A meta-analysis and systematic review of the comorbidity between irritable bowel syndrome and bipolar disorder

Relationships between emotional states, bipolar disorder, and gastrointestinal disorders: A two-sample Mendelian randomization study

BACKGROUND

Functional gastrointestinal symptoms are frequently observed in patients with bipolar affective disorder, but the causal relationship between these conditions remains unclear. To establish causality, this study utilized Mendelian randomization (MR) with data from large-scale genomic research. The investigation aimed to elucidate the relationship between emotional states, bipolar disorder, and functional gastrointestinal disorders (FGIDs).

METHODS

Summary statistics from GWAS were utilized for mood swings (UK biobank, N = 451,619), irritable mood (UK biobank, N = 373,733), bipolar disorder (UK biobank, N = 352,006),functional dyspepsia (FinnGen biobank, N = 194,071), and irritable bowel syndrome (UK biobank, N = 486,601). All GWAS summary statistics were derived from individuals of European ancestry. The primary analysis employed the inverse variance-weighted method for Mendelian randomization (MR). Additionally, we conducted tests for heterogeneity and pleiotropy to ensure the robustness of our results.

RESULTS

A suggestive positive causal relationship was identified between mood swings-related conditions and IBS using the inverse variance-weighted (IVW) method [mood swings-IBS: OR/95%CI: 3.221(2.417,4.294), P(1.42E-15); irritable mood-IBS: OR/95%CI: 1.881(1.615,2.191), P(4.56E-16); bipolar disorder-IBS: OR/95%CI: 1.003(1.001,1.006), P(0.009)]. For functional dyspepsia, a suggestive positive causal relationship was observed with mood swings [mood swings-FD: OR/95%CI: 2.827(1.124,7.109), P(0.027)]. In the reverse analysis, causal relationship was observed between IBS and emotional states [IBS and mood swings: OR/95%CI: 1.030(1.021,1.040), P(1.10E-10); IBS and irritable mood: OR/95%CI: 1.064(1.041,1.087), P(2.58E-08)].

CONCLUSIONS

Mood swings, irritable mood, and bipolar disorder were associated with an increased risk of functional gastrointestinal disorders (FGIDs). Additionally, reverse analysis revealed a causal relationship between irritable bowel syndrome (IBS) and both mood swings and irritable mood. These findings suggest that targeted emotional interventions may be beneficial for patients with FGIDs. Further research is warranted to explore the relationship between mood instability-related disorders and FGIDs, particularly IBS.

Therapeutic modulation of the kynurenine pathway in severe mental illness and comorbidities: A potential role for serotonergic psychedelics

Mounting evidence points towards a crucial role of the kynurenine pathway (KP) in the altered gut-brain axis (GBA) balance in severe mental illness (SMI, namely depression, bipolar disorder, and schizophrenia) and cardiometabolic comorbidities. Preliminary evidence shows that serotonergic psychedelics and their analogues may hold therapeutic potential in addressing the altered KP in the dysregulated GBA in SMI and comorbidities. In fact, aside from their effects on mood, psychedelics elicit therapeutic improvement in preclinical models of obesity, metabolic syndrome, and vascular inflammation, which are highly comorbid with SMI. Here, we review the literature on the therapeutic modulation of the KP in the dysregulated GBA in SMI and comorbidities, and the potential application of psychedelics to address the altered KP in the brain and systemic dysfunction underlying SMI and comorbidities. Psychedelics might therapeutically modulate the KP in the altered GBA in SMI and comorbidities either directly, via altering the metabolic pathway by influencing the rate-limiting enzymes of the KP and affecting the levels of available tryptophan, or indirectly, by affecting the gut microbiome, gut metabolome, metabolism, and the immune system. Despite promising preliminary evidence, the mechanisms and outcomes of the KP modulation with psychedelics in SMI and systemic comorbidities remain largely unknown and require further investigation. Several concerns are discussed surrounding the potential side effects of this approach in specific cohorts of individuals with SMI and systemic comorbidities.

Evidence-Based Clinical Guidelines for Chronic Diarrhea 2023

The Japan Gastroenterological Association (JGA) published the first version of clinical guidelines for chronic diarrhea 2023. These guidelines describe the definition, classification, diagnostic criteria, diagnostic testing methods, epidemiology, pathophysiology, and treatment of chronic diarrhea, and provide flowcharts for the diagnosis and treatment of chronic diarrhea based on the latest evidence. Treatment for chronic diarrhea begins by distinguishing secondary chronic constipation with a clear etiology, such as drug-induced diarrhea, food-induced diarrhea, systemic disease-associated diarrhea, infection-associated diarrhea, organic disease-associated diarrhea, and bile acid diarrhea. The first line of treatment for chronic diarrhea in the narrow sense, defined in these guidelines as functional diarrhea in routine medical care, is lifestyle modification and dietary therapy. The first medicines to be considered for oral treatment are probiotics for regulating the gut microbiome and anti-diarrheals. Other medications, such as 5HT3 receptor antagonists, anticholinergics, Kampo medicine, psychotherapy, antibiotics, bulking agents, adrenergic agonists, and somatostatin analogs, lack sufficient evidence for their use, highlighting a challenge for future research. This Clinical Guidelines for Chronic Diarrhea 2023, which provides the best clinical strategies for treating chronic diarrhea in Japan, will also be useful for medical treatment worldwide.

Risk and protective factors for severe mental disorders in Asia

Among 369 diseases and injuries, the years lived with disability (YLDs) and disability-adjusted life-years (DALYs) rates for severe mental illnesses (SMIs) are within the top 20 %. Research on risk and protective factors for SMIs is critically important, as acting on modifiable factors may reduce their incidence or postpone their onset, while early detection of new cases enables prompt treatment and improves prognosis. However, as most of the studies on these factors are from Western countries, the findings are not generalizable across ethnic groups. This led us to conduct a systematic review of the risk and protective factors for SMIs identified in Asian studies. There were common factors in Asian and Western studies and unique factors in Asian studies. In-depth knowledge of these factors could help reduce disability, and the economic and emotional burden of SMIs. We hope that this review will inform future research and policy-making on mental health in Asian countries.

Gut Microbiota and Gastrointestinal Symptoms in the Global Assessment of Obsessive-Compulsive Disorder: A Narrative Review of Current Evidence and Practical Implications

A growing body of literature suggests a link between bowel syndromes (e.g., irritable bowel syndrome and inflammatory bowel disease), gut microbiome alterations, and psychiatric disorders. This narrative review aims to explore the potential role of the gut microbiome in the pathogenesis and clinical presentation of obsessive-compulsive disorder (OCD) and to explore whether there is sufficient evidence to warrant considering gastrointestinal symptoms and their implication for the gut microbiome during the assessment and treatment of OCD. For this purpose, a PubMed search of studies focusing on OCD, gut microbiota, irritable bowel syndrome, and inflammatory bowel disease was conducted by two independent reviewers. While the current literature on gut microbiome and gastrointestinal issues in OCD remains limited, emerging evidence suggests gut microbiome alterations and high rates of bowel syndromes in this population. These findings emphasize the importance of incorporating comprehensive gastrointestinal assessments into the "global assessment of OCD". Such assessment should encompass various factors, including gastrointestinal physical comorbidities and symptoms, nutritional habits, bowel habits, fluid intake, exercise patterns, and potential microbiome dysfunctions and inflammation. Considering the treatment implications, interventions targeting gut health, such as probiotics and dietary modifications, may hold promise in improving symptoms in OCD patients with comorbid gastrointestinal problems. Further research in this area is warranted to better understand the interplay between gut health and OCD and to explore the effectiveness of targeted interventions in improving clinical outcomes.

Shared genetic architecture between irritable bowel syndrome and psychiatric disorders reveals molecular pathways of the gut-brain axis

BACKGROUND

Irritable bowel syndrome (IBS) often co-occurs with psychiatric and gastrointestinal disorders. A recent genome-wide association study (GWAS) identified several genetic risk variants for IBS. However, most of the heritability remains unidentified, and the genetic overlap with psychiatric and somatic disorders is not quantified beyond genome-wide genetic correlations. Here, we characterize the genetic architecture of IBS, further, investigate its genetic overlap with psychiatric and gastrointestinal phenotypes, and identify novel genomic risk loci.

METHODS

Using GWAS summary statistics of IBS (53,400 cases and 433,201 controls), and psychiatric and gastrointestinal phenotypes, we performed bivariate casual mixture model analysis to characterize the genetic architecture and genetic overlap between these phenotypes. We leveraged identified genetic overlap to boost the discovery of genomic loci associated with IBS, and to identify specific shared loci associated with both IBS and psychiatric and gastrointestinal phenotypes, using the conditional/conjunctional false discovery rate (condFDR/conjFDR) framework. We used functional mapping and gene annotation (FUMA) for functional analyses.

RESULTS

IBS was highly polygenic with 12k trait-influencing variants. We found extensive polygenic overlap between IBS and psychiatric disorders and to a lesser extent with gastrointestinal diseases. We identified 132 independent IBS-associated loci (condFDR < 0.05) by conditioning on psychiatric disorders (n = 127) and gastrointestinal diseases (n = 24). Using conjFDR, 70 unique loci were shared between IBS and psychiatric disorders. Functional analyses of shared loci revealed enrichment for biological pathways of the nervous and immune systems. Genetic correlations and shared loci between psychiatric disorders and IBS subtypes were different.

CONCLUSIONS

We found extensive polygenic overlap of IBS and psychiatric and gastrointestinal phenotypes beyond what was revealed with genetic correlations. Leveraging the overlap, we discovered genetic loci associated with IBS which implicate a wide range of biological pathways beyond the gut-brain axis. Genetic differences may underlie the clinical subtype of IBS. These results increase our understanding of the pathophysiology of IBS which may form the basis for the development of individualized interventions.

Gut Microbial Dysbiosis and Cognitive Impairment in Bipolar Disorder: Current Evidence

Recent studies have reported that the gut microbiota influences mood and cognitive function through the gut-brain axis, which is involved in the pathophysiology of neurocognitive and mental disorders, including Parkinson’s disease, Alzheimer’s disease, and schizophrenia. These disorders have similar pathophysiology to that of cognitive dysfunction in bipolar disorder (BD), including neuroinflammation and dysregulation of various neurotransmitters (i.e., serotonin and dopamine). There is also emerging evidence of alterations in the gut microbial composition of patients with BD, suggesting that gut microbial dysbiosis contributes to disease progression and cognitive impairment in BD. Therefore, microbiota-centered treatment might be an effective adjuvant therapy for BD-related cognitive impairment. Given that studies focusing on connections between the gut microbiota and BD-related cognitive impairment are lagging behind those on other neurocognitive disorders, this review sought to explore the potential mechanisms of how gut microbial dysbiosis affects cognitive function in BD and identify potential microbiota-centered treatment.

Abnormal resting-state local spontaneous functional activity in irritable bowel syndrome patients: A meta-analysis

BACKGROUND

Irritable bowel syndrome (IBS) is a common functional gastrointestinal disorder. The current understanding of the pathogenesis underlying IBS is still unclear. Numerous studies have reported local abnormal resting state spontaneous functional activity in IBS patients in widespread brain regions. However, the results have not yet yielded consistent conclusions. Thus, we investigated common spontaneous functional activity abnormalities in patients with IBS by conducting a voxel-based meta-analysis.

METHODS

Up to December 2021, we performed a systematic search of IBS studies in five databases. These studies investigated the differences of resting state spontaneous brain activity between patients with IBS and healthy controls (HCs). The reference lists of included studies, relevant reviews and meta-analyses were investigated manually. Anisotropic effect-size signed differential mapping (AES-SDM) was applied in this meta-analysis.

RESULTS

Twelve studies encompassing 335 patients with IBS and 327 HCs were included in this meta-analysis. The local brain activities of the left calcarine fissure and surrounding cortex, right postcentral gyrus, left postcentral gyrus, left cerebellum, left inferior temporal gyrus, and left inferior frontal gyrus of triangular part in IBS patients were significantly increased compared with HCs, while the brain activities of the left anterior cingulate and paracingulate gyrus, right middle frontal gyrus, right supramarginal gyrus, left middle frontal gyrus, left precuneus, right putamen and right insula were significantly decreased compared with HCs.

CONCLUSION

The current study expands on a growing literature exploring resting state activity in IBS, which provides useful insights for understanding the underlying pathophysiology of nonorganic functional bowel disease and developing more targeted treatment and intervention strategies.

The Prevalence and Incidence of Irritable Bowel Syndrome and Inflammatory Bowel Disease in Depression and Bipolar Disorder: A Systematic Review and Meta-Analysis

OBJECTIVE

The increased prevalence and incidence of affective disorders among patients with gastrointestinal disease have been well established. However, few studies have investigated the inverse relationship. We aimed to identify all pieces of evidence of the prevalence and incidence of irritable bowel syndrome (IBS) and inflammatory bowel disease (IBD) in people with depression and bipolar disorder.

METHODS

We conducted a systematic review of studies reporting the association between affective disorders (exposure) and IBS or IBD (outcome) in adults. Evidence was evaluated for quality using Joanna Briggs Institute Critical Appraisal tools. Where suitable data were available, meta-analyses were performed.

RESULTS

We identified 18 studies that met the selection criteria, of which 11 provided data on IBS, 5 on IBD, and 2 on both. Overall, people with depression were significantly more likely to have comorbid IBS (risk ratio = 2.42, 95% confidence interval = 1.98-2.96) and to develop new-onset IBS (risk ratio = 1.90, 95% confidence interval = 1.41-2.56) compared with people without depression. They were also more likely to have and develop IBD, and among patients with IBD, significantly increased rates of depression were observed as early as 5 years before diagnosis. Bipolar disorder was not consistently associated with risk of either condition.

CONCLUSIONS

People with depression are at an increased risk of both having and developing lower gastrointestinal disorders. These findings have important implications for how we understand, manage, and prevent this comorbidity in clinical practice. Further studies are needed to improve our understanding of the relationship between bipolar disorder and bowel disease as well as the role of psychotropic medication, particularly selective serotonin reuptake inhibitors.

Altered Metabolomics in Bipolar Depression With Gastrointestinal Symptoms

OBJECTIVE

Although gastrointestinal (GI) symptoms are very common in patients with bipolar disorder (BD), Few studies have researched the pathomechanism behind these symptoms. In the present study, we aim at elucidate the pathomechanism of GI symptoms in BD through metabolomic analysis.

METHOD

BD patients were recruited from Shanxi Bethune Hospital that divided into two groups, each group assessed with the 24-item Hamilton Depression Rating Scale (HAMD-24) according to the presence or absence of GI symptoms. Healthy controls were recruited from the medical examination center of the same hospital. Differential metabolites were identified and further analyzed using Metabo Analyst 3.0 to identify associated metabolic pathways.

RESULTS

There were significantly higher HAMD-24 scores in the GI symptoms group than that of non-GI symptoms group (p = 0.007). Based on metabolomic analysis results, we found that the common disturbances metabolic pathway of both two patients groups was ketone body metabolism, and the unique disturbances metabolic pathways of BD with GI symptoms were fatty acid biosynthesis and tyrosine metabolism, and these changes were independent of dietary habits.

CONCLUSION

BD patients with GI symptoms exhibited disturbances in fatty acid and tyrosine metabolism, perhaps suggesting that the GI symptoms in BD patients are related to disturbances of the gut microbiome. Both groups of patients jointly exhibit disturbances of ketone body metabolism, which may serve as a biomarker for the pathogenesis of BD patients.

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.

The Gut Microbiome in Bipolar Disorder and Pharmacotherapy Management

The gut microbiome is a complex and dynamic community of commensal, symbiotic, and pathogenic microorganisms that exist in a bidirectional relationship with the host. Bacterial functions in the gut play a critical role in healthy host functioning, and its disruption can contribute to many medical conditions. The relationship between gut microbiota and the brain has gained attention in mental health due to the mounting evidence supporting the association of gut bacteria with mood and behavior. Patients with bipolar disorder exhibit an increased frequency of gastrointestinal illnesses such as inflammatory bowel disease, which mechanistically has been linked to microbial community function. While the heterogeneity in microbial communities between individuals might be associated with disease risk, it may also moderate the efficacy or adverse effects associated with the use of medication. The following review highlights published evidence linking the function of gut microbiota both to bipolar disorder risk and to the effect of medications that influence microbiota, inflammation, and mood symptoms.

Preclinical Considerations about Affective Disorders and Pain: A Broadly Intertwined, yet Often Under-Explored, Relationship Having Major Clinical Implications

Background: Pain, a distinctive undesirable experience, encompasses several different and fluctuating presentations across varying mood disorders. Therefore, the present narrative review aimed to shed further light on the matter, accounting for both experimental animal models and clinical observations about major depressive disorder (MDD) pathology. Method: Major databases were inquired from inception until April 2016 for records about MDD and pain. Results: Pain and MDD are tightly associated with each other in a bi-directional fashion. Several cross-sectional and retrospective studies indicated a high presence of pain in the context of mood disorders, including MDD (up to 65%), but also increased prevalence rates in the case of mood disorders documented among people with a primary diagnosis of either psychological or somatic pain (prevalence rates exceeding 45%). The clinical implications of these observations suggest the need to account for mood and pain manifestations as a whole rather than distinct entities in order to deliver more effective interventions. Limitations: Narrative review, lack of systematic control groups (e.g., people with the primary diagnosis at review, but not the associated comorbidity as a study) to allow reliable comparisons. Prevalence rates and clinical features associated with pain varied across different studies as corresponding operational definitions did. Conclusions: Pain may have a detrimental effect on the course of mood disorders-the opposite holds. Promoting a timely recognition and management of such an often neglected comorbidity would therefore represent a primary goal toward the delivery of effective, multi-disciplinary care.

Gut microbial clues to bipolar disorder: State-of-the-art review of current findings and future directions

Trillions of microorganisms inhabiting in the human gut play an essential role in maintaining physical and mental health. The connections between gut microbiome and neuropsychiatric diseases have been recently identified. The pathogenesis of bipolar disorder, a spectrum of diseases manifesting with mood and energy fluctuations, also seems to be involved in the bidirectional modulation of the microbiome-gut-brain (MGB) axis. In this review, we briefly introduce the concept of MGB axis, and then focus on the previous findings in human studies associated with bipolar disorder. These studies provided preliminary evidences on the gut microbial alterations in bipolar disorder. Limitations in these studies and future directions in this research field, such as fecal microbiome transplantation and microbiome-targeted therapy, were discussed. A research framework linking gut microbiome to determinants and health-related outcomes in BD was also proposed. Better characterizing and understanding of gut microbial biosignatures in bipolar patients contribute to clarify the etiology of this intractable disease and pave the new way for treatment innovation.

Gut microbiota and bipolar disorder: a review of mechanisms and potential targets for adjunctive therapy

There is increasing evidence that connections formed between microbiome, the gut, and the brain play a role in health and well-being. Non-pharmaceutical targets for management of mood disorders, such as bipolar disorder, are relatively under-researched. At the same time, it is clear that there is an intimate connection between psychiatry and gastrointestinal health. Here, we have discussed various comorbid conditions associated with bipolar disorders such as inflammation, irritable bowel disease and antibiotic induced mania with importance to demonstrate possible involvement of the gut microbiota. Gut microbiota-targeted preclinical and clinical interventions have demonstrated enhancement in various psychological conditions. Further in this review, we explore links between bipolar disorder, inflammation and gut microbiome with a focus on dietary, pro- and pre-biotic interventions as potential adjuvant therapies for use in the management of mood disorders such as bipolar disorder.

Epidemiology and risk factors for bipolar disorder

Bipolar disorder is a multifactorial illness with uncertain aetiology. Knowledge of potential risk factors enables clinicians to identify patients who are more likely to develop bipolar disorder, which directs further investigation, follow up and caution when prescribing. Ideally, identifying directly causative factors for bipolar disorder would enable intervention on an individual or population level to prevent the development of the illness, and improve outcomes through earlier treatment. This article reviews the epidemiology of bipolar disorder, along with putative demographic, genetic and environmental risk factors, while assessing the strength of these associations and to what extent they might be said to be 'causative'. While numerous genetic and environmental risk factors have been identified, the attributable risk of individual factors is often small, and most are not specific to bipolar disorder but are associated with several mental illnesses. Therefore, while some genetic and environmental factors have strong evidence supporting their association with bipolar disorder, fewer have sufficient evidence to establish causality. There is increasing interest in the role of specific gene-environment interactions, as well as the mechanisms by which risk factors interact to lead to bipolar disorder.

Risk of psychiatric disorders in irritable bowel syndrome-A nationwide, population-based, cohort study

AIMS

This cohort study aimed to investigate the association between irritable bowel syndrome (IBS) and the risk of developing psychiatric disorders.

METHODS

Utilizing the National Health Insurance Research Database (NHIRD) of Taiwan, IBS patients were identified and compared with age, sex, and index year-matched controls (1:3).

RESULTS

Of the IBS subjects, 3934 in 22 356 (17.60%, or 1533.68 per 100 000 person-years) developed psychiatric disorders when compared with 6127 in 67 068 (9.14%, or 802 per 100 000 person-years) in the non-IBS control group. Fine and Gray's survival analysis revealed that the study subjects were more likely to develop psychiatric disorders. The crude hazard ratio (HR) is 3.767 (95% CI: 3.614-3.925, P < .001), and the adjusted HR is 3.598 (95% CI: 3.452-3.752, P < .001) in the risk of developing psychiatric disorders after being adjusted for age, sex, comorbidities, geographical area of residence, urbanisation level of residence, and monthly insurance premiums. The cohort study revealed that IBS subjects were associated with an increased risk of anxiety, depression, bipolar, and sleep disorders.

CONCLUSIONS

This cohort study, using NHIRD, shows evidence support that patients with IBS have a 3.6-fold risk of developing psychiatric disorders. Other large or national datasets should be done to explore to underlying mechanisms.

Medical Comorbidities in Bipolar Disorder

PURPOSE OF REVIEW

Bipolar disorder (BD) medical comorbidity presents significant clinical and public health concerns with serious impact on health. The aim of this article is to present an updated narrative review of original research articles (case control, longitudinal cohort, and cross-sectional studies) and meta-analyses published in English language journals from January 2013 to May 2017 focusing on general medical comorbidity in BD, including the added risks of iatrogenic factors relevant to the treatment of BD.

RECENT FINDINGS

We found numerous patterns of association between BD and various medical disorders involving multiple organ systems. One pattern indicated reciprocal increase in the rate of each comorbid condition, such as an increased rate of BD in asthma or migraine, and likewise an increase in the rate of asthma or migraine in patients with BD. A second pattern was a predominantly unidirectional increase in the rate of BD in patients with certain medical disorders, such as multiple sclerosis or cerebellar diseases. A third pattern was a predominantly unidirectional increased rate of medical disorders in patients with BD. One study suggested the potential involvement of genetic mechanisms for the association between BD and migraine. Most of the studies had cross-sectional or retrospective designs, and many relied on analysis of large administrative databases inviting multiple potential biases. Our review highlights the association between BD and a variety of medical disorders. Further research is needed to elucidate the potential underlying etiopathological mechanisms that contribute to observed comorbidities. The results of this review also emphasize the need for comprehensive screening for medical disorders in BD and for adoption of an integrated model of care to address these complex comorbidities.

Randomized controlled study of efficacy and safety of drotaverine hydrochloride in patients with irritable bowel syndrome

BACKGROUND

This study aimed to assess the efficacy and safety of drotaverine hydrochloride (DHC) in Chinese patients with irritable bowel syndrome (IBS).

METHODS

Totally, 144 patients with IBS were included and randomly divided into treatment group and placebo group in a 1:1 ratio. Patients received either DHC or placebo 80-mg tablet, 3 times daily for a total of 4 weeks. The primary outcome included abdominal pain, measured by the visual analog scale (VAS), and weekly stool frequency. The secondary outcomes were measured by the Bristol scale, and the 36-item short form health survey (SF-36), as well as the adverse events recorded during the treatment period. All those outcomes were measured at the end of 4-week treatment.

RESULTS

The total and different types of IBS in VAS, stool frequency, and Bristol score were significantly better in the treatment group than those in the placebo group at the end of 4-week treatment. However, no significant difference was found in quality of life, measured by SF-36 scale between 2 groups. Additionally, no serious and significant differences in adverse events were found in and between both groups.

CONCLUSION

The findings suggest that DHC has promising efficacy to enhance symptoms of IBS in Chinese population.

Systematic assessment of environmental risk factors for bipolar disorder: an umbrella review of systematic reviews and meta-analyses

OBJECTIVES

The pathophysiology of bipolar disorder is likely to involve both genetic and environmental risk factors. In our study, we aimed to perform a systematic search of environmental risk factors for BD. In addition, we assessed possible hints of bias in this literature, and identified risk factors supported by high epidemiological credibility.

METHODS

We searched the Pubmed/MEDLINE, EMBASE and PsycInfo databases up to 7 October 2016 to identify systematic reviews and meta-analyses of observational studies that assessed associations between putative environmental risk factors and BD. For each meta-analysis, we estimated its summary effect size by means of both random- and fixed-effects models, 95% confidence intervals (CIs), the 95% prediction interval, and heterogeneity. Evidence of small-study effects and excess of significance bias was also assessed.

RESULTS

Sixteen publications met the inclusion criteria (seven meta-analyses and nine qualitative systematic reviews). Fifty-one unique environmental risk factors for BD were evaluated. Six meta-analyses investigated associations with a risk factor for BD. Only irritable bowel syndrome (IBS) emerged as a risk factor for BD supported by convincing evidence (k=6; odds ratio [OR]=2.48; 95% CI=2.35-2.61; P<.001), and childhood adversity was supported by highly suggestive evidence. Asthma and obesity were risk factors for BD supported by suggestive evidence, and seropositivity to Toxoplasma gondii and a history of head injury were supported by weak evidence.

CONCLUSIONS

Notwithstanding that several environmental risk factors for BD were identified, few meta-analyses of observational studies were available. Therefore, further well-designed and adequately powered studies are necessary to map the environmental risk factors for BD.