Systematic review: instruments to assess abdominal pain in irritable bowel syndrome

An examination of resting-state functional connectivity in patients with active Crohn's disease

Background

Alterations in resting state functional connectivity (rs-FC) in Crohn's Disease (CD) have been documented in default mode network (DMN) and frontal parietal network (FPN) areas, visual, cerebellar, salience and attention resting-state-networks (RSNs), constituting a CD specific neural phenotype. To date, most studies are in patients in remission, with limited studies in active disease.

Methods

Twenty five active CD cases and 25 age-, BMI- and gender-matched healthy controls (HC) were recruited to a resting-state-functional Magnetic Resonance Imaging (rs-fMRI) study. Active disease was defined as C-reactive protein>5 mg/dL, faecal calprotectin>250 μg/g, or through ileocolonoscopy or MRE. rs-fMRI data were analysed using independent component analysis (ICA) and dual regression. Differences in RSNs between HCs and active CD were assessed, and rs-FC was associated with disease duration and abdominal pain.

Results

Increased connectivity in the FPN (fusiform gyrus, thalamus, caudate, posterior cingulate cortex, postcentral gyrus) and visual RSN (orbital frontal cortex) were observed in CD versus HC. Decreased activity was observed in the salience network (cerebellum, postcentral gyrus), DMN (parahippocampal gyrus, cerebellum), and cerebellar network (occipital fusiform gyrus, cerebellum) in CD versus HCs. Greater abdominal pain scores were associated with lower connectivity in the precuneus (visual network) and parietal operculum (salience network), and higher connectivity in the cerebellum (frontal network). Greater disease duration was associated with greater connectivity in the middle temporal gyrus and planum temporale (visual network).

Conclusion

Alterations in rs-FC in active CD in RSNs implicated in cognition, attention, emotion, and pain may represent neural correlates of chronic systemic inflammation, abdominal pain, disease duration, and severity.

Abdominal Pain in Inflammatory Bowel Disease: An Evidence-Based, Multidisciplinary Review

Abdominal pain is one of the most common and impactful symptoms associated with inflammatory bowel disease (IBD), including both Crohn's disease and ulcerative colitis. A great deal of research has been undertaken over the past several years to improve our understanding and to optimize management of this issue. Unfortunately, there is still significant confusion about the underlying pathophysiology of abdominal pain in these conditions and the evidence underlying treatment options in this context. There is also a relative paucity of comprehensive reviews on this topic, including those that simultaneously evaluate pharmacological and nonpharmacological therapeutic options. In this review, our multidisciplinary team examines evidence for various currently available medical, surgical, and other analgesic options to manage abdominal pain in IBD.

Factors influencing rectal hypersensitivity in irritable bowel syndrome: A systematic review and meta-analysis

BACKGROUND

A frequent, although not universal, feature of irritable bowel syndrome (IBS) is heightened sensitivity to mechanical stimulation of the rectum, termed rectal hypersensitivity (RH). Differences in RH-based on sex, IBS subtype, IBS diagnostic criteria and age of population studied are incompletely understood. We aimed to determine whether IBS population had lower pain thresholds than healthy controls.

METHODS

We searched MEDLINE and EMBASE databases (1970-2021). Prospective studies that compared pain/discomfort thresholds to mechanical rectal stimuli in IBS and healthy controls were included. Data were pooled for meta-analyses and effect sizes were calculated with 95% confidence interval (CIs).

RESULTS

Our search strategy identified 809 studies of which 32 studies met the inclusion criteria. Reduced rectal pain thresholds was more common in IBS patients compared to healthy controls with an effect size of 1.00 95% CIs (0.77-1.24) (p < 0.0001) (I²  = 78.6%). The pediatric IBS population had lower pain thresholds than adult IBS populations (p = 0.05) but no difference based on IBS diagnostic criteria, subtype or sex.

CONCLUSION & INFERENCES

The results suggest that reduced rectal pain threshold to experimental stimulation is far more common in IBS patients than healthy controls. Further research is required to understand the pathophysiological and therapeutic implications of rectal sensitivity such as its role in measuring response to treatment and prognosis in IBS.

Randomised clinical trial: Psychological intervention improves work productivity and daily activity by reducing abdominal pain and fatigue in Crohn's disease

BACKGROUND

Chronic abdominal pain and fatigue are characteristics of Crohn's disease (CD) and contribute to functional impairments.

AIMS

To examine whether CD-tailored cognitive-behavioural and mindfulness intervention (COBMINDEX) is effective in reducing abdominal pain and fatigue in patients with CD and whether changes in abdominal pain and fatigue mediate any beneficial effects of COBMINDEX on impairments in work productivity and daily activities.

METHODS

This is a secondary analysis of a parallel-group multicentre randomised controlled trial. Patients with mild-to-moderate CD (n = 142) were randomised into either intervention group receiving COBMINDEX, or control group receiving treatment-as-usual for 3 months followed by COBMINDEX. Complete data were collected from 120 patients (34.0 ± 10.7 years, 62.5% female, intervention = 60, control = 60). Analysis of covariance assessed group differences in 3-month follow-up scores, controlling for baseline scores. Multiple parallel mediation analysis assessed the proposed mechanisms for the entire sample.

RESULTS

The intervention group demonstrated significantly lower levels of abdominal pain (F = 17.46, p < 0.001, η² _p  = 0.13), fatigue (F = 7.26, p = 0.008, η² _p  = 0.06) and impairments at work (F = 4.82, p = 0.032, η² _p  = 0.07) and daily activities (F = 6.26, p = 0.014, η² _p  = 0.05), compared with treatment-as-usual. Moreover, changes in abdominal pain and fatigue significantly mediated the beneficial effects of COBMINDEX on patients' work productivity (b = -9.90, SE = 2.86, 95% CI: -16.11 to -4.94) and daily activities (b = -9.65, SE = 1.91, 95% CI: -13.77 to 6.35), independent of changes in disease activity.

CONCLUSIONS

COBMINDEX is effective at reducing abdominal pain and fatigue in patients with CD, which in turn leads to improvement in functioning. Clinicians should incorporate screening for severe abdominal pain and fatigue and consider offering cognitive-behavioural and mindfulness training.

CLINICALTRIALS

gov, Number: NCT05085925. Ministry of Health in Israel (https://my.health.gov.il/CliniTrials/Pages/MOH_2020-02-24_008721.aspx).

Multicenter prospective study showing a high gastrointestinal symptom burden in cystic fibrosis

BACKGROUND AND AIMS

People with cystic fibrosis (PwCF) suffer from gastrointestinal (GI) symptoms affecting their quality of life (QOL). Despite the relevance of GI symptoms to the overall health of PwCF, a paucity of studies only have comprehensively assessed the prevalence, severity and QOL of GI symptoms in both children and adults with Cystic Fibrosis (CF).

METHODS

Eligible participants ≥2 years of age across 26 US CF centers were followed for 4 weeks. Three validated GI electronic patient-reported outcome measures (ePROMs) with a recall period of 2 weeks and a stool-specific questionnaire were administered weekly over four weeks. Total and domain scores of ePROMs were evaluated overall and in subgroups using linear mixed-effect models.

RESULTS

Of 402 enrolled, 58% were ≥ 18 years of age (52% male). The mean (SD) of the total score for PAC-SYM was 0.52 (0.55), for PAGI-SYM was 0.63 (0.67), and for PAC-QOL was 0.67 (0.55). For specific ePROM questions, prevalence of moderate to very severe symptoms were as follows: straining (20.3%), fullness (18.3%), incomplete bowel movements (17.1%), bloating (16.4%), distension (16.4%), abdominal pain (upper-5.1%, lower-7.5%). Comparing participants ≥18 versus <18, a higher prevalence of bloating (63.7% versus 27.3%), lower abdominal pain (39.8% vs 26.2%), stomach fullness (75.6% versus 56.2%), and abdominal distension (60.2% versus 34.9%) was found. Both age groups reported high treatment dissatisfaction as measured with PAC-QOL, mean 1.39 (95% CI: 1.30, 1.47).

CONCLUSION

GI symptoms were reported in all age ranges irrespective of gender, with higher prevalence observed amongst older and female subgroups. Dissatisfaction with GI targeted treatments were reported in a large proportion of participants despite therapy, highlighting an unmet need for clinical interventions.

CLINICALTRIALS

GOV: NCT03801993.

Multi-omics for biomarker approaches in the diagnostic evaluation and management of abdominal pain and irritable bowel syndrome: what lies ahead

Reliable biomarkers for common disorders of gut-brain interaction characterized by abdominal pain, including irritable bowel syndrome (IBS), are critically needed to enhance care and develop individualized therapies. The dynamic and heterogeneous nature of the pathophysiological mechanisms that underlie visceral hypersensitivity have challenged successful biomarker development. Consequently, effective therapies for pain in IBS are lacking. However, recent advances in modern omics technologies offer new opportunities to acquire deep biological insights into mechanisms of pain and nociception. Newer methods for large-scale data integration of complementary omics approaches have further expanded our ability to build a holistic understanding of complex biological networks and their co-contributions to abdominal pain. Here, we review the mechanisms of visceral hypersensitivity, focusing on IBS. We discuss candidate biomarkers for pain in IBS identified through single omics studies and summarize emerging multi-omics approaches for developing novel biomarkers that may transform clinical care for patients with IBS and abdominal pain.

Effect of intracolonic volume on gastric sensory-motor responses in constipation-predominant irritable bowel syndrome

BACKGROUND

Interaction between gut stimuli may induce symptom overlap in patients with functional gastrointestinal disorders. The aim is to determine the effect of increased volumes of colonic contents on gastric sensory/motor responses and satiety in patients with constipation-predominant irritable bowel syndrome (IBS-C) and overlapping dyspeptic symptoms, and a cohort of healthy subjects.

METHODS

In 15 patients with IBS-C and 10 healthy subjects, the effect of real versus sham colonic filling with gas (1080 ml) on gastric sensitivity (measured by stepwise distensions of the stomach), gastric compliance, abdominal perception, and nutrient drink tolerance was studied on separate days.

RESULTS

In healthy subjects, colonic gas filling induced an increment in gastric sensitivity to distension (mean score 2.0 ± 0.2 before, and 3.0 ± 0.4 after; p = 0.038). In IBS, basal sensitivity was greater and remained unchanged after colonic gas filling (score 4.0 ± 0.1 and 3.8 ± 0.3, respectively; p < 0.001 vs. basal in health). Colonic gas infusion induced abdominal symptoms that were significantly greater in IBS-C (score 2.6 ± 0.1) than in health (score 1.7 ± 0.4; p = 0.027), with minor changes in gastric tone, and no changes in gastric compliance in both groups. Colonic filling produced a profound reduction in nutrient drink tolerance in IBS (791 ± 87 ml sham filling, 491 ± 58 ml gas filling; p < 0.001) but only a minor reduction in health (940 ± 70 ml sham filling, 860 ± 94 ml gas filling; p = 0.223).

CONCLUSIONS & INFERENCES

The volume of the colonic contents modulates satiety in patients with IBS-C, due to a general visceral pan-hypersensitivity. These effects should be considered in the choice of treatment for constipation in these patients.

Application of capsule endoscopy in patients with chronic and recurrent abdominal pain: Abbreviated running title: capsule endoscopy in abdominal pain

OBJECTIVE

The incidence of chronic and recurrent abdominal pain increases every year, while the diagnosis is still unsatisfactory even after a number of check-ups. This study aimed to evaluate the diagnosis value of capsule endoscopy in patients suffering from chronic and recurrent abdominal pain.

METHODS

A retrospective case study was performed in 80 chronic and recurrent abdominal pain patients at Xiangyang Central Hospital from January 2013 to November 2017. Meanwhile, diagnoses by capsule endoscopy were collected for analysis.

RESULTS

Abnormal findings were found in 54 of 80 (67.5%) patients. The findings in chronic and recurrent abdominal pain patients include small intestinal erosion and congestion, small intestinal ulcers, small intestinal parasites, small intestinal vascular malformations, small intestinal polyps, small intestinal diverticulum, and small intestinal lymphangiectasia. There were no immediate significant side effects without being reported up to 1 month after ingestion of the capsule. The capsule was evacuated by all patients.

CONCLUSIONS

Capsule endoscopy has a great value in the diagnosis of chronic and recurrent abdominal pain with satisfactory safety and less pain for patients. Inflammatory lesions and ulcers in the small intestine account for the majority of positive findings in these patients.

Measurement of Pain and Related Symptoms in Irritable Bowel Syndrome: The Use of Validated Pain Measurement Tools

This paper reviews the tools available to assess outcomes of treatment in irritable bowel syndrome, especially the effect on abdominal pain. Tools were identified through a wide-ranging scrutiny of PubMed and Google Scholar, together with a review of further references quoted in those publications. It critically considers their development, relevance and reliability. The Irritable Bowel Severity Scoring System (IBS-SSS) was the first simple method of monitoring the progress of the disease and its treatment. It led on to other instruments, such as The Irritable Bowel Syndrome Quality of Life (IBS-QOL). It is easier to read and faster to complete than the IBS-SSS., However, these and other tools were developed for English speaking populations. This review considers the impact of ethnicity and gender, together with the lack of information on the effect of age on the potential validity of these tools in other populations. Issues with the adequacy and appropriateness of translations of such tools are discussed. The overall conclusion is that there are few tools which meet the criteria necessary to place confidence in their validity as appropriate measures of patient outcomes.

Effectiveness of Non-Pharmacological Interventions for Irritable Bowel Syndrome: A Systematic Review

Introduction

Given the complexity of the therapeutic management of irritable bowel syndrome (IBS), alternative non-pharmacological therapies are frequently offered to patients. The aim of this study was to conduct a systematic review in order to establish the current evidence base for non-pharmacological interventions (body-directed and mind-body therapies) in the management of IBS.

Materials and Methods

The literature was searched in several electronic databases (PubMed (including Medline), Web of Science (Clarivate Analytics), Scopus (Elsevier), ScienceDirect (Elsevier), Cochrane Library (Wiley), and Wiley Online Library (Wiley)) for randomized controlled trials (RCTs) published in the English language from 1990 to 2020. Effectiveness outcomes were examined through the change in overall IBS symptoms or abdominal pain up to 12 months after treatment.

Results

11 studies (parallel-group RCTs) were identified that enrolled 1590 participants in total. Body-directed therapies (acupuncture and osteopathic medicine) showed a beneficial effect compared with standard medical treatment for overall IBS symptoms at 6 months follow-up, while no study found any difference between body-directed and sham therapies for abdominal pain or overall IBS symptoms. It was not possible to conclude whether hypnotherapy was superior to standard medical treatment or supportive therapy for overall IBS symptoms or abdominal pain due to discordant results.

Conclusions

Although body-directed therapies such as acupuncture and osteopathic medicine may be beneficial for overall IBS symptoms, higher-quality RCTs are needed to establish the clinical benefit of non-pharmacological interventions for IBS. An important challenge will be the definition of the optimal control groups to be used in non-pharmacological trials.

Effect of Low FODMAPs Diet on Irritable Bowel Syndromes: A Systematic Review and Meta-Analysis of Clinical Trials

We conducted a meta-analysis exploring the effect of a low fermentable oligo-, di-, monosaccharides, and polyols diet (LFD) on the overall symptoms, quality of life, and stool habits of irritable bowel syndrome (IBS) patients. The meta-analysis was performed using a random-effects method. The effect size was presented as weighted standardized mean difference (SMD) and 95% confidence interval (CI). Subgroup analyses were conducted to determine the potential effects of covariates on the outcome. Twenty-two papers were included. The LFD group showed a moderate reduction in symptom severity and a slight improvement in quality of life compared to the control group (SMD, −0.53 and 0.24; 95% CI, −0.68, −0.38 and 0.02, 0.47, respectively). IBS symptom improvement was consistent between subgroups stratified according to proportions of female patients, study durations, IBS subtypes, assessment methods, and control interventions. Three studies regarding stool habits change in IBS-D patients showed a significant decrease in stool frequency (mean differences [MD], −5.56/week; 95% CI, −7.40, −3.72) and a significant improvement in stool consistency (MD, −0.86; 95% CI, −1.52, −0.19) in the LFD group compared to the control group. This is the most updated meta-analysis including studies that adopted diverse control interventions such as dietary interventions, supplementation, habitual diets, and lifestyle changes.

An objective approach to assess colonic pain in mice using colonometry

The present study presents a non-surgical approach to assess colonic mechanical sensitivity in mice using colonometry, a technique in which colonic stretch-reflex contractions are measured by recording intracolonic pressures during saline infusion into the distal colon in a constant rate. Colonometrical recording has been used to assess colonic function in healthy individuals and patients with neurological disorders. Here we found that colonometry can also be implemented in mice, with an optimal saline infusion rate of 1.2 mL/h. Colonometrograms showed intermittent pressure rises that was caused by periodical colonic contractions. In the sceneries of colonic hypersensitivity that was generated post 2,4,6-trinitrobenzene sulfonic acid (TNBS)-induced colonic inflammation, following chemogenetic activation of primary afferent neurons, or immediately after noxious stimulation of the colon by colorectal distension (CRD), the amplitude of intracolonic pressure (A_ICP) was markedly elevated which was accompanied by a faster pressure rising (ΔP/Δt). Colonic hypersensitivity-associated A_ICP elevation was a result of the enhanced strength of colonic stretch-reflex contraction which reflected the heightened activity of the colonic sensory reflex pathways. The increased value of ΔP/Δt in colonic hypersensitivity indicated a lower threshold of colonic mechanical sensation by which colonic stretch-reflex contraction was elicited by a smaller saline infusion volume during a shorter period of infusion time. Chemogenetic inhibition of primary afferent pathway that was governed by Nav1.8-expressing cells attenuated TNBS-induced up-regulations of A_ICP, ΔP/Δt, and colonic pain behavior in response to CRD. These findings support that colonometrograms can be used for analysis of colonic pain in mice.

Subtypes and Severity of Irritable Bowel Syndrome Are Not Related to Patients' Self-Reported Dietary Triggers: Results From an Online Survey in Dutch Adults

BACKGROUND

Diet plays an important role in symptom management of irritable bowel syndrome (IBS). However, current diet therapies are not optimal nor successful for everyone.

OBJECTIVE

To investigate whether subgroups based on IBS subtypes or severity identify different self-reported dietary triggers, and whether these are associated with severity and psychological factors.

DESIGN

Online cross-sectional survey PARTICIPANTS: Patients with IBS (n = 1601) who fulfilled the Rome IV criteria or had an IBS diagnosis.

MAIN OUTCOMES

Self-reported response to 44 preselected dietary triggers, IBS quality of life, and anxiety and depression. Subgroups were based on subtypes or severity.

STATISTICAL ANALYSIS

Response to dietary triggers was analyzed using multiple correspondence analysis. Moreover, a food score was calculated to quantify the number and severity of responses to dietary triggers.

RESULTS

Response to greasy foods, onions, cabbage, and spicy and fried foods were mentioned most often (ranging between 55% and 65%). Response to dietary triggers differed between subtypes and severity groups, but absolute differences were small. Multiple correspondence analysis did not reveal clustering between dietary triggers, and ellipses for the subtypes overlapped. Some clustering was seen when ellipses were drawn for severity, which indicates that severity explained a fraction of the variation in response to dietary triggers, and subtypes did not. The food score was not significantly different between subtypes but was significantly higher with higher levels of severity (mild = 20.9 ± 17, moderate = 29.2 ± 19, severe = 37.9 ± 20, P < .001), having depressive (no = 31.4 ± 20, yes = 37.4 ± 20, P < .001) or anxious symptoms (no = 30.7 ± 20, yes = 35.2 ± 20, P < .001), and lower quality of life (lower quality of life = 38.5 ± 19, higher quality of life = 26.5 ± 19, P < .001).

CONCLUSION

Patients with different IBS subtypes or IBS severity do not identify different self-reported dietary triggers. Patients with more severe IBS and who experience anxiety or depression tend to have severe responses to more dietary triggers. IBS severity seems a better classifier than Rome IV criteria regarding diet. Dietary treatment needs to be individualized under guidance of a dietitian.

Efficacy of a curcumin extract (Curcugen™) on gastrointestinal symptoms and intestinal microbiota in adults with self-reported digestive complaints: a randomised, double-blind, placebo-controlled study

BACKGROUND

There is preliminary evidence to suggest curcumin can alleviate digestive symptoms in adults with self-reported digestive complaints and irritable bowel syndrome. However, in all these trials, curcumin was used as a component of a multi-herbal combination and there were consistent concerns associated with risk of bias in most studies. The goal of this study was to investigate the effects of a curcumin extract (Curcugen™) on gastrointestinal symptoms, mood, and overall quality of life in adults presenting with self-reported digestive complaints. Moreover, to determine the potential therapeutic mechanisms of action associated with curcumin, its effects on intestinal microbiota and small intestinal bowel overgrowth (SIBO) were examined.

METHODS

In this 8-week, parallel-group, double-blind, randomised controlled trial, 79 adults with self-reported digestive complaints were recruited and randomised to receive either a placebo or 500 mg of the curcumin extract, Curcugen™. Outcome measures included the Gastrointestinal Symptom Rating Scale (GSRS), intestinal microbial profile (16S rRNA), Depression, Anxiety, and Stress Scale - 21 (DASS-21), Short Form-36 (SF-36), and SIBO breath test.

RESULTS

Based on self-report data collected from 77 participants, curcumin was associated with a significantly greater reduction in the GSRS total score compared to the placebo. There was also a greater reduction in the DASS-21 anxiety score. No other significant between-group changes in self-report data were identified. An examination of changes in the intestinal microbial profile and SIBO test revealed curcumin had no significant effect on these parameters. Curcumin was well-tolerated with no significant adverse events.

CONCLUSIONS

The curcumin extract, Curcugen™, administered for 8 weeks at a dose of 500 mg once daily was associated with greater improvements in digestive complaints and anxiety levels in adults with self-reported digestive complaints. Compared to the placebo, there were no significant changes in intestinal microbiota or SIBO; however, further research using larger samples and testing methods that allow more detailed microbial analyses will be important. An investigation into other potential mechanisms associated with curcumin's gastrointestinal-relieving effects will also be important such as examining its influence on the intestinal barrier function, inflammation, neurotransmitter activity, and visceral sensitivity.

TRIAL REGISTRATION

Australian New Zealand Clinical Trials Registry, Trial ID. ACTRN12619001236189 . Registered 6 September 2019.

Self-reported bowel symptoms are associated with differences in overall gut microbiota composition and enrichment of Blautia in a population-based cohort

BACKGROUND AND AIM

Altered gut microbiota have been suggested as part of an etiology of irritable bowel syndrome (IBS), but studies have shown contrasting results. Our aim was to examine gut microbiota composition in a large population-based cohort, with respect to presence and severity of bowel symptoms.

METHODS

The study cohort consisted of 1988 participants of the Malmö Offspring Study (mean age 40 years, 53% women). From a questionnaire, 19% reported having bowel symptoms the last 2 weeks and 15% reported having IBS. Bowel symptoms were assessed by a validated set of questions with visual analog scales. Gut microbiota was assessed by 16S rRNA gene sequencing (300 bp*2 in V1-V3 region) from fecal samples. The association between abundance of bacteria at genus level and bowel symptoms was calculated by logistic regression or general linear model, adjusted for false discovery rate (q < 0.05).

RESULTS

Self-reported bowel symptoms (P = 0.003) and IBS (P = 0.031) were associated with difference in overall gut microbiota composition (beta-diversity). Additionally, bowel symptoms and IBS were associated with increased abundance of Blautia, and bowel symptoms also with a genus in the SHA98 order and Butyricimonas. Pain was associated with increased abundance of Fusobacterium. Diarrhea was associated positively with [Prevotella] and Blautia and negatively with a genus in the SHA98 order and a genus in the Christensenellaceae family.

CONCLUSION

Self-reported bowel symptoms are associated with differences in overall gut microbiota composition and abundancy of a few specific bacteria at genus level in a population-based cohort. Diarrhea is the individual symptom with most associations.

Adults living with irritable bowel syndrome (IBS): A qualitative systematic review

OBJECTIVE

To consolidate existing qualitative studies which examined the experiences and needs of adults living with IBS, and to gather a holistic insight for future directions and avenues to support these adults.

METHODS

A qualitative systematic review was conducted and six databases were searched for qualitative studies, beginning from each database's inception to July 2020. The qualitative data were meta-synthesised and thematic analysis was adopted. Any discrepancies that arose were discussed between the reviewers until a consensus was reached throughout the process of data screening, selection, critical appraisal and synthesis.

RESULTS

Seventeen studies with a total of 299 adults diagnosed with IBS were included. Four themes were identified: (1) physical, psychological, and social consequences; (2) impact of IBS on working adults; (3) dealing with IBS; and (4) sources of support and support needs.

CONCLUSION

Future research across geographically diverse locations are needed to gather a thorough perspective of the experiences and needs of adults living with IBS. The development and evaluation of technology-based, trained peer-led volunteers, and interventions that adopt mindfulness, active coping strategies, cognitive behavioural therapy and acceptance, and commitment therapy are needed. Ultimately, the collaboration between the relevant stakeholders is essential for standardised instruments and materials for accurate testing, diagnosis, assessment, treatment and management of IBS.

Smart Data Collection for the Assessment of Treatment Effects in Irritable Bowel Syndrome: Observational Study

BACKGROUND

End-of-day symptom diaries are recommended by drug regulatory authorities to assess treatment response in patients with irritable bowel syndrome. We developed a smartphone app to measure treatment response.

OBJECTIVE

Because the employment of an app to measure treatment response in irritable bowel syndrome is relatively new, we aimed to explore patients' adherence to diary use and characteristics associated with adherence.

METHODS

A smartphone app was developed to serve as a symptom diary. Patients with irritable bowel syndrome (based on Rome IV criteria) were instructed to fill out end-of-day diary questionnaires during an 8-week treatment. Additional online questionnaires assessed demographics, irritable bowel syndrome symptom severity, and psychosocial comorbidities. Adherence rate to the diary was defined as the percentage of days completed out of total days. Adherence to the additional web-based questionnaires was also assessed.

RESULTS

Overall, 189 patients were included (age: mean 34.0 years, SD 13.3 years; female: 147/189, 77.8%; male: 42/189, 22.2%). The mean adherence rate was 87.9% (SD 9.4%). However, adherence to the diary decreased over time (P<.001). No significant association was found between adherence and gender (P=.84), age (P=.22), or education level (lower education level: P=.58, middle education level: P=.46, versus high education level), while higher anxiety scores were associated with lower adherence (P=.03). Adherence to the online questionnaires was also high (>99%). Missing data due to technical issues were limited.

CONCLUSIONS

The use of a smartphone app as a symptom diary to assess treatment response resulted in high patient adherence. The data-collection framework described led to standardized data collection with excellent completeness and can be used for future randomized controlled trials. Due to the slight decrease in adherence to diary use throughout the study, this method might be less suitable for longer trials.

Validity and Reliability of the Antepartum Gastrointestinal Symptom Assessment Instrument

OBJECTIVE

To examine the psychometric properties of the nine-item Antepartum Gastrointestinal Symptom Assessment (AP-GI-SA) instrument.

DESIGN

Single-group prospective design.

SETTING

Urban prenatal clinic serving a diverse population.

PARTICIPANTS

Convenience sample of 45 pregnant women.

METHODS

Participants completed the AP-GI-SA before a scheduled prenatal care appointment. We used Bayesian structural equation modeling to evaluate the construct validity of the scale and assessed known-groups validity. We assessed reliability through maximal reliability coefficient estimate and measured internal consistency with Cronbach's alpha coefficient.

RESULTS

Participants completed the instrument in 2 minutes or less. Construct validity was supported by confirmatory factor analysis (posterior predictive p value = 0.49, gamma-hat = 0.970, and root mean square error of approximation = 0.065), which indicated that the single-factor model is a plausible data-generative model for GI symptoms. The maximal reliability coefficient of 0.75 and Cronbach's alpha coefficient of 0.67 supported reliability. Average AP-GI-SA scores were the highest for women in the third trimester. Of all nine GI symptoms, heartburn in the third trimester received the highest score.

CONCLUSION

Our findings provide preliminary support for the validity and reliability of the AP-GI-SA. The instrument may be used as a measure in intervention studies where GI symptoms of pregnancy are an outcome. The AP-GI-SA could also be useful in clinical settings to quickly evaluate GI symptoms.

Presentation and Characteristics of Abdominal Pain Vary by Irritable Bowel Syndrome Subtype: Results of a Nationwide Population-Based Study

INTRODUCTION

Abdominal pain is a cardinal feature of irritable bowel syndrome (IBS); however, differences in abdominal pain among IBS subtypes remain unknown. We aimed to characterize abdominal pain symptoms among established IBS subtypes using data from the National Gastrointestinal (GI) Survey.

METHODS

Individuals participating in the National GI Survey completed National Institutes of Health GI Patient-Reported Outcomes Measurement Information System (GI-PROMIS) questionnaires. Adults meeting modified Rome III IBS criteria and reporting abdominal pain in the previous 7 days were eligible. Outcomes included abdominal pain severity, bothersomeness, interference with daily activities, frequency, and location. Results were stratified by subtype (diarrhea [IBS-D], constipation [IBS-C], and mixed [IBS-M]). Regression models adjusted for demographics and comorbidities.

RESULTS

One thousand one hundred fifty-eight individuals (245 IBS-D, 232 IBS-C, and 681 IBS-M) with active IBS symptoms (defined as abdominal pain in the past 7 days) were included. Demographics were similar among the subtypes except for age, race/ethnicity, education, and marital status. The GI-PROMIS score was lower for IBS-D (percentile score of 68.6, SD = 25.1; P = 0.001) and IBS-M (69.1, SD = 25.1; P < 0.001) compared with IBS-C (75.5, SD = 20.7). Abdominal pain was more bothersome (P = 0.001), caused more interference with daily activities (P = 0.03), and was more frequent (P = 0.047) for individuals with IBS-C compared with individuals with IBS-D. No differences in these domains were seen between individuals with IBS-D and IBS-M. Individuals with IBS-C and IBS-M had more widespread pain compared with those with IBS-D.

DISCUSSION

In this population-based study, we found that abdominal pain characteristics differ between the IBS subtypes. Namely, individuals with IBS-C experience more bothersome, frequent, and diffuse abdominal pain compared with those with IBS-D.

Gastrointestinal pain

Gastrointestinal (GI) pain - a form of visceral pain - is common in some disorders, such as irritable bowel syndrome, Crohn's disease and pancreatitis. However, identifying the cause of GI pain frequently represents a diagnostic challenge as the clinical presentation is often blurred by concomitant autonomic and somatic symptoms. In addition, GI pain can be nociceptive, neuropathic and associated with cancer, but in many cases multiple aetiologies coexist in an individual patient. Mechanisms of GI pain are complex and include both peripheral and central sensitization and the involvement of the autonomic nervous system, which has a role in generating the symptoms that frequently accompany pain. Treatment of GI pain depends on the precise type of pain and the primary disorder in the patient but can include, for example, pharmacological therapy, cognitive behavioural therapies, invasive surgical procedures, endoscopic procedures and lifestyle alterations. Owing to the major differences between organ involvement, disease mechanisms and individual factors, treatment always needs to be personalized and some data suggest that phenotyping and subsequent individual management of GI pain might be options in the future.

Randomized clinical trial: the effect of probiotic Bacillus coagulans Unique IS2 vs. placebo on the symptoms management of irritable bowel syndrome in adults

The therapeutic effects of B. coagulans Unique IS2 have been well established in children with irritable bowel syndrome (IBS), but its efficacy in adults remain under reported. Thus, in this study the efficacy of B. coagulans Unique IS2 in the management of IBS symptoms in adults was investigated. Patients (n = 153) fulfilling Rome III criteria were provided placebo capsules for a 2 weeks run-in period. Only patients satisfying compliance criteria (n = 136) were randomized (double blind) to receive either B. coagulans Unique IS2 (2 billion CFU) or placebo capsules daily for 8 weeks. Reduction of abdominal discomfort/pain intensity and increase in complete spontaneous bowel movements were analyzed as primary end points. Other clinical symptoms of IBS and serum cytokines were also evaluated. B. coagulans Unique IS2 showed significant improvement in primary and secondary endpoints, as compared to placebo. Haematology of both the arms remained normal. No significant changes in pro- (IL-6, IL-12, TNF-α, INF- γ) and anti-inflammatory cytokine (IL-10) levels were detected at the end of B. coagulans treatment (8 weeks) as compared to placebo. B. coagulans was well tolerated with no severe adverse events to report. Overall, the results demonstrate that B. coagulans Unique IS2 is efficacious in the management of IBS symptoms in adults (18–60 years).

Symptom frequency and development of a generic functional disorder symptom scale suitable for use in studies of patients with irritable bowel syndrome, fibromyalgia syndrome or chronic fatigue syndrome

Objectives

To describe the extent to which irritable bowel syndrome (IBS), fibromyalgia syndrome (FMS), and chronic fatigue syndrome (CFS) exhibit symptom overlap, and to validate a patient-derived, generic symptom questionnaire.

Methods

A patient-derived 61-item symptom-frequency questionnaire was completed by participants recruited through IBS, FMS and CFS self-help websites. Principal axis factor analysis with oblimin rotation was performed separately for those reporting an IBS, FMS or CFS diagnosis.

Results

Questionnaires were completed by 1751 participants of whom 851 reported more than one of the three diagnoses. Stomach pain on at least a weekly basis was reported by 79% of IBS, 52% of FMS, and 43% of CFS single diagnosis participants. Pain increasing the day after activity was reported by 32% of IBS, 94% of FMS, and 85% of CFS single diagnosis participants. Waking still tired at least once weekly was reported by 75% of IBS, 97% of FMS, and 95% of CFS single diagnosis participants. Exploratory factor analysis produced consistent results across all three diagnostic groups, the 61 items loading on 12 correlated factors with a single higher order factor on which all items loaded. Frequency analysis led to the rejection of one item (cold sores on or near lips), and freeform reporting by participants of additional symptoms identified an additional five, namely, restless legs, hair loss/brittle hair/thinning, dizziness/balance problems, blurred vision and urination problems.

Conclusions

IBS, FMS and CFS are polysymptomatic spectrum disorders with a wide range of overlapping symptoms, many of which are unrelated to diagnostic criteria. Frequency analysis and factor analysis confirm the validity of using the same questionnaire across different diagnostic categories. The 65-item general symptom questionnaire (GSQ-65) is a valid generic symptom scale suitable for assessing the many different symptoms of people with IBS, FMS and CFS.

Psychological and Social Factors Associated with Pain in Inflammatory Bowel Disease: A Systematic Literature Review of the Evidence in Adult and Pediatric Studies

Background

Pain is commonly experienced in both active and dormant inflammatory bowel disease (IBD). Psychological and social factors, which can be key to pain experience, have been relatively neglected; the only prior comprehensive review focused solely on studies of adults. The present review, therefore, sought to systematically examine relationships between pediatric and adult experience of pain and psychosocial variables.

Method

Systematic searches of 5 databases were conducted to identify studies including measures of pain and psychosocial variables, in pediatric or adult IBD populations. Quality appraisal of studies was undertaken using a qualified assessment tool.

Results

Twenty-three articles met the inclusion criteria. Ten examined relationships between pain and psychosocial variables in adults, and 13 examined in pediatric populations. Inverse relationships were identified between pain and quality of life (QOL) in both populations, with potential differences in pain localization between the two populations. Psychological distress, notably depression, was also important in both populations, with inconsistent evidence for a role for anxiety in pediatric samples. Specific coping styles, and familial responses to communications, also appeared relevant, but with weaker evidence. There was substantial heterogeneity in measures, statistical analyses and sample characteristics, and quality appraisal revealed methodological weaknesses.

Conclusions

Significant relationships were found between pain and various psychological indices, notably QOL and depression. However, most studies were underpowered, did not sufficiently control for key confounds, and almost exclusively reported on Western participants. Adequately powered, statistically sound studies encompassing diverse populations are required to further clarify relationships between pain and psychosocial variables in IBD.

Anhedonia in irritable bowel syndrome and in inflammatory bowel diseases and its relationship with abdominal pain

BACKGROUND

Anhedonia is the lowered ability to experience pleasure from rewarding or enjoyable activities and is considered a symptom of depression. Inflammatory bowel disease (IBD) and irritable bowel syndrome (IBS) are frequently accompanied by psychiatric disorders such as depression. However, to our knowledge, studies have yet to investigate the anhedonia in these patients. Our aim was to study the level of anhedonia in patients with IBD and IBS in comparison with healthy controls (HC), and to relate anhedonia levels with the severity of abdominal pain.

METHODS

We consecutively recruited IBD and IBS patients. All patients fulfilled the Snaith-Hamilton Pleasure Scale (SHAPS), a self-rating scale consisting of 14 items that cover the domains of social interaction, food, and drink, sensory experiences, achievement and pastimes, and the Beck Depression Inventory-II (BDI-II) to screen for depression. Moreover, we calculated abdominal pain on a (0-100) Visual Analog Scale (VAS) in all patients.

KEY RESULTS

We enrolled 120 patients (64 IBD and 56 IBS) and 81 HC. Among IBD patients, 34 had Crohn's disease and 30 ulcerative colitis. All patients as a whole had significantly higher SHAPS and BDI-II scores than HC (1.3 ± 1.5 vs 0.8 ± 0.1; P = 0.01 and 10.4 ± 7.5 vs 5.9 ± 4.9; P < 0.001, respectively), while no significant differences were found among groups. SHAPS score showed a significant correlation in only a few statements of BDI-II. In our cohort, a multivariate regression analysis showed that SHAPS score was significantly related to current abdominal pain (0-100 VAS) (P = 0.03) independent of gender and age.

CONCLUSIONS AND INFERENCES

The level of anhedonia was higher in all patients compared to healthy controls. The more the subject is anhedonic, the higher the VAS scale for abdominal pain. This study suggests that anhedonia would need to be very carefully weighed in IBD and IBS patients.

The Experience Sampling Method-Evaluation of treatment effect of escitalopram in IBS with comorbid panic disorder

BACKGROUND

Confirming treatment response in clinical trials for irritable bowel syndrome (IBS) is challenging, due to the lack of biomarkers and limitations of the currently available symptom assessment tools. The Experience Sampling Method (ESM) might overcome these limitations by collecting digital assessments randomly and repeatedly during daily life. This study evaluated differences in change in abdominal pain between real-time (ie, ESM) and retrospective (ie, Gastrointestinal Symptom Rating Scale [GSRS] and an end-of-day symptom diary) measurements, using data of an RCT on escitalopram vs placebo in patients with IBS and comorbid panic disorder.

METHODS

Twenty-nine IBS patients with comorbid panic disorder were included in a 6-month RCT. The GSRS, diary, and ESM were completed at baseline (t = 0) and after 3 (t = 3) and 6 months (t = 6). Linear mixed models were used.

KEY RESULTS

Experience Sampling Method analyses revealed a significant interaction between escitalopram and time, and ESM abdominal pain scores were 1.4 points lower in the escitalopram group compared to placebo at t = 6 (on a 1-to-7 scale; P = 0.021). When including the interaction with momentary anxiety, the reduction in abdominal pain scores in escitalopram vs placebo was even more pronounced for higher levels of anxiety. Average GSRS- and end-of-day abdominal pain scores were not significantly different between escitalopram and placebo at t = 3 and 6.

CONCLUSIONS & INFERENCES

Real-time ESM has the potential to capture treatment response more sensitively compared to a retrospective end-of-day GI symptom diary and the GSRS, by taking into account day-to-day symptom variability as well as momentary factors that might moderate treatment effect, such as anxiety.

Intestinal Microbiome in Irritable Bowel Syndrome before and after Gut-Directed Hypnotherapy

Irritable bowel syndrome (IBS) is a disorder with brain-gut-microbiome alterations. Gut-directed hypnotherapy (GHT) has been shown to improve quality of life and symptoms in IBS. This therapy targets psychological coping, central nervous processing and brain-gut interaction. Studies have also demonstrated effects of hypnosis on intestinal transit and the mucosal immune system. So far, no study has examined the effect of GHT on the intestinal microbiome. This study aimed at examining microbial composition, IBS symptoms, and psychological distress before and after GHT. Methods: Fecal samples were collected from 38 IBS patients (Rome-III criteria, mean age 44 years, 27 female, 11 male, 22 diarrhea-dominant, 12 alternating-type and 4 constipation-dominant IBS) before and after 10 weekly group sessions of GHT. Assessments in psychological (perceived stress, PSQ; psychological distress, HADS-D; quality of life, visual analogue scales) and IBS symptom-related variables (IBS severity, IBS-SSS; single symptoms, visual analogue scales) were performed with validated questionnaires. Fecal samples underwent microbial 16S rRNA analyses (regions V1–2). Results: Microbial alpha diversity was stable before and after GHT (chao1 2591 ± 548 vs. 2581 ± 539, p = 0.92). No significant differences were found in relative bacterial abundances but trends of reduced abundance of Lachnospiraceae 32.18 (4.14–39.89) Median (Q1–Q3) vs. 28.11 (22.85; 35.55) and Firmicutes: Bacteroidetes ratio after GHT were observable. Significant reductions in symptom severity (323 (266–371) vs. 264 (191–331), p = 0.001) and psychological distress 17.0 (12.6–21.8) vs. 12.0 (8.3–18.0), p = 0.001, and increased well-being were found after GHT. Adequate relief after therapy was reported by 32 (84%) patients. Conclusion: Reductions in IBS symptoms and psychological burden were observed after gut-directed hypnotherapy, but only small changes were found in intestinal microbiota composition. The findings suggest that hypnosis may act by central nervous impact and other factors largely independent from microbiota composition modulating the brain-gut axis, possibly alterations in vagus nerve functioning and microbiota metabolism.

Effect of electroacupuncture at homotopic and heterotopic acupoints on abdominal pain in patients with irritable bowel syndrome: study protocol for a randomized controlled trial

BACKGROUND

Acupuncture has been widely applied in the clinic to treat irritable bowel syndrome (IBS), but the underlying mechanism remains unknown. Diffuse noxious inhibitory control (DNIC) is deficient in patients with IBS, which attenuates the systemic analgesic effect elicited by noxious stimulation that is remote from pain areas. Therefore, the aim of this study is to investigate the analgesic effect of electroacupuncture (EA) at homotopic or heterotopic acupoints on abdominal pain in patients with IBS.

METHODS/DESIGN

This study is a randomized, single-blinded, controlled, four-arm parallel trial. A total of 144 patients will be randomly assigned to four groups: a homotopic noxious stimulation group (group A), a homotopic innocuous stimulation group (group B), a heterotopic noxious stimulation group (group C), and a heterotopic innocuous stimulation group (group D). Each patient will receive 14 sessions of treatment, twice per week for 7 weeks. The primary outcome will be pain intensity measured with the visual analog scale. The secondary outcomes will include the IBS Symptom Severity Scale, IBS Quality of Life questionnaire, pain threshold (PT), and the Symptom Checklist-90 for psychological distress. The PT will be measured before and after every treatment. All other outcomes will be evaluated before the 1st treatment, after 7th and 14th treatment, and 3 months later during follow-up.

DISCUSSION

The aim of this study is to assess the analgesic effect of EA at homotopic (abdomen) acupoints and heterotopic (lower limb) acupoints on abdominal pain in patients with IBS, as well as the difference in analgesic effects between noxious and innocuous stimulation.

TRIAL REGISTRATION

Chinese Clinical Trial Registry, ChiCTR-IPR-15006879 . Registered on 5 August 2015.

A Microbial Signature of Psychological Distress in Irritable Bowel Syndrome

OBJECTIVE

Irritable bowel syndrome (IBS) is associated with alterations along the brain-gut-microbiota axis. Previous studies have suggested a parallel segregation of microbial features and psychological burden in IBS. This study aimed at exploring the microbial correlates of psychological distress in patients with IBS.

METHODS

Forty-eight patients with IBS (Rome III criteria, M (SD) age = 42 (15) years, 35 female, 25 diarrhea-dominant, 5 constipation-dominant, and 18 alternating-type IBS) were assessed for psychological and clinical variables with validated questionnaires, fecal samples underwent microbial 16S rRNA analyses (regions V1-2). Microbial analyses comprised examination of alpha and beta diversity, correlational analyses of bacterial abundance and comparisons among subgroups defined by thresholds of psychological and IBS symptom variables, and machine learning to identify bacterial patterns corresponding with psychological distress.

RESULTS

Thirty-one patients (65%) showed elevated psychological distress, 22 (31%) anxiety, and 10 depression (21%). Microbial beta diversity was significantly associated with distress and depression (q = .036 each, q values are p values false discovery rate-corrected for multiple testing). Depression was negatively associated with Lachnospiraceae abundance (Spearman's ρ = -0.58, q = .018). Patients exceeding thresholds of distress, anxiety, depression, and stress perception showed significantly higher abundances of Proteobacteria (q = .020-.036). Patients with anxiety were characterized by elevated Bacteroidaceae (q = .036). A signature of 148 unclassified species accounting for 3.9% of total bacterial abundance co-varied systematically with the presence of psychological distress.

CONCLUSIONS

Psychological variables significantly segregated gut microbial features, underscoring the role of brain-gut-microbiota interaction in IBS. A microbial signature corresponding with psychological distress was identified.

CLINICAL TRIAL REGISTRATION

ClinicalTrials.gov identifier NCT02536131, retrospectively registered.

Painful or Mild-Pain Constipation? A Clinically Useful Alternative to Classification as Irritable Bowel Syndrome with Constipation Versus Functional Constipation

PURPOSE

Abdominal pain is not used to characterize constipated patients. This study aimed to compare clinical, psychological, and physiological features in patients with IBS-constipation (IBS-C) with those in patients with functional constipation (FC) according to the intensity of abdominal pain.

METHODS

All patients filled a standard Rome III questionnaire. In addition, they indicated the intensity of constipation, diarrhea, bloating, and abdominal pain on a 10-point Likert scale, and their stool form with the Bristol Stool Form Scale. Anxiety and depression were assessed with the Beck Depression Inventory and the State-Trait Anxiety Inventory. Physiological evaluation included anorectal manometry and total and segmental colonic transit time.

MAIN RESULTS

A total of 546 consecutive patients, 245 with IBS-C and 301 with FC, were included. Painful constipation (PFC) was found by cluster analysis and subsequently defined as having a value over four on the Likert scale for abdominal pain. PFC was found in 67% of IBS-C patients and in 22% of FC patients. PFC patients have digestive disorders with greater frequency and report higher levels of constipation and bloating, despite similar stool form. They have higher scores of depression, state and trait anxiety, and shorter terminal transit time than mild-pain constipated patients. Compared to IBS-C patients, PFC patients report higher levels of abdominal pain (P < 0.001). Psychological and physiological parameters were similar in PFC and IBS-C patients.

CONCLUSION

Painful constipation and mild-pain constipation could be an alternative way to identify constipated patients than using the diagnosis of IBS-C and FC for clinical evaluation and drug studies.

Laparoscopic Adhesiolysis in Chronic Abdominal Pain: 15-Year Follow-up Study

BACKGROUND/GOAL

Intra-abdominal adhesions are probably underdiagnosed cause for chronic abdominal pain. Our aim was to evaluate late (>10 y) effect of laparoscopic adhesiolysis on chronic abdominal pain.

STUDY

This was a nonrandomized follow-up study of 68 patients (9 males, 59 females) who suffered chronic abdominal pain. The index operation (laparoscopy and adhesiolysis; n=72 patients) was performed during 1997 to 2001. A quality-of-life questionnaire was asked after the mean follow-up time of 15 years. The hospital records of patients, reoperations for chronic abdominal pain, and full medical history were also reviewed.

RESULTS

Patients reported that adhesion-related pain was abolished or diminished in 90% during 15-year follow-up, but still 28 (41%) complained about some abdominal symptom. One third of the patients used pain-relieving medication or proton-pump inhibitors to relieve their symptoms. Furthermore, 46 (68%) patients had contacted medical service for reexamination of abdominal discomfort and 16 (24%) were reoperated because of some abdominal disease. When the patients with dense adhesions versus no or minimal adhesions were compared in the long term, no difference in the response of pain was noticed after 15 years of adhesiolysis.

CONCLUSIONS

In carefully selected patients suffering from chronic abdominal pain, the positive effect of laparoscopic adhesiolysis stands beyond 15 years after the surgery. Although the patients reported relief of pain they still had various abdominal symptoms.

Development, content validity, and cross-cultural adaptation of a patient-reported outcome measure for real-time symptom assessment in irritable bowel syndrome

BACKGROUND

End-of-day questionnaires, which are considered the gold standard for assessing abdominal pain and other gastrointestinal (GI) symptoms in irritable bowel syndrome (IBS), are influenced by recall and ecological bias. The experience sampling method (ESM) is characterized by random and repeated assessments in the natural state and environment of a subject, and herewith overcomes these limitations. This report describes the development of a patient-reported outcome measure (PROM) based on the ESM principle, taking into account content validity and cross-cultural adaptation.

METHODS

Focus group interviews with IBS patients and expert meetings with international experts in the fields of neurogastroenterology & motility and pain were performed in order to select the items for the PROM. Forward-and-back translation and cognitive interviews were performed to adapt the instrument for the use in different countries and to assure on patients' understanding with the final items.

KEY RESULTS

Focus group interviews revealed 42 items, categorized into five domains: physical status, defecation, mood and psychological factors, context and environment, and nutrition and drug use. Experts reduced the number of items to 32 and cognitive interviewing after translation resulted in a few slight adjustments regarding linguistic issues, but not regarding content of the items.

CONCLUSIONS AND INFERENCES

An ESM-based PROM, suitable for momentary assessment of IBS symptom patterns was developed, taking into account content validity and cross-cultural adaptation. This PROM will be implemented in a specifically designed smartphone application and further validation in a multicenter setting will follow.

Habitual diet and diet quality in Irritable Bowel Syndrome: A case-control study

BACKGROUND

Diet is considered to be a key factor in symptom generation in Irritable Bowel Syndrome (IBS) and patients tend to exclude food products from their diet in pursue of symptom relief, which may impair diet quality.

METHODS

We evaluated habitual dietary intake in IBS patients with regard to nutrients and food products using an extensive food frequency questionnaire. One hundred ninety-four IBS patients were compared to 186 healthy controls using multiple logistic regression analysis. An overall diet quality score was calculated for each participant based on the criteria of the Dutch Healthy Diet (DHD) index.

KEY RESULTS

A lower DHD-score was found for IBS (mean [SD]: 52.9 [9.6]) vs controls (55.1 [9.2], P=.02). The diet of patients was lower in fibers (21 g vs 25 g per day, P=.002) and fructose (14 g vs 16 g, P=.033), while higher in total fat (37% vs 36% of total energy intake, P=.010) and added sugars (46 g vs 44 g, P=.029). Differences in daily intake of food products included lower consumption of apples (40 g vs 69 g, P<.001), pasta (28 vs 37 g, P=.029) and alcoholic beverages (130 g vs 193 g, P=.024) and higher consumption of processed meat (38 g vs 29 g, P<.001). Some of these findings correlated with gastrointestinal symptoms, showing differences between IBS subtypes.

CONCLUSIONS AND INFERENCES

Differences in habitual diet were described, showing lower diet quality in IBS patients compared to controls, with increased consumption of fat and lower intake of fibers and fructose. Our data support the importance of personalized and professional nutritional guidance of IBS patients.

Biomarkers for visceral hypersensitivity in patients with irritable bowel syndrome

BACKGROUND

Increased visceral sensitivity is observed in up to 60% of patients with Irritable Bowel Syndrome (IBS). Mucosal inflammation, altered neuroendocrine activity and intraluminal metabolic processes may contribute to the development of visceral hypersensitivity. Previously, we demonstrated that biomarkers, indicative for these biological processes, were altered in IBS patients compared to healthy controls. However, how these processes relate to visceral hypersensitivity is unknown.

AIM

The aim of this study was to provide insight in biological processes associated with visceral hypersensitivity. Fecal and plasma biomarkers were measured in normosensitive and hypersensitive IBS patients.

METHODS

A total of 167 IBS patients underwent a rectal barostat procedure to assess visceral sensitivity to pain. Based on the outcome, patients were classified into a normosensitive or hypersensitive group. Calprotectin, human β-defensin 2 (HBD2), chromogranin A (CgA), and short chain fatty acids (SCFAs) were measured in feces, citrulline in plasma, and serotonin and its main metabolite 5-hydroxyindoleacetic acid (5-HIAA) in platelet-poor plasma.

KEY RESULTS

Fecal markers and plasma citrulline were measured in 83 hypersensitive and 84 normosensitive patients, while platelet-poor plasma for the assessment of serotonin and 5-HIAA was available for a subgroup, i.e. 53 hypersensitive and 42 normosensitive patients. No statistically significant differences were found in concentrations of biomarkers between groups. Adjustment of the analyses for potential confounders, such as medication use, did not alter this conclusion.

CONCLUSIONS & INFERENCES

Our findings do not support a role for the biological processes as ascertained by biomarkers in visceral hypersensitivity in IBS patients. This study is registered in the US National Library of Medicine (clinicaltrials.gov, NCT00775060).

Factors Associated with Severity of Irritable Bowel Syndrome Symptoms in Patients with Endometriosis

OBJECTIVE

This study sought to examine factors associated with severity of irritable bowel syndrome (IBS) by using the Birmingham IBS symptom scale in patients presenting with endometriosis to a tertiary referral centre.

METHODS

A prospective research cohort of patients presenting to a tertiary referral centre for endometriosis was evaluated for the presence and severity of IBS between December 2013 and April 2015. Patients with endometriosis had a diagnosis of IBS by using the Rome III criteria and were evaluated for severity of IBS symptoms by using the Birmingham IBS symptom scale. Multifactorial variables, including stage of endometriosis at the time of previous surgery, clinical examination findings, mood disorder questionnaire scores, and lifestyle factors, were evaluated using the t test and Spearman rank correlation test.

RESULTS

A total of 194 of 373 (52%) women with confirmed endometriosis had a diagnosis of IBS. Factors associated with severity of IBS symptoms in patients with endometriosis included lower-stage endometriosis (P = 0.004), presence of mood disorders (P <0.001), tenderness on physical examination (P ≤ 0.001), a history of sexual assault (P ≤ 0.02), and presence of sleep disturbance (P ≤ 0.01). Evaluation of the subscales of the Birmingham IBS symptom scale revealed a strong association between the previously identified factors and the pain subscale.

CONCLUSION

Using the Birmingham IBS symptom scale, our study revealed more severe IBS symptoms in patients with lower-stage endometriosis and identified other variables highly associated with severity of IBS. Continued research is required to characterize further the clinical importance of IBS symptoms in patients with endometriosis-associated pelvic pain.

Functional urological disorders: a sensitized defence response in the bladder-gut-brain axis

Functional urological and gastrointestinal disorders are interrelated and characterized by a chronic course and considerable treatment resistance. Urological disorders associated with a sizeable functional effect include overactive bladder (OAB), interstitial cystitis/bladder pain syndrome (IC/BPS), and chronic prostatitis/chronic pelvic pain syndrome (CP/CPPS). Poor treatment outcomes might be attributable to untreated underlying psychological and psychiatric disorders, as the co-occurrence of functional urological and gastrointestinal disorders with mood and anxiety disorders is common. The hypothetical bladder-gut-brain axis (BGBA) is a useful framework under which this interaction can be studied, suggesting that functional disorders represent a sensitized response to earlier threats such as childhood adversity or previous traumatic events, resulting in perceived emotional and bodily distress - the symptoms of functional disorders. Psychological and physical stress pathways might contribute to such alarm falsification, and neuroticism could be a risk factor for the co-occurrence of functional disorders and affective conditions. Additionally, physical threat - either from external sources or internal sources such as infection - might contribute to alarm falsification by influencing body-brain crosstalk on homeostasis and, therefore, affecting mood, cognition, and behaviour. Multidisciplinary research and an integrated care approach is, therefore, required to further elucidate and remediate functional urological and gastrointestinal polymorphic phenotypes.

A novel biomarker panel for irritable bowel syndrome and the application in the general population

Biological markers that measure gut health and diagnose functional gastro-intestinal (GI) disorders, such as irritable bowel syndrome (IBS), are lacking. The objective was to identify and validate a biomarker panel associated with the pathophysiology of IBS that discriminates IBS from healthy controls (HC), and correlates with GI symptom severity. In a case-control design, various plasma and fecal markers were measured in a cohort of 196 clinical IBS patients and 160 HC without GI symptoms. A combination of biomarkers, which best discriminates between IBS and HC was identified and validated in an independent internal validation set and by permutation testing. The correlation between the biomarker panel and GI symptom severity was tested in IBS patients and in a general population cohort of 958 subjects. A set of 8 biomarker panel was identified to discriminate IBS from HC with high sensitivity (88.1%) and specificity (86.5%). The results for the IBS subtypes were comparable. Moreover, a moderate correlation was found between the biomarker panel and GI symptom scores in the IBS (r = 0.59, p < 0.001) and the general population cohorts (r = 0.51, p = 0.003). A novel multi-domain biomarker panel has been identified and validated, which correlated moderately to GI symptom severity in IBS and general population subjects.