Abdominal bloating is the most bothersome symptom in irritable bowel syndrome with constipation (IBS-C): a large population-based Internet survey in Japan

Structural equation models of health behaviour, psychological well-being, symptom severity and quality of life in abdominal bloating

Background

The objective of this study was to investigate the inter-relationship between psychosocial variables and their impact on symptom severity and quality of life (QoL) concerning abdominal bloating.

Methods

The study adopted a cross-sectional design with purposive sampling. Participants who consented and met the criteria for bloating based on the Rome IV classification completed designated questionnaires. Independent variables comprised health beliefs, intentions, health-promoting behaviors, social support, depression, and anxiety, while dependent variables included bloating severity (general and within 24 h) and QoL. Structural Equation Modeling (SEM) was conducted utilizing Mplus 8.0 to analyze the relationships between these factors.

Results

A total of 323 participants, with a mean age of 27.69 years (SD = 11.50), predominantly females (64.7%), volunteered to participate in the study. The final SEM model exhibited good fit based on various indices (CFI = 0.922, SRMR = 0.064, RMSEA (95% CI) = 0.048 (0.041-0.054), p-value = 0.714), with 15 significant path relationships identified. The model explained 12.0% of the variance in severity within 24 h, 6% in general severity, and 53.8% in QoL.

Conclusion

The findings underscore the significant influence of health beliefs, intentions, behaviors, social support, depression, and anxiety on symptom severity and QoL in individuals experiencing abdominal bloating.

Relationship Between Colonic Transit Response to Eating With Self-reported Constipation Severity in Constipated Patients According to the Phenotype

Background/Aims

Eating is the major synchronizer of gastrointestinal motility and secretions. The present study aims to evaluate the interplay between self-perceived constipation severity (CS) and colonic response to eating in constipated patients according to the phenotype.

Methods

We included 387 consecutive outpatients complaining of Rome IV chronic idiopathic constipation. Likert scales for CS, abdominal pain severity, bloating severity, depression and anxiety assessment, total and segmental colonic transit time (CTT), and colonic transit response to eating (CTRE) were performed in all patients.

Results

Of the 387 patients included (49.7 ± 16.4 years), 320 (83%) were female, 203 had irritable bowel syndrome with constipation (IBS-C), 184 as functional constipation (FC), and 283 had defecation disorders (DD). The female gender was characterized by increased bloating severity (P = 0.011) and decreased Bristol stool form (P = 0.002). In IBS-C and FC patients, CS was related with bloating severity (P < 0.001 in both groups) and total CTT (P = 0.007 in IBS-constipation, P = 0.040 in FC). In IBS-C patients, CS was also associated with abdominal pain severity (P = 0.003) and Bristol stool form (P = 0.004). In contrast, in FC, CS was only related to left CTRE (P = 0.006), and in patients with DD, CS was associated with total CTT (P < 0.001) and left CTRE (P = 0.002).

Conclusion

Colonic transit response to eating was not associated to CS in IBS-C patients, but left CTRE was associated with constipation severity in FC and DD patients.

Cognition of abdominal pain and abdominal discomfort in Chinese patients with irritable bowel syndrome with diarrhea

BACKGROUND

In Asia, the proportion of patients with irritable bowel syndrome (IBS) with abdominal discomfort alone is significantly higher than that in western countries. The purposes of this study are to understand the cognition of abdominal pain and abdominal discomfort in Chinese patients with IBS and to compare the clinical characteristics of patients with abdominal pain alone and with abdominal discomfort alone.

METHODS

Patients with IBS with diarrhea (IBS-D) who met the Rome III diagnostic criteria and had episodes of at least one day/week were consecutively enrolled. The cognition of abdominal pain and abdominal discomfort were investigated through face-to-face unstructured interview. Patients were divided into a pain group and a discomfort group according to the cognition interviews, then the characteristics and severity of symptoms (IBS symptom severity scale, IBS-SSS), IBS quality of life (IBS-QOL) and psychological state were compared between groups.

RESULTS

A total of 88 patients with IBS-D were enrolled. Most of the patients with self-reported abdominal pain described their pain as spasm/cramping; patients with self-reported abdominal discomfort had as many as 24 different descriptions of discomfort. Most patients having abdominal pain and discomfort could accurately distinguish the two symptoms. The degree of abdominal pain in the pain group was higher than abdominal discomfort in the discomfort group (P = 0.002). There was no significant difference in IBS-SSS, extra-intestinal pain, IBS-QOL, and psychological state between the two groups.

CONCLUSIONS

For Chinese patients with IBS-D, abdominal pain and abdominal discomfort are two different symptoms, but they have similar clinical features.

TRIAL REGISTRATION

ChiCTR, ChiCTR1900028082. Registered 11 December 2019 - Retrospectively registered, http://www.chictr.org.cn .

Clinical efficacy of one-finger meditation massage on IBS-C based on the "gut-brain axis" theory: study protocol for a randomized controlled trial

BACKGROUND

As a common disorder of the gastrointestinal tract, irritable bowel syndrome (IBS) can have negative effects on patients and society, with irritable bowel syndrome with constipation(IBS-C) accounting for a large proportion of these effects. The main clinical manifestations of IBS-C are constipation, abdominal pain, and abdominal distension, which seriously impact the quality of life of patients. The mechanisms of IBS are complex, and the gut-brain axis has been an emerging and recognized theoretical system in recent years. Based on the theory of the gut-brain axis and the theory of Chinese medicine, we designed this study to evaluate the efficacy of one-finger meditation massage in treating IBS-C.

METHODS/DESIGN

This is a randomized controlled trial. Eligible patients with irritable bowel syndrome (IBS-C) wererandomized 1:1 to a test group (massage plus probiotics) and a control group (probiotics). Patients in the test group weretreated once every 10 days for three consecutive courses of treatment (i.e., three months) and weregiven Bifidobacterium trifolium capsules 630 mg/dose three times daily 30 min after meals every day during the treatment period, with follow-up observations at the end of the third and sixth months of the treatment period. The control group weregiven Bifidobacterium trifolium capsules 630 mg/dose, 3 times a day for 3 months, with follow-up observations at the end of the third and sixth months of the treatment period. The primary outcome indicators are the concentrations of 5-HT and substance P and the IBS Severity Scale (IBS-SSS) assessment. Secondary outcomes are the Bristol Rating Scale (BRSA) score, the IBS Quality of Life Questionnaire (IBS-QOL scale) score, and the assessment of the effectiveness of the evidence. The results wereassessed at the pretreatment, posttreatment, and follow-up stages. Any side effects weresubject to assessment.

DISCUSSION

The aim of this trial is to provide a new method of treatment based on pharmacological treatment that is easy to use, easy to promote and has proven efficacy and to establish the efficacy and safety of treating IBS-C through this trial.

REGISTRATION FOR TRIAL

Chinese Clinical Trial Registry ChiCTR2200066417 on 5 December 2022. https://www.chictr.org.cn/bin/project/edit?pid=183461.

Characteristics of disorders of gut-brain interaction in the Japanese population in the Rome Foundation Global Epidemiological Study

BACKGROUND

The aims were to use Japanese data from the Rome Foundation Global Epidemiological Study (RFGES) to test the hypotheses that severity of gastrointestinal (GI) symptoms and psychosocial disturbance are ordered as Rome IV irritable bowel syndrome (IBS) > Rome III IBS > DGBI, not IBS > others.

METHODS

Subjects were 2504 Japanese in the RFGES. We assessed DGBI/IBS diagnoses with Rome IV/III, IBS Symptom Severity Scale (IBS-SSS), Patient Health Questionnaire (PHQ) for anxiety/depression and non-GI somatic symptoms, PROMIS-10 for quality of life (QOL), Work Productivity and Activity Impairment (WPAI) Questionnaire, parts of Self-reported IBS Questionnaire (SIBSQ) for meal effect and stress effect, Food Frequency Questionnaire, and medication questions.

KEY RESULTS

The prevalence of Rome IV DGBI was as follows; IBS-C 0.5%, IBS-D 0.8%, IBS-M 0.8%, IBS-U 0.1%, unspecified functional bowel disorder 10.7%, postprandial distress syndrome 2.2%, and epigastric pain syndrome 0.3%. Rome III IBS prevalence; IBS-C 3.0%, IBS-D 3.1%, IBS-M 2.7%, and IBS-U 0.6%. Comparison among Rome IV IBS (n = 54), Rome III IBS (n = 197), other DGBI (n = 746), others (n = 1389) revealed significant order as Rome IV IBS > Rome III IBS > other DGBI > others in IBS-SSS, anxiety/depression, activity impairment, non-GI symptoms, physical QOL, mental QOL, exacerbated symptoms by meals and perceived stress (all p < 0.001).

CONCLUSIONS & INFERENCES

These findings support the study hypotheses. Data from Japan as a culturally homogenous country suggest Rome IV IBS is more severe and hence has more gut-brain psychobehavioral involvement than Rome III IBS.

A Tritordeum-Based Diet for Female Patients with Diarrhea-Predominant Irritable Bowel Syndrome: Effects on Abdominal Bloating and Psychological Symptoms

Most female patients with irritable bowel syndrome (IBS) complain of abdominal bloating rather than abdominal pain and diarrhea. The higher incidence in women could be due to the so-called dysfunctional gas handling. Since diet seems the most effective and durable strategy for managing IBS symptoms, we aimed to evaluate the effects of a 12 week diet based on a relatively new cereal, Tritordeum (TBD), on gastrointestinal (GI) symptoms, anthropometric and bioelectrical impedance parameters, and psychological profiles in 18 diarrhea-predominant IBS (IBS-D) female patients with abdominal bloating as the dominant symptom. The IBS Severity Scoring System (IBS-SSS), the Symptom Checklist-90 Revised, the Italian version of the 36-Item Short-Form Health Survey, and the IBS-Quality of Life questionnaire were administered. The TBD reduces the IBS-SSS “Intensity of abdominal bloating” with a concomitant improvement in the anthropometric profile. No correlation was found between “Intensity of abdominal bloating” and “Abdominal circumference”. Anxiety, depression, somatization, interpersonal sensitivity, and phobic and avoidance manifestations were significantly reduced after TBD. Lastly, anxiety was correlated with “Intensity of abdominal bloating”. Overall, these results suggest the possibility of lowering abdominal bloating and improving the psychological profile of female IBS-D patients using a diet based on an alternative grain such as Tritordeum.

Evaluation and comparison of therapeutic effects of probiotics and colloidal bismuth subcitrate on abdominal bloating

Background

Functional abdominal bloating is one of the functional gastrointestinal disorders (FGIDs). Here, we aimed to investigate and compare the effects of probiotics and colloidal bismuth subcitrate on abdominal bloating.

Methods

This was a double-blinded randomized clinical trial performed on 125 patients with functional abdominal bloating in Isfahan in 2020-2021. At the beginning of the study, information on the frequency of abdominal bloating, its severity, the occurrence of early satiety, frequency of borborygmus, frequency of belching, and the frequency of defecation per week was collected. Patients were divided into 3 groups receiving familact probiotic pills that contained 7 bacterial strains, colloidal bismuth subcitrate tablets, and placebo pills for 4 weeks. Afterwards, the frequency and severity of abdominal bloating and other symptoms were compared.

Results

After 2 weeks, patients in the probiotic group had a significantly lower frequency of abdominal bloating compared to other groups (P= 0.006). After 4 and 8 weeks, patients in the probiotic group and bismuth group had a lower frequency of bloating )3.18±3.02, 4.11±3.34) compared to placebo (5.10±3.54) (P= 0.001 and P= 0.037, respectively). During the study, patients in the probiotic group had a significantly lower bloating severity (41.90% had no symptom) compared to bismuth and placebo groups (12.50 ,12.00% had no symptom) (p< 0.05). The frequency of borborygmus was significantly lower in the probiotic group after 2 and 4 weeks during the study compared to other groups (1.62±0.2 Vs 2.69±0.3, 2.45±0.3 ) (P= 0.010 and P= 0.013, respectively).

Conclusion

According to our data, consumption of probiotics improves the frequency and severity of abdominal bloating and reduces borborygmus. Colloidal bismuth subcitrate also has significant effects.

A Discussion of Whether Various Lifestyle Changes can Alleviate the Symptoms of Irritable Bowel Syndrome

Irritable bowel syndrome (IBS) causes abdominal pain during bowel movements and is diagnosed according to the Rome IV international diagnostic criteria. Patients diagnosed as having IBS experience abdominal pain at least 1 day/week, on average, over a 3-month period and not 3 days per month. A diagnosis of IBS is confirmed if symptoms have persisted for more than 6 months. IBS symptoms negatively affect daily life. First, improving daily habits are important to ameliorating IBS symptoms. IBS symptoms can be alleviated by staying active, sleeping, resting and staying stress-free. In addition, it is important to eat three, balanced meals a day on a regular basis and avoid overeating, especially at night. Spicy foods, high-fat foods, and alcohol can exacerbate symptoms. Researchers found, in a literature review, that IBS symptoms can be ameliorated by improving daily habits, thus relieving abdominal pain and the defecation symptoms of IBS.

Are bowel symptoms and psychosocial features different in irritable bowel syndrome patients with abdominal discomfort compared to abdominal pain?

BACKGROUND

The Rome IV criteria eliminated abdominal discomfort for irritable bowel syndrome (IBS), which was previously included in Rome III. There are questions as to whether IBS patients with abdominal discomfort (seen in Rome III but not Rome IV) are different from those with abdominal pain (Rome IV).

AIM

To compare bowel symptoms and psychosocial features in IBS patients diagnosed with Rome III criteria with abdominal discomfort, abdominal pain, and pain & discomfort.

METHODS

We studied IBS patients meeting Rome III criteria. We administered the IBS symptom questionnaire, psychological status, and IBS quality of life. Patients were classified according to the predominant abdominal symptom associated with defecation into an only pain group, only discomfort group, and pain & discomfort group. We compared bowel symptoms, extraintestinal symptoms, IBS quality of life, psychological status and healthcare-seeking behaviors, and efficacy among the three groups. Finally, we tested risk factors for symptom reporting in IBS patients.

RESULTS

Of the 367 Rome III IBS patients enrolled, 33.8% (124 cases) failed to meet Rome IV criteria for an IBS diagnosis. There were no meaningful differences between the pain group (n = 233) and the discomfort group (n = 83) for the following: (1) Frequency of defecatory abdominal pain or discomfort; (2) Bowel habits; (3) Coexisting extragastrointestinal pain; (4) Comorbid anxiety and depression; and (5) IBS quality of life scores except more patients in the discomfort group reported mild symptom than the pain group (22.9% vs 9.0%). There is a significant tendency for patients to report their defecatory and non-defecatory abdominal symptom as pain alone, or discomfort alone, or pain & discomfort (all P < 0.001).

CONCLUSION

IBS patients with abdominal discomfort have similar bowel symptoms and psychosocial features to those with abdominal pain. IBS symptoms manifesting abdominal pain or discomfort may primarily be due to different sensation and reporting experience.

A poor diet quality is associated with more gas-related symptoms and a decreased quality of life in French adults

This study evaluated the association between dietary patterns, Gas-Related Symptoms (GRS) and their impact on quality of life (QoL) in a representative sample (n=936) of the French adult population. During the 2018-2019 "Comportements et Consommations Alimentaires en France" (CCAF) survey (Behaviors and Food Consumption in France), online evaluation of GRS in adult participants was performed using the validated Intestinal Gas Questionnaire (IGQ), which captures the perception of GRS and their impact on QoL via 6 symptom dimensions scores (range 0-100; 100=worse) and a global score (mean of the sum of the 6 symptom dimensions scores). Socio-demographics, lifestyle parameters and dietary habits (7-day e-food diary) were also collected online. Quality of diet was determined using the NRF9.3 score (range 0-900; 900=best). Univariate and multivariate linear regression models were applied to identify factors associated with IGQ global score. K-means was used to identify clusters of subjects based on their dietary records. Data from 936 adults who completed both the IGQ and the food diary showed a mean (SD) IGQ global score of 11.9 (11.2). Younger age and female gender were associated with a higher IGQ global score. Only 7% of subjects reported no symptom at all and nearly 30% of study participants reported a high impact of GRS on their QoL. Two dietary clusters were identified: cluster1, characterized by a higher consumption of fruits and vegetables, lower sugars intake and higher NRF9.3 score and cluster 2, characterized by higher intake of sugars, lower intake in dietary fibers and lower NRF9.3 score. The IGQ global score was lower in cluster1 and higher in cluster2 vs. the total sample average (p<0.001). Prevalence of GRS in the French adult population is high and is associated with impaired QoL and dietary patterns. A change in food habits towards healthier patterns could help reducing the burden of GRS.

Irritable Bowel Syndrome Demographics: A Middle Eastern Multinational Cross-sectional Study

BACKGROUND: Irritable bowel syndrome (IBS) is the most frequent functional gastrointestinal (GI) disorder. In this study, we aimed to evaluate the different aspects of IBS among Middle Eastern residents. METHODS: During the study period, patients attending gastroenterology clinics of nine tertiary referral centers in four Middle Eastern couturiers (Iran, Egypt, Kuwait, and Turkey) were evaluated by Rome IV diagnostic criteria, and those who fulfilled the diagnostic criteria of IBS were asked to fill in a questionnaire covering different demographics and clinical aspects. RESULTS: Overall, during a 6-month period, 509 patients with IBS were included. 41.3% of the participants were male (210 patients), and 37.4% of them had academic education. 50% of the participants were Caucasian, and 34% were Arab, and originally, they were citizens of 18 countries. 77.4% of the participants were residents of subtropical areas, while 22.2% were living in temperate regions. The average age of the participants during the first presentation in subtropical and temperate areas were 38.4 ± 12.19 and 38.06 ± 12.18 years, respectively (P = 0.726). The most common subtypes of IBS in subtropical areas were unclassified (IBS-U, 44.4%), constipation dominant (IBS-C, 27.6%), mixed pattern (IBS-M, 21%), and diarrhea dominant (IBS-D, 6.8%) in descending order while in temperate areas the most common subtypes were IBS-U (43.3%), and IBS-D (22.1%), respectively (P < 0.001). Besides abdominal pain, the most common symptom of patients in each region was bloating (62.2% and 68.1%, respectively, P = 0.246). The rate of depression and anxiety were significantly higher among the residents of temperate areas in comparison with subtropical regions (41.6% vs. 16.5% and 80.5% vs. 58.4%, respectively, P < 0.001). CONCLUSION: Although the average age of IBS presentation is the same in subtropical and temperate areas, it seems that in temperate areas, the rate of IBS-D is more prevalent than in subtropical regions. The rate of anxiety and depression are significantly higher among those who searched social media and the internet to get information about their problems.

The Intestinal Gas Questionnaire (IGQ): Psychometric validation of a new instrument for measuring gas-related symptoms and their impact on daily life among general population and irritable bowel syndrome

BACKGROUND

Gas-related symptoms (GRS) are common in the general population (GPop) and among patients with disorders of gut-brain interactions but there is no patient-reported outcome evaluating these symptoms and their impact on daily life. We have previously developed a 43-item intestinal gas questionnaire (IGQ). The aim of the present study is to perform a psychometric validation of this instrument.

METHODS

Participants (119 from the GPop and 186 irritable bowel syndrome (IBS) patients) were recruited from 3 countries (UK, Spain, France). IBS patients fulfilled ROME IV criteria with an IBS severity score between 150 and 300. Participants completed the IGQ, the functional Digestive Disorders Quality of Life (FDDQL), and the EQ-5D. A subgroup (n = 90) repeated the IGQ completion after 7 days on paper or electronically.

RESULTS

From the original IGQ questionnaire, 26 items were deleted because of poor performance. Confirmatory factorial analysis on the remaining 17 items (7 symptom and 10 impact items) yielded a 6-factor structure accounting for 67% of the variance for bloating (6 items), flatulence (3), belching (2), bad breath (2), stomach rumbling (2), and difficult gas evacuation (2). Global score (0-100) was worse among IBS vs GPop (40 ± 15 vs 33 ± 17; p = 0.0016). At the second visit, the intraclass correlation coefficient of IGQ scores was between 0.71 and 0.86 (n = 67) for test-retest reliability and 0.61-0.87 (n = 64) for equivalence between electronic and paper versions of IGQ.

CONCLUSION

The IGQ available in paper and electronic versions in 3 languages is a robust instrument for capturing and measuring GRS and their impact on daily life.

Maintaining work life under threat of symptoms: a grounded theory study of work life experiences in persons with Irritable Bowel Syndrome

Background

Irritable Bowel Syndrome (IBS) is a highly prevalent functional gastrointestinal disorder. Earlier studies have shown that IBS can limit the ability to perform at work and lead to absenteeism. However, few studies focus on work life experiences based on patients’ narratives. The purpose of this study was to construct a theory for how persons with IBS maintain their work life.

Methods

A qualitative study was performed using constructivist grounded theory. Semi-structured interviews with 15 women and 8 men with IBS (26–64 years of age) were conducted. Fourteen participants worked full-time, six worked part-time and three were on sick leave. The interviews were transcribed verbatim and coded line-by-line, incident-by-incident and thereafter focused coding was done. From the data and codes, categories were generated. Finally, a core category was constructed explaining the process of maintaining work life when living with IBS.

Results

Balancing work life while being under threat of symptoms constituted of four categories, being prepared, restricting impact, reconciling and adjusting. Persons with IBS restricted the impact of IBS on work by using strategies and upholding daily routines and strived to being prepared by exerting control over work life. These ongoing processes served to limit the influence of IBS on work by symptoms being less intense, perceived as less frequent, or not as bothersome. Reconciling IBS with work life was understood as a successful outcome from being prepared and restricting impact but was also influenced by the individual’s outlook on life. Adjusting to other people at work interfered with the strategies of being prepared, restricting impact, and reconciling, leaving persons with IBS more susceptible to symptoms.

Conclusions

This study deepens the understanding of the work situation for persons with IBS. Health care professionals can use the results of this study in the dialogue with the patient discussing work ability and sick leave. The results imply that although balancing work life under threat of symptoms can be a struggle, there are strategies that persons with IBS and employers together can initiate and use to reduce impact on work on several different levels.

Beneficial Effects on Abdominal Bloating with an Innovative Food-Grade Formulation of Curcuma longa and Boswellia serrata Extracts in Subjects with Irritable Bowel Syndrome and Small Bowel Dysbiosis

Bloating is a symptom frequently reported by subjects with irritable bowel syndrome (IBS) and small bowel dysbiosis, and Low FODMAP’s diet (LFD) has been used to treat them. Extracts of Curcumalonga and Boswelliaserrata share anti-inflammatory and antimicrobial effects that could be useful in the management of these clinical conditions. The aim of this study was to evaluate the efficacy of curcumin and boswellia extracts (as Curcumin Boswellia Phytosome, CBP) and LFD on the relief of abdominal bloating in IBS subjects with small bowel dysbiosis, in comparison to LFD alone, in a 30-day supplementation, randomized trial. IBS participants were randomized to either the intervention (500 mg bid of CBP and LFD) or control arm (LFD). Small bowel dysbiosis has been defined by an increase of urinary indican with normal urinary skatole. A total of 67 subjects were recruited. The intervention group (33 subjects) showed a significant decrease (p < 0.0001) of bloating, abdominal pain, and indican values at the end of the study, when compared to the control group (34 subjects). Moreover, the subjects of the intervention group showed a significantly better (p < 0.0001) global assessment of efficacy (GAE) as compared to controls. In conclusion, in subjects with IBS and small bowel dysbiosis, abdominal bloating can be successfully reduced with a supplementation with CBP and LFD.

A Phenotypic Comparison of Loudness and Pain Hyperacusis: Symptoms, Comorbidity, and Associated Features in a Multinational Patient Registry

Purpose Hyperacusis is a complex and poorly understood auditory disorder characterized by decreased tolerance to sound at levels that would not trouble most individuals. Recently, it has been suggested that individuals who experience otalgia in response to everyday sounds (termed pain hyperacusis) may differ clinically from those whose primary symptom is the perception of everyday sounds as excessively loud (termed loudness hyperacusis). Despite this theoretical distinction, there have been no empirical studies directly comparing these two populations of hyperacusis patients. Method Using data from a multinational patient registry (the Coordination of Rare Diseases at Sanford Registry), we examined self-reported demographics, symptoms, comorbidity, and response to treatment in a sample of 243 adults with hyperacusis, 152 of whom were classified as having pain hyperacusis based on reported symptoms. Bayesian statistical tests were used to investigate both the presence and absence of group differences between patients with loudness and pain hyperacusis. Results Individuals with pain hyperacusis presented with a more severe clinical phenotype, reporting a higher frequency of temporary symptom exacerbations (i.e., "setbacks"), less perceived symptom improvement over time, more severe comorbid headache disorders, and reduced benefit from sound therapy. However, the two hypothesized hyperacusis subtypes exhibited more similarities than differences, with the majority of symptoms and comorbidities being equally prevalent across groups. Multiple comorbidities were commonly observed, including tinnitus, primary headache disorders, psychiatric disorders, and functional somatic syndromes. Intolerance of sensory stimuli in other modalities was also frequently reported. Conclusion Although this study provides little evidence that loudness and pain hyperacusis are pathophysiologically distinct conditions, our findings indicate that a pain-predominant phenotype may be a meaningful prognostic marker in patients with hyperacusis.

Efficacy of Tenapanor in Treating Patients With Irritable Bowel Syndrome With Constipation: A 26-Week, Placebo-Controlled Phase 3 Trial (T3MPO-2)

INTRODUCTION

Tenapanor is a first-in-class, minimally absorbed, small-molecule inhibitor of the gastrointestinal sodium/hydrogen exchanger isoform 3. This phase 3 trial assessed the long-term efficacy and safety of tenapanor 50 mg b.i.d. for the treatment of patients with irritable bowel syndrome with constipation (IBS-C).

METHODS

In this randomized double-blind study (ClinicalTrials.gov identifier: NCT02686138), patients with IBS-C received tenapanor 50 mg b.i.d. or placebo b.i.d. for 26 weeks. The primary endpoint was the proportion of patients who had a reduction of ≥30.0% in average weekly worst abdominal pain and an increase of ≥1 weekly complete spontaneous bowel movement from baseline, both in the same week, for ≥6 of the first 12 treatment weeks (6/12-week combined responder).

RESULTS

Of the 620 randomized patients with IBS-C, 593 (95.6%) were included in the intention-to-treat analysis set (tenapanor: n = 293; placebo: n = 300) and 481 patients (77.6%) completed the 26-week treatment period. In the intention-to-treat analysis set (mean age: 45.4 years; 82.1% women), a significantly greater proportion of patients treated with tenapanor were 6/12-week combined responders than those treated with placebo (36.5% vs 23.7%; P < 0.001). Abdominal symptoms and global symptoms of IBS were significantly improved with tenapanor compared with placebo. Diarrhea, the most common adverse event, was typically transient and mild to moderate in severity. Diarrhea led to study drug discontinuation for 19 (6.5%) and 2 patients (0.7%) receiving tenapanor and placebo, respectively.

DISCUSSION

Tenapanor 50 mg b.i.d. improved IBS-C symptoms over 26 weeks and was generally well tolerated, offering a potential new long-term treatment option for patients with IBS-C (see Visual abstract, Supplementary Digital Content 1, http://links.lww.com/AJG/B797).

Validity and Reliability of the Malay Versions of Bloating Severity (BSQ-M) and Quality of Life (BLQoL-M) Questionnaires

Abdominal bloating (AB) is a prevalent and bothersome symptom, but there are no specific measures for severity and quality of life (QoL) other than the Bloating Severity Questionnaire (BSQ) and Bloating Quality of Life (BLQoL). We aimed to translate the BSQ and BLQoL into the Malay language and to validate them using exploratory factor analysis (EFA) and confirmatory factor analysis (CFA) approaches. The 12-item BSQ has two components, seven-item severity in general (SevGen) and five-item severity in the past 24 h (Sev24), and BLQOL has five items. Translation to the Malay language (BSQ-M and BLQoL-M) was performed using standard forward and backward processes. EFA followed by CFA were performed in participants with AB due to functional bowel disorders, with the purpose of examining the validity and reliability of the questionnaires translated into Malay. After EFA with 152 participants, all the items of BSQ-M remained in the model. Total variance extracted was 53.26% for BSQ-M and 58.79% for BLQoL-M. The internal consistency based on Cronbach's alpha values was 0.52 for SevGen, 0.86 for Sev24, and 0.81 for BLQoL-M. After performing CFA with another 323 participants, the final measurement model for BSQ-M and BLQoL-M fit the data well in terms of several fit indices (BSQ-M: root mean square error of approximation (RMSEA) = 0.050, Comparative Fit Index (CFI) = 0.966, Tucker-Lewis Fit Index (TLI) = 0.956, and standardized root mean squared residual (SRMR) = 0.051; BLQoL-M: RMSEA = 0.071, CFI = 0.985, TLI = 0.962, SRMR = 0.021). The composite reliability for BSQ-M and BLQoL-M were satisfactory (SevGen = 0.83, Sev24 = 0.89, BLQoL = 0.80). The intraclass correlation (ICC) results showed excellent stability for BSQ-M and BLQoL-M, ranging from 0.74 to 0.93. The Malay language versions of BSQ-M and BLQoL-M are valid and reliable instruments for measuring the severity and QoL of AB for the Asian population with functional bowel disorders.

Efficacy and Safety of 5-HT4 Receptor Agonist Minesapride for Irritable Bowel Syndrome with Constipation in a Randomized Controlled Trial

BACKGROUND & AIMS

Treatment options for irritable bowel syndrome with constipation (IBS-C) are limited-new prokinetic drugs are needed. We evaluated the efficacy and safety of minesapride (DSP-6952), a partial agonist with high affinity for 5-HT4 receptors, in patients with IBS-C in Japan.

METHODS

We performed a double-blind phase 2 study of 171 patients with Rome III-defined IBS-C at 33 centers in Japan, from December 2012 through August 2013. Patients were randomly assigned to groups given minesapride (1, 4, 12, or 40 mg) or placebo once daily for 4 weeks. The primary outcome was efficacy, defined as improvement in the weekly frequency of complete spontaneous bowel movements (CSBMs), abdominal symptoms, and IBS-C symptoms (according to the Japanese version of the IBS severity index score). For evaluation of safety, adverse events (AEs) were recorded.

RESULTS

The least squares mean change from baseline in the weekly frequency of CSBMs was greater in all minesapride groups than in the placebo group at week 4 (40 mg vs placebo, P = .040). The abdominal symptoms score improved in minesapride 40 mg group. The overall IBS severity index score decreased from baseline to week 4 in all treatment groups-especially in the 12 mg and 40 mg groups (P = .048 and <.001 vs placebo, respectively). The proportions of patients with treatment-emergent AEs in the pooled minesapride and placebo groups were 55.0% and 60.0%, respectively. The most common treatment-emergent AE was diarrhea (in 42.9% and 37.1% of patients in the pooled minesapride and placebo groups, respectively).

CONCLUSIONS

In a phase 2 trial of patients with IBS-C in Japan, minesapride increased stool frequency (measured by CSBMs), reduced abdominal and overall IBS-C symptoms, and was well tolerated. Japan Pharmaceutical Information Center trial no: JapicCTI-122041.

Fecal Microbiota Alterations and Small Intestinal Bacterial Overgrowth in Functional Abdominal Bloating/Distention

Background/Aims

The pathophysiology of functional abdominal bloating and distention (FABD) is unclear yet. Our aim is to compare the diversity and composition of fecal microbiota in patients with FABD and healthy individuals, and to evaluate the relationship between small intestinal bacterial overgrowth (SIBO) and dysbiosis.

Methods

The microbiota of fecal samples was analyzed from 33 subjects, including 12 healthy controls and 21 patients with FABD diagnosed by the Rome IV criteria. FABD patients underwent a hydrogen breath test. Fecal microbiota composition was determined by 16S ribosomal RNA amplification and sequencing.

Results

Overall fecal microbiota composition of the FABD group differed from that of the control group. Microbial diversity was significantly lower in the FABD group than in the control group. Significantly higher proportion of Proteobacteria and significantly lower proportion of Actinobacteria were observed in FABD patients, compared with healthy controls. Compared with healthy controls, significantly higher proportion of Faecalibacterium in FABD patients and significantly higher proportion of Prevotella and Faecalibacterium in SIBO (+) patients with FABD were found. Faecalibacterium prausnitzii, was significantly more abundant, but Bacteroides uniformis and Bifidobacterium adolescentis were significantly less abundant in patients with FABD, compared with healthy controls. Significantly more abundant Prevotella copri and F. prausnitzii, and significantly less abundant B. uniformis and B. adolescentis were observed in SIBO (+) patients, compared with healthy controls.

Conclusion

The fecal microbiota profiles in FABD patients are different from those in healthy controls, particularly in SIBO (+) patients, suggesting a role of gut microbiota in the pathogenesis of FABD.

Intake of okara soup for 2 weeks for breakfast improved defecation habits in young Japanese women with self-reported constipation: A randomized, double-blind, placebo-controlled, intervention study

Okara is a byproduct of soymilk manufacturing and a rich source of protein and dietary fiber. We investigated whether okara intake improves the habit of defecation in young Japanese women (n = 52) with self-reported constipation. Subjects were categorized into placebo and test groups, who ingested soymilk (0.1 g fiber/meal) and okara (4.1 g fiber/meal) soups, respectively, every day for breakfast, for 2 weeks. Subjects' body composition, bowel movement frequency per week, and constipation assessment scale (CAS) and brief-type self-administered diet history questionnaire scores were assessed at baseline and after the intervention (Analysis 1). Further, subjects' bowel movement frequency per week and CAS scores were assessed during the 2-week follow-up (Analysis 2). There were no significant differences in age, anthropometric characteristics, nutrients intake, frequency of bowel movements per week, and total CAS scores between the placebo and test groups at baseline. After intervention, the total CAS score was significantly lower in the test group than in the placebo group. Moreover, the difference in the total CAS scores between baseline and after intervention was lower in the test group than in the placebo group, although not significant. The weekly frequency of bowel movement significantly increased for both placebo and test groups. The test group reported reduced abdominal bloating 2 weeks after the intervention, but the placebo group did not. The findings suggest that okara is effective in increasing the frequency of bowel movements and improving defecation habit in young women with self-reported constipation. PRACTICAL APPLICATION: Okara is an effective food to increase the frequency of bowel movements and to improve defecation habits in young women with self-reported constipation.

Global burden of irritable bowel syndrome: trends, predictions and risk factors

Irritable bowel syndrome (IBS) is one of the most common disorders of gut-brain interaction worldwide, defined according to patterns of gastrointestinal symptoms as described by the Rome diagnostic criteria. However, these criteria, developed with reference to research conducted largely in Western populations, might be limited in their applicability to other countries and cultures. Epidemiological data show a wide variation in the prevalence of IBS globally and more rigorous studies are needed to accurately determine any differences that might exist between countries as well as the potential explanations. The effects of IBS on the individual, in terms of their quality of life, and on health-care delivery and society, in terms of economic costs, are considerable. Although the magnitude of these effects seems to be comparable between nations, their precise nature can vary based on the existence of societal and cultural differences. The pathophysiology of IBS is complex and incompletely understood; genetics, diet and the gut microbiome are all recognized risk factors, but the part they play might be influenced by geography and culture, and hence their relative importance might vary between countries. This Review aims to provide an overview of the burden of IBS in a global context, to discuss future implications for the care of people with IBS worldwide, and to identify key areas for further research.

Global prevalence of irritable bowel syndrome according to Rome III or IV criteria: a systematic review and meta-analysis

BACKGROUND

Irritable bowel syndrome (IBS) is one of the most common functional bowel disorders, but community prevalence appears to vary widely between different countries. This variation might be due to the fact that previous cross-sectional surveys have neither applied uniform diagnostic criteria nor used identical methodology, rather than being due to true global variability. We aimed to determine the global prevalence of IBS.

METHODS

We did a systematic review and meta-analysis of data from all population-based studies using relatively uniform methodology and using only the most recent iterations of the Rome criteria (Rome III and IV). We searched MEDLINE, Embase, and Embase Classic (from Jan 1, 2006, to April 30, 2020) to identify cross-sectional surveys reporting the prevalence of IBS in adults (≥90% of participants aged ≥18 years) according to the Rome III or Rome IV criteria. We also hand-searched a selection of conference proceedings for relevant abstracts published between 2006 and 2019. We extracted prevalence data for all studies, according to the criteria used to define the presence of IBS. We did a meta-analysis to estimate pooled prevalence rates, according to study location and certain other characteristics (eg, sex and IBS subtype).

FINDINGS

We identified 4143 citations, of which 184 studies appeared relevant. 57 of these studies were eligible, and represented 92 separate adult populations, comprising 423 362 participants. The pooled prevalence of IBS in 53 studies that used the Rome III criteria, from 38 countries and comprising 395 385 participants, was 9·2% (95% CI 7·6-10·8; I²=99·7%). By contrast, pooled IBS prevalence among six studies that used the Rome IV criteria, from 34 countries and comprising 82 476 individuals, was 3·8% (95% CI 3·1-4·5; I²=96·6%). IBS with mixed bowel habit (IBS-M) was the most common subtype with the Rome III criteria, reported by 33·8% (95% CI 27·8-40·0; I²=98·1%) of people fulfilling criteria for IBS (ie, 3·7% [2·6-4·9] of all included participants had IBS-M), but IBS with diarrhoea (IBS-D) was the most common subtype with the Rome IV criteria (reported by 31·5% [95% CI 23·2-40·5; I²=98·1% 61·6%] of people with IBS, corresponding to 1·4% [0·9-1·9] of all included participants having IBS-D). The prevalence of IBS was higher in women than in men (12·0% [95% CI 9·3-15·0] vs 8·6% [6·3-11·2]; odds ratio 1·46 [95% CI 1·33-1·59]). Prevalence varied substantially between individual countries, and this variability persisted even when the same diagnostic criteria were applied and identical methodology was used in studies.

INTERPRETATION

Even when uniform symptom-based criteria are applied, based on identical methodology, to define the presence of IBS, prevalence varies substantially between countries. Prevalence was substantially lower with the Rome IV criteria, suggesting that these more restrictive criteria might be less suitable than Rome III for population-based epidemiological surveys.

FUNDING

None.

Efficacy of Tenapanor in Treating Patients With Irritable Bowel Syndrome With Constipation: A 12-Week, Placebo-Controlled Phase 3 Trial (T3MPO-1)

OBJECTIVES

Tenapanor is a first-in-class, minimally absorbed, small-molecule inhibitor of the gastrointestinal sodium/hydrogen exchanger isoform 3. This phase 3 trial assessed the efficacy and safety of tenapanor 50 mg b.i.d. for the treatment of patients with constipation-predominant irritable bowel syndrome (IBS-C).

METHODS

In this phase 3, double-blind study (ClinicalTrials.gov identifier NCT02621892), patients with IBS-C were randomized to tenapanor 50 mg b.i.d. or placebo b.i.d. for 12 weeks followed by a 4-week randomized withdrawal period. The primary efficacy variable was the proportion of patients who reported a reduction in average weekly worst abdominal pain of ≥30.0% and an increase of ≥1 complete spontaneous bowel movement from baseline, both in the same week, for ≥6 weeks of the 12-week treatment period.

RESULTS

Of the 629 randomized patients with IBS-C, 606 (96.3%) were included in the intention-to-treat analysis set (tenapanor: n = 307; placebo: n = 299) and 533 (84.7%) completed the 12-week treatment period. In the intention-to-treat analysis set (mean age 45 years, 81.4% women), a significantly greater proportion of patients treated with tenapanor met the primary endpoint than patients treated with placebo (27.0% vs 18.7%, P = 0.020). Abdominal symptoms and global symptoms of IBS also improved with tenapanor (P < 0.05 vs placebo). Diarrhea was the most commonly reported adverse event, resulting in study drug discontinuation in 6.5% and 0.7% of patients receiving tenapanor and placebo, respectively, during the 12-week treatment period.

DISCUSSION

Tenapanor 50 mg b.i.d. improved IBS-C symptoms and was generally well tolerated, offering a potential new treatment option for patients with IBS-C.

Internet survey on the actual situation of constipation in the Japanese population under 70 years old: focus on functional constipation and constipation-predominant irritable bowel syndrome

BACKGROUND

In Japan, the prevalence of constipation-predominant irritable bowel syndrome (IBS-C) and functional constipation (FC) diagnosed by the Rome III criteria is unclear, as are the demographic profile, quality of life (QOL), and habits of persons with IBS-C or FC.

METHODS

We performed an internet survey of constipation. After extracting 3000 persons fitting the composition of the general Japanese population, we investigated demographic factors, lifestyle, defecation, and laxatives. IBS-C and FC were diagnosed by Rome III criteria. Respondents also completed the Japanese IBS severity index (IBS-SI-J), Japanese IBS QOL scale (IBS-QOL-J), SF-8, Hospital Anxiety and Depression Scale (HADS), and Japanese Health Practice Index (JHPI).

RESULTS

There were 262 respondents with FC (8.73%) [73 men and 189 women; mean age: 49.8 ± 13.1 years; mean body mass index (BMI): 21.0 ± 3.3 g/m²] and 149 respondents with IBS-C (4.97%) (76 men and 73 women; mean age; 41.6 ± 13.7 years; mean BMI: 20.8 ± 3.0 kg/m²). Total IBS-QOL-J score were significantly lower in the IBS-C group than the FC group. With regard to SF-8, score of mental component summary (MCS) was significantly lower in the IBS-C group. The total IBS-SI-J score and item scores, except for satisfactory defecation, were significantly higher in the IBS-C group than the FC group. HADS showed a significant increase of anxiety and depression in both the groups, and the JHPI revealed insufficient sleep.

CONCLUSIONS

In Japan, among the population of under 70 years old, the prevalence of IBS-C and FC (Rome III criteria) was 4.97% and 8.76%, respectively. IBS-C caused more severe symptoms than FC, resulting in impairment of QOL.

Mass spectrometry-based metabolomics for irritable bowel syndrome biomarkers

BACKGROUND

Irritable bowel syndrome (IBS) is a common gastrointestinal disorder without obvious structural abnormalities or consistent associated biomarkers, making its diagnosis difficult. In the present study, we used a urine-based metabolomics approach to identify IBS biomarkers.

METHODS

We used an ultra-performance liquid chromatography/quadrupole time-of-flight mass spectrometry (UPLC-QTOF-MS) on urine samples from patients suffering from IBS and healthy controls. Data were coupled for multivariate statistical analysis methods.

RESULTS

We selected 30 differential metabolites associated with IBS and found steroid hormone biosynthesis and histidine metabolism alterations in patients with IBS that may be involved in the pathogenesis of the disease. In addition, we identified a panel of five metabolite markers composed of cortisone, citric acid, tiglylcarnitine, N6,-N6,-N6-trimethyl-L-lysine and L-histidine that could be used to discriminate between patients and healthy controls and may be appropriate as IBS diagnosis biomarkers.

CONCLUSION

Our findings indicate that metabolomics combined with pattern recognition can be useful to identify disease diagnostic IBS markers.

CLINICAL TRIAL REGISTRATION

ChiCTR1800020072.

How much bloating in the irritable bowel syndrome?

The irritable bowel syndrome (IBS) is the most common chronic gastrointestinal disorder referred to gastroenterologists. One of the most common manifestations of IBS is bloating. Abdominal bloating is defined as subjective sensation of abdominal distension associated with girth increment. Therefore, it is described in the Rome IV criteria as bloating/abdominal distension. Bloating symptoms are reported by 10-30% of the general population and it was rated as the most bothersome symptom by 60% of IBS patients; the lack of specificity of this complaint prevented bloating to be included between the diagnostic criteria for IBS. Indeed, bloating may be reported also in healthy people or in other functional conditions. This paper looks to the evolutions of the concepts on bloating according to the Rome working groups from the beginning until now and it represents a comprehensive review on the prevalence and pathogenesis of bloating.

Effects of the DASH Diet and Sodium Intake on Bloating: Results From the DASH-Sodium Trial

INTRODUCTION

Bloating is one of the most common gastrointestinal complaints. Evidence has linked fiber and sodium to bloating; however, randomized trials examining these diet components are lacking. Here, we used a randomized trial to examine the effects of the high-fiber DASH diet and dietary sodium intake on abdominal bloating. We hypothesized that both the high-fiber DASH diet and higher sodium intake would increase bloating.

METHODS

The DASH-Sodium trial (1998-1999) randomized healthy adults to a high-fiber (32 g/d) DASH or low-fiber (11 g/d) Western diet (control). On their assigned diet, participants ate 3 sodium levels (50, 100, and 150 mmol/d at 2100 kcal) in 30-day periods in random order, with 5-day breaks between each period. The participants reported the presence of bloating at baseline and after each feeding period. Statistical analyses included log-binomial models to evaluate the risk of bloating.

RESULTS

Of 412 participants (mean age 48 years; 57% women; 57% black), 36.7% reported bloating at baseline. Regardless of the diet, high sodium intake increased the risk of bloating (risk ratio = 1.27; 95% confidence interval: 1.06-1.52; P = 0.01). The high-fiber DASH diet also increased the risk of bloating over all sodium levels (risk ratio = 1.41; 95% confidence interval: 1.22-1.64; P < 0.001). The effect of high-fiber DASH on bloating was greater in men than in women (P for interaction = 0.001).

DISCUSSION

Higher dietary sodium increased bloating, as did the high-fiber DASH diet. Although healthful high-fiber diets may increase bloating, these effects may be partially mitigated by decreasing dietary sodium intake. Future research is needed to explore mechanisms by which sodium intake and diet can influence bloating.

Second Asian Consensus on Irritable Bowel Syndrome

BACKGROUND/AIMS

There has been major progress in our understanding of the irritable bowel syndrome (IBS), and novel treatment classes have emerged. The Rome IV guidelines were published in 2016 and together with the growing body of Asian data on IBS, we felt it is timely to update the Asian IBS Consensus.

METHODS

Key opinion leaders from Asian countries were organized into 4 teams to review 4 themes: symptoms and epidemiology, pathophysiology, diagnosis and investigations, and lifestyle modifications and treatments. The consensus development process was carried out by using a modified Delphi method.

RESULTS

Thirty-seven statements were developed. Asian data substantiate the current global viewpoint that IBS is a disorder of gut-brain interaction. Socio-cultural and environmental factors in Asia appear to influence the greater overlap between IBS and upper gastrointestinal symptoms. New classes of treatments comprising low fermentable oligo-, di-, monosacharides, and polyols diet, probiotics, non-absorbable antibiotics, and secretagogues have good evidence base for their efficacy.

CONCLUSIONS

Our consensus is that all patients with functional gastrointestinal disorders should be evaluated comprehensively with a view to holistic management. Physicians should be encouraged to take a positive attitude to the treatment outcomes for IBS patients.

Specific foods can reduce symptoms of irritable bowel syndrome and functional constipation: a review

Background

Functional gastrointestinal disorders (FGIDs) are groups of disorders involving digestive symptoms that chronically persist despite the absence of organic abnormalities in the gastrointestinal tract. Representative FGIDs include functional dyspepsia (FD), irritable bowel syndrome (IBS), and functional constipation (FC). In particular, IBS is a disease representative of FGIDs in which abdominal pain and discomfort associated with abnormal bowel movements chronically persist and recur. These symptoms are known to be related to lifestyle habits, such as meals and stress. In recent years, according to advances in dietary therapy for IBS and FC, specific foods have been shown to alter these symptoms. In IBS, bowel movement abnormalities and abdominal discomfort have been reported to be reduced when patients eat these specific foods.

Main topic

Several studies suggest that individuals with certain attitudes toward eating or with preferences for fatty food, fast food, junk snack food, fried food, and hot/spicy food showed a higher prevalence of gastrointestinal (GI) symptoms. Those who are cognizant of nutritional balance or healthy food intake have a lower prevalence of GI symptoms. Thus, eating specific foods with higher dietary fiber and low FODMAP (fermentable oligosaccharides, disaccharides, monosaccharaides, and polyols) is effective for relief from some GI symptoms.

First, two kinds of dietary fibers are found in foods: water-soluble dietary fiber and insoluble dietary fiber. Enduring misconceptions about the physical effects of fiber in the gut have led to misunderstandings about the health benefits attributable to insoluble and soluble fiber. Previous reviews suggest that health benefits have been shown in regard to fiber, and reproducible evidence of clinical efficacy has been published.

Second, the ingestion of certain carbohydrates causes gastrointestinal symptoms. Foods rich in fermentable oligosaccharides, disaccharides, monosaccharaides, and polyols (collectively known as FODMAP) have been shown to cause abdominal pain and abdominal discomfort in westerners with IBS.

Conclusion

Dietary therapy for FGIDs should include specific foods that have been scientifically proven to be effective for managing symptoms of irritable bowel syndrome and functional constipation.

Bloating in Irritable Bowel Syndrome Is Associated with Symptoms Severity, Psychological Factors, and Comorbidities

BACKGROUND

Bloating is one of the most bothersome symptoms of irritable bowel syndrome (IBS), but its association with other symptoms is not well described.

AIMS

We investigated the association between symptoms of abdominal bloating, other IBS symptoms, psychological distress, and comorbid pain conditions.

METHODS

We conducted a cross-sectional study on a large cohort of IBS patients with and without symptoms of abdominal bloating and healthy controls. Subjects were assessed for IBS and its subtypes, pain severity, symptoms severity, psychological disturbances, comorbidities, and dietary restrictions of three fluid groups.

RESULTS

A total of 484 subjects were investigated. Compared with IBS - B, IBS + B subjects had higher rates of constipation (30% vs. 15%, p = 0.191) and lower rates of diarrhea, (70% vs. 85%, p = 0.191) although these were not statistically significant. Bloating severity correlated with IBS symptoms severity (r = 0.397, p = 0.000), pain severity (r = 0.364, p = 0.000), and both anxiety and somatization scores (r = 0.167, p = 0.015 and r = 0.219, p = 0.001, respectively). Prevalence of fibromyalgia and depression and somatization scores was significantly higher in IBS with bloating than in IBS without bloating. IBS patients with bloating reported more dietary restriction of three fluid groups to control their symptoms compared with healthy controls and IBS patients without bloating.

CONCLUSIONS

Abdominal bloating in IBS is associated with increased symptoms and pain severity, somatization, depression, fibromyalgia, and altered dietary fluids composition. Recognizing and addressing these factors in the diagnosis and management of patients with IBS may improve clinical outcome.

Influence of the requirement for abdominal pain in the diagnosis of irritable bowel syndrome with constipation (IBS-C) under the Rome IV criteria using data from a large Japanese population-based internet survey

BACKGROUND

Rome III was revised to Rome IV in May 2016. One important change in the Rome IV criteria is that abdominal pain must be present for a diagnosis of irritable bowel syndrome (IBS). Under Rome III, in contrast, patients with abdominal discomfort only could be diagnosed with IBS, but these cases under Rome IV are now classified as unspecified functional bowel disorder (FBD). In a simple comparison of Rome III and Rome IV, it is unclear whether this difference reflects the influence of symptomatic frequency or the presence of abdominal pain. In particular, the influence of abdominal pain restriction on the diagnosis of IBS with predominant constipation (IBS-C) in the Rome IV criteria is largely unknown.

METHODS

We reclassified subjects from a Japanese internet survey experiencing abdominal pain or discomfort at least one day each week as surrogate Rome III IBS-C subjects. Among them, we then reclassified subjects experiencing abdominal pain as surrogate Rome IV IBS-C subjects and subjects not experiencing abdominal pain as surrogate Rome IV FBD subjects. Symptoms were quantified and compared between the two groups.

RESULTS

The surrogate Rome IV IBS-C subjects felt a significantly higher degree of anxiety in their daily lives (p < 0.001) compared with the surrogate Rome IV FBD subjects. The combined female and 20-49 years surrogate Rome IV IBS-C subjects felt a higher degree of anxiety in their daily lives (p < 0.05) than the respective Rome IV FBD subjects.

CONCLUSIONS

These results suggest that female IBS-C patients aged 20-49 years with abdominal pain in Rome IV have more anxiety than those without abdominal pain in Rome III. Changes in the diagnostic criteria from Rome III to Rome IV will better identify candidates for the biopsychosocial approach.

TRIAL REGISTRATION

Although this survey was an anonymous internet survey, we obtained informed consent for the study as an online response. The disclosure of this study was approved by the Ethics Committee of Tohoku University Graduate School of Medicine (approval number: 2015-1-405).

Dose-finding study of linaclotide in Japanese patients with chronic constipation: A phase II randomized, double-blind, and placebo-controlled study

BACKGROUND

Based on the previous phase II/III studies of irritable bowel syndrome with constipation (IBS-C) in Japan that demonstrated the efficacy and safety of linaclotide 0.5 mg/d, we evaluated linaclotide at doses of 0.5 mg/d and lower in the treatment of Japanese patients with chronic constipation (CC).

METHODS

This was a phase II randomized, double-blind, placebo-controlled, dose-finding study of linaclotide for Japanese patients with CC (n = 382, 64 men, 318 women, age 20-75). After a baseline period of two weeks, patients were randomized to receive placebo (n = 80), or 0.0625 mg (n = 82), 0.125 mg (n = 71), 0.25 mg (n = 73) or 0.5 mg (n = 76) of linaclotide during a two-week treatment period. The primary efficacy endpoint was change from baseline in weekly spontaneous bowel movement (SBM) frequency during the first week. Secondary endpoints included complete SBM (CSBM) responder rates and IBS-QOL. Safety and adverse events were also evaluated.

KEY RESULTS

The change in SBM frequency during the first week (mean) was 3.89, 3.11, 3.87, and 3.85 for 0.0625 mg, 0.125 mg, 0.25 mg, and 0.5 mg for linaclotide, significantly higher than for placebo (1.91, P < 0.05). The CSBM responder, which is an important parameter, showed the greatest improvement at the 0.5 mg during the 2 week. The most frequent adverse event in the linaclotide groups was diarrhea.

CONCLUSIONS & INFERENCES

Our results suggest that 0.0625, 0.125, 0.25, and 0.5 mg/d are effective doses of linaclotide for treating CC in Japanese patients. ClinicalTrials.gov: NCT02425722, supported by Astellas Pharma, Inc.

Work Productivity and Activity Impairment in Irritable Bowel Syndrome (IBS): A Multifaceted Problem

OBJECTIVES

Patients with irritable bowel syndrome (IBS) are more likely to be both absent from and impaired at work compared to non-IBS patients. We investigated the impact of IBS on work productivity and activity impairment and the relationship to disease specific and general health measures.

METHOD

In total, 525 patients with IBS completed questionnaires assessing work productivity and activity impairment, IBS symptom severity, IBS-related quality of life and GI-specific anxiety. In addition, 155 of the patients completed questionnaires assessing severity of somatic symptoms, depression, anxiety and fatigue. Uni- and bivariate analyses were performed, as well as linear regression to determine factors independently associated with the work productivity and activity impairment measures.

RESULTS

Of employed patients, 24.3% reported absenteeism and 86.8% reported presenteeism because of their IBS. With increasing severity of IBS symptoms and GI-specific anxiety, higher degrees of work impairment were seen. Work productivity impairment in IBS was also associated with low quality of life. GI-specific anxiety was independently associated with absenteeism (R² = 0.23; p < 0.05), IBS-symptom severity and general fatigue with presenteeism (R² = 0.40; p < 0.05), IBS-symptom severity, general fatigue and GI-specific anxiety with overall work loss (R² = 0.50; p < 0.05), and IBS symptom severity and somatic symptoms with activity impairment (R² = 0.38; p < 0.05).

CONCLUSION

Work impairment is a substantial problem in patients with IBS. A combination of IBS and somatic symptom severity, fatigue and psychological factors influence patients' ability to be present, active and productive at work. Based on this, a multidimensional treatment approach for patients with IBS seems logical.

Characterization of Simultaneous Pressure Waves as Biomarkers for Colonic Motility Assessed by High-Resolution Colonic Manometry

Simultaneous pressure waves (SPWs) in manometry recordings of the human colon have been associated with gas expulsion. Our hypothesis was that the SPW might be a critical component of most colonic motor functions, and hence might act as a biomarker for healthy colon motility. To that end, we performed high-resolution colonic manometry (HRCM), for the first time using an 84-sensor (1 cm spaced) water-perfused catheter, in 17 healthy volunteers. Intraluminal pressure patterns were recorded during baseline, proximal and rectal balloon distention, after a meal and following proximal and rectal luminal bisacodyl administration. Quantification was performed using software, based on Image J, developed during this study. Gas expulsion was always associated with SPWs, furthermore, SPWs were associated with water or balloon expulsion. SPWs were prominently emerging at the termination of proximal high amplitude propagating pressure waves (HAPWs); we termed this motor pattern HAPW-SPWs; hence, SPWs were often not a pan-colonic event. SPWs and HAPW-SPWs were observed at baseline with SPW amplitudes of 12.0 ± 8.5 mmHg and 20.2 ± 7.2 mmHg respectively. The SPW occurrence and amplitude significantly increased in response to meal, balloon distention and luminal bisacodyl, associated with 50.3% anal sphincter relaxation at baseline, which significantly increased to 59.0% after a meal, and 69.1% after bisacodyl. Often, full relaxation was achieved. The SPWs associated with gas expulsion had a significantly higher amplitude compared to SPWs without gas expulsion. SPWs could be seen to consist of clusters of high frequency pressure waves, likely associated with a cluster of fast propagating, circular muscle contractions. SPWs were occasionally observed in a highly rhythmic pattern at 1.8 ± 1.2 cycles/min. Unlike HAPWs, the SPWs did not obliterate haustral boundaries thereby explaining how gas can be expelled while solid content can remain restrained by the haustral boundaries. In conclusion, the SPW may become a biomarker for normal gas transit, the gastrocolonic reflex and extrinsic neural reflexes. The SPW assessment reveals coordination of activities in the colon, rectum and anal sphincters. SPWs may become of diagnostic value in patients with colonic dysmotility.

Impact of symptoms by gender and age in Japanese subjects with irritable bowel syndrome with constipation (IBS-C): a large population-based internet survey

Background

Irritable bowel syndrome with constipation (IBS-C) is a representative psychosomatic disorder. Several pathophysiological factors have been linked to IBS symptoms such as the modulation of gastrointestinal motility, visceral hypersensitivity, dysregulation of the gut-brain axis, genetic and environmental factors, sequelae of infection, and psychosocial disorders. It is likely that biopsychosocial aspects of IBS-C underlie its gender and age effects. However, the influence of each symptom of IBS-C by gender and age is not well understood. We hypothesized that the expression rate of each IBS-C symptom in females and in subjects aged 20–49 years was higher than that of subjects who were male and aged 50–79 years.

Methods

We conducted an internet survey of 30,000 adults from the general Japanese population. IBS-C subjects were asked to answer a questionnaire on the degree of anxiety, thoughts about bowel habits, and their dominant gastrointestinal symptoms together with exacerbation factors. The correlation between gender and age and IBS-C symptoms was analyzed.

Results

When analyzed by gender, the expression rate of abdominal discomfort, abdominal distention, and abdominal fullness was significantly higher in female than male IBS-C subjects (66.5% vs. 58.7%, p < 0.05; 54.7% vs. 43.6%, p < 0.01; 18.9% vs. 9.6%, p < 0.01, respectively). When analyzed by age, the expression rate of abdominal distention and abdominal pain was significantly higher among IBS-C subjects aged 20–49 years than those aged 50–79 years (55.7% vs. 46.8%, p < 0.05; 36.6% vs. 20.6%, p < 0.001, respectively). In contrast, there was no gender or age differences with regard to the most common and bothersome symptom (abdominal bloating) among IBS-C subjects.

Conclusions

The expression rate of some IBS-C symptoms was higher among females and those aged 20–49 years than males and those aged 50–79 years, respectively. It is important to understand the impact of symptoms by gender and age to evaluate the pathology of IBS-C from a biopsychosocial perspective.

Trial registration

Although this survey was an anonymous internet survey, we obtained informed consent for the study as an online response. The disclosure of this study was approved by the Ethics Committee of Tohoku University Graduate School of Medicine (approval number: 2015–1-405).

Efficacy, safety, and tolerability of plecanatide in patients with irritable bowel syndrome with constipation: results of two phase 3 randomized clinical trials

OBJECTIVES

Two identical, phase 3, randomized, double-blind, placebo-controlled trials evaluated the efficacy and safety of plecanatide in patients with irritable bowel syndrome with constipation (IBS-C).

METHODS

Adults meeting Rome III criteria for IBS-C were randomized (1:1:1) to placebo or plecanatide (3 or 6 mg) for 12 weeks. The primary efficacy end point was the percentage of overall responders (patients reporting ≥30% reduction from baseline in worst abdominal pain plus an increase of ≥1 complete spontaneous bowel movement (CSBM)/week from baseline in the same week for ≥6 of 12 treatment weeks). Safety was assessed by adverse events (AEs).

RESULTS

Overall, 2189 individuals were randomized across the two studies and 1879 completed the studies. Demographic and baseline characteristics were similar across treatment groups and between studies. The percentage of overall responders in Study 1 was 30.2% and 29.5% for plecanatide 3 and 6 mg, respectively, vs. 17.8% placebo (P < 0.001 for each dose vs. placebo), and in Study 2 was 21.5% (P = 0.009) and 24.0% (P < 0.001) for plecanatide 3 and 6 mg, respectively, compared to 14.2% for placebo. The percentage of sustained efficacy responders (overall responders plus weekly responders for ≥2 of last 4 weeks of the 12-week treatment period) was significantly greater for both doses of plecanatide vs. placebo across both studies. All secondary end points (stool frequency/consistency, straining, abdominal symptoms) showed statistically significant improvements compared with placebo. The most common AE was diarrhea (3 mg, 4.3%; 6 mg, 4.0%; placebo, 1.0%). Discontinuation due to diarrhea was infrequent (3 mg, 1.2%; 6 mg, 1.4%; placebo, 0).

CONCLUSIONS

Plecanatide significantly improved both abdominal pain and constipation symptoms of IBS-C with minimal associated side effects and high levels of tolerability.

Overlap between irritable bowel syndrome and functional dyspepsia including subtype analyses

BACKGROUND AND AIM

Coexistent gastrointestinal symptom profiles and prevalence or associated factors for the overlap between each functional dyspepsia (FD) and irritable bowel syndrome (IBS) group remain unclear. Thus, the aim of the present study was to evaluate the clinicodemographic features of FD, IBS, and IBS-FD overlap and assess the risk factors thereof, including subtype and genetic polymorphisms for IBS-FD.

METHODS

Consecutive patients were enrolled from the outpatient Gastroenterology clinics of Bundang Seoul National University Hospitals in Korea. All gastrointestinal symptoms occurring at least once per week in the previous 3 months were recorded. Diagnostic criteria of functional gastrointestinal disorders were based on the Rome III criteria. Risk factors including genetic polymorphisms of 5-HTTLPR and ADRA2A 1291 G alleles and CCK-1R intron 779T>C were assessed using a multivariate logistic regression model.

RESULTS

A total of 632 subjects (278 control subjects, 308 FD, 156 IBS, and 110 who met the criteria for both FD and IBS) were included in this study. Patients with IBS-FD overlap had more severe symptoms (such as bloating, nausea, vomiting, hard or lumpy stools, defecation straining, and a feeling of incomplete bowel movement) and higher depression scores compared with non-overlap patients. Single/divorced or widowed marital status, nausea, bloating, and a feeling of incomplete emptying after bowel movements were independent risk factors for IBS-FD overlap among IBS patients. In contrast, young age, depression, bloating, and postprandial distress syndrome were positively associated with IBS-FD overlap among FD patients. 5-HTTLPR L/L was a risk factor for the co-occurrence of IBS-C among FD patients (OR: 12.47; 95% CI: 2.00-77.75; P = 0.007).

CONCLUSIONS

Bloating was a risk factor for IBS-FD overlap. Patients with postprandial distress syndrome have a higher risk of coexisting IBS, particularly constipation-dominant IBS.

Nurse-Led Self-Management Educational Intervention Improves Symptoms of Patients With Functional Constipation

This study aimed to evaluate the effects of self-management educational intervention on the symptoms of patients with functional constipation. From January 2014 to April 2015, 66 patients with functional constipation were randomly assigned into intervention group receiving intensive educational interventions and control group receiving routine nursing care. The constipation score of all clinical symptoms (Bristol stool form scale, defecation interval, incomplete evacuation, evacuatory difficulty) at 1 month postdischarge were all significantly lower in the intervention group than in the control group (all, p < .05). At 1 month postdischarge, the intervention group had a significantly higher proportion of patients with good health habits (reasonable diet, regular exercise, good defecation habits, proper use of laxatives) as compared with the control group (all, p < .05). These data suggest educational intervention can effectively improve constipation symptoms and compliance with treatment of patients, and lead to the development of good health habits.

Randomized, placebo-controlled, phase IV pilot study of ramosetron to evaluate the co-primary end points in male patients with irritable bowel syndrome with diarrhea

BACKGROUND

Global assessment allows patients to assess improvement in multiple irritable bowel syndrome (IBS) symptoms. However, it was deemed important to assess "clinically meaningful improvements, focusing on the patient's chief complaint and the severity of major IBS symptoms" in addition to global assessment to show how ramosetron is effective for individual IBS symptoms. This is a pilot study to explore clinical endpoints focusing on the chief complaint of patients with IBS with diarrhea (IBS-D).

METHODS

The same database was used in a previously reported post-marketing phase IV, randomized placebo-controlled pilot trial in male patients with IBS-D. The hypothesis is completely different from that of the other study. Patients with IBS-D diagnosed according to Rome III criteria were given either 5 μg of ramosetron (n = 47) or placebo (n = 51) once daily for 12 weeks after a one-week baseline period. To explore and examine endpoints that allow evaluation of "clinically meaningful improvements focusing on the patient's chief complaint," the chief complaint and its relief by this study drug were assessed in this exploratory study.

RESULTS

Rates of patients with abdominal pain/discomfort, stool form and stool frequency which patients had as a chief complaint before administration were 34.0, 19.1 and 25.5%, respectively, in the ramosetron 5 μg group and 42.0, 18.0, and 20.0% in the placebo group. Responder rates for improvement in symptoms of the chief complaint that patients had before administration were 53.2% in the ramosetron 5 μg group and 42.0% in the placebo group at the last point. The greatest symptomatic improvement in the chief complaint in the ramosetron 5 μg group compared to the placebo group was shown with respect to stool consistency. Bristol Stool Form Scale (BSFS) scores were significantly lower in the ramosetron group than in the placebo group (4.36 ± 1.195 vs 4.85 ± 0.890 at the last point, P = 0.027) throughout the treatment period, except at week 6.

CONCLUSIONS

Ramosetron acted most effectively on stool consistency. Improvement in stool consistency is considered to be a clinically meaningful endpoint in showing how ramosetron was effective for individual IBS symptoms. (Clinicaltrials.gov ID: NCT00918411. Registered 9 June 2009).

Study on alterations of physiological functions in aged constipation rats with fluid-deficiency based on metabonomic and microbiology analysis

To clarify how constipation interferes with the normal physiological function of organisms,¹H NMR profiles combined with PCR-DGGE and 16s rRNA gene sequencing were used to investigate the relationship among constipation, metabolite and gut microbiota.