Brain-gut interaction in irritable bowel syndrome

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

BACKGROUND

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

METHODS/DESIGN

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

DISCUSSION

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

REGISTRATION FOR TRIAL

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

Effects of antidepressants in patients with irritable bowel syndrome and comorbid depression

BACKGROUND

Irritable bowel syndrome (IBS) is a functional gastrointestinal disorder that affects up to 15% of community dwelling individuals. Psychiatric comorbidities, particularly symptoms of major depressive disorder (MDD), occur in up to 90% of patients with IBS.

OBJECTIVE

This article reviews the available literature on the use of antidepressants for both IBS and psychiatric depressive symptoms in patients with IBS.

METHODS

MEDLINE and International Pharmaceutical Abstracts (both, 1980-May 2010) were searched for English-language publications that involved antidepressant treatment of MDD in patients with IBS. The search terms were depression, irritable, bowel, treatment, and functional. The reference lists of key articles were searched for additional pertinent articles. Randomized controlled trials published in the past 10 years were given priority.

RESULTS

Of 46 articles identified by the literature search, 11 were included in the review: 4 studies of selective serotonin reuptake inhibitors (SSRIs), 4 of tricyclic antidepressants (TCAs), 1 comparing an SSRI and a TCA, 1 of the serotonin-norepinephrine reuptake inhibitor duloxetine, and a case report involving the tetracyclic antidepressant mirtazapine. Most of the identified studies excluded patients with a diagnosis of depression and/or anxiety. No controlled studies were identified in which the primary outcome was objective assessment of MDD symptoms in patients with IBS. Two of the SSRI studies, one of citalopram and the other of paroxetine, reported approximately 50% improvement in IBS symptoms (both studies, P = 0.01); the study of paroxetine reported a 30% improvement in scores on the Beck Depression Inventory (P = 0.01). The 2 studies of fluoxetine found no statistically significant benefit on IBS symptoms. TCAs were reported to have benefits on IBS symptoms, predominantly diarrhea. Only one of the TCA studies examined and found a significant improvement in depressive symptoms with desipramine 150 mg/d (P = 0.025). Both the open-label study of duloxetine and the case report involving mirtazapine found improvements in IBS and psychiatric symptoms.

CONCLUSIONS

The evidence for the benefit of antidepressant treatment in patients with IBS and comorbid depression was limited and contradictory. Some anti-depressants may help symptoms of IBS, although whether the same drugs and doses are associated with improvements in concomitant depressive symptoms remains to be elucidated.

Tegaserod in the treatment of irritable bowel syndrome with constipation

Tegaserod, a novel serotonin receptor agonist, has gained acceptance and widespread use for the treatment of women with irritable bowel syndrome and constipation. Development of this therapy evolved from the emerging role of serotonin in gastrointestinal motor, secretory and sensory functions. The efficacy and safety of tegaserod has been well established in women suffering from irritable bowel syndrome with constipation. Large, randomized, double-blind, placebo-controlled trials involving more than 3500 predominantly female patients with irritable bowel syndrome and constipation have demonstrated the superiority of tegaserod over placebo in improving global and individual symptoms. The most common side effects of tegaserod in clinical trials were diarrhea and headache. Recent data suggest that retreatment with tegaserod after a drug holiday is efficacious, opening the door to the possibility of intermittent therapy for patients with irritable bowel syndrome and constipation. Areas in need of further investigation include the role of tegaserod in the treatment of pain and bloating in irritable bowel syndrome, whether tegaserod has a role in male patients, the long-term efficacy of tegaserod, whether tolerance develops in a subset of patients with extended therapy and whether tegaserod is beneficial for the treatment of other functional gastrointestinal disorders.

Review article: The role of serotonergic agents in the treatment of patients with primary chronic constipation

Chronic constipation is a highly prevalent disorder that is associated with significant direct and indirect costs and has substantial impact on patient quality of life. It is more common among women and non-white populations and is evenly distributed across adult age groups. Constipation is a heterogeneous disorder associated with multiple symptoms and aetiologies. Recent research has increased our understanding of the pathogenesis of this disorder and the central role of the neurotransmitter serotonin in mediating gastrointestinal motility, secretion and sensation. Abnormal serotonin signalling and reuptake appear to play central roles in the symptoms of a subset of patients with chronic constipation. This observation provides a rationale for the use of targeted serotonergic agents for the treatment of chronic constipation. As the role of serotonin in gastrointestinal function is further elucidated and additional candidate drugs are developed, it is likely that serotonergic agents will afford additional treatment options for patients with chronic constipation. This article provides a concise review of the evidence supporting a role for serotonin in the pathogenesis of chronic constipation and a summary of the currently available evidence supporting the use of serotonergic agents for this disorder.

Eating disorders and irritable bowel syndrome: is there a link?

OBJECTIVE

The relationship between eating disorders (ED) and irritable bowel syndrome (IBS) is poorly understood. We wanted to determine the prevalence of IBS in a large sample of eating disordered individuals, examine the timing of onset of these disorders and assess whether there are any predictors of IBS symptoms in ED sufferers.

METHODS

Participants with a current or past ED were recruited from a volunteer register. Two hundred thirty-four respondents completed a questionnaire on IBS devised for the study. ED symptoms were assessed using the Eating Disorders Examination-Questionnaire (EDE-Q).

RESULTS

Sixty-four percent currently met the widely used Manning criteria for IBS. The majority of participants (87%) had developed their ED before the onset of IBS, with a mean of 10 years between the onset of ED and IBS. All EDE subscales were associated with current IBS symptoms, whereas ED duration was not.

CONCLUSION

Preliminary findings suggest that EDs may increase the risk of developing IBS.

Rationale for using serotonergic agents to treat irritable bowel syndrome

PURPOSE

The role of serotonin in gastrointestinal (GI)-tract functioning, the pharmacologic rationale for using serotonergic agents in the treatment of irritable bowel syndrome (IBS), and clinical experience with novel serotonergic agents are described.

SUMMARY

IBS is a common multisymptom disorder that is associated with a high socioeconomic burden. The goal of treatment is to provide rapid and sustained global relief of the multiple symptoms of IBS with a single, effective, well-tolerated agent. Traditional treatment options target single symptoms, and many patients are dissatisfied with the level of relief achieved and adverse effects. Research has revealed that serotonin is involved in three major actions in the gut: (1) mediating intestinal motility, (2) mediating intestinal secretion in the GI tract, and (3) modulating perception in the bowels. Serotonin is also a vital link in the brain-gut axis. Alterations in key elements of serotonin signaling have been demonstrated in patients with IBS. Tegaserod, a selective serotonin type 4 (5-HT(4))-receptor partial agonist, is indicated for use in women with IBS whose primary bowel symptom is constipation. Alosetron, a 5-HT(3)-receptor antagonist, is indicated for use in women with severe diarrhea-predominant IBS in whom traditional therapies have failed. The clinical usefulness of several other serotonergic agents for IBS is being investigated.

CONCLUSION

The use of serotonergic agents in patients with IBS is based on the critical role that serotonin plays in the maintenance of normal gut function and brain-gut communication. Pharmacologic therapies targeting specific serotonin receptors represent an important step in the management of IBS.

Central nervous system involvement in functional gastrointestinal disorders

Although functional gastrointestinal disorders (FGID) are common, their pathophysiology remains incompletely understood. It is generally accepted that dysfunction of the bidirectional pathways between the gastrointestinal tract and the central nervous system (the 'brain-gut axis') at any level can cause FGID symptoms. In this review article, we focus on the role of the central nervous system in the brain-gut axis. First, we describe the functional anatomy of the brain-gut axis. Second, we focus on the results from brain-imaging studies both in healthy volunteers and in FGID patients. These new investigational techniques made identification of brain regions critically involved in processing of visceral afferent information possible. Differences in central nervous system response to visceral stimuli between controls and FGID patients will be highlighted. Third, we will address the issue of high comorbidity with psychiatric disorders. Some hypotheses about common pathophysiological substrates will be discussed.