Diagnosis, comorbidities, and management of irritable bowel syndrome in patients in a large health maintenance organization

Comparative characteristics of fatigue in irritable bowel syndrome and inflammatory bowel disease: A systematic review and meta-analysis

OBJECTIVE

Fatigue is a common symptom in both irritable bowel syndrome (IBS) and inflammatory bowel disease (IBD), including Crohn's disease (CD) and ulcerative colitis (UC). This study aimed to distinguish fatigue characteristics in IBS and IBD, two functional and organic disorders.

METHODS

We systematically searched the PubMed and Cochrane Library databases from inception to June 30, 2023, and conducted a meta-analysis to generate precise estimates and 95% confidence intervals. The analyses were stratified by fatigue type, severity, sex, disease phase, and comorbidities, and study quality was assessed using Newcastle-Ottawa Scale (NOS).

RESULTS

Our analysis included 74 data (13 IBS, 31 CD, 30 UC) encompassing 16,689 participants (6484 males, 7402 females, and 2803 unknown). Overall, fatigue prevalence trended higher in IBS (54.5% [95%CI, 44.5-64.6]), followed by CD (49.8% [95%CI, 44.0-55.5]) and UC (43.6% [95%CI, 38.5-48.7]). This pattern persisted across sub-analyses, including general fatigue (63.4% vs. 51.3% vs. 45.3%) and moderate to severe fatigue (73.8% vs. 59.5% vs. 52.7%) for IBS, CD, and UC, respectively. Female predominance was observed in all three diseases (odds ratio: 1.5 in IBS and CD, 1.8 in UC). Fatigue prevalence significantly varied between disease phases (active vs. remission) in CD (61.3% vs. 36.3%) and UC (53.8% vs. 32.6%). Anemia, anxiety/depression, and/or IBS-like symptoms also contributed to fatigue in CD and UC.

CONCLUSIONS

This study is the first extensive comparison of fatigue prevalence and features in IBS, CD, and UC. The findings offer valuable insights for treatment and management, aiding our understanding of functional and organic diseases.

Functional Gastrointestinal Disorders

Functional gastrointestinal disorders (FGIDs) are an extremely common set of more than 50 disorders characterized by persistent and recurring gastrointestinal symptoms. Most of these patients can be diagnosed and managed by primary care physicians. Treatment includes patient education and reassurance, eliminating triggers, dietary modification, and pharmacologic management. Primary care physicians should consider referral to gastroenterologists when patients exhibit red flag symptoms such as blood in stool, abnormal laboratory findings, involuntary weight loss, age of presentation greater than 50 years, or certain concerning family history.

Systematic review and meta-analysis of calculating degree of comorbidity of irritable bowel syndrome with migraine

BACKGROUND

Irritable bowel syndrome (IBS) and migraines are often comorbid each other. These disorders are likely to be bidirectionally linked through the gut-brain axis and share several underlying mechanisms including central nervous system sensitization. However, quantitative analysis of comorbidity was not reported enough. The aim of this systematic review and meta-analysis was to calculate the present degree of comorbidity of these two disorders.

METHODS

A literature search was performed searching for articles describing IBS or migraine patients with the same inverse comorbidity. Pooled odds ratios (ORs) or hazard ratios (HRs) with 95% confidence intervals (CIs) were then extracted. The total effect estimates were determined and presented by random effect forest plots for the group of articles with IBS patients with migraine and the group of articles on migraine sufferers with comorbid IBS separately. The average results of these plots were compared.

RESULTS

The literature search resulted in initial 358 articles and final 22 articles for the meta-analysis. The total OR values obtained were 2.09 [1.79 - 2.43] in IBS with comorbid migraine or headache, 2.51 [1.76 - 3.58] for migraineurs with comorbid IBS and an overall HR of 1 .62 [1.29 - 2.03] was found for cohort studies of migraine sufferers with comorbid IBS. A similar expression of a selection of other comorbidities was found in IBS and migraine patients, especially for depression and fibromyalgia a strong similarity was found in their expression rate.

CONCLUSIONS

This systematic review with meta-analysis was the first to combine data on IBS patients with comorbid migraine and migraineurs with comorbid IBS. The fact that closely related existential rates were observed between these two groups should be used as motivation for future research to further investigate these disorders for why this similarity occurs. Mechanisms involved in central hypersensitivity such as genetic risk factors, mitochondrial dysfunction and microbiota are particularly good candidates. Experimental designs in which therapeutic methods for these conditions can be exchanged or combined may also lead to the discovery of more efficient treatment methods.

Tenapanor in the Treatment of Irritable Bowel Syndrome with Constipation: Discovery, Efficacy, and Role in Management

Irritable bowel syndrome (IBS) is a common disorder of gut-brain interaction (DGBI). IBS significantly impacts the quality of life of patients. Since its pathogenesis is unclear and can be multifactorial, it highlights the need for new and improved pharmaceutical drugs that not only improve bowel symptoms, but also address global IBS symptoms, such as abdominal pain. Tenapanor, a recently Food & Drug Administration (FDA)-approved medication for IBS with constipation (IBS-C), is a small molecule inhibitor of the sodium/hydrogen exchanger isoform 3 (NHE₃) that inhibits the absorption of sodium and phosphate in the gastrointestinal tract, resulting in fluid retention and softer stool. Furthermore, tenapanor reduces intestinal permeability to improve visceral hypersensitivity and abdominal pain. Due to its recent approval, tenapanor was not included in the recent IBS guidelines, however, it may be considered for IBS-C patients failing first-line treatment of soluble fiber. In this review article, we aim to provide in-depth information to the reader regarding the design of tenapanor, its development through Phase I, II and III randomized clinical trials, and its role in the treatment of IBS-C.

Comorbid extra-intestinal central sensitization conditions worsen irritable bowel syndrome in primary care patients

BACKGROUND

Irritable bowel syndrome (IBS) is characterized as a central sensitization syndrome (CSS), a group of conditions including fibromyalgia, chronic fatigue, and restless leg syndrome (RLS) among others with frequent comorbidities of anxiety, depression, and chemical sensitivity. The prevalence of comorbid conditions and their impact on IBS symptom severity and quality of life in rural community populations has not been described.

METHODS

We administered a cross-sectional survey to patients with a documented CSS diagnosis in rural primary care practices to evaluate the relationship between CSS diagnoses, quality of life, symptom severity, and interactions with healthcare providers utilizing validated questionnaires. Subgroup analysis was performed on the IBS cohort. Mayo Clinic IRB approved the study.

KEY RESULTS

Seven hundred seventy-five individuals out of 5000 completed the survey (15.5% response rate) with 264 (34%) reporting IBS. Only 3% (n = 8) of IBS patients reported IBS alone without comorbid CSS condition. Most respondents reported overlapping migraine (196, 74%), depression (183, 69%), anxiety (171, 64%), and fibromyalgia (139, 52%). IBS patients with more than two comorbid CS condition showed significantly higher symptom severity with linear increase. Quality of life was lower in IBS with comorbid conditions, particularly in patients with IBS and RLS (mean EQ5-D 0.36 vs. 0.8 in IBS only, p < 0.01). Quality of life declined as number of comorbid conditions increased.

CONCLUSIONS & INFERENCES

Patients with IBS often have multiple CS disorders which increases symptom severity and lowers quality of life. Understanding the impact of multiple CSS diagnoses and treating these as a global condition may improve patient experience.

Italian guidelines for the management of irritable bowel syndrome: Joint Consensus from the Italian Societies of: Gastroenterology and Endoscopy (SIGE), Neurogastroenterology and Motility (SINGEM), Hospital Gastroenterologists and Endoscopists (AIGO), Digestive Endoscopy (SIED), General Medicine (SIMG), Gastroenterology, Hepatology and Pediatric Nutrition (SIGENP) and Pediatrics (SIP)

The irritable bowel syndrome (IBS) is a chronic disorder of gut-brain interaction. IBS is still associated with areas of uncertainties, especially regarding the optimal diagnostic work-up and the more appropriate management. Experts from 7 Italian Societies conducted a Delphi consensus with literature summary and voting process on 27 statements. Recommendations and quality of evidence were evaluated using the grading of recommendations, assessment, development, and evaluation (GRADE) criteria. Consensus was defined as >80% agreement and reached for all statements. In terms of diagnosis, the consensus supports a positive diagnostic strategy with a symptom-based approach, including the psychological comorbidities assessment and the exclusion of alarm symptoms, together with the digital rectal examination, full blood count, C-reactive protein, serology for coeliac disease, and fecal calprotectin assessment. Colonoscopy should be recommended in patients with alarm features. Regarding treatment, the consensus strongly supports a dietary approach for patients with IBS, the use of soluble fiber, secretagogues, tricyclic antidepressants, psychologically directed therapies and, only in specific IBS subtypes, rifaximin. A conditional recommendation was achieved for probiotics, polyethylene glycol, antispasmodics, selective serotonin reuptake inhibitors and, only in specific IBS subtypes, 5-HT3 antagonists, 5-HT4 agonists, bile acid sequestrants.

Identification of putative transcriptomic biomarkers in irritable bowel syndrome (IBS): Differential gene expression and regulation of TPH1 and SERT by vitamin D

Irritable bowel syndrome (IBS) is one of the most common gastrointestinal disorders and affects approximately 4% of the global population. The diagnosis of IBS can be made based on symptoms using the validated Rome criteria and ruling out commonly occurring organic diseases. Although biomarkers exist for "IBS mimickers" such as celiac disease and inflammatory bowel disease (IBD), no such test exists for IBS. DNA microarrays of colonic tissue have been used to identify disease-associated variants in other gastrointestinal (GI) disorders. In this study, our objective was to identify biomarkers and unique gene expression patterns that may define the pathological state of IBS. Mucosal tissue samples were collected from the sigmoid colon of 29 participants (11 IBS and 18 healthy controls). DNA microarray analysis was used to assess gene expression profiling. Extraction and purification of RNA were then performed and used to synthesize cDNA. Reverse transcriptase quantitative polymerase chain reaction (RT-qPCR) was employed to identify differentially expressed genes in patients diagnosed with IBS compared to healthy, non-IBS patient-derived cDNA. Additional testing probed vitamin D-mediated regulation of select genes associated with serotonergic metabolism. DNA microarray analyses led to the identification of 858 differentially expressed genes that may characterize the IBS pathological state. After screening a series of genes using a combination of gene ontological analysis and RT-qPCR, this spectrum of potential IBS biomarkers was narrowed to 23 genes, some of which are regulated by vitamin D. Seven putative IBS biomarkers, including genes involved in serotonin metabolism, were identified. This work further supports the hypothesis that IBS pathophysiology is evident within the human transcriptome and that vitamin D modulates differential expression of genes in IBS patients. This suggests that IBS pathophysiology may also involve vitamin D deficiency and/or an irregularity in serotonin metabolism.

Biomolecules from Plant Wastes Potentially Relevant in the Management of Irritable Bowel Syndrome and Co-Occurring Symptomatology

During and following the processing of a plant’s raw material, considerable amounts are wasted, composted, or redistributed in non-alimentary sectors for further use (for example, some forms of plant waste contribute to biofuel, bioethanol, or biomass production). However, many of these forms of waste still consist of critical bioactive compounds used in the food industry or medicine. Irritable bowel syndrome (IBS) is one of the most common functional gastrointestinal disorders. The primary treatment is based on symptomatology alleviation and controlled dietary management. Thus, this review aimed to describe the possible relevance of molecules residing in plant waste that can be used to manage IBS and co-occurring symptoms. Significant evidence was found that many forms of fruit, vegetable, and medicinal plant waste could be the source of some molecules that could be used to treat or prevent stool consistency and frequency impairments and abdominal pain, these being the main IBS symptoms. While many of these molecules could be recovered from plant waste during or following primary processing, the studies suggested that enriched food could offer efficient valorization and prevent further changes in properties or stability. In this way, root, stem, straw, leaf, fruit, and vegetable pomaces were found to consist of biomolecules that could modulate intestinal permeability, pain perception, and overall gastrointestinal digestive processes.

The Ketogenic Diet Improves Gut-Brain Axis in a Rat Model of Irritable Bowel Syndrome: Impact on 5-HT and BDNF Systems

Altered gut-brain communication can contribute to intestinal dysfunctions in the intestinal bowel syndrome. The neuroprotective high-fat, adequate-protein, low-carbohydrate ketogenic diet (KD) modulates the levels of different neurotransmitters and neurotrophins. The aim was to evaluate the effects of KD on levels of 5-HT, the receptors 5-HT_3B and 5-HT₄, the 5-HT transporter SERT, the neurotrophin BDNF, and its receptor TrkB in the colon and brain of a rat model of irritable bowel syndrome (IBS). Samples from Wistar rats exposed to maternal deprivation as newborns and then fed with a standard diet (IBS-Std) or KD (IBS-KD) for ten weeks were analyzed. As controls, unexposed rats (Ctrl-Std and Ctrl-KD) were studied. IBS-Std rats had a disordered enteric serotoninergic signaling shown by increased mucosal 5-HT content and reduced SERT, 5-HT_3B, and 5-HT₄ levels compared to controls. In the brain, these animals showed up-regulation of the BDNF receptor TrkB as a counteracting response to the stress-induced reduction of the neurotrophin. KD showed a dual effect in improving the altered 5-HT and BDNF systems. It down-regulated the increased mucosal 5-HT without affecting transporter and receptor levels. KD improved brain BDNF levels and established negative feedback, leading to a compensatory downregulation of TrkB to maintain a physiological steady state.

A survey of gastroenterologists in the United States on the use of central neuromodulators for treating irritable bowel syndrome

BACKGROUND

Central neuromodulators are an effective treatment for irritable bowel syndrome (IBS) but may be used less frequently than other therapies.

AIMS

To survey gastroenterologists in the United States (US) about their use of neuromodulators in patients with IBS.

METHODS

A 23-question survey was distributed to gastroenterologists in the United States. Comparisons in prescribing practices were conducted between (a) gastroenterologists who were "high prescribers" versus "low prescribers" of neuromodulators in patients with IBS and (b) gastroenterologists and "gastroenterology experts" in the use of neuromodulators using descriptive statistics and multivariable logistic regression analyses.

RESULTS

The 525 gastroenterologists who were surveyed used neuromodulators for a median range of 21%-30% of their patients with IBS. Neuromodulators were described as extremely/very important in managing IBS by 55% of clinicians. Significant predictors of high-prescribing behaviour were academic versus clinical practice setting (odds ratio [OR] 2.60 [95% CI 1.61-4.20]), disorders of brain-gut interaction focused practice (OR 4.80 [2.60-8.84]), and greater perceived effectiveness of neuromodulators (OR 2.75 [1.30-5.84]). Compared to gastroenterologists, experts prescribed neuromodulators to a higher percentage of their patients with IBS (41%-50% vs 21%-30%; P = 0.019) and more frequently found neuromodulators effective (70% vs 27%; P = 0.003). However, concern about side effects was the most common barrier to neuromodulator use (59%).

CONCLUSIONS

The majority of US gastroenterologists believe central neuromodulators are important in treating IBS, and 27% believe they are effective in most patients. High prescribers are in academic practice, focus in IBS and perceive central neuromodulators as effective. Education is needed to improve gastroenterologists' prescribing behaviour.

Lactobacillus plantarum PS128 Ameliorated Visceral Hypersensitivity in Rats Through the Gut-Brain Axis

Irritable bowel syndrome (IBS) is a common functional gastrointestinal disorder characterized by abdominal pain and alterations in bowel habits. Current treatments for IBS are unsatisfactory due to its multifactorial pathogenesis involving the microbiota-gut-brain axis. Lactobacillus plantarum PS128 (PS128) was reported to exhibit neuromodulatory activity which may be beneficial for improving IBS. This study aimed to investigate the effect of PS128 on visceral hypersensitivity (VH) and the gut-brain axis using a 5-hydroxytryptophan (5-HTP)-induced VH rat model without colonic inflammation induction, mimicking the characteristics of IBS. Male Sprague-Dawley rats were administered with PS128 (10⁹ CFU in 0.2 mL saline/rat/day) or saline (0.2 mL saline/rat/day) for 14 days. Colorectal distension (CRD) with simultaneous electromyography recording was performed 30 min before and 30 min after the 5-HTP injection. Levels of neuropeptides and neurotrophins were analyzed. PS128 significantly reduced VH induced by the 5-HTP injection and CRD. Neurotransmitter protein levels, substance P, CGRP, BDNF, and NGF, were decreased in the dorsal root ganglion but increased in the spinal cord in response to the 5-HTP injection; PS128 reversed these changes. The hypothalamic-pituitary-adrenal axis was modulated by PS128 with decreased corticosterone concentration in serum and the expression of mineralocorticoid receptors in the amygdala. Oral administration of PS128 inhibited 5-HTP-induced VH during CRD. The ameliorative effect on VH suggests the potential application of PS128 for IBS.

ACG Clinical Guideline: Management of Irritable Bowel Syndrome

Irritable bowel syndrome (IBS) is a highly prevalent, chronic disorder that significantly reduces patients' quality of life. Advances in diagnostic testing and in therapeutic options for patients with IBS led to the development of this first-ever American College of Gastroenterology clinical guideline for the management of IBS using Grading of Recommendations, Assessment, Development, and Evaluation (GRADE) methodology. Twenty-five clinically important questions were assessed after a comprehensive literature search; 9 questions focused on diagnostic testing; 16 questions focused on therapeutic options. Consensus was obtained using a modified Delphi approach, and based on GRADE methodology, we endorse the following: We suggest that a positive diagnostic strategy as compared to a diagnostic strategy of exclusion be used to improve time to initiating appropriate therapy. We suggest that serologic testing be performed to rule out celiac disease in patients with IBS and diarrhea symptoms. We suggest that fecal calprotectin be checked in patients with suspected IBS and diarrhea symptoms to rule out inflammatory bowel disease. We recommend a limited trial of a low fermentable oligosaccharides, disacchardies, monosaccharides, polyols (FODMAP) diet in patients with IBS to improve global symptoms. We recommend the use of chloride channel activators and guanylate cyclase activators to treat global IBS with constipation symptoms. We recommend the use of rifaximin to treat global IBS with diarrhea symptoms. We suggest that gut-directed psychotherapy be used to treat global IBS symptoms. Additional statements and information regarding diagnostic strategies, specific drugs, doses, and duration of therapy can be found in the guideline.

Antidepressants in inflammatory bowel disease

Gut-brain dysregulation has been recognized by the scientific community as being crucial to the understanding of chronic gastrointestinal conditions, and this has translated into the practice of a newly established discipline, psychogastroenterology. Along with psychotherapy, antidepressants (a subtype of central neuromodulators) have been proposed as treatments for gut-brain disorders that might benefit both psychological and gastrointestinal health. Antidepressants have been found to be effective for the treatment of comorbid anxiety and depression, pain and impaired sleep. Although the efficacy of antidepressants is well established in disorders of gut-brain interaction (DGBI), evidence is only now emerging in IBD. This Perspective discusses the use of antidepressants in DGBI and IBD, focusing on how what we have learnt about the role of antidepressants in DGBI could be applied to help optimize the management of IBD.

Relationships of Microbiome Markers With Extraintestinal, Psychological Distress and Gastrointestinal Symptoms, and Quality of Life in Women With Irritable Bowel Syndrome

INTRODUCTION

Altered microbial diversity has been associated with gastrointestinal (GI) symptoms in persons with irritable bowel syndrome (IBS). Less is known about the relationship of microbiome with extraintestinal pain and psychological distress symptoms and quality of life (QOL) in persons with IBS. We aimed to evaluate the relationship of fecal microbiota to GI symptoms, stool consistency, psychological distress, extraintestinal pain, and QOL in participants meeting Rome III criteria for IBS.

METHODS

Seventy-six women completed a 28-day diary that included GI, stool consistency, psychological distress, and extraintestinal pain ratings. Participants completed the IBS-Specific Quality of Life questionnaire. Stool samples were collected and analyzed by 16S rRNA gene sequencing. Principal component analysis was performed and the first 2 components (PC1, PC2) were used to test relationships among bacterial families and clinical measures.

RESULTS

Participants were categorized as IBS constipation (n=22), IBS diarrhea (n=39), IBS mixed (n=13), and IBS unsubtyped (n=2). There was a significant group effect for the Firmicutes to Bacteroidetes ratio and PC1. Lower microbial diversity and richness were associated with increased urgency and extraintestinal pain, worse QOL, and looser stools. Lower extraintestinal pain was associated with increased Rikenellaceae, Christensenellaceae, Dehalobabacteriaceae, Oscillospiraceae, Mogibacteriaceae, Ruminococcaceae, Sutterellaceae, Desulfovibrionaceae, and Erysipelotrichaceae abundances. QOL was positively associated with many of these same bacterial families. Higher Firmicutes to Bacteroidetes ratio was positively associated with loose stools. There were no statistically significant relationships between daily psychological distress or abdominal pain and bacterial families.

CONCLUSIONS

Stool microbial diversity and composition are linked to daily extraintestinal symptoms, stool consistency, and QOL in women with IBS.

Nonpharmacologic options for treating irritable bowel syndrome

Irritable bowel syndrome (IBS) is a chronic functional disorder with no organic cause. Risk factors are multifactorial and treatment typically consists of antimotility or stimulant laxatives and antidepressants. This article reviews several newer areas of interest: probiotics, fecal microbiota transplant, a low FODMAP diet, and cognitive behavioral therapy.

Systematic review with meta-analysis: the prevalence of anxiety and depression in patients with irritable bowel syndrome

BACKGROUND

Irritable bowel syndrome (IBS) is a common and potential disabling functional gastrointestinal disorder. Studies have revealed a possible association between IBS and psychological problems, such as anxiety and depression. Existing systematic reviews have addressed only the levels of anxiety or depression in patients with IBS.

AIM

To investigate systematically the prevalence of anxiety or depression in IBS patients METHODS: A literature search was conducted using the related keywords from the bibliographic databases of Embase, PubMed, Scopus, Web of Science and POPLINE published until 1 January 2019 with no language restriction. Studies reporting the prevalence of anxiety/depressive symptoms/disorders in adult (≥15 years) IBS patients were evaluated. The pooled prevalence, odds ratio (OR) and 95% CI were calculated using stata software.

RESULTS

A total of 14 926 articles were initially screened, and finally 73 papers were included. The prevalence rates of anxiety symptoms and disorders in IBS patients were 39.1% (95% CI: 32.4-45.8) and 23% (95% CI: 17.2-28.8) respectively. The ORs for anxiety symptoms and disorders in IBS patients compared with healthy subjects were 3.11 (95% CI: 2.43-3.98) and 2.52 (95% CI: 1.99-3.20) respectively. The prevalence estimates of depressive symptoms and disorders in IBS patients were 28.8% (95% CI: 23.6-34) and 23.3% (95% CI: 17.2-29.4) respectively. The ORs for depressive symptoms and disorders in IBS patients compared to healthy subjects were 3.04 (95% CI: 2.37-3.91) and 2.72 (95% CI: 2.45-3.02) respectively.

CONCLUSION

Patients with IBS have a three-fold increased odds of either anxiety or depression, compared to healthy subjects.

IBS clinical management in Italy: The AIGO survey

BACKGROUND

Irritable bowel syndrome (IBS) is the most frequent functional gastrointestinal disorder, both in primary and secondary care.

AIMS

(1) To describe diagnostic tools and treatments suggested to IBS patients by Italian gastroenterologists; (2) To evaluate patients' quality of life and psychological involvement and the relationship of these factors with symptom severity.

METHODS

Twenty-six gastroenterologists recorded the demographic and clinical data of 677 IBS patients. Diagnostic and treatment measures taken in the previous year and those suggested by gastroenterologists were analysed.

RESULTS

IBS with constipation was found in 43.4%, with diarrhoea in 21.6%, mixed-IBS in 35.0%. Routine blood tests, ultrasonography, colonoscopy, barium enema and CT were more frequently requested in the previous year than by the gastroenterologists (p < 0.001). Colonoscopy (11%), and ultrasonography (20.4%) were also suggested by the gastroenterologists in a non-negligible number of patients. Abdominal pain and distension, bowel dissatisfaction, anxiety and depression were more severe in females than in males. Quality of life decreased with increasing IBS-symptom severity.

CONCLUSIONS

IBS diagnosis is still largely based on exclusion criteria even if gastroenterologists try to improve diagnostic appropriateness. However, therapy remains symptom-based also in the gastroenterological setting even if gastroenterologists use a wide variety of approaches, including innovative therapies such as linaclotide and psychotherapy.

Gut microbiota and bipolar disorder: a review of mechanisms and potential targets for adjunctive therapy

There is increasing evidence that connections formed between microbiome, the gut, and the brain play a role in health and well-being. Non-pharmaceutical targets for management of mood disorders, such as bipolar disorder, are relatively under-researched. At the same time, it is clear that there is an intimate connection between psychiatry and gastrointestinal health. Here, we have discussed various comorbid conditions associated with bipolar disorders such as inflammation, irritable bowel disease and antibiotic induced mania with importance to demonstrate possible involvement of the gut microbiota. Gut microbiota-targeted preclinical and clinical interventions have demonstrated enhancement in various psychological conditions. Further in this review, we explore links between bipolar disorder, inflammation and gut microbiome with a focus on dietary, pro- and pre-biotic interventions as potential adjuvant therapies for use in the management of mood disorders such as bipolar disorder.

Low fermentable oligosaccharides, disaccharides, monosaccharides, and polypols diet and irritable bowel syndrome in Asia

Functional bowel disorders, including irritable bowel syndrome (IBS), are a chronic condition that can significantly reduce patients' quality of life. Therefore, this paper will review the roles of a low fermentable oligosaccharides, disaccharides, monosaccharides, and polypols (FODMAP) diet in treating IBS, particularly in an Asian setting. About 20% of the general population is diagnosed with IBS. However, there are limited effective medical therapies available for treating IBS. Therefore, IBS presents a major challenge to the health-care providers. Recently, there is an increasing interest in the use of a diet low in FODMAP for the treatment of IBS. A low FODMAP diet can decrease the delivery of readily fermentable substrates to the small intestine and colon, thereby improving functional gastrointestinal symptoms.

A Patient-Centered Proposal for Bayesian Analysis of Self-Experiments for Health

The rise of affordable sensors and apps has enabled people to monitor various health indicators via self-tracking. This trend encourages self-experimentation, a subset of self-tracking in which a person systematically explores potential causal relationships to try to answer questions about their health. Although recent research has investigated how to support the data collection necessary for self-experiments, less research has considered the best way to analyze data resulting from these self-experiments. Most tools default to using traditional frequentist methods. However, the US Agency for Healthcare Research and Quality recommends using Bayesian analysis for n-of-1 studies, arguing from a statistical perspective. To develop a complementary patient-centered perspective on the potential benefits of Bayesian analysis, this paper describes types of questions people want to answer via self-experimentation, as informed by 1) our experiences engaging with irritable bowel syndrome patients and their healthcare providers and 2) a survey investigating what questions individuals want to answer about their health and wellness. We provide examples of how those questions might be answered using 1) frequentist null hypothesis significance testing, 2) frequentist estimation, and 3) Bayesian estimation and prediction. We then provide design recommendations for analyses and visualizations that could help people answer and interpret such questions. We find the majority of the questions people want to answer with self-tracking data are better answered with Bayesian methods than with frequentist methods. Our results therefore provide patient-centered support for the use of Bayesian analysis for n-of-1 studies.

Effect of Antidepressants and Psychological Therapies in Irritable Bowel Syndrome: An Updated Systematic Review and Meta-Analysis

OBJECTIVES

Irritable bowel syndrome (IBS) is a chronic functional bowel disorder that is thought to be due to a disorder of brain-gut function. Drugs acting centrally, such as antidepressants, and psychological therapies may, therefore, be effective.

METHODS

We updated a previous systematic review and meta-analysis of randomized controlled trials (RCTs). MEDLINE, EMBASE, PsychINFO, and the Cochrane Controlled Trials Register were searched (up to July 2017). Trials recruiting adults with IBS, which compared antidepressants versus placebo, or psychological therapies versus control therapy or "usual management" were eligible. Dichotomous symptom data were pooled to obtain a relative risk (RR) of remaining symptomatic after therapy, with a 95% confidence interval (CI).

RESULTS

The search strategy identified 5316 citations. Fifty-three RCTs, reported in 51 separate articles, were eligible for inclusion: 17 compared antidepressants with placebo, 35 compared psychological therapies with control therapy or "usual management", and one compared both psychological therapy and antidepressants with placebo. Four of the trials of psychological therapies, and one of the RCTs of antidepressants, were identified since our previous meta-analysis. The RR of IBS symptoms not improving with antidepressants versus placebo was 0.66 (95% CI 0.57-0.76), with similar treatment effects for both tricyclic antidepressants and SSRIs, although with heterogeneity between RCTs of the latter (I(2) = 49%, P = 0.07). The RR of symptoms not improving with psychological therapies was 0.69 (95% CI 0.62-0.76). Cognitive behavioral therapy, relaxation therapy, multi-component psychological therapy, hypnotherapy, and dynamic psychotherapy were all beneficial when data from two or more RCTs were pooled. There was significant heterogeneity between studies (I(2) = 69%, P < 0.001) and significant funnel plot asymmetry. There were also issues regarding trial design, including lack of blinding.

CONCLUSIONS

Antidepressants are efficacious in reducing symptoms in IBS patients. Psychological therapies also appear to be effective treatments for IBS, although there are limitations in the quality of the evidence, and treatment effects may be overestimated as a result.

Factors associated with more frequent diagnostic tests and procedures in patients with irritable bowel syndrome

BACKGROUND

Irritable bowel syndrome (IBS) reduces quality of life and burdens healthcare systems. This study identified factors associated with frequent use of IBS diagnostic tests and procedures.

METHODS

Using a United States claims database (2001-2012), tests and procedures in IBS patients occurring in the 2-year study period (12 months before/following the first IBS diagnosis) were analyzed: endoscopy, GI transit testing, anorectal procedures, and radiologic imaging. Patients were classified based on test/procedure frequency (3+, 1-2, or 0). Multivariate logistic regression identified factors associated with more frequent tests/procedures.

RESULTS

Among 201,322 IBS patients, 41.7% had 3+ tests/procedures, 35.1% had 1-2, and 23.3% had 0. Patients with more tests/procedures were older [mean age 50.6 (3+ group), more likely to be female and had more comorbidities, including anxiety, depressive disorders, and somatization. Dyspepsia [odds ratio (95% confidence interval): 1.80 (1.72-1.87)], interstitial cystitis [1.60 (1.45-1.77)], gastroesophageal reflux disease [1.59 (1.55-1.63)], constipation [1.50 (1.45-1.54)], and dyspareunia [1.38 (1.25-1.52)] were significantly associated with more tests/procedures (3+ versus 1-2), while anxiety, depressive disorders, and somatization were not. Patients with more frequent specialist visits [emergency department (ED; 1.10 (1.09-1.11)) and gastroenterologists (1.26 (1.26-1.27))] or at least one GI-related ED visit or inpatient admission [1.95 (1.86-2.04) and 3.67 (3.48-3.87), respectively] were more likely to have more tests/procedures (all p < 0.05).

CONCLUSIONS

Test frequency in patients with IBS is strongly associated with demographic and clinical characteristics, especially comorbid conditions related to IBS. Presence of common overlapping comorbid conditions should increase clinicians' confidence in making the diagnosis of IBS, thus curtailing redundant testing and reducing healthcare costs.

Irritable bowel syndrome in Asia: Pathogenesis, natural history, epidemiology, and management

Historically, the epidemiology of gastrointestinal diseases in Asia was different from that in Western countries. Early studies suggested a low prevalence of irritable bowel syndrome (IBS) in Asia. As the diagnosis of IBS is symptom-based and as symptom perception, expression, and interpretation are influenced by sociocultural perspectives including language, the presentation of IBS is expected to vary in different communities. Furthermore, the pathogenesis is multifactorial with psychosocial (stress, illness, behavior, and diet) and biological (infection, gut microbiota, and immune activation) variables interacting, and so, the present study can anticipate that the development of IBS will vary in different environments. In recognition of this aspect of functional gastrointestinal disorders, the recently published Rome IV documents have provided greater focus on cross-cultural factors. In this review, the present study seeks to highlight Asian perspectives by identifying historical trends and recent publications from the region and comparing these with the observations from Western societies.

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

Irritable bowel syndrome (IBS) is a complex functional gastrointestinal disorder that is exceedingly common in clinical practice. IBS with predominant constipation (IBS-C) is a subtype of IBS that accounts for more than a third of the IBS diagnosed. Diagnosis of IBS requires a careful personalized approach, a comprehensive clinical history, limited but relevant investigations, and continued follow-up. Major IBS societies and guidelines recommend offering a positive diagnosis of IBS based on presenting symptomatology. Abdominal pain that may or may not be relieved by defecation is the cardinal symptom of IBS; distension and bloating are other common symptoms. Careful attention should be paid to alarm symptoms before a diagnosis of IBS is made. Pharmacotherapy with linaclotide is recommended for moderate-severe IBS-C, based on high-quality evidence from randomized controlled trials. Diarrhea is the major side effect of linaclotide, and limited cost-effectiveness data currently exist.

Ameliorative effect of chlorpromazine hydrochloride on visceral hypersensitivity in rats: possible involvement of 5-HT2A receptor

BACKGROUND AND PURPOSE

Visceral hypersensitivity is responsible for pathogenesis of irritable bowel syndrome (IBS). Therefore, its prevention can help avoid abdominal pain and discomfort in IBS. To find candidate drugs for visceral hypersensitivity, we screened existing medicines for their ability to prevent visceral sensitivity induced by colorectal distension (CRD) in rats and identified chlorpromazine, a typical antipsychotic drug, as a candidate compound. In this study, we investigated the effect of chlorpromazine on visceral hypersensitivity.

EXPERIMENTAL APPROACH

Visceral sensitivity (visceromotor response) was monitored by measuring the electrical activity of the abdominal external oblique muscle contraction in response to CRD using a barostat apparatus. Visceral hypersensitivity was induced by a colonic instillation of sodium butyrate or acetic acid in neonates.

KEY RESULTS

Oral administration of chlorpromazine suppressed butyrate-induced visceral hypersensitivity to CRD. Interestingly, atypical antipsychotic drugs, quetiapine and risperidone, ameliorated butyrate-induced visceral hypersensitivity, whereas the typical antipsychotic drugs, haloperidol and sulpiride, did not. Pharmacological analysis using specific inhibitors showed that a selective 5-HT_2A receptor antagonist, ketanserin, suppressed butyrate-induced visceral hypersensitivity, whereas a selective dopamine D₂ receptor antagonist, L-741626, did not. Furthermore, the 5-HT_2A receptor agonist AL-34662 stimulated visceral sensitivity to CRD in healthy control rats but not in butyrate-treated rats. These findings suggest that increased 5-HT levels in the colon contribute to the induction of visceral hypersensitivity.

CONCLUSIONS AND IMPLICATIONS

Our results indicate that chlorpromazine ameliorates visceral hypersensitivity and that the 5-HT_2A receptor is a potential therapeutic target for treating abdominal pain and discomfort in IBS.

Rome foundation Asian working team report: Real world treatment experience of Asian patients with functional bowel disorders

BACKGROUND AND AIM

Information on real world treatment experiences of patients with functional bowel disorders is lacking from Asia. This study aimed to describe the medication exposure and treatment satisfaction of patients presenting to gastroenterology clinics across a sampling of Asian cities.

METHODS

From March 2011 to October 2013, adult patients presenting to hospital-based gastroenterology outpatient clinics in 11 cities across Asia, who fulfilled screening criteria for any functional gastrointestinal disorder, were asked to complete a validated culturally adapted translation of the Rome III diagnostic questionnaire, a checklist of medications received in the preceding 3 months and questions on treatment satisfaction.

RESULTS

A total of 1376 patients (female 755, male 621, 41.36 ± 13.25 years) comprising irritable bowel (621, 45.1%), unspecified functional bowel disorder (372, 27.8%), functional constipation (202, 14.7%), functional bloating (144, 10.5%), and functional diarrhea (56, 4.1%) completed the study. Of 1105 patients with a previous consultation, 509 (46.1%) were dissatisfied with their treatment, with ineffective treatment being the commonest reason. Satisfaction with previous consultation was lowest by diagnosis for functional constipation (29.2%), and the most bothersome symptom was straining (37.5%). Of 1046 patients who had taken medications for their gastrointestinal symptoms in the last 3 months, 793 (75.8%) had received two or more drugs. For irritable bowel syndrome patients, treatment with proton pump inhibitors and antispasmodics was recorded in 57% and 31%, with overlapping epigastric pain and heartburn predicting proton pump inhibitors use.

CONCLUSIONS

More attention should be given to treatment gaps with regards to possible under-treatment with antispasmodics in irritable bowel syndrome and to critically evaluating the efficacy of constipation management.

Comparison of Symptoms, Healthcare Utilization, and Treatment in Diagnosed and Undiagnosed Individuals With Diarrhea-Predominant Irritable Bowel Syndrome

OBJECTIVES

Irritable bowel syndrome (IBS) is a functional bowel disorder characterized by symptoms including abdominal pain and altered bowel function. Up to 75% of individuals with IBS may be undiagnosed. The aim of this study was to characterize symptoms, healthcare utilization, and treatments in populations with both diagnosed and undiagnosed IBS.

METHODS

An online survey was conducted to compare gastrointestinal (GI) symptoms, healthcare visits, well-being, symptom management, and treatment satisfaction in individuals with and without medically diagnosed IBS (Rome III criteria). Symptom severity, disruptiveness, and treatment satisfaction were rated using a 7-point scale. Adjustments to daily life were determined by predefined survey responses.

RESULTS

A total of 1,924 individuals with a history of GI symptoms were eligible and completed the survey. Of these, 1,094 individuals (56.9%) met the criteria for IBS; 830 individuals (43.1%) had no medical diagnosis of IBS despite meeting diagnostic criteria. Most participants received a diagnosis from either gastroenterologists (45%) or primary care physicians (42%). A greater percentage of diagnosed patients had severe GI symptoms (score ≥6) vs. undiagnosed individuals (16% vs. 8%, respectively; P<0.05); diagnosed patients were more likely to report that GI symptoms adversely affected their quality of life. Approximately 40% of participants received IBS-related treatment from primary care physicians; 26% and 43% of diagnosed and undiagnosed individuals, respectively, were not receiving treatment for GI symptoms.

CONCLUSIONS

Many individuals with IBS-related symptoms have not been medically diagnosed with IBS. IBS-related symptoms impact quality of life, yet more than one-third of individuals are not receiving treatment for IBS.

TummyTrials: A Feasibility Study of Using Self-Experimentation to Detect Individualized Food Triggers

Diagnostic self-tracking, the recording of personal information to diagnose or manage a health condition, is a common practice, especially for people with chronic conditions. Unfortunately, many who attempt diagnostic self-tracking have trouble accomplishing their goals. People often lack knowledge and skills needed to design and conduct scientifically rigorous experiments, and current tools provide little support. To address these shortcomings and explore opportunities for diagnostic self-tracking, we designed, developed, and evaluated a mobile app that applies a self-experimentation framework to support patients suffering from irritable bowel syndrome (IBS) in identifying their personal food triggers. TummyTrials aids a person in designing, executing, and analyzing self-experiments to evaluate whether a specific food triggers their symptoms. We examined the feasibility of this approach in a field study with 15 IBS patients, finding that participants could use the tool to reliably undergo a self-experiment. However, we also discovered an underlying tension between scientific validity and the lived experience of self-experimentation. We discuss challenges of applying clinical research methods in everyday life, motivating a need for the design of self-experimentation systems to balance rigor with the uncertainties of everyday life.

The Severity of Symptoms Related to Irritable Bowel Syndrome is a Risk Factor for the Misclassification of Significant Organic Disease

BACKGROUND AND AIMS

The diagnosis of irritable bowel syndrome (IBS) is based mainly on clinical evaluation. The reported incidence of misclassification of significant organic diseases in previously diagnosed IBS patients differs between studies. The aim of this study was to examine the incidence and risk factors for the misclassification of significant organic disease [colon cancer, inflammatory bowel disease (IBD), Celiac disease, and thyroid dysfunction] in a cohort of young patients with symptoms attributed to IBS.

METHODS

In this population-based cohort study, we examined the incidence and risk factors for the diagnosis of a new significant organic diseases in a cohort of 2645 IBS patients.

RESULTS

During follow-up, organic disease was diagnosed in 27 subjects (1.03%): IBD in 23, Celiac disease in 2, IBD and Celiac disease in 1, and hypothyroidism in1. The mean interval from the diagnosis of IBS to the diagnosis of an organic disorder was 13.08±8.51 months. Increased symptom severity was the only significant risk factor for the misclassification of an organic disease (hazard ratio, 2.26; 95% confidence interval, 1.01-5.05; P=0.047). The risk ratio for misclassification of organic diseases in moderate to severe IBS was increased by 2.575 (95% confidence interval, 1.10-6.51; P=0.027) as compared with mild IBS.

CONCLUSIONS

The incidence of misclassification of major organic disease in IBS patients was low. Increased symptoms severity was the only significant risk factor for the misclassification of organic disorders. Further gastrointestinal evaluation should be considered in patients with moderate to severe symptoms attributed to IBS.

Diarrhea-predominant irritable bowel syndrome: Diagnosis, etiology, and new treatment considerations

PURPOSE

To provide an overview of irritable bowel syndrome (IBS), specifically the efficacy and tolerability of treatment options for diarrhea-predominant IBS (IBS-D).

DATA SOURCES

Research articles available via PubMed were reviewed.

CONCLUSIONS

IBS is a chronic multifactorial disorder that has a negative impact on patient-related quality of life. Genetic factors, psychosociologic factors, alterations in the gut microbiota, and changes in immune, motor, and sensory responses to various stimuli all may be involved in the development of IBS. While pharmacologic therapies for IBS-D have historically been limited (e.g., alosetron), newer therapies (eluxadoline and rifaximin), both approved in the United States in 2015, may be considered for appropriate patients for the management of IBS-D.

IMPLICATIONS FOR PRACTICE

Nurse practitioners play an important role in the diagnosis, care, and management of patients with IBS-D. The goals of therapy should be to reach a correct diagnosis before initiating therapy, provide reassurance to the patient, educate the patient on potential treatment options, improve IBS-D symptoms, minimize risk of harm with treatment, and maximize patient-related quality of life. The authors present a treatment algorithm to guide nurse practitioners on the management of patients with IBS-D.

A meta-analysis and systematic review of the comorbidity between irritable bowel syndrome and bipolar disorder

Irritable bowel syndrome (IBS) and bipolar disorder (BD) are 2 distinct diseases but may share a similar pathophysiology. However, the comorbidity rate of these 2 diseases is unclear. Also, the current practice guidelines suggest prescribing antidepressants to IBS patients. However, this practice may increase the risk of phase-shift to manic episodes in IBS patients comorbid with BD.This study aimed to determine the relationship between IBS and BD through a meta-analysis.Electronic research through PubMed, Medline, ScienceDirect online, ClinicalTrials.gov, and additional resources.The inclusion criteria were studies investigating the prevalence rate of BD in subjects with IBS and control subjects; and articles on clinical trials on humans.Data from included studies were pooled by a random effects model, and possible confounding variables were examined by meta-regression and subgroup analysis.The current study consists of a total of 177,117 IBS patients and 192,092 control subjects extracted from 6 included studies. The prevalence rate of BD was significantly higher in the IBS patients than in the controls (odds ratio = 2.48, 95% confidence interval: 2.35-2.61, P < 0.001). However, the significance persists only in studies from database research, but not from primary studies. In addition, there was no significant association between the prevalence rate of BD in IBS and several clinical variables, including age, female proportion, prevalence of comorbid diabetes, or hypertension.The total number of included studies is small. Moreover, apparently different results from database research and primary research limit the generalization of our findings to a broad population. Also, we could only perform meta-regression on limited clinical variables.Our results support a significantly higher prevalence rate of BD in IBS patients than in controls. Clinicians should be cautious about the risk of phase-shift to manic episodes when prescribing antidepressants in IBS patients under current practice guidelines.

New and emerging therapies for the treatment of irritable bowel syndrome: an update for gastroenterologists

Irritable bowel syndrome is a functional bowel disorder with gastrointestinal symptoms (e.g. abdominal pain, straining, urgency, incomplete evacuation, nausea, and bloating) that occur alongside bowel function alterations (i.e. constipation, diarrhea, or both). Patients with irritable bowel syndrome may also experience comorbid anxiety and depression. Irritable bowel syndrome is common, with a prevalence estimated between 3% and 28%, affecting patient health and quality of life. Patients with moderate or severe irritable bowel syndrome generally seek medical care, whereas those with milder symptoms may choose self-management. Most patients with irritable bowel syndrome receive outpatient care, but irritable bowel syndrome-related hospitalizations do occur. The pathophysiology of irritable bowel syndrome is multifactorial (i.e. genetics, immune components, changes in the gut microbiota, disturbances in physiologic stress response systems, and psychosocial factors). Management of irritable bowel syndrome can include lifestyle changes, dietary interventions, counseling, psychologic medication, and agents that affect gastrointestinal motility. A number of therapies have emerged in recent years with clinical trial data demonstrating efficacy and safety for patients with irritable bowel syndrome, including agents that target gastrointestinal motility (i.e. linaclotide), gastrointestinal opioid receptors (i.e. asimadoline, eluxadoline), and gut microbiota (i.e. rifaximin). Linaclotide has been shown to significantly improve stool frequency and abdominal pain compared with placebo in constipation-predominant irritable bowel syndrome (number needed to treat, 5.1). Asimadoline shows efficacy in patients with moderate-to-severe irritable bowel syndrome-related pain. Rifaximin provided adequate relief of global irritable bowel syndrome symptoms versus placebo for a significantly greater percentage of patients with diarrhea-predominant irritable bowel syndrome (p < 0.001). Management that encompasses all aspects of irritable bowel syndrome (gastrointestinal symptoms) and comorbid psychologic symptoms (e.g. anxiety or depression) is important for improving overall patient health and well-being.

An Epidemiological Study of Neuropathic Pain Symptoms in Canadian Adults

The reported prevalence of neuropathic pain ranges from 6.9% to 10%; however the only Canadian study reported 17.9%. The objective of this study was to describe the epidemiology of neuropathic pain in Canada. A cross-sectional survey was conducted in a random sample of Canadian adults. The response rate was 21.1% (1504/7134). Likely or possible neuropathic pain was defined using a neuropathic pain-related diagnosis and a positive outcome on the Self-Report Leeds Assessment of Neuropathic Symptoms and Signs pain scale (S-LANSS) or the Douleur Neuropathique 4 (DN4) Questions. The prevalence of likely neuropathic pain was 1.9% (S-LANSS) and 3.4% (DN4) and that of possible neuropathic pain was 5.8% (S-LANSS) and 8.1% (DN4). Neuropathic pain was highest in economically disadvantaged males. There is a significant burden of neuropathic pain in Canada. The low response rate and a slightly older and less educated sample than the Canadian population may have led to an overestimate of neuropathic pain. Population prevalence varies by screening tool used, indicating more work is needed to develop reliable measures. Population level screening targeted towards high risk groups should improve the sensitivity and specificity of screening, while clinical examination of those with positive screening results will further refine the estimate of prevalence.

Boundary Negotiating Artifacts in Personal Informatics: Patient-Provider Collaboration with Patient-Generated Data

Patient-generated data is increasingly common in chronic disease care management. Smartphone applications and wearable sensors help patients more easily collect health information. However, current commercial tools often do not effectively support patients and providers in collaboration surrounding these data. This paper examines patient expectations and current collaboration practices around patient-generated data. We survey 211 patients, interview 18 patients, and re-analyze a dataset of 21 provider interviews. We find that collaboration occurs in every stage of self-tracking and that patients and providers create boundary negotiating artifacts to support the collaboration. Building upon current practices with patient-generated data, we use these theories of patient and provider collaboration to analyze misunderstandings and privacy concerns as well as identify opportunities to better support these collaborations. We reflect on the social nature of patient-provider collaboration to suggest future development of the stage-based model of personal informatics and the theory of boundary negotiating artifacts.

Altered gastrointestinal microbiota in irritable bowel syndrome and its modification by diet: probiotics, prebiotics and the low FODMAP diet

Irritable bowel syndrome (IBS) is a functional bowel disorder characterised by abdominal pain or discomfort with disordered defecation. This review describes the role of the gastrointestinal (GI) microbiota in the pathogenesis of IBS and how dietary strategies to manage symptoms impact on the microbial community. Evidence suggests a dysbiosis of the luminal and mucosal colonic microbiota in IBS, frequently characterised by a reduction in species of Bifidobacteria which has been associated with worse symptom profile. Probiotic supplementation trials suggest intentional modulation of the GI microbiota may be effective in treating IBS. A smaller number of prebiotic supplementation studies have also demonstrated effectiveness in IBS whilst increasing Bifidobacteria. In contrast, a novel method of managing IBS symptoms is the restriction of short-chain fermentable carbohydrates (low fermentable oligosaccharides, disaccharides, monosaccharides and polyols (FODMAP) diet). Studies consistently demonstrate clinical effectiveness of the low FODMAP diet in patients with IBS. However, one unintentional consequence of this dietary intervention is its impact on the microbiota. This leads to an interesting paradox; namely, increasing luminal Bifidobacteria through probiotic supplementation is associated with a reduction in IBS symptoms while in direct conflict to this, the low FODMAP diet has clinical efficacy but markedly reduces luminal Bifidobacteria concentration. Given the multifactorial aetiology of IBS, the heterogeneity of symptoms and the complex and diverse nature of the microbiome, it is probable that both interventions are effective in patient subgroups. However combination treatment has never been explored and as such, presents an exciting opportunity for optimising clinical management, whilst preventing potentially deleterious effects on the GI microbiota.

Diagnosis and treatment of diarrhea-predominant irritable bowel syndrome

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

Diagnosis and treatment of diarrhea-predominant irritable bowel syndrome

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

Clinically Diagnosed Acute Diverticulitis in Outpatients: Misdiagnosis in Patients with Irritable Bowel Syndrome

BACKGROUND

Physicians often diagnose diverticulitis and prescribe antibiotics in outpatients with abdominal pain and tenderness without other evidence.

AIM

We investigated the misattribution of irritable bowel syndrome (IBS) symptoms to diverticulitis in outpatients.

METHODS

In patients diagnosed with diverticulitis and dispensed antibiotics in an integrated healthcare system, we retrospectively compared 15,846 outpatients managed without computed tomography (CT) versus 3750 emergency department/inpatients who had CT. We assessed demographics and past history, including 17 symptom-based somatic and 11 mental disorders and three somatic-mental comorbidity pairs (dyads) coded over 3 years and seven drug classes dispensed over 1 year before diagnosis.

RESULTS

Univariate analysis showed small intergroup demographic differences. Outpatients had increases in prior diverticulitis, including outpatient-managed episodes, total somatic diagnoses (p < .0001), eight somatic and three mental disorders (p ≤ .015), all three dyads (p ≤ .05), and dispensing of three drug classes (p ≤ .016). IBS had been diagnosed in 2399 (15.1 %) outpatients versus 361 (9.6 %) emergency department/inpatients (p < .0001), the greatest increase in any comorbidity. Emergency department/inpatients had no somatic comorbidity more often but more alcohol dependence, non-dependent drug abuse, and opioid dispensing (p ≤ .05). Regression analysis revealed outpatient care was independently positively associated with younger age, non-Hispanic white race/ethnicity, less Charlson comorbidity, diverticulitis history, IBS, chest pain, dyspepsia, fibromyalgia, low back pain, migraine, acute reaction to stress, and antispasmodic and anxiolytic dispensing and negatively associated with non-dependent drug abuse and opioid dispensing (p ≤ .0226).

CONCLUSIONS

Multiple types of indirect and concordant evidence suggest misattribution of IBS pain to diverticulitis and unnecessary antibiotic therapy in outpatients.

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

BACKGROUND

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

PURPOSE

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

A framework for self-experimentation in personalized health

OBJECTIVE

To describe an interdisciplinary and methodological framework for applying single case study designs to self-experimentation in personalized health. The authors examine the framework's applicability to various health conditions and present an initial case study with irritable bowel syndrome (IBS).

METHODS AND MATERIALS

An in-depth literature review was performed to develop the framework and to identify absolute and desired health condition requirements for the application of this framework. The authors developed mobile application prototypes, storyboards, and process flows of the framework using IBS as the case study. The authors conducted three focus groups and an online survey using a human-centered design approach for assessing the framework's feasibility.

RESULTS

All 6 focus group participants had a positive view about our framework and volunteered to participate in future studies. Most stated they would trust the results because it was their own data being analyzed. They were most concerned about confounds, nonmeaningful measures, and erroneous assumptions on the timing of trigger effects. Survey respondents (N = 60) were more likely to be adherent to an 8- vs 12-day study length even if it meant lower confidence results.

DISCUSSION

Implementation of the self-experimentation framework in a mobile application appears to be feasible for people with IBS. This framework can likely be applied to other health conditions. Considerations include the learning curve for teaching self-experimentation to non-experts and the challenges involved in operationalizing and customizing study designs.

CONCLUSION

Using mobile technology to guide people through self-experimentation to investigate health questions is a feasible and promising approach to advancing personalized health.

Guided self-help interventions for irritable bowel syndrome: a systematic review and meta-analysis

OBJECTIVE

Although irritable bowel syndrome (IBS) is highly prevalent and is accompanied by high costs for respective healthcare systems, the data on treatment effectiveness are limited. Current treatment methods have limitations in terms of side effects and availability. Guided self-help (GSH) might be an easily accessible and cost-effective treatment alternative. This study is the first systematic review and meta-analysis of GSH interventions for IBS.

METHODS

Using electronic databases (MEDLINE, SCOPUS, PsycINFO, and Web of Science), we performed a systematic search for randomized-controlled trials. Using a random-effect model, we calculated the pooled standardized mean differences (SMDs) of GSH on IBS symptom severity (primary outcome) and quality of life (secondary outcome). We additionally examined the moderating effects of online-based interventions and face-to-face therapist contact by applying mixed models.

RESULTS

A systematic literature search identified 10 eligible randomized-controlled trials, including 886 participants. Compared with the control conditions, the effect size was medium for the decrease in IBS symptom severity (SMD=0.72; 95% confidence interval: 0.34-1.08) and large for the increase in patients' quality of life (SMD=0.84; 95% confidence interval: 0.46-1.22). Neither treatment format nor face-to-face contact was a predictor of therapy outcomes in between-group analyses. In contrast, within-group analyses led to the conclusion that online-based interventions are more effective than other self-help formats.

CONCLUSION

GSH is an effective alternative for the treatment of IBS. As GSH methods are easy to implement, it seems sensible to integrate GSH into clinical practice.

LIMITATIONS

With respect to the high study heterogeneity, the number of studies included was relatively small.

Predictive factors for the diagnosis of irritable bowel syndrome in a large cohort of 440,822 young adults

BACKGROUND

The prevalence of irritable bowel syndrome (IBS) in the community has been reported in numerous cross-sectional surveys. However, little is known about the incidence and predictive factors for the clinical diagnosis of IBS.

METHODS

We examined the association of socioeconomic, anthropometric, and occupational factors with the incidence of IBS in a cohort of 440,822 young Israeli adults aged 18 to 39 who served in active military service during the years 2005 to 2011.

RESULTS

During the follow-up of 1,925,003 person-years, IBS was diagnosed de novo in 976 patients, giving an incidence rate of 221:100,000 (0.2%) person-years for the diagnosis of IBS. On multivariable Cox analysis, higher socioeconomic status [hazard ratio (HR) 1.629; 95% confidence interval (CI), 1.328-1.999; P<0.0001], Israeli birth (HR 1.362; 95% CI, 1.084-1.712; P=0.008), Jewish ethnicity (HR 2.089; 95% CI, 1.344-3.248; P=0.001), education ≥than 11 years (HR 1.674; 95% CI, 1.019-2.751; P=0.042), and a noncombat military position (HR 1.196; 95% CI, 1.024-1.397; P=0.024) were found to be risk factors for the diagnosis or for the worsening of IBS. Overweight (HR 0.744; 95% CI, 0.589-0.941; P=0.014), obesity (HR 0.698; 95% CI, 0.510-0.95; P=0.025), living in a rural settlement (HR 0.705; 95% CI, 0.561-0.886; P=0.003), and Middle Eastern (HR 0.739; 95% CI, 0.617-0.884; P=0.001,) or North African and Ethiopian origin (HR 0.702; 95% CI, 0.585-0.842; P<0.001) were found to be protective for the diagnosis or the worsening of IBS.

CONCLUSIONS

This study provides novel data on the socioeconomic, anthropometric, and occupational factors predictive for IBS development. The predictive factors for IBS diagnosis may point to the fact that stress had a lower impact on IBS incidence in our study cohort.

Pain in Canadian Veterans: analysis of data from the Survey on Transition to Civilian Life

In the United States, extensive research has been conducted investigating chronic pain among Veterans; however, such research has not been conducted among Canadians who served in the military. Accordingly, this study aimed to investigate the prevalence of chronic pain among Canadian Veterans, and to determine correlates of chronic pain in this population. Data for this study were obtained from the Survey on Transition to Civilian Life; 3154 Veterans released from service between January 1, 1998 and December 31, 2007 responded to the survey.

BACKGROUND:

Little is known about the prevalence of chronic pain among Veterans outside the United States.

OBJECTIVE:

To describe the prevalence of chronic pain and associated sociodemographic, health behaviour, employment/income, disability, and physical and mental health factors in Canadian Veterans.

METHODS:

The 2010 Survey on Transition to Civilian Life included a nationally representative sample of 3154 Canadian Armed Forces Regular Force Veterans released from service between 1998 and 2007. Data from a telephone survey of Veterans were linked with Department of National Defence and Veterans Affairs Canada administrative databases. Pain was defined as constant/reoccurring pain (chronic pain) and as moderate/severe pain interference with activities.

RESULTS:

Forty-one percent of the population experienced constant chronic pain and 23% experienced intermittent chronic pain. Twenty-five percent reported pain interference. Needing help with tasks of daily living, back problems, arthritis, gastrointestinal conditions and age ≥30 years were independently associated with chronic pain. Needing help with tasks of daily living, back problems, arthritis, mental health conditions, age ≥30 years, gastrointestinal conditions, low social support and noncommissioned member rank were associated with pain interference.

CONCLUSIONS:

These findings provide evidence for agencies and those supporting the well-being of Veterans, and inform longitudinal studies to better understand the determinants and life course effects of chronic pain in military Veterans.

NPSR1 polymorphisms influence recurrent abdominal pain in children: a population-based study

BACKGROUND

Recurrent abdominal pain (RAP) occurs frequently among children and is one of the cardinal symptoms of functional gastrointestinal disorders (FGID). The mechanisms of visceral pain and RAP are not fully understood. A heritable component has been demonstrated and a few candidate genes proposed. NPSR1 encodes the receptor for neuropeptide S (NPS) and NPS-NPSR1 signaling is involved in anxiety, inflammation, and nociception. NPSR1 polymorphisms are associated with asthma and chronic inflammatory diseases, but also with IBS-related intermediate phenotypes such as colonic transit time and rectal sensory ratings. Here, we sought to determine whether genetic variability in the NPSR1 gene influences the presence of RAP in children.

METHODS

Twenty-eight single-nucleotide polymorphisms (SNPs) in the NPSR1 gene region were successfully genotyped in 1744 children from the Swedish birth cohort BAMSE. Questionnaire information was used to define RAP as episodes of abdominal pain occurring at least once a month in 12-year-olds.

KEY RESULTS

The prevalence of RAP was 9% in BAMSE. Association with RAP was observed for seven NPSR1 SNPs, five of which withstood false discovery rate (FDR) correction for multiple testing (best p = 0.00054, OR: 1.55 for SNP rs2530566). The associated SNPs all map in a putative regulatory region upstream NPSR1, where they may exert their genetic effects through the modulation of gene expression.

CONCLUSIONS & INFERENCES

Genetic variation at the NPSR1 locus impacts children's predisposition to RAP episodes in a Swedish population.

Effect of antidepressants and psychological therapies, including hypnotherapy, in irritable bowel syndrome: systematic review and meta-analysis

OBJECTIVES

Irritable bowel syndrome (IBS) is a chronic functional gastrointestinal disorder. Evidence relating to the treatment of this condition with antidepressants and psychological therapies continues to accumulate.

METHODS

We performed an updated systematic review and meta-analysis of randomized controlled trials (RCTs). MEDLINE, EMBASE, and the Cochrane Controlled Trials Register were searched (up to December 2013). Trials recruiting adults with IBS, which compared antidepressants with placebo, or psychological therapies with control therapy or "usual management," were eligible. Dichotomous symptom data were pooled to obtain a relative risk (RR) of remaining symptomatic after therapy, with a 95% confidence interval (CI).

RESULTS

The search strategy identified 3,788 citations. Forty-eight RCTs were eligible for inclusion: thirty-one compared psychological therapies with control therapy or "usual management," sixteen compared antidepressants with placebo, and one compared both psychological therapy and antidepressants with placebo. Ten of the trials of psychological therapies, and four of the RCTs of antidepressants, had been published since our previous meta-analysis. The RR of IBS symptom not improving with antidepressants vs. placebo was 0.67 (95% CI=0.58-0.77), with similar treatment effects for both tricyclic antidepressants and selective serotonin reuptake inhibitors. The RR of symptoms not improving with psychological therapies was 0.68 (95% CI=0.61-0.76). Cognitive behavioral therapy, hypnotherapy, multicomponent psychological therapy, and dynamic psychotherapy were all beneficial.

CONCLUSIONS

Antidepressants and some psychological therapies are effective treatments for IBS. Despite the considerable number of studies published in the intervening 5 years since we last examined this issue, the overall summary estimates of treatment effect have remained remarkably stable.

Novel Testing Enhances Irritable Bowel Syndrome Medical Management: The IMMINENT Study

Primary Study Objective:

To evaluate the economic utility of a fecal biomarker panel structured to suggest alternative, treatable diagnoses in patients with symptoms of irritable bowel syndrome (IBS) by quantifying, comparing, and contrasting health service costs between tested and non-tested patients.

Study Design:

Retrospective, matched cohort study comparing direct medical costs for IBS patients undergoing fecal biomarker testing with those of matched control subjects.

Methods:

We examined de-identified medical and pharmacy claims of a large American pharmacy benefit manager to identify plan members who underwent panel testing, were eligible for covered benefits for at least 180 days prior to the test date, and had data available for 30, 90, and 365 days after that date. We used propensity score matching to develop population-based control cohorts for each tested cohort, comprised of records with IBS-related diagnoses but for which panel testing was not performed. Primary outcome measures were diagnostic and medical services costs as determined from claims data.

Results:

Two hundred nine records from tested subjects met inclusion criteria. The only significant baseline differences between groups were laboratory costs, which were significantly higher in each tested cohort. At each follow-up time point, total medical and gastrointestinal procedural costs were significantly higher in non-tested cohorts. Within tested cohorts, costs declined significantly from baseline, while costs rose significantly in non-tested control cohorts; these differences were also significant between groups at each time point.

Conclusions:

Structured fecal biomarker panel testing was associated with significantly lower medical and gastrointestinal procedural costs in this study of patients with IBS symptoms.

Association between depression and irritable bowel syndrome in elderly patients

AIM: To investigate the association between depression and irritable bowel syndrome (IBS) in elderly patients.

METHODS: Seventy-four elderly patients (60-75 years, and > 75 years) and seventy-four non-elderly patients (< 60 yeas) with IBS treated at Department of Gastroenterology of the Affiliated Puai Hospital of Tongji Medical College of Huazhong University of Science and Technology from May 2010 to February 2013 were recruited. The patients were assessed using the ZUNG self-rating depression scale (SDS) and irritable bowel syndrome-quality of life measure (IBS-QOL) to predict the association between SDS and IBS-QOL in each group.

RESULTS: The SDS score in elderly patients was significantly higher than that in non-elderly patients (< 60 years and 60-75 years: 50.51 ± 6.60 vs 62.29 ± 7.34, P < 0.001; < 60 years and > 75 years: 50.51 ± 6.60 vs 63.72 ± 5.74, P < 0.001), but there was no significant difference in the two subgroups of elderly patients (60-75 years and > 75 years: 62.29 ± 7.34 vs 63.72 ± 5.74, P > 0.5). The majority of IBS types in the > 75 years group belonged to IBS-C, and the percentage of patients with IBS-C in the > 75 years group was significantly different from those in the <60 years and 60-75 years groups (both P < 0.05), but there were no difference between the latter two groups. There were negative correlations between SDS score and IBS-QOL score (P < 0.001) in each group, and the IBS-QOL score in elderly patients was significantly lower than that in non-elderly patients (P < 0.001), although there was no difference between the two subgroups of elderly patients (P > 0.5).

CONCLUSION: Depression in elderly patients is prone to initiate irritable bowel syndrome, compared with non-elderly patients. The dominant IBS type in elderly patients is IBS-C, which severely affects the patient's quality of life.

Regional differences in healthcare delivery for gastroparesis

AIM

Few studies have examined the effects of various interventions in gastroparesis. The goal of the present study was to determine whether inpatient management and outcomes differed among states across the United States.

METHODS

Using population statistics and the State Inpatient Database (Agency for Healthcare Research and Quality), regional differences in admissions for gastroparesis, inpatient mortality, length of stay, nursing home transfers, and rates of endoscopy, gastrostomy placement, and nutritional support were assessed.

RESULTS

Admissions for gastroparesis ranged from 24.3 ± 0.8/100,000 in Utah to 117.1 ± 9.7/100,000 in Maryland, with mortality rates similarly varying fourfold from 0.5 ± 0.1/100,000 in Colorado to 2.3 ± 0.1/100,000 in Florida. Intervention rates differed between states (endoscopy: 6.8 ± 0.8 % in Wyoming versus 23.1 ± 0.4 % in Florida; gastrostomy: 0.8 ± 0.1 % in North Carolina versus 3.3 ± 0.8 % in Hawaii; nutritional support: 1.2 ± 0.2 % in West Virginia versus 7.0 ± 0.6 % in New Jersey). Admissions rates were independently predicted by high overall hospitalizations within a state. Higher population density, median incomes and admissions to for-profit hospitals correlated with endoscopy rates. Coexisting heart failure and male gender were associated with higher likelihood of gastrostomy placement, while initiation of nutritional support was predicted by physician supply and insurance status. Age cohort, Medicare coverage, poverty rates and endoscopic testing independently predicted mortality, while length of stay correlated with diagnostic and therapeutic interventions.

CONCLUSIONS

There is a significant variability in admissions, interventions and outcomes for gastroparesis. While biological factors, such as comorbidities and age, contribute to this variability, the data suggest that socioeconomic variables significantly affect approaches to gastroparesis treatment in the United States.