Anxiety, depression and distress among irritable bowel syndrome and their subtypes: An epidemiological population based study

The impact of depression-mediated gut microbiota composition on Irritable Bowel Syndrome: A Mendelian study

OBJECTIVE

This study uses a two-sample Mendelian randomization (MR) analysis to delineate the causal influence of gut microbiota on the occurrence of irritable bowel syndrome (IBS), concurrently assessing the potential mediating function of depression within this framework.

METHODS

Several two-sample MR methods were used to assess the causal repercussions of gut microbiota on the onset of both IBS and depression. Following this, gut microbiota and depression, which demonstrated notable causal associations, were integrated as exposure variables in a multivariable Mendelian randomization (MVMR) framework to construct a model encompassing gut microbiota, depression, and IBS. Mediation effects were assessed by examining the indirect pathway of gut microbiota → depression → IBS.

RESULTS

Two-sample MR analysis unveiled a statistically significant causal association (P < 0.05) between specific bacterial group within the gut microbiota, notably p_Actinobacteria(OR = 0.829225), c_Clostridia(OR = 0.798897), s_Desulfovibrio_piger(OR = 1.163912), g_Streptococcus(OR = 1.132735), c_Actinobacteria(OR = 0.829224), and the onset of IBS. In the MVMR analysis, the relationship between depression and IBS was significant across Model 3, Model 7, Model 8, and Model 13 (P < 0.05). Assessment of mediation effects revealed that c_Clostridia and o_Clostridiales indirectly impacted IBS through depression, with masking effect ratios of 168.46 % and 168.44 %, respectively.

CONCLUSION

These findings underscore a resilient causal association between the composition of gut microbiota and the initiation of IBS. Furthermore, depression serves as a mediator for particular groups of gut bacteria, thereby contributing to the development of IBS. These observations imply that interventions targeting mental health may potentially alleviate the risk of IBS onset attributable to adverse configurations of gut microbiota.

Gastrointestinal distress, State and Trait anxiety, and dietary intake among college students during the COVID-19 pandemic

OBJECTIVE

This study examined the impact of State and Trait anxiety and dietary intake on college students' gastrointestinal symptoms during the COVID-19 pandemic.

PARTICIPANTS

A total of 455 students, aged 18-23, from two residential colleges in the midwestern United States participated in the study during April 2021.

METHODS

An online questionnaire that included the National Cancer Institute Dietary Screener, State-Trait Inventory for Cognitive and Somatic Anxiety, and an adapted version of the Gastrointestinal Symptoms Questionnaire was used. Stepwise multiple regression analyses and Spearman rho correlation coefficients were used to analyze the data.

RESULTS

High rates of State-somatic, State-cognitive, and Trait-somatic anxiety were present in our study population. These anxiety subscales and dietary intake predicted 26% and 3.8% of the GI symptoms variance, respectively.

CONCLUSION

State-anxiety and Trait-somatic anxiety are large factors in predicting GI symptoms compared to dietary intake. College students could seek anxiety-reducing techniques to ease GI symptoms.

Exploring new subgroups for irritable bowel syndrome using a machine learning algorithm

Irritable bowel syndrome (IBS) is a complicated gut-brain axis disorder that has typically been classified into subgroups based on the major abnormal stool consistency and frequency. The presence of components other than lower gastrointestinal (GI) symptoms, such as psychological burden, has also been observed in IBS manifestations. The purpose of this research is to redefine IBS subgroups based on upper GI symptoms and psychological factors in addition to lower GI symptoms using an unsupervised machine learning algorithm. The clustering of 988 individuals who met the Rome III criteria for diagnosis of IBS was performed using a mixed-type data clustering algorithm. Nine sub-groups emerged from the proposed clustering: (I) High diarrhea, pain, and psychological burden, (II) High upper GI, moderate lower GI, and psychological burden, (III) High psychological burden and moderate overall GI, (IV) High constipation, moderate upper GI, and high psychological burden, (V) moderate constipation and low psychological burden, (VI) High diarrhea and moderate psychological burden, (VII) moderate diarrhea and low psychological burden, (VIII) Low overall GI, and psychological burden, (IX) Moderate lower GI, and low psychological burden. The proposed procedure led to the discovery of new homogeneous clusters in addition to certain well-known Rome sub-types for IBS.

Gut Dysbiosis in Irritable Bowel Syndrome: A Narrative Review on Correlation with Disease Subtypes and Novel Therapeutic Implications

Irritable bowel syndrome (IBS) is a prevalent functional gastrointestinal disorder characterized by chronic abdominal pain and altered bowel habits. It can be subclassified in different subtypes according to the main clinical manifestation: constipation, diarrhea, mixed, and unclassified. Over the past decade, the role of gut microbiota in IBS has garnered significant attention in the scientific community. Emerging research spotlights the intricate involvement of microbiota dysbiosis in IBS pathogenesis. Studies have demonstrated reduced microbial diversity and stability and specific microbial alterations for each disease subgroup. Microbiota-targeted treatments, such as antibiotics, probiotics, prebiotics, synbiotics, fecal microbiota transplantation, and even diet, offer exciting prospects for managing IBS. However, definitive conclusions are hindered by the heterogeneity of these studies. Further research should focus on elucidating the mechanisms, developing microbiome-based diagnostics, and enabling personalized therapies tailored to an individual's microbiome profile. This review takes a deep dive into the microscopic world inhabiting our guts, and its implications for IBS. Our aim is to elucidate the complex interplay between gut microbiota and each IBS subtype, exploring novel microbiota-targeted treatments and providing a comprehensive overview of the current state of knowledge.

The relationship between anxiety and irritable bowel syndrome symptoms among females: A cross-sectional study in Egypt

There is a scarcity of studies focusing on irritable bowel syndrome (IBS) and anxiety in Egypt. Accordingly, our study aimed to assess the association between anxiety and IBS symptomatology among Egyptian females. Three hundred eighty-three females (145 IBS and 238 controls) were included in the study, and data were obtained using structured predesigned questionnaires. IBS and anxiety symptoms were assessed according to the Rome IV criteria and the Arabic version of the beck anxiety inventory, respectively. Both IBS and non-IBS groups showed increased anxiety during the pandemic, without a significant difference between both groups (P value = .657). Higher levels of education were significantly associated with severe anxiety (P value = .031). Multivariate analysis of IBS patients showed that intermediate education was significantly associated with 75% lower odds for increased IBS symptoms compared with illiterate or read-and-write IBS patients [odds ratio (OR): 0.25, 95% confidence interval (CI) 0.06-0.95, P value = .042]. Urban residence was significantly associated with 13.5 times greater odds of increased IBS symptoms, compared with rural residence (OR: 13.48, 95% CI 3.55-51.25, P value < .001). Moreover, patients who lost their job during the pandemic were 12.9 times more likely to have increased symptoms (OR: 12.89, 95% CI 1.84-90.15, P value = 0.01). A unit increase in patients age and beck anxiety inventory score was associated with 68% and 75% greater odds for increased IBS symptoms, respectively (OR: 1.68, 95% CI 1.12-2.53, P value = .012; OR: 1.75, 95% CI 1.08-2.84, P value = .024). Increasing anxiety is associated with increased IBS symptoms. Therefore, IBS patients should be screened for anxiety, and the role of psychiatric management of anxiety in the amelioration of IBS symptoms must be explored.

Irritable Bowel Syndrome and the Gut Microbiome: A Comprehensive Review

Irritable Bowel Syndrome (IBS) is a functional disorder of the gastrointestinal tract characterized by abdominal pain and altered bowel habits. It has a prevalence of 10 to 25% in the United States and has a high disease burden, as evidenced by reduced quality of life, decreased work productivity and increased healthcare utilization and costs. IBS has been associated with several intra-intestinal and extra-intestinal conditions, including psychiatric comorbidities. Although the pathophysiology of IBS has not been fully elucidated, it involves dysregulation of communication between the brain and gut (brain–gut axis) which is associated with alterations in intestinal motility, gut permeability, visceral hypersensitivity and gut microbiota composition. The purpose of this article is to review the role the gut microbiota plays in the pathophysiology of IBS, understand factors that affect the gut microbiome and explore the microbiome as a target of treatment.

Meranzin Hydrate Improves Depression-Like Behaviors and Hypomotility via Ghrelin and Neurocircuitry

OBJECTIVE

To investigate whether meranzin hydrate (MH) can alleviate depression-like behavior and hypomotility similar to Chaihu Shugan Powder (CSP), and further explore the potential common mechanisms.

METHODS

Totally 120 Spraque-Dawley rats were randomly divided into 5-8 groups including sham, vehicle, fluoxetine (20 mg/kg), mosapride (10 mg/kg), CSP (30 g/kg), MH (9.18 mg/kg), [D-Lys3]-GHRP-6 (Dlys, 0.5 mg/kg), and MH+Dlys groups by a random number table, 8 rats in each group. And 32 mice were randomly divided into wild-type, MH (18 mg/kg), growth hormone secretagogue receptor-knockout (GHSR-KO), and GHSR+MH groups, 8 mice in each group. The forced swimming test (FST), open field test (OFT), tail suspension test (TST), gastric emptying (GE) test, and intestinal transit (IT) test were used to assess antidepressant and prokinetic (AP) effects after drug single administration for 30 min with absorbable identification in rats and mice, respectively. The protein expression levels of brain-derived neurotrophic factor (BDNF) and phosphorylated mammalian target of rapamycin (p-mTOR) in the hippocampus of rats were evaluated by Western blot. The differences in functional brain changes were determined via 7.0 T functional magnetic resonance imaging-blood oxygen level-dependent (fMRI-BOLD).

RESULTS

MH treatment improved depression-like behavior (FST, OFT) and hypomotility (GE, IT) in the acute forced swimming (FS) rats (all P<0.05), and the effects are similar to the parent formula CSP. The ghrelin antagonist [D-Lys3]-GHRP-6 inhibited the effect of MH on FST and GE (P<0.05). Similarly, MH treatment also alleviated depression-like behavior (FST, TST) in the wild-type mice, however, no effects were found in the GHSR KO mice. Additionally, administration of MH significantly stimulated BDNF and p-mTOR protein expressions in the hippocampus (both P<0.01), which were also prevented by [D-Lys3]-GHRP-6 (P<0.01). Besides, 3 main BOLD foci following acute FS rats implicated activity in hippocampus-thalamus-basal ganglia (HTB) circuits. The [D-Lys3]-GHRP-6 synchronously inhibited BOLD HTB foci. As expected, prokinetic mosapride only had effects on the thalamus and basal ganglia, but not on the hippocampus. Within the HTB, the hippocampus is implicated in depression and FD.

CONCLUSIONS

MH accounts for part of AP effects of parent formula CSP in acute FS rats, mainly via ghrelin-related shared regulation coupled to BOLD signals in brain areas. This novel functionally connection of HTB following acute stress, treatment, and regulation highlights anti-depression unified theory.

Omeprazole treatment manifests anxiolytic effects in a cysteamine hydrochloride induced mouse model of gastrointestinal disorder

Omeprazole, a proton pump inhibitor (PPI), has widely been used to treat various gastrointestinal (GI) disorders. Notably, many clinical symptoms of GI disorders have been known to be associated with anxiety. In recent years, an exponentially increased number of subjects with abnormal ageing, neurological deficits, and psychiatric problems simultaneously exhibit GI dysfunctions as well as anxiety. Considering the fact, drugs that are used to treat GI disorders can be speculated to mitigate anxiety-related symptoms, and vice versa. Although, omeprazole treatment has been reported to result in development of anxiety and neurocognitive decline, ample reports suggest that omeprazole treatment is beneficial for the positive regulation of neuroplasticity. While underlying mechanisms of omeprazole-mediated neurological alterations remain obscure, the available scientific data on the omeprazole induced adverse effects in the brain appear to be inadequate, uncertain, and controversial. Hence, this study revisited the effect of omeprazole treatment on the degree of anxiety-like behaviours in a cysteamine hydrochloride (HCl) induced mouse model of GI disorder using open field test (OFT), light-dark box (LDB) test and elevated plus maze (EPM). Results revealed that omeprazole treatment mitigates anxiety-related behaviours in the cysteamine HCl induced animal model of GI disorder. Thus, this study assuredly supports and validates the anxiolytic properties of omeprazole. However, the adverse effects associated with inappropriate intake of omeprazole may not completely be excluded. Therefore, this study advocates the future direction in determining the long-term effects of omeprazole on the brain functions.

Irritable Bowel Syndrome, Depression, and Neurodegeneration: A Bidirectional Communication from Gut to Brain

Patients with irritable bowel syndrome (IBS) are increasingly presenting with a wide range of neuropsychiatric symptoms, such as deterioration in gastroenteric physiology, including visceral hypersensitivity, altered intestinal membrane permeability, and gastrointestinal motor dysfunction. Functional imaging of IBS patients has revealed several abnormalities in various brain regions, such as significant activation of amygdala, thinning of insular and anterior cingulate cortex, and increase in hypothalamic gray matter, which results in poor psychiatric and cognitive outcomes. Interrelations between the enteric and central events in IBS-related gastrointestinal, neurological, and psychiatric pathologies have compelled researchers to study the gut-brain axis-a bidirectional communication that maintains the homeostasis of the gastrointestinal and central nervous system with gut microbiota as the protagonist. Thus, it can be disrupted by any alteration owing to the gut dysbiosis or loss of diversity in microbial composition. Available evidence indicates that the use of probiotics as a part of a balanced diet is effective in the management of IBS and IBS-associated neurodegenerative and psychiatric comorbidities. In this review, we delineate the pathogenesis and complications of IBS from gastrointestinal and neuropsychiatric standpoints while also discussing the neurodegenerative events in enteric and central nervous systems of IBS patients and the therapeutic potential of gut microbiota-based therapy established on clinical and preclinical data.

Peripheral Guanylate Cyclase-C modulation of corticolimbic activation and corticotropin-releasing factor signaling in a rat model of stress-induced colonic hypersensitivity

BACKGROUND

Psychological stress is a risk factor for irritable bowel syndrome, a functional gastrointestinal pain disorder featuring abnormal brain-gut connectivity. The guanylate cyclase-C (GC-C) agonist linaclotide has been shown to relieve abdominal pain in IBS-C and exhibits antinociceptive effects in rodent models of post-inflammatory visceral hypersensitivity. However, the role GC-C signaling plays in psychological stress-induced visceral hypersensitivity is unknown. Here, we test the hypothesis that GC-C agonism reverses stress-induced colonic hypersensitivity via inhibition of nociceptive afferent signaling resulting in normalization of stress-altered corticotropin-releasing factor (CRF) expression in brain regions involved in pain perception and modulation.

METHODS

Adult female rats were exposed to water avoidance stress or sham stress for 10 days, and the effects of linaclotide on stress-induced changes in colonic sensitivity, corticolimbic phospho-extracellular signal-regulated kinase (pERK), and CRF expression were measured using a combination of behavioral assessments, immunohistochemistry, and qRT-PCR.

KEY RESULTS

Stressed rats exhibited colonic hypersensitivity and elevated corticolimbic pERK on day 11, which was inhibited by linaclotide. qRT-PCR analysis revealed dysregulated CRF expression in the medial prefrontal cortex, paraventricular nucleus of the hypothalamus, and central nucleus of the amygdala on day 28. Dysregulated CRF expression was not affected by linaclotide treatment.

CONCLUSIONS AND INFERENCES

Our results demonstrate that exposure to repeated stress induces chronic colonic hypersensitivity in conjunction with altered corticolimbic activation and CRF expression. GC-C agonism attenuated stress-induced colonic hypersensitivity and ERK phosphorylation, but had no effect on CRF expression, suggesting the analgesic effects of linaclotide occur independent of stress-driven CRF gene expression in corticolimbic circuitry.

Symptom-network dynamics in irritable bowel syndrome with comorbid panic disorder using electronic momentary assessment: A randomized controlled trial of escitalopram vs. placebo

INTRODUCTION

Momentary ecological assessment indicated alleviated abdominal pain in escitalopram treatment of irritable bowel syndrome (IBS) with comorbid panic disorder. Hitherto, little is known about symptom formation, i.e., how psychological impact physical symptoms, and vice versa, and about the effect of SSRI-treatment on symptom formation.

OBJECTIVE

To investigate how psychological and somatic symptoms co-vary over time in IBS patients with comorbid panic disorder and how they are affected by escitalopram treatment.

METHODS

Experience sampling data from 14 IBS patients with panic disorder were obtained from a single-centre, double-blind, parallel-group, randomized controlled trial on escitalopram versus placebo. At baseline, after three and six months, multilevel time-lagged linear regression analysis was used to construct symptom networks. Network connections represented coefficients between various affect and gastrointestinal items.

RESULTS

Connectivity increased up to 3 months in both groups. Between 3 and 6 months, connectivity decreased for placebo and further increased in the escitalopram group. Additionally, a steep increase in node strength for negative affect nodes was observed in the escitalopram network and the opposite for positive affect nodes. Over time, group symptom networks became increasingly different from each other. Anxious-anxious and enthusiastic-relaxed became significantly different between groups at 6 months. The connection that changed significantly in all analyses was anxious-anxious.

CONCLUSIONS

Escitalopram treatment was associated with changes in the symptom networks in IBS patients with panic disorder. While mood and physical symptoms improve over time, mainly connectivity between mood nodes changed, possibly pointing towards a healthier emotion regulation resulting in alleviation of physical symptoms.

Importance of Non-pharmacological Approaches for Treating Irritable Bowel Syndrome: Mechanisms and Clinical Relevance

Chronic visceral pain represents a major unmet clinical need with the severity of pain ranging from mild to so severe as to prevent individuals from participating in day-to-day activities and detrimentally affecting their quality of life. Although chronic visceral pain can be multifactorial with many different biological and psychological systems contributing to the onset and severity of symptoms, one of the major triggers for visceral pain is the exposure to emotional and physical stress. Chronic visceral pain that is worsened by stress is a hallmark feature of functional gastrointestinal disorders such as irritable bowel syndrome (IBS). Current pharmacological interventions for patients with chronic visceral pain generally lack efficacy and many are fraught with unwanted side effects. Cognitive behavioral therapy (CBT) has emerged as a psychotherapy that shows efficacy at ameliorating stress-induced chronic visceral pain; however, the molecular mechanisms underlying CBT remain incompletely understood. Preclinical studies in experimental models of stress-induced visceral pain employing environmental enrichment (EE) as an animal model surrogate for CBT are unraveling the mechanism by which environmental signals can lead to long-lasting changes in gene expression and behavior. Evidence suggests that EE signaling interacts with stress and nociceptive signaling. This review will (1) critically evaluate the behavioral and molecular changes that lead to chronic pain in IBS, (2) summarize the pharmacological and non-pharmacological approaches used to treat IBS patients, and (3) provide experimental evidence supporting the potential mechanisms by which CBT ameliorates stress-induced visceral pain.

Behavioral and Diet Therapies in Integrated Care for Patients With Irritable Bowel Syndrome

Irritable bowel syndrome (IBS) is a common, symptom-based condition that has negative effects on quality of life and costs health care systems billions of dollars each year. Until recently, management of IBS has focused on over-the-counter and prescription medications that reduce symptoms in fewer than one-half of patients. Patients have increasingly sought natural solutions for their IBS symptoms. However, behavioral techniques and dietary modifications can be effective in treatment of IBS. Behavioral interventions include gastrointestinal-focused cognitive behavioral therapy and gut-directed hypnotherapy to modify interactions between the gut and the brain. In this pathway, benign sensations from the gut induce maladaptive cognitive or affective processes that amplify symptom perception. Symptoms occur in response to cognitive and affective factors that trigger fear of symptoms or lack of acceptance of disease, or from stressors in the external environment. Among the many dietary interventions used to treat patients with IBS, a diet low in fermentable oligosaccharides, disaccharides, monosaccharides, and polyols is the most commonly recommended by health care providers and has the most evidence for efficacy. Patient with IBS who choose to follow a diet low in fermentable oligosaccharides, disaccharides, monosaccharides, and polyols should be aware of its 3 phases: restriction, reintroduction, and personalization. Management of IBS should include an integrated care model in which behavioral interventions, dietary modification, and medications are considered as equal partners. This approach offers the greatest likelihood for success in management of patients with IBS.

Bladder overactivity induced by psychological stress in female mice is associated with enhanced bladder contractility

AIMS

To investigates the effects of water avoidance stress on voiding behaviour and functional bladder responses in mice.

MAIN METHODS

Mice in the Stress group were exposed to water avoidance stress (WAS) for 1 h/day for 10 days, Controls were age-matched and housed normally. Voiding behaviour was measured periodically throughout the stress protocol and bladders were isolated 24-h after final stress exposure to measure bladder compliance, spontaneous phasic activity, contractile responses, and release of urothelial mediators.

KEY FINDINGS

Repeated stress exposure induced a significant increase in plasma corticosterone levels in the WAS group compared to control. An overactive bladder phenotype was observed in WAS mice, causing a significant increase in the number of voiding events observed from as early as day-3, and a 7-fold increase following 10-days' stress. This increase in voiding frequency was associated with a significant decrease in void size, an increase in the number of small voids, but no change in total voided volume. Bladders from stressed mice showed a significant increase in the maximum responses to the muscarinic agonist carbachol (p < 0.01), in addition to enhanced pressure responses to the purinergic agonists ATP (p < 0.05) and αβ-mATP (p < 0.05), and non-receptor mediated contractions to KCl (p < 0.05) compared to controls. Nerve-mediated bladder contractions to electric field stimulation were not significantly affected by stress, nor were spontaneous phasic contractions or release of urothelial ATP and acetylcholine.

SIGNIFICANCE

Repeated exposure to water avoidance stress produced an overactive bladder phenotype, confirmed by increased voiding frequency, and associated with enhanced bladder contractile responses.

Associations among neurophysiology measures in irritable bowel syndrome (IBS) and their relevance for IBS symptoms

Abnormal gut-brain interactions are common in irritable bowel syndrome (IBS), but the associations between neurophysiological measures and their relation to gastrointestinal (GI) symptoms are poorly understood. Our aim was to explore these relationships and define the most relevant neurophysiology measures for GI symptom severity in IBS. IBS patients underwent small intestinal motility (manometry; fasted and fed contraction frequency, phase III time) and secretion (transmural potential difference), rectal sensorimotor (barostat; sensory thresholds, tone response, compliance), autonomic nervous system (baroreceptor sensitivity and effectiveness), and colonic motor function (transit time) examinations. GI symptom severity (GSRS-IBS), and anxiety and depression (HAD) as a proxy measure of central nervous system (CNS) dysfunction, were assessed. In total 281 IBS patients (Rome II criteria) were included (74% females, median age 36 [interquartile range 28-50] years). Significant correlations between neurophysiology measures were stronger within, rather than between, different neurophysiological examinations. The strongest neurophysiology-symptom correlations occurred between a combination of CNS and visceral sensitivity parameters, and GSRS-IBS total score and pain domain (ρ = 0.40, p < 0.001, and ρ = 0.38, p < 0.001). Associations between GI symptoms in IBS and individual and combinations of neurophysiological factors occurred, primarily in CNS and visceral sensitivity measures, providing new insights into the clinical presentation of IBS.

Irritable Bowel Syndrome and Neurological Deficiencies: Is There A Relationship? The Possible Relevance of the Oxidative Stress Status

Background: Irritable bowel syndrome (IBS) is one of the most common functional gastrointestinal disorders, exhibiting complex and controversial pathological features. Both oxidative stress and inflammation-related reactive oxygen species production may be involved in IBS pathological development. Thus, we focused on several aspects regarding the causes of oxidative stress occurrence in IBS. Additionally, in the molecular context of oxidative changes, we tried to discuss these possible neurological implications in IBS. Methods: The literature search included the main available databases (e.g., ScienceDirect, Pubmed/Medline, Embase, and Google Scholar). Articles in the English language were taken into consideration. Our screening was conducted based on several words such as “irritable bowel syndrome”, “gut brain axis”, “oxidative stress”, “neuroendocrine”, and combinations. Results: While no consistent evidence suggests clear pathway mechanisms, it seems that the inflammatory response may also be relevant in IBS. The mild implication of oxidative stress in IBS has been described through clinical studies and some animal models, revealing changes in the main markers such as antioxidant status and peroxidation markers. Moreover, it seems that the neurological structures involved in the brain-gut axis may be affected in IBS rather than the local gut tissue and functionality. Due to a gut-brain axis bidirectional communication error, a correlation between neurological impairment, emotional over-responsiveness, mild inflammatory patterns, and oxidative stress can be suggested. Conclusions: Therefore, there is a possible correlation between neurological impairment, emotional over-responsiveness, mild inflammatory patterns, and oxidative stress that are not followed by tissue destruction in IBS patients. Moreover, it is not yet clear whether oxidative stress, inflammation, or neurological impairments are key determinants or in which way these three interact in IBS pathology. However, the conditions in which oxidative imbalances occur may be an interesting research lead in order to find possible explanations for IBS development.

What impact do Rome IV criteria have on patients with IBS in China?

Background: The Rome criteria for functional gastrointestinal diseases (FGIDs) have been updated from Rome III to Rome IV. This study aimed to investigate the impact of the update on patients with irritable bowel syndrome (IBS) in China.Methods: A previous database including consecutive patients with FGIDs (according to Rome III criteria) from gastrointestinal department of a tertiary hospital in China was re-analyzed. Demographic information, clinical symptoms, psychological status (Zung self-rating scale), and sleep quality (Pittsburgh sleep quality index) were compared between patients with Rome III and Rome IV IBS.Results: Of the 946 patients with FGIDs, only 58 (6.1%) were diagnosed with Rome IV IBS [less than 292 (30.9%) under Rome III criteria] with a surge of the number of unspecified functional bowel disorders (U-FBD). All patients with IBS were divided into three groups: group A [meeting both Rome III and IV criteria, accounting for 43 (4.6%) of patients with FGIDs], group B [meeting only Rome III criteria, 249 (26.3%)], and group C [meeting only Rome IV criteria,15 (1.6%)]. Significant differences in frequency and severity of symptoms, subtypes, and sleep quality among groups (all p < .05) were found. Patients with Rome III IBS having sleep disorder tended to be more serious than those without. On the contrary, it was not the case under Rome IV criteria.Conclusions: Number of IBS patients was greatly reduced accompanied by a surge in U-FBD. Besides, the updated criteria also had great impacts on clinical parameters, sleep quality and psychological state of IBS patients.HighlightsRome IV criteria removed the description of abdominal discomfort for IBS.The updated Rome criteria had great impacts on IBS patients in our database.Our study analyzed the characteristics of IBS patients who fulfilled both criteria.Alterations in the Rome criteria also led to changes in the disease spectrum of FBD.

A Framework for Understanding the Role of Psychological Processes in Disease Development, Maintenance, and Treatment: The 3P-Disease Model

Health psychology is multidisciplinary, with researchers, practitioners, and policy makers finding themselves needing at least some level of competency in a variety of areas from psychology to physiology, public health, and others. Given this multidisciplinary ontology, prior attempts have been made to establish a framework for understanding the role of biological, psychological, and socio-environmental constructs in disease development, maintenance, and treatment. Other models, however, do not explain how factors may interact and develop over time. The aim here was to apply and adapt the 3P model, originally developed and used in the treatment of insomnia, to couch the biopsychosocial model in a way that explains how diseases develop, are maintained, and can be treated. This paper outlines the role of predisposing, precipitating, and perpetuating factors in disease states and conditions (the 3Ps) and provides examples of how this model may be adapted and applied to a number of health-related diseases or disorders including chronic pain, gastrointestinal disorders, oral disease, and heart disease. The 3P framework can aid in facilitating a multidisciplinary, theoretical approach and way of conceptualizing the study and treatment of diseases in the future.

Association Between Repeated Episodes of Gastroenteritis and Mental Health Problems in Childhood and Adolescence

OBJECTIVE

The Avon Longitudinal Study of Parents and Children (ALSPAC) and Maternal Adversity, Vulnerability and Neurodevelopment (MAVAN) cohorts were used to determine whether repeated exposure to gastroenteritis in early life could predict risk for psychiatric problems in childhood and in ALSPAC adolescents. We determined whether inflammatory biomarkers moderated the association between repeated gastroenteritis and mental health in adolescents from ALSPAC.

METHOD

Episodes of gastroenteritis from birth to 30 and 36 months were reported by mothers. Psychological problems were assessed using the total difficulties and subscale scores on the Revised Rutter Parent Scale for Preschool Children at 42 months and the Strengths and Difficulties Questionnaire (SDQ) at 81 months in ALSPAC. Presence of psychiatric disorders at 15.5 years was assessed using the Development and Well-Being Assessment (DAWBA) in ALSPAC. In the MAVAN replication cohort, total difficulties were assessed on the SDQ at 60 and 72 months. Serum interleukin-6 (IL-6) and C-reactive protein (CRP) at 9.5 years and CRP at 15.5 years were measured in ALSPAC participants.

RESULTS

Repeated gastroenteritis associated with the total difficulties score in ALSPAC and MAVAN children. The β values were small, indicating that the clinical relevance of these findings requires further investigation. Repeated gastroenteritis was significantly associated with an increased prevalence of externalizing disorders at age 15.5 years, but odds ratios were small. CRP or IL-6 at 9.5 years or CRP at 15.5 years did not significantly moderate the association between repeated gastroenteritis and prevalence of psychiatric disorders.

CONCLUSION

Identifying factors associated with vulnerability to psychopathology is key to early identification of individuals at risk.

The role of the brain-gut-microbiota axis in psychology: The importance of considering gut microbiota in the development, perpetuation, and treatment of psychological disorders

INTRODUCTION

The prevalence of psychological disorders remains stable despite steady increases in pharmacological treatments suggesting the need for auxiliary treatment options. Consideration of the brain-gut-microbiota axis (BGMA) has made inroads into reconceptualizing psychological illness from a more holistic perspective. While our understanding of the precise role of gut microbiota (GM) in psychological illness is in its infancy, it represents an attractive target for novel interventions.

METHOD

An extensive review of relevant literature was undertaken.

RESULTS

Gut microbiota are proposed to directly and indirectly influence mood, cognition, and behavior which are key components of mental health. This paper outlines how GM may be implicated in psychological disorders from etiology through to treatment and prevention using the Four P model of case formulation.

CONCLUSION

Moving forward, integration of GM into the conceptualization and treatment of psychological illness will require the discipline of psychology to undergo a significant paradigm shift. While the importance of the GM in psychological well-being must be respected, it is not proposed to be a panacea, but instead, an additional arm to a multidisciplinary approach to treatment and prevention.

Symptom-based latent classes of persons with irritable bowel syndrome

A large amount of interindividual variability exists in symptom experiences of persons with irritable bowel syndrome (IBS). Thus, consideration of multiple symptoms to identify distinct symptom subgroups may be useful in directing personalized health strategies for symptom management. We aimed to identify latent classes (i.e., subgroups) of persons with IBS who share similar patterns of symptoms using symptom-related variables (six groups of daily diary symptoms, cognitive beliefs about IBS, and IBS quality of life [QOL]); and to examine how subgroups differed in patient characteristics. Data were derived from a baseline assessment of men and women enrolled in two cognitively-focused intervention trials (N = 332). Using latent class analysis, four latent classes were identified: Class 1 (low symptoms and good QOL, n = 153), Class 2 (low symptoms and moderate QOL, n = 106), Class 3 (high symptoms with diarrhea and poor QOL, n = 38), and Class 4 (high symptoms with low diarrhea and moderate QOL, n = 35). Diarrhea, being female, less formal education, unemployment, and previous history of major depressive disorder were associated with membership in Class 3. Using these distinct symptom profiles, the next step is to explore underlying mechanisms accounting for symptom burden with the goal of designing tailored interventions to reduce that burden.

Anxiety and depression in irritable bowel syndrome: Exploring the interaction with other symptoms and pathophysiology using multivariate analyses

BACKGROUND

Anxiety or depression, in other words, psychological distress, are common comorbidities in patients with irritable bowel syndrome (IBS), but their interaction with pathophysiological factors and other symptoms are unclear.

METHODS

Patients with IBS (Rome III criteria), thoroughly characterized regarding pathophysiology (colonic transit time, visceral sensitivity, and autonomic nervous system [ANS] function), symptom profile (IBS severity, somatic symptoms, gastrointestinal [GI]-specific anxiety and fatigue), and quality of life, were explored for differences regarding pathophysiology and symptoms between patients with and without reported psychological distress in univariate and multivariate analyses (Principal Component Analysis [PCA] with Hotelling's T² and Orthogonal Partial Least Squares-Discriminant Analysis [OPLS-DA]).

KEY RESULTS

When using Hospital Anxiety and Depression Scale score ≥8 as cut-off score, including both borderline and clinically significant cases, 345 (44.9%) out of 769 IBS patients reported anxiety, and 198 (25.7%) depression. In univariate analyses, patients reporting psychological distress demonstrated more severe GI and non-GI symptoms, fatigue, GI-specific anxiety and lower quality of life, and differences for some pathophysiological measures. IBS patients with and without reported psychological distress showed significant differences between the multivariate means in symptom reporting (PCA; both P < 0.001), and in pathophysiological measures in patients with and without anxiety (P = 0.018). Visceral hypersensitivity, altered ANS function, more severe GI-specific anxiety, fatigue, and higher somatic non-GI symptoms were the factors that most strongly separated patients with and without psychological distress (OPLS-DA).

CONCLUSIONS AND INFERENCES

Reported anxiety and depression are common in IBS patients, and our study demonstrates that they are interwoven in the complex pathophysiological and clinical picture of IBS.

Relief of irritable bowel syndrome by fecal microbiota transplantation is associated with changes in diversity and composition of the gut microbiota

OBJECTIVE

To evaluate the efficacy and safety of fecal microbiota transplantation (FMT) for refractory irritable bowel syndrome (IBS).

METHODS

Microbiota suspensions from feces of the donors were injected into the intestines of 30 Chinese patients with refractory IBS. Microbiota composition analysis and genomic DNA extraction of fecal samples obtained from these patients at baseline and 1 month after FMT were performed. Clinical efficacy and safety of FMT were assessed using questionnaires covering four aspects of IBS therapeutic efficacy and assessment of adverse effects during a 6-month follow-up.

RESULTS

FMT improved IBS gastrointestinal symptoms and alleviated depression and anxiety, as shown by the improved IBS-QOL, IBS-SSS, GSRS, HAMA and HAMD scores at 1 month and 3 months after FMT. A total adverse event rate of FMT was 6.7% (2/30). Gut microbiota analysis revealed that FMT responders had a significantly higher Shannon diversity index before FMT than non-responders. In addition, analysis of differences in bacterial composition before and after FMT in responders showed specific abundance of the phyla Verrucomincrobia and Euryarchaeota at 1 month after FMT. At the genus level, Methanobrevibacter and Akkermansia were the most abundant fecal microbiota 1 month after FMT compared with those before FMT.

CONCLUSIONS

FMT may be an effective and safe therapeutic strategy for treating IBS that achieves a sustained clinical response 3-6 months after the first procedure. Changes in the diversity and dominant flora may contribute to its therapeutic effect.

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

BACKGROUND

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

AIM

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

RESULTS

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

CONCLUSION

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

Helicobacter pylori Vacuolating Cytotoxin A Causes Anorexia and Anxiety via Hypothalamic Urocortin 1 in Mice

Helicobacter pylori (Hp) infection is related to the pathogenesis of chronic gastric disorders and extragastric diseases. Here, we examined the anorexigenic and anxiogenic effects of Hp vacuolating cytotoxin A (VacA) through activation of hypothalamic urocortin1 (Ucn1). VacA was detected in the hypothalamus after peripheral administration and increased Ucn1 mRNA expression and c-Fos-positive cells in the hypothalamus but not in the nucleus tractus solitarius. c-Fos and Ucn1-double positive cells were detected. CRF1 and CRF2 receptor antagonists suppressed VacA-induced anxiety and anorexia, respectively. VacA activated single paraventricular nucleus neurons and A7r5 cells; this activation was inhibited by phospholipase C (PLC) and protein kinase C (PKC) inhibitors. VacA causes anorexia and anxiety through the intracellular PLC-PKC pathway, migrates across the blood-brain barrier, and activates the Ucn1-CRF receptor axis.

Visceral Pain

Most of us live blissfully unaware of the orchestrated function that our internal organs conduct. When this peace is interrupted, it is often by routine sensations of hunger and urge. However, for >20% of the global population, chronic visceral pain is an unpleasant and often excruciating reminder of the existence of our internal organs. In many cases, there is no obvious underlying pathological cause of the pain. Accordingly, chronic visceral pain is debilitating, reduces the quality of life of sufferers, and has large concomitant socioeconomic costs. In this review, we highlight key mechanisms underlying chronic abdominal and pelvic pain associated with functional and inflammatory disorders of the gastrointestinal and urinary tracts. This includes how the colon and bladder are innervated by specialized subclasses of spinal afferents, how these afferents become sensitized in highly dynamic signaling environments, and the subsequent development of neuroplasticity within visceral pain pathways. We also highlight key contributing factors, including alterations in commensal bacteria, altered mucosal permeability, epithelial interactions with afferent nerves, alterations in immune or stress responses, and cross talk between these two adjacent organs.

Perceived Stress, Its Physiological Correlates, and Quality of Life in Patients With Irritable Bowel Syndrome

Irritable bowel syndrome (IBS) is a chronic, common disorder of the gastrointestinal tract associated with high psychological comorbidity and diminished quality of life. Patients with IBS display a heightened sensitivity to stress, although the literature is inconsistent as to whether they have a dysregulated stress response. The purpose of the present investigation, a substudy of a larger research effort, was to examine physiological correlates of perceived stress in patients with IBS (cortisol and adrenocorticotropic hormone) and to explore associations between perceived stress and quality of life. A total of 101 participants (35 with IBS [predominant subtypes IBS-constipation and IBS-diarrhea] and 66 healthy controls [HCs]) completed self-report inventories regarding perceived stress and quality of life, and fasting peripheral blood was drawn. Participants with IBS did not differ from the HC in demographic or physiological measures but did differ in psychological measures, reporting significantly higher levels of perceived stress and lower levels of quality of life. Perceived stress and quality of life were not significantly associated in IBS participants. However, differential findings of the stress response were found within IBS participants by sex, race, and subtype. These findings illustrate the heterogeneity of the IBS patient population, underscore the necessity of evaluating larger sample sizes and increasing the diversity of such samples to include males and ethnic minorities, and demonstrate the importance of taking an individualized approach to evaluation and treatment in the IBS patient population.

Connecting Our Gut Feeling and How Our Gut Feels: The Role of Well-being Attributes in Irritable Bowel Syndrome

Background/Aims

There is a close relationship between the mind and gut in the pathogenesis of functional bowel disorders. Common psychological disturbances such as depression and anxiety are not uncommon in those with irritable bowel syndrome (IBS). There is little research investigating the role of positive psychology and gastrointestinal (GI) conditions. In this pilot study we investigated the well-being attributes in those with and without IBS.

Methods

We used an anonymous online survey and recruited 416 study subjects using social media as the main method of recruitment. We gathered demographic information, GI symptoms, history of mental health issues such as anxiety and depression, assessed several well-being attributes, and finally assessed subjective well-being. We hypothesized that those with GI symptoms and IBS have lower scores in their well-being attributes compared to healthy controls.

Results

We observed that a history of anxiety and depression is significantly associated with GI symptoms and IBS. In addition, sense of subjective well-being and several well-being attributes are negatively associated with GI symptoms and/or IBS. Of interest, the household income showed a negative correlation with the prevalence of GI symptoms and IBS.

Conclusions

Subjective well-being, and several well-being attributes that contribute to the sense of overall contentment, are negatively associated with GI symptoms and IBS. The link between subjective well-being, and GI symptoms and IBS are independent of anxiety and depression. Well-being attributes and sense of subjective well-being may be a contributory factor in clinical expression of GI symptoms or IBS consistent with the biopsychosocial model of the disease.

Mechanisms of Stress-induced Visceral Pain

Evidence suggests that long-term stress facilitates visceral pain through sensitization of pain pathways and promotes chronic visceral pain disorders such as the irritable bowel syndrome (IBS). This review will describe the importance of stress in exacerbating IBS-induced abdominal pain. Additionally, we will briefly review our understanding of the activation of the hypothalamic-pituitary-adrenal axis by both chronic adult stress and following early life stress in the pathogenesis of IBS. The review will focus on the glucocorticoid receptor and corticotropin-releasing hormone-mediated mechanisms in the amygdala involved in stress-induced visceral hypersensitivity. One potential mechanism underlying persistent effects of stress on visceral sensitivity could be epigenetic modulation of gene expression. While there are relatively few studies examining epigenetically mediated mechanisms involved in stress-induced visceral nociception, alterations in DNA methylation and histone acetylation patterns within the brain, have been linked to alterations in nociceptive signaling via increased expression of pro-nociceptive neurotransmitters. This review will discuss the latest studies investigating the long-term effects of stress on visceral sensitivity. Additionally, we will critically review the importance of experimental models of adult stress and early life stress in enhancing our understanding of the basic molecular mechanisms of nociceptive processing.

The Increased Level of Depression and Anxiety in Irritable Bowel Syndrome Patients Compared with Healthy Controls: Systematic Review and Meta-analysis

BACKGROUND/AIMS

Irritable bowel syndrome (IBS) patients commonly experience psychiatric disorders, such as depression and anxiety. This meta-analysis sought to compare depression and anxiety levels between IBS patients and healthy controls.

METHODS

We searched major electronic databases (PubMed, EMBASE, MEDLINE, and Cochrane library) to find comparative studies on IBS patients and healthy controls. The primary outcome was a standardized mean difference (SMD) of anxiety and depression levels; sub-group analyses were conducted according to IBS-subtypes.

RESULTS

In total, 2293 IBS patients and 4951 healthy controls from 27 studies were included. In random effect analysis, depression and anxiety levels were significantly higher in IBS patients (pooled SMD = 0.76; 95% CI, 0.62-0.90; P < 0.001; I2 = 77.2% and pooled SMD = 0.84; 95% CI, 0.67-1.01; P < 0.001; I2 = 85.6%, respectively). Both analyses' funnel plots showed symmetry. In meta-regression analysis, heterogeneity was due to the studied region and questionnaire type for both depression and anxiety. In sub-group analyses of IBS-subtype, the pooled SMDs of depression and anxiety levels (IBS with predominant constipation: 0.83 and 0.81, IBS with predominant diarrhea: 0.73 and 0.65, and IBS with mixed bowel habits: 0.62 and 0.75; P < 0.001, respectively) were significantly higher in all IBS-subtypes.

CONCLUSIONS

The present meta-analysis showed depression and anxiety levels to be higher in IBS patients than in healthy controls, regardless of IBS-subtype. However, the gender effect on psychological factors among IBS patients could not be determined and should be evaluated in prospective studies.