium Bromide in Irritable Bowel Syndrome study demonstrated the superiority of otilonium bromide versus placebo not only in the reduction of pain and bloating, but also in protection from relapse due to the long-lasting effect.

Long-term efficacy and safety of ramosetron in the treatment of diarrhea-predominant irritable bowel syndrome

Irritable bowel syndrome (IBS) is a functional disease with persisting gastrointestinal symptoms that has been classified into four subtypes. Serotonin (5-hydroxytryptamine [5-HT]) plays important physiological roles in the contraction and relaxation of smooth muscle. Intraluminal distension of the intestine is known to stimulate the release of endogenous 5-HT from enterochromaffin cells, activating 5-HT3 receptors located on primary afferent neurons and leading to increases in intestinal secretions and peristaltic activity. Ramosetron, a potent and selective 5-HT3-receptor antagonist, has been in development for use in patients suffering from diarrhea-predominant IBS. In a double-blind, placebo-controlled, parallel-group study of 418 patients with diarrhea-predominant IBS-D, once-daily 5 μg and 10 μg doses of ramosetron increased the monthly responder rates of IBS symptoms compared to placebo. In a 12-week randomized controlled trial of 539 patients, a positive response to treatment was reported by 47% of a once-daily 5 μg dose of ramosetron-treated individuals compared to 27% of patients receiving placebo (P<0.001). Furthermore, the responder rate was increased in the oral administration of 5 μg of ramosetron for at least 28 weeks (up to 52 weeks), and long-term efficacy for overall improvement of IBS symptoms was also demonstrated. The rate was further increased subsequently. Adverse events were reported by 7% in ramosetron treatment. No serious adverse events, eg, severe constipation or ischemic colitis, were reported for long-term treatment with ramosetron. In conclusion, further studies to evaluate the long-term efficacy and safety of ramosetron are warranted in the form of randomized controlled trials.

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.

Treatment of functional diarrhea

Functional diarrhea (FD), one of the functional gastrointestinal disorders, is characterized by chronic or recurrent diarrhea not explained by structural or biochemical abnormalities. The treatment of FD is intimately associated with establishing the correct diagnosis. First, FD needs to be distinguished from diarrhea-predominant irritable bowel syndrome (IBS), in which, unlike in FD, abdominal pain is a primary diagnostic criterion. Next, FD must be differentiated from the myriad organic causes of chronic diarrhea. Unlike IBS, in which a positive diagnosis can be made with an acceptable level of confidence using symptom-based criteria and minimal testing, the diagnosis of FD is still primarily a diagnosis of exclusion. Thus, the onus is on the physician to eliminate potential underlying causes, both common and uncommon, in the proper clinical setting. Once the diagnosis has been established, the clinician and patient should first focus on identifying, eliminating, and/or treating aggravating factors. These may include physiologic factors (eg, small bowel bacterial overgrowth), psychological factors (eg, stress and anxiety), and dietary factors (eg, carbohydrate malabsorption). Thereafter, appropriate treatment for functional diarrhea may be instituted. Treatment options include dietary and lifestyle modification, pharmacologic therapies, and alternative modalities. Although many of these strategies have been studied in IBS, almost none of them has been examined specifically in FD. Furthermore, given the poorly understood pathophysiologic basis of FD, these treatments primarily target a patient's symptoms and presumed altered physiology rather than underlying etiologic mechanisms. Therefore, we stress that treatment must be approached in an individualized manner and that dietary and pharmacologic therapies should be part of a comprehensive therapeutic approach in which education and reassurance form the foundation. In general, we attempt to remove dietary triggers and recommend increased fiber intake. We then add anticholinergic, antispasmodic, antimotility, and antidiarrheal agents as the first line of pharmacotherapy. Should a patient not respond to these, and for patients who have a significant degree of psychological dysfunction, central acting agents, including antidepressants and/or anxiolytics, may be beneficial. During the treatment period, we also recommend that physicians keep an open mind. If signs or symptoms that suggest an ongoing or previously unrecognized organic process develop, then a re-evaluation of the clinical picture is indicated.

Increased risk of miscarriage and ectopic pregnancy among women with irritable bowel syndrome

BACKGROUND & AIMS

Irritable bowel syndrome (IBS) is the most commonly diagnosed gastrointestinal condition and is most prevalent in women of reproductive age. We investigated the effects of IBS on risk for adverse outcomes from pregnancy.

METHODS

We conducted a cohort study by using the United Kingdom General Practice Research Database. The study cohort consisted of 100,000 women selected by stratified random sampling from all women with a diagnosis of pregnancy from January 1, 1990, to December 31, 2008. Those with a recorded diagnosis of IBS before pregnancy were identified (n = 26,543). Outcome measures were spontaneous miscarriage, ectopic pregnancy, preeclampsia, and stillbirth. Odds ratios (ORs) and 95% confidence intervals (CIs) for the association between IBS and pregnancy outcomes were estimated by using logistic regression adjusted for several potential confounders.

RESULTS

Of women diagnosed with IBS before pregnancy, 6578 (7%) had a spontaneous miscarriage, 741 (0.74%) had an ectopic pregnancy, 425 (0.43%) developed preeclampsia, and 217 (0.22%) had a stillbirth. Maternal IBS was associated with a moderately increased risk of miscarriage (OR, 1.21; 95% CI, 1.13-1.30) and ectopic pregnancy (OR, 1.28%; 95% CI, 1.06-1.55). There did not appear to be an association between IBS and preeclampsia (OR, 1.09; 95% CI, 0.85-1.39) or stillbirth (OR, 1.00; 95% CI, 0.69-1.44).

CONCLUSIONS

IBS, a common disorder in women of reproductive age, appears to increase the risk of miscarriage and ectopic pregnancy. These findings indicate the importance of prenatal care for women with IBS.

The shortcomings of clinical trials assessing the efficacy of probiotics in irritable bowel syndrome

BACKGROUND

Multiple clinical trials within the past decade have aimed to study the safety and efficacy of various probiotic strains in treating patients with irritable bowel syndrome (IBS). However, there exists much heterogenicity in study design among these trials, namely, in bacterial strain, dose, dosage form, sample size, study duration, and population demographics.

AIM

The aim of this study was to identify the shortcomings of clinical trials using probiotic treatments in subjects with IBS, so that researchers may realize where limitations exist, allowing them to curtail these limitations in future trials.

METHODS

An extensive PubMed search was conducted using the following keywords: probiotics in irritable bowel syndrome, probiotic pharmacokinetics, Lactobacillus, Bifidobacterium, Alosetron, Tegaserod, Alosetron, and Tegaserod safety profile. A total of 62 articles were used in constructing this review, with 20 original articles.

RESULTS

Stark differences in study design existed among the 20 original articles analyzed, as well as an outstandingly high "placebo effect," making the ability to compare these articles as a means for evidence-based treatment therapy in IBS very difficult.

CONCLUSIONS

Future large, randomized, double-blind, placebo-controlled clinical trials must be conducted, embodying minimal variability in study designs, to appropriately assess the efficacy of specific probiotic strains over placebo.

Visceral sensitivity as a mediator of outcome in the treatment of irritable bowel syndrome

Patients with irritable bowel syndrome (IBS) experience anxiety about visceral sensations, leading to avoidance behaviors and hypervigilance that maintain IBS symptoms. The current study used data from a clinical trial that compared a treatment aimed at reducing anxiety about visceral sensations (interoceptive exposure; IE) to an attention control (AC) and a CBT-based stress-management treatment (SM) to examine whether changes in visceral sensitivity mediated IBS symptom and quality of life outcomes. Data from participants who completed one of the three treatments (N = 76) were subjected to mediation analyses. Visceral sensitivity mediated treatment outcomes across all outcome measures and across all treatment groups, with no differences between IE and the other treatment groups. This finding suggests that psychosocial treatments for IBS may work by decreasing visceral sensitivity, and the degree to which visceral sensitivity is decreased is related to outcome, suggesting IE may be the preferable treatment option.

Efficacy and safety profile of LCR35 complete freeze-dried culture in irritable bowel syndrome: A randomized, double-blind study

AIM: To assess the effects and safety of Lactobacillus casei rhamnosus LCR35 complete freeze-dried culture (LCR35) in patients suffering from irritable bowel syndrome (IBS).

METHODS: A randomized, double-blind pilot study was performed in 50 patients complaining of IBS symptoms complying with Rome III criteria. Patients were allocated to receive either LCR35 (n = 25) at a minimum daily dose of 6 × 10⁸ colony forming units or placebo (n = 25) for 4 wk. At inclusion, after treatment and 2 wk later, patients completed the IBS severity scale. Change from baseline in the IBS severity score at the end of treatment was the primary efficacy criterion. Changes were compared between groups in the whole population and in IBS subtypes (IBS with predominance of constipation, IBS with predominance of diarrhoea, mixed IBS, unsubtyped IBS). The presence of lactobacillus casei rhamnosus in stools was investigated at inclusion and at the end of treatment. The gastrointestinal quality of life questionnaire and the hospital anxiety and depression (HAD) scale were also completed.

RESULTS: Both groups were balanced for baseline characteristics. In 85% of patients, stool analyses showed that lactobacillus casei rhamnosus able to survive in the digestive tract. In the whole population, improvements in the IBS severity score did not differ significantly between treatments with a 25% decrease after 4-wk treatment, and a 15% decrease from baseline 2 wk later in both groups. In IBS subgroups, statistical analysis could not be performed due to small sample size, but a clinical response in favour of LCR35 was observed in IBS patients with predominance of diarrhoea: no change in the symptom severity score was seen with the placebo after 4 wk treatment, whereas a clinically relevant decrease occurred with LCR35 (-37% vs -3%). Furthermore, in spite of an increase in symptom intensity, the IBS severity score was maintained below the baseline value 2 wk later with LCR35 (-19% from baseline), whilst a slight 5% increase from baseline was observed with placebo. In the IBS subgroup with predominance of diarrhoea only, a clinically relevant decrease in abdominal pain severity score (-36%) was observed with LCR35, whereas no change occurred with placebo. In mixed IBS patients, the 20% and 30% decreases in the IBS severity score observed after treatment with LCR35 and placebo, respectively, were maintained 2 wk later in both groups. A clinical response slightly in favour of placebo was observed at the end of the treatment period in IBS patients with predominance of constipation (-41% vs -20%) and unsubtyped IBS patients (-47% vs -17%), with the same value maintained 2 wk later. In both groups, no clinically relevant changes were observed either for the gastrointestinal quality of life index or HAD score. Thus, these results suggest that sub-grouping of IBS patients may be important for optimizing treatment responses by the physician.

CONCLUSION: This pilot study suggests that LCR35 could have some efficacy in IBS patients complaining of diarrhoea. These preliminary results need to be confirmed in larger studies.

Complementary and alternative medicine used by persons with functional gastrointestinal disorders to alleviate symptom distress

AIM

The aim of this study was to describe the complementary and alternative medicine methods most commonly used to alleviate symptom distress in persons with functional gastrointestinal disorders.

BACKGROUND

People with functional gastrointestinal disorders face many challenges in their everyday lives, and each individual has his/her own way of dealing with this illness. The experience of illness often leads persons with functional gastrointestinal disorders to complementary and alternative medicine as a viable healthcare choice.

DESIGN

Quantitative and describing design.

METHOD

A study-specific complementary and alternative medicine questionnaire was used, including questions about complementary and alternative medicine methods used and the perceived effects of each method. Efficacy assessments for each method were preventive effect, partial symptom relief, total symptom relief or no effect.

RESULTS

A total of 137 persons with functional gastrointestinal disorders answered the questionnaire, 62% (n = 85) women and 38% (n = 52) men. A total of 28 different complementary and alternative medicine methods were identified and grouped into four categories: nutritional, drug/biological, psychological activity and physical activity. All persons had tried at least one method, and most methods provided partial symptom relief.

CONCLUSION

Persons with functional gastrointestinal disorders commonly use complementary and alternative medicine methods to alleviate symptoms. Nurses have a unique opportunity to expand their roles in this group of patients.

RELEVANCE TO CLINICAL PRACTICE

Increased knowledge of complementary and alternative medicine practices would enable a more comprehensive patient assessment and a better plan for meaningful interventions that meet the needs of individual patients.

Colonic butyrate- algesic or analgesic?

Irritable bowel syndrome (IBS) is a common health issue that is characterized by abdominal pain, abnormal bowel movements, and altered visceral perception. The complexity and variability in symptoms pose serious challenges in treating IBS. Current therapy for IBS is primarily focused on reducing the abdominal pain, thereby improving the quality of life to a significant extent. Although the use of fiber rich diet is widely recommended in treating IBS, some studies have questioned its use. Intra-colonic butyrate, a short-chain fatty acid, is primarily produced by the fermentation of dietary fibers in the colon. In the existing literature there are conflicting reports about the function of butyrate. In rats it is known to induce visceral hypersensitivity without altered pathology, whereas in humans it has been reported to reduce visceral pain. Understanding the molecular mechanisms responsible for this contrasting effect of butyrate is important before recommending fiber rich diet to IBS patients.

Physicians and patients measure different dimension on assessment for gastroesophageal reflux disease-related symptoms [corrected]

Background/Aims

Gastroesophageal reflux disease is a highly prevalent disease. Assessing treatment efficacy is critical in that clinical endpoints are properly evaluated. Clinical tools for symptoms severity assessment should be discriminative, predictive and evaluative.

Methods

In this study we compared a patient-oriented symptoms evaluation (ReQuest™) vs a structured interview assessment initiated by a physician (sickness impact profile [SIP]). Both questionnaires were analyzed in a multidimensional space using latent factors. Five dimensions were found: 1 for the short ReQuest™ questionnaire and 4 for SIP.

Results

We included 1,522 women and 1,296 men; mean age was 36 ± 7 years, and mean body mass index was 26 ± 4. The score questionnaire assessment evaluation by physicians and patients did not correlate between them (between r = 0.03 and 0.26) except nausea and sleep disorder (r = 0.45 and 0.51) but both were sensitive enough to detect changes after treatment (P < 0.05). Medical specialty of the physician showed effect on the score of both, ReQuest™ and SIP evaluation. Questionnaire variance decomposition due to specialist was only 2% (P < 0.05).

Conclusions

While both evaluations are orthogonal (non-correlated), meaning patients and physicians measured diverse aspects of the same disease, they both were able to measure patient's improvement with treatment.

Probiotics for the control of parasites: an overview

Probiotics are defined as live organisms, which confer benefits to the host. Their efficiency was demonstrated for the treatment of gastrointestinal disorders, respiratory infections, and allergic symptoms, but their use is mostly limited to bacterial and viral diseases. During the last decade, probiotics as means for the control of parasite infections were reported covering mainly intestinal diseases but also some nongut infections, that are all of human and veterinary importance. In most cases, evidence for a beneficial effect was obtained by studies using animal models. In a few cases, cellular interactions between probiotics and pathogens or relevant host cells were also investigated using in vitro culture systems. However, molecular mechanisms mediating the beneficial effects are as yet poorly understood. These studies indicate that probiotics might indeed provide a strain-specific protection against parasites, probably through multiple mechanisms. But more unravelling studies are needed to justify probiotic utilisation in therapeutics.

Male accessory gland infection frequency in infertile patients with chronic microbial prostatitis and irritable bowel syndrome

Recently, we reported an increased prevalence of chronic bacterial prostatitis (CBP) in patients with prostatitis syndromes (PS) and irritable bowel syndrome (IBS) compared with patients with PS alone. The aim of this study was to evaluate the frequency of male accessory gland infections (MAGI) in patients with CBP plus IBS and to compare the sperm parameters of patients with or without MAGI. Fifty consecutive patients with the following criteria were enrolled: (i) infertility; (ii) diagnosis of CBP; and (iii) diagnosis of IBS according to the Rome III criteria. The following two aged-matched control groups were also studied: infertile patients with CBP alone (n = 56) and fertile men (n = 30) who fathered a child within the previous 3 months. Patients and controls underwent to an accurate anamnesis, administration of the NIH-Chronic Prostatitis Symptom Index (NIH-CPSI) and the Rome III questionnaires for prostatitis and IBS, respectively, physical examination, and semen analysis. A significantly higher frequency of MAGI was found in patients with CBP plus IBS (82.0%) compared with the patients with CBP alone (53.6%) or the fertile men (0%). The presence of MAGI in the patients with CBP plus IBS was associated with a significantly lower sperm concentration, total number, and forward motility, and with a higher seminal leucocyte concentration compared with the patients with CBP alone and MAGI. Sperm normal morphology was similar in the groups of patients. All sperm parameters did not differ significantly in both the groups of patients without MAGI. The patients with CBP plus IBS had a significantly higher frequency of MAGI compared with the patients with CBP alone. This was associated with worse sperm parameters and, hence, poorer reproductive prognosis. We suggest to search for the presence of IBS in the patients with PS and in particular when CBP and/or worse sperm parameters are present.

Lessons Learnt from Post-Infectious IBS

The development of IBS symptoms – altered bowel function and abdominal cramping in a subset of adult subjects exposed to severe enteric infections opened up an unprecedented opportunity to understand the etiology of this poorly understood disorder. Perhaps, for the reasons that these symptoms follow a severe enteric infection, and mucosal biopsy tissues are readily available, the focus of most studies thus far has been to show that mild/low-grade mucosal inflammation persisting after the initial infection has subsided causes the IBS symptoms. Parallel studies in non-infectious IBS patients, who did not have prior enteritis, showed similar mild mucosal inflammation. Together, these studies examined the mucosal infiltration of specific immune cells, increase of select inflammatory mediators, mast cell and enterochromaffin cell hyperplasia, and epithelial permeability. In spite of the fact that the data on these topics were not consistent among different studies and clinical trials with prednisone, fluoxetine, and ketotifen failed to provide relief of IBS symptoms, the predominant conclusions were that mild mucosal inflammation is the cause of IBS symptoms. However, the circular smooth muscle cells, and myenteric neurons are the primary regulators of gut motility function, while primary afferent neurons and CNS play essential roles in induction of visceral hypersensitivity – no explanation was provided as to how mild mucosal inflammation causes dysfunction in cells far removed. Accumulating evidence shows that mild mucosal inflammation in IBS patients is in physiological range. It has little deleterious effects on cells within its own environment and therefore it is unlikely to affect cells in the muscularis externa. This review discusses the disconnect between the focus on mild/low-grade mucosal inflammation and the potential mechanisms and molecular dysfunctions in smooth muscle cells, myenteric neurons, and primary afferent neurons that may underlie IBS symptoms.

Lessons Learnt from Post-Infectious IBS

The development of IBS symptoms - altered bowel function and abdominal cramping in a subset of adult subjects exposed to severe enteric infections opened up an unprecedented opportunity to understand the etiology of this poorly understood disorder. Perhaps, for the reasons that these symptoms follow a severe enteric infection, and mucosal biopsy tissues are readily available, the focus of most studies thus far has been to show that mild/low-grade mucosal inflammation persisting after the initial infection has subsided causes the IBS symptoms. Parallel studies in non-infectious IBS patients, who did not have prior enteritis, showed similar mild mucosal inflammation. Together, these studies examined the mucosal infiltration of specific immune cells, increase of select inflammatory mediators, mast cell and enterochromaffin cell hyperplasia, and epithelial permeability. In spite of the fact that the data on these topics were not consistent among different studies and clinical trials with prednisone, fluoxetine, and ketotifen failed to provide relief of IBS symptoms, the predominant conclusions were that mild mucosal inflammation is the cause of IBS symptoms. However, the circular smooth muscle cells, and myenteric neurons are the primary regulators of gut motility function, while primary afferent neurons and CNS play essential roles in induction of visceral hypersensitivity - no explanation was provided as to how mild mucosal inflammation causes dysfunction in cells far removed. Accumulating evidence shows that mild mucosal inflammation in IBS patients is in physiological range. It has little deleterious effects on cells within its own environment and therefore it is unlikely to affect cells in the muscularis externa. This review discusses the disconnect between the focus on mild/low-grade mucosal inflammation and the potential mechanisms and molecular dysfunctions in smooth muscle cells, myenteric neurons, and primary afferent neurons that may underlie IBS symptoms.

Association of participation in a mindfulness programme with bowel symptoms, gastrointestinal symptom-specific anxiety and quality of life

BACKGROUND

Stress perception and GI-specific anxiety play key roles in irritable bowel syndrome (IBS). Mindfulness-based stress reduction (MBSR) is a widely available stress reduction course, which has not been evaluated for IBS.

AIM

To determine whether participation in MBSR is associated with improvement in bowel symptoms, GI-specific anxiety, and IBS-Quality of Life.

METHODS

This is a prospective study of 93 participants in MBSR. We applied measures of Rome III IBS status, bowel symptoms (IBS-Severity Scoring System, IBS-SSS), IBS-Quality of Life (IBS-QOL), GI-specific anxiety (Visceral Sensitivity Index, VSI), mindfulness (Five Facet Mindfulness Questionnaire-FFMQ), and functional status (SF-8) at baseline and 2 and 6 months after enrolment.

RESULTS

At 2 months, participation in MBSR was associated with small nonsignificant changes in IBS-SSS, IBS-QOL and VSI: d = -0.25, d = 0.08, d = -0.16, respectively. At 6 months, there was no significant change in IBS-SSS (d = -0.36); whereas for IBS-QOL and VSI there were significant improvements (IBS-QOL: d = 0.33, P = 0.044; VSI: d = -0.40, P = 0.014). For patients meeting Rome III IBS criteria (n = 43), changes in IBS-SSS, IBS-QOL and VSI were not statistically significant, but there was a significant correlation between the change in VSI and the change in FFMQ across the three time periods (r = 0.33).

CONCLUSIONS

Participation in MBSR is associated with improvement IBS-related quality of life and GI-specific anxiety. Randomised controlled trials are warranted to further assess the role of MBSR for IBS symptomatology.

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.

A cognitive-behavioral treatment for irritable bowel syndrome using interoceptive exposure to visceral sensations

BACKGROUND

Irritable bowel syndrome (IBS) is a chronic and debilitating medical condition with few efficacious pharmacological or psychosocial treatment options available. Evidence suggests that visceral anxiety may be implicated in IBS onset and severity. Thus, cognitive-behavioral treatment (CBT) that targets visceral anxiety may alleviate IBS symptoms.

METHODS

The current study examined the efficacy of a CBT protocol for the treatment of IBS which directly targeted visceral sensations. Participants (N = 110) were randomized to receive 10 sessions of either: (a) CBT with interoceptive exposure (IE) to visceral sensations; (b) stress management (SM); or (c) an attention control (AC), and were assessed at baseline, mid-treatment, post-treatment, and follow-up sessions.

RESULTS

Consistent with hypotheses, the IE group outperformed AC on several indices of outcome, and outperformed SM in some domains. No differences were observed between SM and AC. The results suggest that IE may be a particularly efficacious treatment for IBS.

CONCLUSIONS

Implications for research and clinical practice are discussed.

Comparison of symptom response following advice for a diet low in fermentable carbohydrates (FODMAPs) versus standard dietary advice in patients with irritable bowel syndrome

BACKGROUND

Emerging evidence indicates that the consumption of fermentable oligosaccharides, disaccharides, monosaccharides and polyols (FODMAPs) may result in symptoms in some patients with irritable bowel syndrome (IBS). The present study aimed to determine whether a low FODMAP diet is effective for symptom control in patients with IBS and to compare its effects with those of standard dietary advice based on the UK National Institute for Health and Clinical Excellence (NICE) guidelines.

METHODS

Consecutive patients with IBS who attended a follow-up dietetic outpatient visit for dietary management of their symptoms were included. Questionnaires were completed for patients who received standard (n = 39) or low FODMAP dietary advice (n = 43). Data were recorded on symptom change and comparisons were made between groups.

RESULTS

In total, more patients in the low FODMAP group reported satisfaction with their symptom response (76%) compared to the standard group (54%, P = 0.038). Composite symptom score data showed better overall symptom response in the low FODMAP group (86%) compared to the standard group (49%, P < 0.001). Significantly more patients in the low FODMAP group compared to the standard group reported improvements in bloating (low FODMAP 82% versus standard 49%, P = 0.002), abdominal pain (low FODMAP 85% versus standard 61%, P = 0.023) and flatulence (low FODMAP 87% versus standard 50%, P = 0.001).

CONCLUSIONS

A low FODMAP diet appears to be more effective than standard dietary advice for symptom control in IBS.

A cognitive-behavioral treatment for irritable bowel syndrome using interoceptive exposure to visceral sensations

BACKGROUND

Irritable bowel syndrome (IBS) is a chronic and debilitating medical condition with few efficacious pharmacological or psychosocial treatment options available. Evidence suggests that visceral anxiety may be implicated in IBS onset and severity. Thus, cognitive-behavioral treatment (CBT) that targets visceral anxiety may alleviate IBS symptoms.

METHODS

The current study examined the efficacy of a CBT protocol for the treatment of IBS which directly targeted visceral sensations. Participants (N = 110) were randomized to receive 10 sessions of either: (a) CBT with interoceptive exposure (IE) to visceral sensations; (b) stress management (SM); or (c) an attention control (AC), and were assessed at baseline, mid-treatment, post-treatment, and follow-up sessions.

RESULTS

Consistent with hypotheses, the IE group outperformed AC on several indices of outcome, and outperformed SM in some domains. No differences were observed between SM and AC. The results suggest that IE may be a particularly efficacious treatment for IBS.

CONCLUSIONS

Implications for research and clinical practice are discussed.

High frequency of chronic bacterial and non-inflammatory prostatitis in infertile patients with prostatitis syndrome plus irritable bowel syndrome

BACKGROUND

Although prostatitis syndrome (PS) and irritable bowel syndrome (IBS) are common disorders, information on the prevalence of IBS in infertile patients with PS is relatively scanty. Therefore, this study was undertaken to estimate the frequency of PS and IBS and to evaluate the prevalence of the various diagnostic categories of prostatitis.

METHODOLOGY/PRINCIPAL FINDINGS

This study enrolled 152 patients with PS, diagnosed by the NIH-Chronic Prostatitis Symptom Index (NIH-CPSI) in an andrological setting, and 204 patients with IBS, diagnosed according to the Rome III diagnostic criteria in a gastroenterological setting. The patients with PS were asked to fulfill the Rome III questionnaire for IBS, whereas patients with IBS were asked to complete the NIH-CPSI. The simultaneous presence of PS and IBS was observed in 30.2% and 31.8% of the patients screened by andrologists and gastroenterologists, respectively. Altogether, 111 patients had PS plus IBS (31.2%). They had a total NIH-CPSI and pain subscale scores significantly higher than patients with PS alone. Gastrointestinal symptoms in patients with PS plus IBS were similar to those reported by patients with IBS alone and significantly greater in patients with PS alone. Patients with PS plus IBS had a significantly higher frequency of chronic bacterial prostatitis (category II) and lower of non-inflammatory prostatitis (category IIIB), compared to patients with PS alone. The frequency of inflammatory prostatitis (category IIIA) resulted similar.

CONCLUSIONS/SIGNIFICANCE

Prostatitis syndromes and IBS are frequently associated in patients with PS- or IBS-related symptoms. These patients have an increased prevalence of chronic bacterial and non-inflammatory prostatitis.

Investigational agents for the irritable bowel syndrome

IMPORTANCE OF THE FIELD

Irritable bowel syndrome (IBS) is a common disorder with significant health and economic consequences. The etiology of IBS is complex and appears to be multifactorial. Traditional IBS therapies have been directed primarily at the relief of individual symptoms but have been largely disappointing. This has triggered the search for newer treatment strategies with improved patient outcomes.

AREAS COVERED IN THIS REVIEW

Enhanced knowledge about the putative pathophysiology of IBS has allowed the identification of new mechanistic targets for treatment. Our aim is to review emerging and promising drugs in the treatment of IBS based on disease pathophysiology. Data were extracted using Medline and PubMed search engines until January 2010. Abstracts were identified through 'Web of Science' and abstract supplements of major gastrointestinal scientific meetings. Drugs were classified according to mechanism of action and those with efficacy in trials involving human subjects examined.

WHAT THE READER WILL GAIN

Additional insight into the pathophysiology as well as current and prospective treatments of IBS.

TAKE HOME MESSAGE

A multitude of putative drug targets have been identified and some novel treatments have progressed through to human clinical trials, but very few will be approved for the market in the near future. Moreover, and in keeping with the complex and multifactorial nature of this syndrome, it is unlikely that there will be one dominant and universally effective form of therapy for all IBS patients.

Ameliorating effects of mirtazapine on visceral hypersensitivity in rats with neonatal colon sensitivity

BACKGROUND

The aim was to investigate the effects of mirtazapine on visceral hypersensitivity and gastric emptying in an established rodent model of colonic sensitization.

METHODS

Twenty colonic sensitized rats and 20 matched controls were used. Visceral sensitivity during colorectal distension (CRD) was assessed by the measurement of abdominal electromyogram (EMG) with the pressures of 20, 40, and 60 mmHg. Mirtazapine with doses of 1, 5, and 10 mg kg(-1) were administered orally. Gastric emptying and small intestinal transit were performed in a separated experiment after gavage of 1.5 mL of phenol red solution.

KEY RESULTS

(i) Visceral hypersensitivity after neonatal colonic sensitization was confirmed. (ii) Mirtazapine dose-dependently reduced visceral hypersensitivity in the colonic sensitized rats. The increases in EMG during CRD at 40, 60 mmHg were, 17.59 +/- 6.49 and 26.04 +/- 8.30, respectively, with saline session, and substantially reduced to 10.0 +/- 5.95 (P = 0.02 vs corresponding saline) and 12.58 +/- 7.43 (P < 0.001 vs saline) with mirtazapine at 10 mg kg(-1). Similar findings were noted at doses of 5 and 1 mg kg(-1) at a lesser degree. In the control rats, mirtazapine-reduced visceral sensitivity only during CRD at 60 mmHg. (iii) Mirtazapine 10 mg kg(-1) significantly accelerated gastric emptying (P = 0.045) but slightly and marginally delayed intestinal transit (P = 0.058) the colonic sensitized rats.

CONCLUSIONS & INFERENCES

Mirtazapine dose-dependently ameliorates visceral hypersensitivity in colonic sensitized rats. Mirtazapine at a high dose improves delayed gastric emptying in colonic sensitized rats but slightly and marginally delays small intestinal transit. Its roles in altering gastrointestinal motility need further investigation.

Treatment of irritable bowel syndrome

WHAT IS KNOWN AND OBJECTIVE

The complexity and diversity of irritable bowel syndrome's (IBS) presentation make treatment difficult. Although there are reviews and guidelines for treating IBS, they focus on the efficacy of medications for IBS symptoms using high-priority endpoints, leaving those of lower priority largely unreported. Therefore, the aim of this review is to provide a comprehensive evidence-based review of the efficacy of medications to treat IBS symptoms, reported by IBS subtype, including secondary symptom endpoints that are often underreported.

METHODS

A review of PubMed for articles published through December 2009 using the keywords: 'irritable bowel syndrome', 'therapeutics', 'antidiarrhoeals', 'laxatives', 'loperamide', 'dietary fibre', 'psyllium', 'calcium polycarbophil', 'bulking agents', 'lubiprostone', 'antidepressant agents, tricyclics' and its representative entities, 'serotonin reuptake inhibitors' and its representative entities, 'dicyclomine', hyoscyamine', 'peppermint oil', 'parasympatholytics' and its representative entities, 'rifaximin', 'pregabalin', 'gabapentin', 'clonidine', 'octreotide', 'atropine' and 'probiotics' is provided. Placebo-controlled trials were evaluated for the strength of evidence supporting the efficacy of each medication for explicit IBS symptoms. The efficacy of each medication for the symptoms of abdominal pain, bloating, stool form, mucus, urgency, feeling of incomplete evacuation, flatulence, frequency, or borborgymi and overall symptoms are reported by IBS subtype.

RESULTS AND DISCUSSION

The literature search identified 58 placebo-controlled trials of the efficacy of medications for treating IBS symptoms, which were critically evaluated and reported. The available studies suggest improvement in various IBS symptoms with loperamide, fibre supplements, lubiprostone, tricyclic antidepressants (TCAs), selective serotonin receptor inhibitors (SSRIs), antispasmotics, rifaximin, pregabalin, gabapentin, clonidine, octreotide and probiotic treatments.

WHAT IS NEW AND CONCLUSION

This review is the first to compile the available evidence on the efficacy of the various pharmacological treatments for IBS on the basis of IBS subtype and specific symptoms. This evidence is limited and more well-designed studies are required to better inform therapeutic decision-making in the management of this difficult syndrome.

Impact of functional gastrointestinal disorders on survival in the community

OBJECTIVES

Functional gastrointestinal disorders (FGIDs) comprise a constellation of symptoms that have no identifiable structural or biochemical abnormality. In view of the lack of data from large-scale population-based studies evaluating the effects of these disorders on survival, we aimed to examine whether FGIDs are associated with impaired survival.

METHODS

Between 1988 and 1993, valid self-report questionnaires that recorded gastrointestinal symptoms required for the diagnosis of irritable bowel syndrome (IBS), chronic constipation, chronic diarrhea, dyspepsia, and abdominal pain were mailed to randomly selected cohorts of Olmsted County, Minnesota residents. Minnesota administrative death records were used to identify which of the survey respondents had died over the follow-up period (through April 2008). The association between survival and each FGID was assessed using proportional hazards regression models with univariate and adjusted hazard ratios (HRs, 95% confidence intervals (CIs)), adjusting for age at time of survey, gender, smoking, alcohol, marital status, and Charlson Comorbidity Index (CCI).

RESULTS

Of the 5,262 randomly selected eligible subjects who received a questionnaire, a total of 4,176 responded to the surveys (overall response rate 79%). From these respondents, 243 subjects were excluded because of lack of research authorization (or were registered solely at a different medical institution in Olmsted County, MN), resulting in 3,933 eligible subjects for analysis (eligible response rate 75%); 10% reported symptoms of IBS; 16% chronic constipation; 18% chronic diarrhea; 2% dyspepsia; and 15% abdominal pain. At baseline, the mean (s.d.) age was 54 (18) years, and 52% were female. No association with overall survival was detected for IBS (HR=1.06 (95% CI: 0.86-1.32)), chronic diarrhea (HR=1.03 (95% CI: 0.90-1.19)), abdominal pain (HR=1.09 (95% CI: 0.92-1.30)), or dyspepsia (HR=1.08 (95% CI: 0.58-2.02)). Reporting symptoms of chronic constipation was associated with poorer survival (HR=1.23 (95% CI: 1.07-1.42)). This association remained significant after adjusting for the CCI (HR=1.19 (95% CI: 1.03-1.37)).

CONCLUSIONS

In this large population-based cohort study with over 30,000 person-years of follow-up, no significant association was observed between survival and IBS, chronic diarrhea, dyspepsia, or abdominal pain. Furthermore, no association was found between increasing burden of FGIDs and survival. However, in contrast to these other FGIDs, subjects with symptoms of chronic constipation were found to be at increased risk of poorer survival. Further investigation is required to determine the cause of this observed association.

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.

Overlapping gastroesophageal reflux disease and irritable bowel syndrome: Increased dysfunctional symptoms

AIM: To investigate the association of gastroesophageal reflux disease (GERD) and irritable bowel syndrome (IBS) in Iranian patients and examine the prevalence of functional symptoms of the gastrointestinal tract in patients presenting with either IBS, GERD or both.

METHODS: Six thousand four hundred and seventy six patients presented to the Gastro-intestinal (GI) clinic with symptoms of functional dysfunction of GI tract, 1419 patients (62.0% women, 38.0% men; mean age: 37.4 ± 11.5 years) met Rome II or Rome III criteria (depending on the year of diagnosis) for IBS. 2658 patients were diagnosed with GERD based on clinical presentation and endoscopic findings. We assessed other functional symptoms (epigastric pain, nausea, vomiting, belching, constipation and diarrhea) in patients suffering from GERD, IBS or both.

RESULTS: Among IBS subjects, 63.6% (69.0% women, 31.0% men; mean age: 36.4 ± 10.3 years) also had GERD, whereas 34.7% of the non-IBS patients had GERD [odds ratio (OR) = 3.2, 95% confidence interval (CI): 2.9-3.7, P < 0.0001]. Among patients with GERD, 33.9% of subjects met Rome criteria compared to 13.5% of non-GERD patients (OR = 3.6, 95% CI: 3.1-4.3, P < 0.0001). Prevalence of all functional symptoms was higher in overlapping GERD and IBS subjects, when compared with their prevalence in the IBS subjects without GERD or GERD only subjects (P < 0.05).

CONCLUSION: This finding shows that in overlapping GERD and IBS, other functional abnormalities of the GI tract are also highly prevalent, suggesting a common underlying dysfunction.

A randomized controlled trial of a cognitive behavioural therapy-based self-management intervention for irritable bowel syndrome in primary care

BACKGROUND

Recent guidelines for the treatment of irritable bowel syndrome (IBS) emphasize the need for research to facilitate home-based self-management for these patients in primary care. The aim of the current study was to test the efficacy of a manualized cognitive behavioural therapy (CBT)-based self-management programme for IBS in a pilot randomized controlled trial (RCT).

METHOD

Sixty-four primary-care patients meeting Rome criteria for IBS were randomized into either self-management plus treatment as usual (TAU) (n=31) or a TAU control condition (n=33). The self-management condition included a structured 7-week manualized programme that was self-administered in conjunction with a 1-hour face-to-face therapy session and two 1-hour telephone sessions. The primary outcome measures were the Subject's Global Assessment (SGA) of Relief and the Irritable Bowel Syndrome Severity Scoring System (IBS-SSS) assessed at baseline, end of treatment (2 months), and 3 and 6 months post-treatment.

RESULTS

Analysis was by intention-to-treat. Twenty-three (76.7%) of the self-management group rated themselves as experiencing symptom relief across all three time periods compared to seven (21.2%) of the TAU controls [odds ratio (OR) 12.2, 95% confidence interval (CI) 3.72-40.1]. At 8 months, 25 (83%) of the self-management group showed a clinically significant change on the IBS-SSS compared to 16 (49%) of the control group (OR 5.3, 95% CI 1.64-17.26).

CONCLUSIONS

This study provides preliminary evidence that CBT-based self-management in the form of a structured manual and minimal therapist contact is an effective and acceptable form of treatment for primary-care IBS patients.

Systematic review: accuracy of symptom-based criteria for diagnosis of irritable bowel syndrome in primary care

BACKGROUND

Despite the trend towards making a positive diagnosis of irritable bowel syndrome (IBS), many health care providers approach IBS as a diagnosis of exclusion.

AIM

To summarize available evidence on the diagnostic performance of symptom-based IBS criteria in excluding organic diseases, and of individual signs and symptoms in diagnosing IBS and to additionally assess the influence of sources of heterogeneity on diagnostic performance.

METHODS

We searched PubMed and EMBASE and screened references. Studies were selected if the design was a primary diagnostic study; the patients were adults consulting because of non-acute abdominal symptoms; the diagnostic test included an externally validated set of IBS criteria, signs, or symptoms. Data extraction and quality assessment were performed by two reviewers independently. The review adhered to the most recent guidelines as described in the Cochrane Diagnostic Reviewers' Handbook.

RESULTS

A total of 25 primary diagnostic studies were included in the review. The performance of symptom-based criteria in the exclusion of organic disease was highly variable. Patients fulfilling IBS criteria had, however, a lower risk of organic diseases than those not fulfilling the criteria.

CONCLUSIONS

With none of the criteria showing sufficiently homogeneous and favourable results, organic disease cannot be accurately excluded by symptom-based IBS criteria alone. However, the low pre-test probability of organic disease especially among patients who meet symptom-based criteria in primary care argues against exhaustive diagnostic evaluation. We advise validation of the new Rome III criteria in primary care populations.

Risk factors for chronic diarrhoea in the community in the absence of irritable bowel syndrome

In contrast to irritable bowel syndrome (IBS), the prevalence and risk factors for diarrhoea in the absence of IBS in the community are unknown. We aimed to evaluate potential risk factors for chronic diarrhoea (non-IBS). A valid questionnaire that recorded gastrointestinal symptoms required for a diagnosis of chronic diarrhoea, self-reported measures of potential risk factors, and a somatic symptom checklist was mailed to an age- and gender-stratified random sample of Olmsted County, Minnesota residents (30-64 year). Chronic diarrhoea was defined as reporting one or more of the following symptoms more than 25% of the time in the past 3 months: > or =3 bowel movements a day, loose or watery stools, or faecal urgency. Subjects with IBS (Rome III) were excluded. Of 892 eligible subjects, 653 (73%) responded. Among 523 respondents not reporting IBS, chronic diarrhoea was reported by 148 (28%); 90 (61%) had chronic painless diarrhoea. Chronic diarrhoea was significantly associated with self-reported food sensitivity (OR = 2.05 [1.31-3.20]) and stress (OR = 1.99 [1.03-3.85]). Both remained significant in the adjusted variable models that excluded subjects with any abdominal pain. Female gender (OR = 0.67 [0.45-0.98]) and higher education level (OR = 0.60 [0.39-0.92]) had smaller odds for chronic diarrhoea. No association was detected for age, marital status, body mass index, cigarette or alcohol use, coffee, analgesics, emotional support, pets or water source. Chronic diarrhoea in the absence of IBS is common; self-reported food sensitivity, male gender and a lower level of education are risk factors.

A randomized controlled trial of imipramine in patients with irritable bowel syndrome

AIM: To study the efficacy of low-dose imipramine in relieving symptoms associated with the irritable bowel syndrome (IBS).

METHODS: A randomized, double-blind trial of 25 mg imipramine vs matched placebo for 12 wk was performed. Doubling the dose was allowed once at week 2 in case of an unsatisfactory early response. Primary efficacy variables were subjective global symptom relief and quality of life (QoL) using SF-36 at week 12.

RESULTS: One hundred and seven patients were enrolled by advertisement or referral by general practitioners and 56 (31 imipramine: 25 placebo) completed the 16-wk study. Baseline characteristics were comparable. A high overall dropout rate was noted in the imipramine and placebo arms (47.5% vs 47.9%, P > 0.05), a mean of 25.0 and 37.4 d from enrollment, respectively (P < 0.05). At the end of 12 wk, there was a significant difference in global symptom relief with imipramine over placebo (per-protocol: 80.6% vs 48.0%, P = 0.01) and a trend on intent-to-treat (ITT) analysis (42.4% vs 25.0%, P = 0.06). This improvement was evident early and persisted to week 16 (P = 0.024 and 0.053 by per-protocol and ITT analyses, respectively). Mean cumulative and component-specific SF-36 scores improved in the imipramine group only (per-protocol, P < 0.01). Drug-related adverse events leading to patient dropout were more common in the imipramine group (25.4% vs 12.5%, P > 0.05).

CONCLUSION: Imipramine may be effective in the treatment of IBS patients and is associated with improved QoL. Careful patient selection, initiation of a low dose with gradual escalation and monitoring for side effects may result in an improved therapeutic response.