Health-Related Quality of Life in Irritable Bowel Syndrome: A Systematic Review and Meta-analysis

Thalamic Nucleus Reuniens Glutamatergic Neurons Mediate Colorectal Visceral Pain in Mice via 5-HT2B Receptors

Irritable bowel syndrome (IBS) is a common functional bowel disorder characterized by abdominal pain and visceral hypersensitivity. Reducing visceral hypersensitivity is the key to effectively relieving abdominal pain in IBS. Increasing evidence has confirmed that the thalamic nucleus reuniens (Re) and 5-hydroxytryptamine (5-HT) neurotransmitter system play an important role in the development of colorectal visceral pain, whereas the exact mechanisms remain largely unclear. In this study, we found that high expression of the 5-HT2B receptors in the Re glutamatergic neurons promoted colorectal visceral pain. Specifically, we found that neonatal maternal deprivation (NMD) mice exhibited visceral hyperalgesia and enhanced spontaneous synaptic transmission in the Re brain region. Colorectal distension (CRD) stimulation induced a large amount of c-Fos expression in the Re brain region of NMD mice, predominantly in glutamatergic neurons. Furthermore, optogenetic manipulation of glutamatergic neuronal activity in the Re altered colorectal visceral pain responses in CON and NMD mice. In addition, we demonstrated that 5-HT2B receptor expression on the Re glutamatergic neurons was upregulated and ultimately promoted colorectal visceral pain in NMD mice. These findings suggest a critical role of the 5HT2B receptors on the Re glutamatergic neurons in the regulation of colorectal visceral pain.

Nutritional safety and status following a 12-week strict low FODMAP diet in patients with irritable bowel syndrome

BACKGROUND

A low FODMAP diet (LFD) is an established dietary treatment for patients with irritable bowel syndrome (IBS). However, knowledge on the extended effects of the restriction phase regarding nutrient intake, symptom severity, and quality of life (QoL) is sparse. Therefore, our objectives were to evaluate the safety of a dietitian-led 12-week strict LFD on measures of blood biochemistry, nutritional status, symptom severity, and QoL.

METHODS

In this open-label dietitian-led 12-week strict LFD intervention for IBS patients with predominantly diarrhea or mixed stool pattern (IBS-D/-M), we collected data on diet intake (3-day dietary record), overnight fasting routine blood samples, body weight, IBS symptoms (IBS Severity Scoring System (IBS-SSS)), and IBS-related QoL (IBS-QoL) at baseline and after 12 weeks.

KEY RESULTS

Thirty-six participants completed the 12-week follow-up (mean age: 37 years, 67% women, IBS-SSS: 242 (101)). All blood parameters measured were within established reference values at both time points. We found no change in intake of macro- or micronutrients, but several micronutrients were below the recommendations both before and after 12 weeks. BMI slightly decreased, primarily driven by participants with BMI >25 (p < 0.005). QoL improved among most subdomains (p ≤ 0.002), except food avoidance and social reaction.

CONCLUSION

An extended dietitian-guided LFD (12 weeks) is not inferior to the participants' baseline diet, since no clinically meaningful changes in nutritionally related blood samples and no changes in macro- or micronutrient intake were observed. However, the intake of several nutrients was below the recommendations at both time points indicating low diet quality.

Coffee, Alcohol, and Artificial Sweeteners Have Temporal Associations with Gastrointestinal Symptoms

BACKGROUND

Various dietary strategies for managing irritable bowel syndrome (IBS) target mechanisms such as brain-gut interactions, osmotic actions, microbial gas production, and local immune activity. These pathophysiological mechanisms are diverse, making it unclear which foods trigger IBS symptoms for a substantial proportion of patients.

AIM

To identify associations between foods and gastrointestinal symptoms.

METHODS

From the mySymptoms smartphone app, we collected anonymized diaries of food intake and symptoms (abdominal pain, diarrhea, bloating, and gas). We selected diaries that were at least 3 weeks long. The diaries were analyzed for food-symptom associations using a proprietary algorithm. As the participants were anonymous, we conducted an app-wide user survey to identify IBS diagnoses according to Rome IV criteria.

RESULTS

A total of 9,710 food symptom diaries that met the quality criteria were collected. Of the survey respondents, 70% had IBS according to Rome IV criteria. Generally, strong associations existed for caffeinated coffee (diarrhea, 1-2 h postprandial), alcoholic beverages (multiple symptoms, 4-72 h postprandial), and artificial sweeteners (multiple symptoms, 24-72 h postprandial). Histamine-rich food intake was associated with abdominal pain and diarrhea. Some associations are in line with existing literature, whilst the absence of an enriched FODMAP-symptom association contrasts with current knowledge.

CONCLUSIONS

Coffee, alcohol, and artificial sweeteners were associated with GI symptoms in this large IBS-predominant sample. Symptom onset is often within 2 h postprandial, but some foods were associated with a delayed response, possibly an important consideration in implementing dietary recommendations. Clinical trials must test the causality of the demonstrated food-symptom associations.

An Overview of the Effects of Tenapanor on Visceral Hypersensitivity in the Treatment of Irritable Bowel Syndrome with Constipation

Background

Patients with irritable bowel syndrome with constipation (IBS-C) experience persistent abdominal pain, a common symptom leading to greater healthcare utilization and reports of treatment non-response. Clinically significant improvements in abdominal pain were observed in clinical trials of tenapanor, a first-in-class inhibitor of sodium/hydrogen exchanger isoform 3 (NHE3), for the treatment of IBS-C in adults.

Aim

This narrative review reports the current knowledge about visceral hypersensitivity as a mechanism for abdominal pain in patients with IBS-C and explores the published evidence for hypothesized mechanisms by which tenapanor may reduce visceral hypersensitivity leading to the observed clinical response of decreased abdominal pain.

Findings

Abdominal pain is experienced through activation and signaling of nociceptive dorsal root ganglia that innervate the gut. These sensory afferent neurons may become hypersensitized through signaling of transient receptor potential cation channel subfamily V member 1 (TRPV1), resulting in reduced action potential thresholds. TRPV1 signaling is also a key component of the proinflammatory cascade involving mast cell responses to macromolecule exposure following permeation through the intestinal epithelium. Indirect evidence of this pathway is supported by observations of higher pain in association with increased intestinal permeability in patients with IBS. Tenapanor reduces intestinal sodium absorption, leading to increased water retention in the intestinal lumen, thereby improving gastrointestinal motility. In animal models of visceral hypersensitivity, tenapanor normalized visceromotor responses and normalized TRPV1-mediated nociceptive signaling.

Conclusion

By improving gastrointestinal motility, decreasing intestinal permeability and inflammation, and normalizing nociception through decreased TRPV1 signaling, tenapanor may reduce visceral hypersensitivity, leading to less abdominal pain in patients with IBS-C. Therapies that have demonstrated effects on visceral hypersensitivity may be the future direction for meaningful abdominal pain relief for patients with IBS-C.

Worldwide population prevalence and impact of sub-diagnostic gastrointestinal symptoms

BACKGROUND

The Rome Foundation Global Epidemiology Study (RFGES) found that 40.3% of adults in 26 internet-surveyed countries met Rome IV criteria for disorders of gut-brain interaction (DGBI). However, additional people not meeting DGBI criteria may also be burdened by frequent gastrointestinal symptoms.

AIMS

To explore the prevalence and demographic distribution of sub-diagnostic gastrointestinal symptoms, and the hypothesised associated effects on quality of life (QoL), life functioning and healthcare needs.

METHODS

We analysed data from the RFGES survey, which included the Rome IV diagnostic questionnaire and QoL, psychological, work productivity and healthcare questions.

RESULTS

Of the 50,033 people without a history of organic gastrointestinal disorders, 25.3% classified in the sub-diagnostic group (no DGBI but one or more frequent gastrointestinal symptoms), 41.4% had DGBI and 33.4% had no frequent gastrointestinal symptoms (non-GI group). Sub-diagnostic prevalence in different world regions ranged from 22.2% (North America) to 30.5% (Middle East), was slightly higher among males than females and decreased with age. The sub-diagnostic group was intermediate between the non-GI and DGBI groups, and significantly different from both of them on QoL, anxiety, depression, somatisation, healthcare utilisation and life and work impairment.

CONCLUSIONS

One in four adults without organic gastrointestinal disorders or DGBI report frequent gastrointestinal symptoms. This sub-diagnostic group has reduced QoL, greater psychological and non-GI bodily symptoms, impaired work productivity and life activities and greater healthcare use compared to non-GI individuals. This suggests that many in this sub-diagnostic group might benefit from healthcare services or symptom self-management advice.

Quality of Life and Its Psychosocial Predictors among Patients with Disorders of Gut-Brain Interaction: A Comparison with Age- and Sex-Matched Controls

The disorders of gut-brain interaction (DGBIs) are a heterogeneous group of chronic conditions that greatly reduce patients' quality of life (QoL). To date, biopsychosocial factors (such as gastrointestinal symptoms, alexithymia, and interpersonal problems) are believed to contribute to the development and maintenance of DGBIs, but their role in affecting patients' QoL is still under investigation. Out of 141 patients seeking treatment for their gastrointestinal symptoms, 71 were diagnosed with a DGBI (47 females, 66.2%; Mage: 41.49 ± 17.23 years) and were age- and sex-matched to 71 healthy controls (47 females, 66.2%; Mage: 40.45 ± 16.38 years) without any current gastrointestinal symptom or diagnosis. Participants completed a sociodemographic and clinical questionnaire and a survey investigating several psychosocial risk factors. We found greater symptom severity and difficulties in identifying feelings among patients compared to controls. Further, multiple linear regression analyses evidenced that, among patients, higher expressive suppression of emotions, difficulties in identifying feelings and interpersonal problems, and a lower cognitive reappraisal of emotions predicted lower QoL. Data suggest that the QoL of patients with DGBIs is affected not only by common risk factors (e.g., interpersonal problems) but also by specific difficulties in processing and regulating emotions. The implications of these findings are discussed.

The Role of the FODMAP Diet in IBS

The low FODMAP (fermentable oligosaccharide, disaccharide, monosaccharide, and polyol) diet is a beneficial therapeutic approach for patients with irritable bowel syndrome (IBS). However, how the low FODMAP diet works is still not completely understood. These mechanisms encompass not only traditionally known factors such as luminal distension induced by gas and water but also recent evidence on the role of FOMAPs in the modulation of visceral hypersensitivity, increases in intestinal permeability, the induction of microbiota changes, and the production of short-chain fatty acids (SCFAs), as well as metabolomics and alterations in motility. Although most of the supporting evidence is of low quality, recent trials have confirmed its effectiveness, even though the majority of the evidence pertains only to the restriction phase and its effectiveness in relieving abdominal bloating and pain. This review examines potential pathophysiological mechanisms and provides an overview of the existing evidence on the effectiveness of the low FODMAP diet across various IBS subtypes. Key considerations for its use include the challenges and disadvantages associated with its practical implementation, including the need for professional guidance, variations in individual responses, concerns related to microbiota, nutritional deficiencies, the development of constipation, the necessity of excluding an eating disorder before commencing the diet, and the scarcity of long-term data. Despite its recognized efficacy in symptom management, acknowledging these limitations becomes imperative for a nuanced comprehension of the role of a low FODMAP diet in managing IBS. By investigating its potential mechanisms and evidence across IBS subtypes and addressing emerging modulations alongside limitations, this review aims to serve as a valuable resource for healthcare practitioners, researchers, and patients navigating the intricate landscape of IBS.

Clinical trial: predictive factors for response to gut-directed hypnotherapy for refractory irritable bowel syndrome, a post hoc analysis

BACKGROUND

Gut-directed hypnotherapy is effective for patients with irritable bowel syndrome (IBS). Despite its considerable evidence base, gut-directed hypnotherapy is not widely available and remains a limited resource. This emphasises the need to select patients who are most likely to benefit.

AIM

To determine whether baseline patient characteristics were predictive of response to gut-directed hypnotherapy in patients with IBS METHODS: We conducted a secondary analysis of outcomes of 448 patients with refractory Rome III IBS who participated in a randomised study confirming non-inferiority of 6 compared to 12 sessions of gut-directed hypnotherapy. We compared baseline patient characteristics, including age, sex, IBS subtype, quality of life and IBS-Symptom Severity Scale (IBS-SSS), non-colonic symptom score and Hospital Anxiety and Depression (HAD) score between responders and non-responders. We defined response as ≥50-point decrease in IBS-SSS or ≥30% reduction in pain severity scores.

RESULTS

Overall, 76.3% achieved ≥50-point decrease in IBS-SSS. Responders had a higher baseline non-colonic symptom score (p = 0.005). Those who achieved ≥30% improvement in abdominal pain scores (59.8%) had higher baseline IBS-SSS (p = 0.03), and lower baseline HAD-depression score (p = 0.012). Fifty-four patients (12%) dropped out of gut-directed hypnotherapy. Compared to completers, dropouts had higher baseline HAD-anxiety score (p = 0.034).

CONCLUSIONS

These data suggest that patients with a higher burden of gastrointestinal and extraintestinal symptoms are most likely to benefit from gut-specific behavioural intervention for refractory IBS. Clinical assessment of gastrointestinal, somatic and psychological symptom profiles may play a role in selecting patients for gut-directed hypnotherapy.

Exploring the Impact of Covid-19-Related Perceptions on Psychological Distress and Quality of Life in an International Gastrointestinal Cohort Over Time Guided by the Common Sense Model

The aim of this longitudinal study was to examine changes in COVID-19 and illness-related perceptions, gastrointestinal symptoms, coping, catastrophising, psychological distress, and QoL during the COVID-19 pandemic. A total of 831 adults with a gastrointestinal condition completed an online questionnaire at baseline (May-October 2020). Of those, 270 (32.5%) participants (85.2% female, mean age = 47.3 years) provided follow-up data (March-May 2021). Repeated-measures multiple analysis of variance and a cross-lagged panel model were used to test the study hypotheses. Gastrointestinal symptoms and COVID-19 perceptions at follow-up were strongly predicted by their baseline values, while illness perceptions were predicted by baseline gastrointestinal symptoms. Cross-lagged relationships indicated a reciprocal relationship between gastrointestinal symptoms and psychological distress. Moreover, gastrointestinal symptoms had substantial predictive utility, strongly predicting future gastrointestinal symptoms, and to a lesser extent, more negative illness perceptions, greater psychological distress, and greater use of adaptive coping strategies across time.

Update in diagnosis and management of irritable bowel syndrome

Irritable bowel syndrome (IBS) is a functional gastrointestinal disorder characterized by a lack of structural or biochemical abnormalities. The current diagnosis of IBS is based on the Rome IV criteria, and it is recommended to approach IBS patients using a multidimensional clinical profile (MDCP). The pathophysiology of IBS is multifactorial and involves motility disorders, genetic factors, immune responses, visceral hypersensitivity, brain-gut dysregulation, and altered intestinal microbiota. The management of IBS includes both nonpharmacologic and pharmacologic therapies. Nonpharmacologic therapy options include physical activity, low fermentable oligosaccharides, disaccharides, monosaccharides, and polyol diet, as well as cognitive behavioral therapy. Pharmacologic therapy options include probiotics, antidepressants, antispasmodics, and new agents. In clinical practice, a multidisciplinary strategy, including nonpharmacologic or/and pharmacologic treatment for IBS, is emphasized. Therefore, clinicians should carefully consider the underlying pathophysiology before selecting an appropriate therapeutic option for the treatment of IBS. In other words, individualized treatment plans are necessary for managing IBS.

Genetic Variants in Carbohydrate Digestive Enzyme and Transport Genes Associated with Risk of Irritable Bowel Syndrome

Irritable Bowel Syndrome (IBS) is characterized by abdominal pain and alterations in bowel pattern, such as constipation (IBS-C), diarrhea (IBS-D), or mixed (IBS-M). Since malabsorption of ingested carbohydrates (CHO) can cause abdominal symptoms that closely mimic those of IBS, identifying genetic mutations in CHO digestive enzymes associated with IBS symptoms is critical to ascertain IBS pathophysiology. Through candidate gene association studies, we identify several common variants in TREH, SI, SLC5A1 and SLC2A5 that are associated with IBS symptoms. By investigating rare recessive Mendelian or oligogenic inheritance patterns, we identify case-exclusive rare deleterious variation in known disease genes (SI, LCT, ALDOB, and SLC5A1) as well as candidate disease genes (MGAM and SLC5A2), providing potential evidence of monogenic or oligogenic inheritance in a subset of IBS cases. Finally, our data highlight that moderate to severe IBS-associated gastrointestinal symptoms are often observed in IBS cases carrying one or more of deleterious rare variants.

Fibromyalgia and Irritable Bowel Syndrome Interaction: A Possible Role for Gut Microbiota and Gut-Brain Axis

Fibromyalgia (FM) is a serious chronic pain syndrome, characterised by muscle and joint stiffness, insomnia, fatigue, mood disorders, cognitive dysfunction, anxiety, depression and intestinal irritability. Irritable Bowel Syndrome (IBS) shares many of these symptoms, and FM and IBS frequently co-exist, which suggests a common aetiology for the two diseases. The exact physiopathological mechanisms underlying both FM and IBS onset are unknown. Researchers have investigated many possible causes, including alterations in gut microbiota, which contain billions of microorganisms in the human digestive tract. The gut-brain axis has been proven to be the link between the gut microbiota and the central nervous system, which can then control the gut microbiota composition. In this review, we will discuss the similarities between FM and IBS. Particularly, we will focus our attention on symptomatology overlap between FM and IBS as well as the similarities in microbiota composition between FM and IBS patients. We will also briefly discuss the potential therapeutic approaches based on microbiota manipulations that are successfully used in IBS and could be employed also in FM patients to relieve pain, ameliorate the rehabilitation outcome, psychological distress and intestinal symptoms.

Negative Impact of Disorders of Gut-Brain Interaction on Health-Related Quality of Life: Results From the Rome Foundation Global Epidemiology Survey

BACKGROUND & AIMS

This study used the database from the Rome Foundation Global Epidemiology Survey to assess the differences in quality of life overall, and by age and sex, across individual disorders of gut-brain interaction (DGBI), gastrointestinal anatomical region(s), and number of overlapping DGBI.

METHODS

Data were collected via the Internet in 26 countries, using the Rome IV diagnostic questionnaire and a supplemental questionnaire including the Patient-Reported Outcomes Measurement Information Systems Global-10 quality of life measure. Factorial analyses of variance were used to explore physical and mental quality of life, adjusting for multiple comparisons.

RESULTS

Among the 54,127 respondents, quality of life deteriorated significantly with increasing number of overlapping DGBI, with respondents reporting ≥2 DGBI having significantly poorer quality of life than those with only 1 DGBI or those without any DGBI. Men with DGBI reported better quality of life than women, and those aged ≥65 years reported better quality of life than those <65 years. Age, sex, number of overlapping DGBI, somatization, anxiety, depression, and functional experiences (concern, embarrassment, or stress associated with bowel functioning) relating to DGBI, were significant predictors of poorer physical and mental quality of life.

CONCLUSIONS

This study is the most comprehensive assessment of quality of life to date in adults living with a DGBI. It provides a representative picture of DGBI impact on adults in the global adult population and highlights the significant detrimental impact of living with a DGBI on quality of life.

What Has Longitudinal ‘Omics’ Studies Taught Us about Irritable Bowel Syndrome? A Systematic Review

Irritable bowel syndrome is a prototypical disorder of the brain–gut–microbiome axis, although the underlying pathogenesis and mechanisms remain incompletely understood. With the recent advances in ‘omics’ technologies, studies have attempted to uncover IBS-specific variations in the host–microbiome profile and function. However, no biomarker has been identified to date. Given the high inter-individual and day-to-day variability of the gut microbiota, and a lack of agreement across the large number of microbiome studies, this review focused on omics studies that had sampling at more than one time point. A systematic literature search was performed using various combinations of the search terms “Irritable Bowel Syndrome” and “Omics” in the Medline, EMBASE, and Cochrane Library up to 1 December 2022. A total of 16 original studies were reviewed. These multi-omics studies have implicated Bacteroides, Faecalibacterium prausnitzii, Ruminococcus spp., and Bifidobacteria in IBS and treatment response, found altered metabolite profiles in serum, faecal, or urinary samples taken from IBS patients compared to the healthy controls, and revealed enrichment in the immune and inflammation-related pathways. They also demonstrated the possible therapeutic mechanisms of diet interventions, for example, synbiotics and low fermentable oligosaccharides, disaccharides, monosaccharides, and polyol (FODMAP) diets on microbial metabolites. However, there was significant heterogeneity among the studies and no uniform characteristics of IBS-related gut microbiota. There is a need to further study these putative mechanisms and also ensure that they can be translated to therapeutic benefits for patients with IBS.

Randomised clinical trial: efficacy and safety of the live biotherapeutic product MRx1234 in patients with irritable bowel syndrome

BACKGROUND

MRx1234 is a live biotherapeutic product that contains a strain of Blautia hydrogenotrophica. It is in development for the treatment of irritable bowel syndrome (IBS).

AIMS

To assess the efficacy and safety of MRx1234 in patients with IBS with predominant constipation (IBS-C) or diarrhoea (IBS-D) METHODS: We conducted a multicentre, randomised, double-blind, placebo-controlled, phase 2 trial. Patients aged 18-70 years in two parallel cohorts (IBS-C; IBS-D) were randomised (1:1) to MRx1234 or placebo for 8 weeks. The primary efficacy endpoint was overall responder rate-a composite of improved bowel habit (IBS-C: stool frequency; IBS-D: stool consistency) and abdominal pain intensity-for ≥50% of the treatment period in each cohort. Statistical testing was at a one-sided 0.10 significance level.

RESULTS

Of 366 randomised patients (164 IBS-C; 202 IBS-D), 365 received any study medication (177 MRx1234, 188 placebo). Numerically, although not statistically significantly different, more patients who received MRx1234 than placebo were overall responders in the IBS-C (25.0% vs. 17.1%) and IBS-D (23.4% vs. 17.8%) cohorts. Similar results were observed in the additional combined cohort analysis (24.1% vs. 17.5%; p = 0.063). For the components of the primary endpoint, significantly more patients on MRx1234 than placebo reported improvement in bowel habit in the IBS-C, IBS-D and combined cohorts, while improvements in abdominal pain were observed in each cohort. The safety profile of MRx1234 was similar to placebo.

CONCLUSIONS

MRx1234 has the potential to become a novel, safe treatment option for patients with IBS-C or IBS-D, and for those who have mixed symptoms or transition between subtypes.

CLINICALTRIALS

gov #NCT03721107.

Quality of life in irritable bowel syndrome: Exploring mediating factors through structural equation modelling

BACKGROUND

Irritable Bowel Syndrome (IBS) negatively influences mental and physical quality of life (QoL), but factors that explain this impact are still unclear. Increasing evidence has associated IBS severity, psychological distress, somatic symptoms, and gastrointestinal (GI)-specific anxiety with QoL in IBS. The aim of this study is to further explore these associations and to analyze potential mediating factors.

METHOD

A total of 1017 IBS patients (69.3% female, mean age 40.6 years) who completed a QoL measure (SF-36) were included in this study. A proportion of these participants (N = 183; 72.7% female, mean age 41.7), who additionally completed psychological distress, somatic symptoms, and GI-specific anxiety measures, was included in the mediation analysis. This analysis was conducted via structural equation modelling to identify factors of importance for generic QoL, using a cross-sectional design.

RESULTS

IBS patients reported lower QoL than what is observed in the general population, in particular regarding role limitations caused by health and emotional functioning, vitality, and social functioning. Female patients scored lower than male patients on most QoL dimensions. The effects of IBS severity on mental and physical QoL were mediated by GI-specific anxiety. In addition to GI-specific anxiety, depressive symptoms were also of importance for mental QoL, and somatic symptom severity for physical QoL.

CONCLUSION

QoL is reduced in patients with IBS and GI-specific anxiety, depressive symptoms, and somatic complaints are particularly important for this outcome. Future trials should test the efficacy of psychological interventions specifically targeting these factors in improving QoL in IBS.

Irritable bowel syndrome: current aspects of etiology, pathogenesis, clinic and treatment: A review

Among functional gastrointestinal disorders, Irritable bowel syndrome (IBS) rightfully continues to maintain its leading position. IBS is a kind of standard for understanding the pathogenetic essence of functional diseases of the digestive system, since it is the most common, studied and studied pathology. So, for the query "Irritable Bowel Syndrome" in the electronic database PubMed as of July 30, 2022, 16 599 sources were found, and for the query "Irritable Bowel Syndrome" in the scientific electronic library eLIBRARY.RU 6316. The first part of the review deals with topical aspects of the etiology, pathogenesis and clinical presentation of IBS. The urgency of the problem of IBS is associated with a significant decrease in the quality of life of patients. The review focuses on the role of psycho-emotional disorders, changes localized at the level of the intestinal wall; and a new coronavirus infection COVID-19 in the development of IBS. Abdominal pain as the leading manifestation of IBS is associated primarily with spasm. In this context, antispasmodic drugs can be considered not only as symptomatic agents, but also as pathogenetic therapy for IBS. In the second part of the review, the possibilities of one of the myotropic antispasmodics, mebeverine hydrochloride, in the treatment of IBS are considered in detail.

Associations between Abnormal Eating Styles and Irritable Bowel Syndrome: A Cross-Sectional Study among Medical School Students

(1) Background: Few studies have investigated the association between eating styles and IBS. This study aimed to explore the association between abnormal eating styles and irritable bowel syndrome (IBS). (2) Methods: This cross-sectional study investigated students in China Medical University and Shenyang Medical College. Eating styles were evaluated by the Dutch Eating Behavior Questionnaire (DEBQ), and IBS was diagnosed according to Rome III criteria. Logistic regression was used to estimate odds ratios (ORs) and 95% confidence intervals (CIs). (3) Results: A total of 335 students were diagnosed with IBS. Students with the total scores in tertile 2 and 3 had 1.29 times and 2.75 times higher risk of IBS than students with the total scores in tertile 1, respectively. Simultaneously, the risk of IBS in the tertile 3 of external eating, emotional eating, and restraint eating trends was 3.87 times, 2.71 times, and 3.82 times higher than that of tertile 1, respectively. (4) Conclusions: this study showed that a high score in both total eating styles and each eating style was associated with the odds of having IBS and suggested that the psychological factors behind eating styles may play a critical role in controlling the IBS.

Diet as a therapeutic tool in chronic gastrointestinal disorders: Lessons from the FODMAP journey

BACKGROUND AND AIM

Diet is a powerful tool in the management of gastrointestinal disorders, but developing diet therapies is fraught with challenge. This review discusses key lessons from the FODMAP diet journey.

METHODS

Published literature and clinical experience were reviewed.

RESULTS

Key to designing a varied, nutritionally adequate low-FODMAP diet was our accurate and comprehensive database of FODMAP composition, made universally accessible via our user-friendly, digital application. Our discovery that FODMAPs coexist with gluten in cereal products and subsequent gluten/fructan challenge studies in nonceliac gluten-sensitive populations highlighted issues of collinearity in the nutrient composition of food and confirmation bias in the interpretation of dietary studies. Despite numerous challenges in designing, funding, and executing dietary randomized controlled trials, efficacy of the low-FODMAP diet has been repeatedly demonstrated, and confirmed by real-world experience, giving this therapy credibility in the eyes of clinicians and researchers. Furthermore, real-world application of this diet saw the evolution of a safe and effective three-phased approach. Specialist dietitians must deliver this diet to optimize outcomes as they can target and tailor the therapy and to mitigate the key risks of compromising nutritional adequacy and precipitating disordered eating behaviors, skills outside the gastroenterologist's standard tool kit. While concurrent probiotics are ineffective, specific fiber supplements may improve short-term and long-term outcomes.

CONCLUSIONS

The FODMAP diet is highly effective, but optimal outcomes are contingent on the involvement of a gastroenterological dietitian who can assess, educate, and monitor patients and manage risks associated with implementation of this restrictive diet.

Quality of life and sleep in individuals with irritable bowel syndrome according to different diagnostic criteria and inflammatory bowel diseases: A comparison using data from a population-based survey

BACKGROUND

A proportion of irritable bowel syndrome (IBS) affected patients does not fulfil Rome criteria despite considerable impairment similarly to that in patients with organic gastrointestinal diseases.This investigation aims to examine differences regarding Mental (MQoL), Physical Quality of Life (PQoL), and sleep between IBS according to Rome III (IBS Rome), clinically defined IBS, inflammatory bowel diseases (IBD), and non-IBS/non-IBD individuals.

METHODS

Data from SHIP-Trend (Study of Health in Pomerania, 2008-2012), a population-based cohort study in Germany, were used.

RESULTS

Response was 50.1% (N = 4420). Prevalence was 3.5% for IBS Rome (95% confidence interval (CI): 3.0 - 4.1%, n = 148), 0.6% for clinically defined IBS (CI: 0.4 - 0.9%, n = 27), and 0.8% for IBD (CI: 0.6 - 1.1%, n = 34). Individuals with IBS Rome (4.54 (CI: -5.92; -3.17)) and clinically defined IBS (4.69 (CI: -7.82; -1.56)) had lower scores for MQoL compared to the non-IBS/non-IBD group. PQoL scores were lowered in IBS Rome (6.39 (CI: -7.89; -4.88)) and IBD (5.37 (CI: -8.51; -2.22)), but not in clinically defined IBS compared to the non-IBS/non-IBD group. IBS Rome was the only gastroenterological condition with higher odds of sleeping problems (odds ratio (OR) "falling asleep": 1.74; CI: 1.29; 2.36; OR "remaining asleep": 1.73; CI: 1.26; 2.38).

CONCLUSIONS

IBS Rome is associated with reduced MQoL, PQoL, and sleep problems. Clinically defined IBS is associated only with reduced MQoL. Heterogeneity within IBS affected patients should be considered in clinical routine and screening for daily life impairment should be performed.

Mucosal Gene Transcript Signatures in Treatment Naïve Inflammatory Bowel Disease: A Comparative Analysis of Disease to Symptomatic and Healthy Controls in the European IBD-Character Cohort

Background

Studies of the mucosal transcriptomic landscape have given new insight into the pathogenesis of inflammatory bowel disease (IBD). Recently, the predictive biomarker potential of gene expression signatures has been explored. To further investigate the mucosal gene expression in IBD, we recruited a cohort of treatment naïve patients and compared them to both symptomatic and healthy controls.

Methods

Altogether, 323 subjects were included: Crohn’s disease (N = 75), ulcerative colitis (N = 87) and IBD unclassified (N = 3). Additionally, there were two control groups: symptomatic controls (N = 131) and healthy controls (N = 27). Mucosal biopsies were collected during ileocolonoscopy and gene expression in inflamed and non-inflamed mucosa was explored. Gene expression profiling was performed using Agilent G3 Human Gene Expression 860K v3 One-Color microarray. We recorded information about treatment escalation to anti-TNF agents or surgery, and anti-TNF response, to explore predictive opportunities of the mucosal transcriptome.

Results

Gene expression profiles in symptomatic controls in whom IBD had been excluded resembled that of IBD patients and diverged from that of healthy controls. In non-inflamed Crohn’s disease and ulcerative colitis, gene set enrichment analysis revealed dysregulation of pathways involved in basic cellular biological processes. Mitochondria-associated pathways were dysregulated both in non-inflamed and inflamed Crohn’s disease and ulcerative colitis (>2.6 normalized enrichment scores <−1.8). Gene expression signatures of Crohn’s disease and ulcerative colitis did not predict time for treatment escalation (p = 0.175). No significant association was found between gene expression signatures and anti-TNF response.

Conclusion

Non-inflamed samples are probably superior to inflamed samples when exploring gene expression signatures in IBD and might reveal underlying mechanisms central for disease initiation. The gene expression signatures of the control groups were related to if they were symptomatic or not, which may have important implications for future study designs.

Gut bless you: The microbiota-gut-brain axis in irritable bowel syndrome

Irritable bowel syndrome (IBS) is a common clinical label for medically unexplained gastrointestinal symptoms, recently described as a disturbance of the microbiota-gut-brain axis. Despite decades of research, the pathophysiology of this highly heterogeneous disorder remains elusive. However, a dramatic change in the understanding of the underlying pathophysiological mechanisms surfaced when the importance of gut microbiota protruded the scientific picture. Are we getting any closer to understanding IBS' etiology, or are we drowning in unspecific, conflicting data because we possess limited tools to unravel the cluster of secrets our gut microbiota is concealing? In this comprehensive review we are discussing some of the major important features of IBS and their interaction with gut microbiota, clinical microbiota-altering treatment such as the low FODMAP diet and fecal microbiota transplantation, neuroimaging and methods in microbiota analyses, and current and future challenges with big data analysis in IBS.

AGA Clinical Practice Update on Management of Chronic Gastrointestinal Pain in Disorders of Gut-Brain Interaction: Expert Review

DESCRIPTION

This expert review summarizes approaches to management of pain in disorders of gut-brain interaction. This review focuses specifically on approaches to pain that persist if first-line therapies aimed at addressing visceral causes of pain are unsuccessful. The roles of a therapeutic patient-provider relationship, nonpharmacologic and pharmacologic therapies, and avoidance of opioids are discussed.

METHODS

This was not a formal systematic review but was based on a review of the literature to provide best practice advice statements. No formal rating of the quality of evidence or strength of recommendation was performed. BEST PRACTICE ADVICE 1: Effective management of persistent pain in disorders of gut-brain interaction requires a collaborative, empathic, culturally sensitive, patient-provider relationship. BEST PRACTICE ADVICE 2: Providers should master patient-friendly language about the pathogenesis of pain, leveraging advances in neuroscience and behavioral science. Providers also must understand the psychological contexts in which pain is perpetuated. BEST PRACTICE ADVICE 3: Opioids should not be prescribed for chronic gastrointestinal pain because of a disorder of gut-brain interaction. If patients are referred on opioids, these medications should be prescribed responsibly, via multidisciplinary collaboration, until they can be discontinued. BEST PRACTICE ADVICE 4: Nonpharmacologic therapies should be considered routinely as part of comprehensive pain management, and ideally brought up early on in care. BEST PRACTICE ADVICE 5: Providers should optimize medical therapies that are known to modulate pain and be able to differentiate when gastrointestinal pain is triggered by visceral factors vs centrally mediated factors. BEST PRACTICE ADVICE 6: Providers should familiarize themselves with a few effective neuromodulators, knowing the dosing, side effects, and targets of each and be able to explain to the patient why these drugs are used for the management of persistent pain.

"Association between dietary inflammatory index (DII) and risk of irritable bowel syndrome: a case-control study"

Background

Pathophysiology of IBS is not well recognized; however, several studies have shown the possible relationship between diet and risk of IBS. We assessed the ability of the dietary inflammatory index (DII) to predict the risk of IBS.

Methods

The subjects were 155 IBS cases and 310 age- and sex-matched healthy controls (aged ≥18 years). The participants were recruited from June, 2019 to March, 2020. IBS was recognized using the Rome IV criteria. DII score was computed based on dietary intake using a 168-item FFQ. The DII score was calculated based on energy-adjusted amounts of nutrients using residual method. Logistic regression models were used to estimate multivariable odds ratios (ORs).

Results

The mean DII score was significantly higher among IBS patients in comparison to healthy controls (0.78 ± 2.22 vs. − 0.39 ± 2.27). In crude model, increase in DII as continuous variable was associated with a significant increase in the risk of IBS (OR (95% CI): 1.26 (1.1–15.38)). Furthermore, the association remained significant even after adjusting for age and sex (OR (95% CI): 1.28 (1.1–17.41)) and after multivariate adjustment (OR (95% CI): 1.38 (1.2–1.56)). In crude, age and sex adjusted and multivariate-adjusted models subjects in fourth quartile of DII had higher OR in comparison to subjects in first quartile.

Conclusions

This study showed a possible positive association between a pro-inflammatory diet and the risk of IBS. Thus, encouraging intake of more anti-inflammatory dietary factors and reducing intake of pro-inflammatory factors may be a strategy for reducing risk of IBS.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12937-021-00721-5.

INTERVENTIONS FOR THE TREATMENT OF IRRITABLE BOWEL SYNDROME: A REVIEW OF COCHRANE SYSTEMATIC REVIEWS

BACKGROUND

Irritable bowel syndrome (IBS) is a complex gastrointestinal disorder, whose understanding is relatively uncertain, and the treatment guidance decision still represents a challenge.

OBJECTIVE

To identify and critically appraise systematic reviews (SRs) published in the Cochrane Database of SRs (CDSR) on the effects of interventions (pharmacological and non-pharmacological) for the treatment of IBS.

METHODS

The search was conducted at the Cochrane Library in May 2020. The methodological quality of the SRs was evaluated by the AMSTAR-2 tool.

RESULTS

Eight SRs with moderate to high quality were included, which addressed the treatments: (a) pharmacological: volume agents, antispasmodics, antidepressants and tegaserod; and (b) non-pharmacological: homeopathy, acupuncture, phytotherapy, biofeedback, psychological interventions and hypnotherapy. The results were favorable to antispasmodic drugs and antidepressants regarding the improvement of clinical symptoms. There was no difference between volume agents or tegaserod when compared to placebo. Acupuncture and homeopathy showed a little improvement in symptoms compared to placebo, but the certainty of this evidence was considered low to very low. Psychological interventions seem to improve the overall assessment of the patient and relief symptoms such as abdominal pain. However, there was no long-term follow-up of these patients. The results of the other treatments were considered uncertain due to the high risk of bias.

CONCLUSION

Considering the low quality of the studies included in the SRs, pharmacological treatment with antispasmodics and antidepressants seems to be beneficial for patients with IBS. Among non-pharmacological interventions, psychological interventions seem to be beneficial. However, further clinical trials are recommended with greater methodological rigor to prove these findings.