Association between gastrointestinal symptoms and affectivity in patients with bipolar disorder

A comprehensive Mendelian randomization study highlights the relationship between psychiatric disorders and non-tumor gastrointestinal diseases

Objective

Previous observational studies revealed the potential correlation between psychiatric disorders (PDs) and non-tumor gastrointestinal diseases (NTGDs). However, their causation remains unclear.

Methods

We explored the causal relationship between PDs and NTGDs through bidirectional two-sample Mendelian randomization (MR) study. Large-scale genome-wide association study (GWAS) summary statistics and bidirectional two-sample MR study were used to assess the causality between PDs and NTGDs. Multiple sensitivity analyses were used to identify the robustness of our results.

Results

We found that major depression was causally associated with increased risk of gastric ulcer (OR: 1.812, 95% CI: 1.320-2.487, p < 0.001) and irritable bowel syndrome (OR: 1.645, 95% CI: 1.291-2.097, p < 0.001). Meanwhile, genetically predicted gastroesophageal reflux disease contributed to the increased risk of anxiety disorders (OR: 1.425, 95% CI: 1.295-1.568, p < 0.001), and ulcerative colitis was related to increased risk of attention deficit/hyperactivity disorder (OR: 1.042, 95% CI: 1.008-1.078, p = 0.0157).

Conclusion

Our study provided MR evidence to support the close causality and identify the specific direction between eight PDs and eight common NTGDs. Experimental studies to further examine the causality, underlying mechanism, and therapeutic potential of PDs and NTGDs are required.

The causal role of multiple psycho-emotional disorders in gastroesophageal reflux disease: A two-sample Mendelian randomized study

BACKGROUND

Observational studies have previously shown a potential link between psycho-emotional disorders, such as mood swings, highly strung, anxious feelings, and gastroesophageal reflux disease (GERD). However, the credibility of these associations could be influenced by various confounding factors. Consequently, our study sought to employ a Mendelian randomization (MR) approach to elucidate a potential causal relationship between psycho-emotional disorders and GERD.

METHOD

Information on independent genetic variants linked to mood swings, highly strung, and anxious feelings was gathered from European populations participating in the IEU Open GWAS research. The FinnGen Consortium provided the genome-wide association study (GWAS) summary statistics for GERD. Our analysis employed the inverse variance weighted (IVW) method under the random effects model as the main analytical method. To further bolster our findings, we employed the weighted median and MR Egger methods. In addition, we conducted a series of sensitivity analyses.

RESULTS

Our study supports the existence of a causal relationship between psycho-emotional disorders and GERD. Mood swings, highly strung, and anxious feelings adversely affected GERD risk (mood swings: OR 2.21, 95% CI 1.19-5.59, p = 3.09 × 10-2; highly strung: OR 5.63, 95% CI 1.77-17.94, p = 3.42 × 10-3; anxious feelings: OR 2.48, 95% CI 1.08-4.33, p = 2.89 × 10-2).

CONCLUSION

This Mendelian randomization study provides robust support for the notion that mood swings, highly strung and anxious feelings, are associated with an increased risk of developing GERD.

Restraint stress-associated gastrointestinal injury and implications from the Evans blue-fed restraint stress mouse model

The association between stress and gastrointestinal (GI) tract diseases is well established, while the exact mechanism remains elusive. As a result, it is urgent to establish mouse models to investigate restraint stress-associated GI leakage, but current models have their limitations. A new Evans blue-fed restraint mouse model has recently been developed that allows researchers to study restraint stress-associated GI leakage in live animals. This review article will focus on this model, including its mechanisms, clinical implications, and applications for studying restraint stress-associated GI injury. Recent findings from studies using this model will also be highlighted, along with their potential for diagnosis and treatment. The article aims to discuss about current research and provide recommendations for further study, ultimately improving our understanding of the link between stress and GI injury and improving patient outcomes.

Privacy-Preserving Federated Model Predicting Bipolar Transition in Patients With Depression: Prediction Model Development Study

BACKGROUND

Mood disorder has emerged as a serious concern for public health; in particular, bipolar disorder has a less favorable prognosis than depression. Although prompt recognition of depression conversion to bipolar disorder is needed, early prediction is challenging due to overlapping symptoms. Recently, there have been attempts to develop a prediction model by using federated learning. Federated learning in medical fields is a method for training multi-institutional machine learning models without patient-level data sharing.

OBJECTIVE

This study aims to develop and validate a federated, differentially private multi-institutional bipolar transition prediction model.

METHODS

This retrospective study enrolled patients diagnosed with the first depressive episode at 5 tertiary hospitals in South Korea. We developed models for predicting bipolar transition by using data from 17,631 patients in 4 institutions. Further, we used data from 4541 patients for external validation from 1 institution. We created standardized pipelines to extract large-scale clinical features from the 4 institutions without any code modification. Moreover, we performed feature selection in a federated environment for computational efficiency and applied differential privacy to gradient updates. Finally, we compared the federated and the 4 local models developed with each hospital's data on internal and external validation data sets.

RESULTS

In the internal data set, 279 out of 17,631 patients showed bipolar disorder transition. In the external data set, 39 out of 4541 patients showed bipolar disorder transition. The average performance of the federated model in the internal test (area under the curve [AUC] 0.726) and external validation (AUC 0.719) data sets was higher than that of the other locally developed models (AUC 0.642-0.707 and AUC 0.642-0.699, respectively). In the federated model, classifications were driven by several predictors such as the Charlson index (low scores were associated with bipolar transition, which may be due to younger age), severe depression, anxiolytics, young age, and visiting months (the bipolar transition was associated with seasonality, especially during the spring and summer months).

CONCLUSIONS

We developed and validated a differentially private federated model by using distributed multi-institutional psychiatric data with standardized pipelines in a real-world environment. The federated model performed better than models using local data only.

The Role of Activating Transcription Factor 3 in Metformin's Alleviation of Gastrointestinal Injury Induced by Restraint Stress in Mice

Metformin is one of the most commonly used drugs for type 2 diabetes mellitus. In addition to its anti-diabetic property, evidence suggests more potential applications for metformin, such as antiaging, cellular protection, and anti-inflammation. Studies have reported that metformin activates pathways with anti-inflammatory effects, enhances the integrity of gut epithelial tight junctions, and promotes a healthy gut microbiome. These actions contribute to the protective effect of metformin against gastrointestinal (GI) tract injury. However, whether metformin plays a protective role in psychological-stress-associated GI tract injury remains elusive. We aim to elucidate the potential protective effect of metformin on the GI system and develop an effective intervention strategy to counteract GI injury induced by acute psychological stress. By monitoring the levels of GI-nonabsorbable Evans blue dye in the bloodstream, we assessed the progression of GI injury in live mice. Our findings demonstrate that the administration of metformin effectively mitigated GI leakage caused by psychological stress. The GI protective effect of metformin is more potent when used on wild-type mice than on activating-transcription-factor 3 (ATF3)-deficient (ATF3^-/-) mice. As such, metformin-mediated rescue was conducted in an ATF3-dependent manner. In addition, metformin-mediated protection is associated with the induction of stress-induced GI mRNA expressions of the stress-induced genes ATF3 and AMP-activated protein kinase. Furthermore, metformin treatment-mediated protection of CD326⁺ GI epithelial cells against stress-induced apoptotic cell death was observed in wild-type but not in ATF3^-/- mice. These results suggest that metformin plays a protective role in stress-induced GI injury and that ATF3 is an essential regulator for metformin-mediated rescue of stress-induced GI tract injury.

The Role of the Gut Microbiome in Bipolar Disorder and its Common Comorbidities

Bipolar disorder is a decidedly heterogeneous and multifactorial disease, with significant psychosocial and medical disease burden. Much difficulty has been encountered in developing novel therapeutics and objective biomarkers for clinical use in this population. In that regard, gut-microbial homeostasis appears to modulate several key pathways relevant to a variety of psychiatric, metabolic, and inflammatory disorders. Microbial impact on immune, endocrine, endocannabinoid, kynurenine, and other pathways are discussed throughout this review. Emphasis is placed on this system's relevance to current pharmacology, diet, and comorbid illness in bipolar disorder. Despite the high level of optimism promoted in many reviews on this topic, substantial obstacles exist before any microbiome-related findings can provide meaningful clinical utility. Beyond a comprehensive overview of pathophysiology, this review hopes to highlight several key areas where progress is needed. As well, novel microbiome-associated suggestions are presented for future research.

Impact of Gastrointestinal Symptoms on Health-Related Quality of Life in an Australian Parkinson’s Disease Cohort

Background. Gastrointestinal symptoms (GIS) in people with Parkinson’s disease (PwP) are often underreported and may remain untreated. Constipation is a common nonmotor symptom that can adversely affect health-related quality of life (QoL); however, the impact of other GIS has not been adequately investigated. Objectives. To investigate the relationship between QoL and constipation using the Bristol Stool Chart, bowel movement frequency, and a perceived constipation measure; and to explore the relationship between QoL and other GIS in an Australian PD cohort. Methods. The impact of constipation and other GIS on QoL, as measured using the PDQ-39 scale, was assessed in a cohort of 144 (89 males, 55 females) clinic-attending PwP. Constipation was assessed using the Bristol Stool Chart as well as a composite constipation measure, and the Gastrointestinal Symptom Rating Scale (GSRS) was used to rate other GIS. Covariate corrected linear regression models were utilised to determine significant associations between GIS and QoL scores. Results. Individual and combined constipation measures were significantly associated with poorer QoL ( $p=0.032$ and $p=0.002$ , respectively). Analysis of GSRS symptom domains showed that in addition to symptoms of gastrointestinal hypomotility, a number of other symptoms such as increased eructation and increased flatus were also associated with poorer QoL. Conclusions. The findings point to the importance of GIS as contributor to health-related QoL in PwP. A better understanding of the relationship between GIS and QoL will help facilitate the development of more effective screening and treatment programs to improve symptom management and QoL for PwP.

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.

Gut Microbiota – A Potential Contributor in the Pathogenesis of Bipolar Disorder

Bipolar disorder (BD) is one of the major psychiatric disorders that is characterized by recurrent episodes of depression and mania (or hypomania), leading to seriously adverse outcomes with unclear pathogenesis. There is an underlying relationship between bacterial communities residing in the gut and brain function, which together form the gut-brain axis (GBA). Recent studies have shown that changes in the gut microbiota have been observed in a large number of BD patients, so the axis may play a role in the pathogenesis of BD. This review summarizes briefly the relationship between the GBA and brain function, the composition and changes of gut microbiota in patients with BD, and further explores the potential role of GBA-related pathway in the pathogenesis of BD as well as the limitations in this field at present in order to provide new ideas for the future etiology research and drug development.

Self-Reported Pain and Emotional Reactivity in Bipolar Disorder: A Prospective FACE-BD Study

In patients with bipolar disorder (BD), pain prevalence is close to 30%. It is important to determine whether pain influences BD course and to identify factors associated with pain in BD in order to guide BD management. This naturalistic, prospective study used data on 880 patients with BD from the French FACE-BD cohort who were divided into two groups according to the presence or absence of pain. Multivariate models were used to test whether pain was associated with affective states and personality traits while controlling for confounders. Then, multivariate models were used to test whether pain at baseline predicted global life functioning and depressive symptomatology at one year. At baseline, 22% of patients self-reported pain. The pain was associated with depressive symptomatology, levels of emotional reactivity in a quadratic relationship, and a composite variable of personality traits (affective lability, affective intensity, hostility/anger, and impulsivity). At one year, the pain was predictive of depression and lower global life functioning. Pain worsens mental health and well-being in patients with BD. The role of emotions, depression, and personality traits in pain has to be elucidated to better understand the high prevalence of pain in BD and to promote specific therapeutic strategies for patients experiencing pain.

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.

Activating Transcription Factor 3 Protects against Restraint Stress-Induced Gastrointestinal Injury in Mice

Psychological stress increases the risk of gastrointestinal (GI) tract diseases, which involve bidirectional communication of the GI and nerves systems. Acute stress leads to GI ulcers; however, the mechanism of the native cellular protection pathway, which safeguards tissue integrality and maintains GI homeostasis, remains to be investigated. In a mouse model of this study, restraint stress induced GI leakage, abnormal tight junction protein expression, and cell death of gut epithelial cells. The expression of activating transcription factor 3 (ATF3), a stress-responsive transcription factor, is upregulated in the GI tissues of stressed animals. ATF3-deficient mice displayed an exacerbated phenotype of GI injuries. These results suggested that, in response to stress, ATF3 is part of the native cellular protective pathway in the GI system, which could be a molecular target for managing psychological stress-induced GI tract diseases.

Psychophysiological Effects of Lactobacillus plantarum PS128 in Patients with Major Depressive Disorder: A Preliminary 8-Week Open Trial

Recent studies have suggested that gut–brain axis may be one of the mechanisms of major depression disorder (MDD). The current study aimed to investigate the effects of Lactobacillus plantarum PS128 (PS128) on psychophysiology in patients with MDD. We recruited 11 patients with MDD and gave them PS128 for 8 weeks. We compared depression symptoms, serum markers of inflammation and gut permeability, and gut microbiota before and after 8-week intervention and also explored the correlations among symptoms, biomarkers, and gut microbiota. After 8-week PS128 intervention, scores of Hamilton Depression Rating Scale-17 and Depression and Somatic symptoms Scale significantly decreased. Serum levels of high sensitivity c-reactive protein, interluekin-6, and tumor necrosis factor-α, zonulin and intestinal fatty acid binding protein, and the composition of gut microbiota did not significantly change after 8-week PS128 intervention. However, we found changes of some genera were correlated with changes of symptoms and biomarkers. In conclusion, this is an open trial with small sample size and has several limitations. The results need to be verified by randomized, double-blind, placebo-controlled trial with larger sample size.

Fecal Short-Chain Fatty Acid Ratios as Related to Gastrointestinal and Depressive Symptoms in Young Adults

OBJECTIVE

Short-chain fatty acids (SCFAs) are produced by the gut microbiota and may reflect health. Gut symptoms are common in individuals with depressive disorders, and recent data indicate relationships between gut microbiota and psychiatric health. We aimed to investigate potential associations between SCFAs and self-reported depressive and gut symptoms in young adults.

METHODS

Fecal samples from 164 individuals (125 were patients with psychiatric disorders: mean [standard deviation] age = 21.9 [2.6] years, 14% men; 39 nonpsychiatric controls: age = 28.5 [9.5] years, 38% men) were analyzed for the SCFA acetate, butyrate, and propionate by nuclear magnetic resonance spectroscopy. We then compared SCFA ratios with dimensional measures of self-reported depressive and gut symptoms.

RESULTS

Depressive symptoms showed a positive association with acetate levels (ρ = 0.235, p = .003) and negative associations with both butyrate (ρ = -0.195, p = .014) and propionate levels (ρ = -0.201, p = .009) in relation to total SCFA levels. Furthermore, symptoms of diarrhea showed positive associations with acetate (ρ = 0.217, p = .010) and negative associations with propionate in relation to total SCFA levels (ρ = 0.229, p = 0-007). Cluster analysis revealed a heterogeneous pattern where shifts in SCFA ratios were observed in individuals with elevated levels of depressive symptoms, elevated levels of gut symptoms, or both.

CONCLUSIONS

Shifts in SCFAs are associated with both depressive symptoms and gut symptoms in young adults and may have of relevance for treatment.

Psychological comorbidity in gastrointestinal diseases: Update on the brain-gut-microbiome axis

The high comorbidity of psychological disorders in both functional and organic gastrointestinal diseases suggests the intimate and complex link between the brain and the gut. Termed the brain-gut axis, this bidirectional communication between the central nervous system and enteric nervous system relies on immune, endocrine, neural, and metabolic pathways. There is increasing evidence that the gut microbiome is a key part of this system, and dysregulation of the brain-gut-microbiome axis (BGMA) has been implicated in disorders of brain-gut interaction, including irritable bowel syndrome, and in neuropsychiatric disorders, including depression, Alzheimer's disease, and autism spectrum disorder. Further, alterations in the gut microbiome have been implicated in the pathogenesis of organic gastrointestinal diseases, including inflammatory bowel disease. The BGMA is an attractive therapeutic target, as using prebiotics, probiotics, or postbiotics to modify the gut microbiome or mimic gut microbial signals could provide novel treatment options to address these debilitating diseases. However, despite significant advancements in our understanding of the BGMA, clinical data is lacking. In this article, we will review current understanding of the comorbidity of gastrointestinal diseases and psychological disorders. We will also review the current evidence supporting the key role of the BGMA in this pathology. Finally, we will discuss the clinical implications of the BGMA in the evaluation and management of psychological and gastrointestinal disorders.

Characterization of Gastrointestinal Symptom Type and Severity in Parkinson's Disease: A Case-Control Study in an Australian Cohort

Background

While constipation is a well-known non-motor symptom which may precede the onset of the classical motor symptoms of PD, there have been few comprehensive studies of gastrointestinal (GI) symptoms in people with PD (PwP).

Objectives

To investigate the spectrum of GI symptoms in an Australian PwP cohort and their relationship to use of anti-parkinsonian medications dietary habits and smoking.

Methods

The prevalence and severity of GI symptoms were compared in a group of 163 PwP and 113 healthy control subjects using the Gastrointestinal Symptom Rating Scale (GSRS). Corrected linear regression models were used to determine differences between PwP and controls, and to investigate the influence of different classes of anti-Parkinsonian medications.

Results

PwP reported a greater frequency of constipation and GI-associated illnesses when compared to healthy controls. Total GSRS scores (P < 0.0001), upper GI symptoms (P < 0.0001), and hypoactive GI Symptoms (P < 0.0001) were all significantly greater in the PD cohort than controls. Further analyses revealed a positive association between the use of anti-Parkinsonian medications and total GSRS scores (P < 0.001), as well as upper GI symptoms (P < 0.001) and hypoactive GI function (P < 0.001).

Conclusions

This study illustrates the frequency and array of GI symptoms in a large PD cohort. The findings indicate that anti-parkinsonian medications play an important role in the presentation and development of GI symptoms.

Sex Differences in the Gut-Brain Axis: Implications for Mental Health

PURPOSE OF REVIEW

The purpose of this article is to highlight how sex differences in the gut-brain axis may contribute to the discrepancies in incidence of neurodevelopmental, psychiatric, and neurodegenerative disorders between females and males. We focus on autism spectrum disorder, psychotic disorders, stress and anxiety disorders, depression, Alzheimer's disease, and Parkinson's disease and additionally discuss the comorbidity between inflammatory bowel disorder and mental health disorders.

RECENT FINDINGS

Human and animal studies show that sex may modify the relationship between the gut or immune system and brain and behavior. Sex also appears to modify the effect of microbial treatments such as probiotics and antibiotics on brain and behavior. There is emerging evidence that assessing the role of sex in the gut-brain axis may help elucidate the etiology of and identify effective treatments for neurodevelopmental, psychiatric, and neurodegenerative disorders.

Irritable bowel syndrome-like symptoms in treated microscopic colitis patients compared with controls: a cross-sectional study

Background

The prevalence of irritable bowel syndrome (IBS)-like symptoms is high in untreated patients with microscopic colitis (MC), but there is uncertainty of the prevalence of IBS-like symptoms in treated patients. We assessed the degree of IBS-like symptoms in patients with MC in comparison to control subjects, and investigated the association between IBS-like symptoms and faecal calprotectin (FC) in MC patients.

Methods

Patients with an established MC diagnosis (n = 57) were compared to sex- and age-matched controls (n = 138) for scores in the GSRS-IBS (Gastrointestinal Symptom Rating Scale for Irritable Bowel Syndrome) and HADS (Hospital Anxiety Depression Scale). In MC patients, an FC level was simultaneously analysed.

Results

The median interval from MC diagnoses to the time the subjects participated in the study was 5.5 years (25th–75th percentiles; 4.5–9.5 years). The total GSRS-IBS score, subscores for abdominal pain, bloating, and diarrhoea were significantly higher in MC patients compared to controls (all P < 0.001). There was a significant correlation between FC levels and reported bowel frequency (P = 0.023), but there was no correlation between FC levels and GSRS-IBS scores. Patients with MC had significantly higher scores on anxiety (HADS-A) (P < 0.001) and used more selective serotonin-reuptake-inhibitor drugs (P = 0.016) than the control subjects. However, only the control subjects (not the patients with MC) showed significant correlations between GSRS-IBS scores and HADS scores.

Conclusions

Patients with MC reported more IBS-like symptoms and anxiety than control subjects but neither FC levels nor symptoms of affectivity were significantly correlated with IBS-like symptoms.

Association between gastroesophageal reflux disease and depression disorder: A protocol for systematic review and meta-analysis

BACKGROUND

This study will systematically synthesize the evidence on the potential association between gastroesophageal reflux disease (GERD) and depression disorder (DD).

METHODS

We will search the following electronic bibliographic databases: PubMed/MEDLINE, Embase, Cochrane Library, Web of Science, the Chinese Bio Medical Literature Database, China National Knowledge Infrastructure (CNKI), the China Science and Technology Journal database (VIP) and Wanfang Data. In addition, ongoing trials will be retrieved from the WHO ICTRP Search Portal, the Chinese Clinical Trial Register and The Clinical Trials Register. Articles related to gastroesophageal reflux disease and depression will be searched. And language and time will be unlimited.

RESULTS

The study will afford additional insight into the investigation the association between GERD and DD.

CONCLUSIONS

The results of this study will provide helpful evidence to explore the association between GERD and DD.

REGISTRATION NUMBER

INPLASY202090026.

Borderline patients have difficulties describing feelings; bipolar II patients describe difficult feelings. An alexithymia study

OBJECTIVE

Apparent similarities between borderline personality disorder (BPD) and bipolar II disorder (BIP-II) contribute to clinical difficulties in distinguishing between the disorders. Here, we aimed to explore how subjective Difficulties with the Identification and Description of Feelings (DIDF), a major constituent of the alexithymia construct and assessed as a part of the Toronto Alexithymia Scale (TAS), are related to relationship problems and health complaints in these groups.

METHODS

Twenty-two patients with BPD; 22 patients with BIP-II; and 23 healthy controls (HC) completed TAS. Health complaints, including symptoms associated with mood swings, were assessed with the Giessener Subjective Complaints List (Giessener Beschwerdebogen-GBB), and relationship problems with the Health of the Nation Outcome scale, Relationship item (HoNOSR). Bivariate correlations were run.

RESULTS

Both patient groups had high DIDF and GBB scores. In BPD only, there was a significant positive correlation between DIDF and HoNOSR. In BIP-II only, there was a significant positive correlation between DIDF and GBB total score. In BIP-II, DIDF correlated highly with those GBB subscales assessing symptoms typically occurring during bipolar mood swings (cardiovascular and gastrointestinal symptoms, exhaustion).

CONCLUSION

Our results suggest that in BPD, high DIDF scores represent genuine problems with identifying and describing emotions which are expected to correlate with relationship problems. In BIP-II, high DIDF scores could potentially represent difficulties with understanding the unpredictable symptoms of bipolar mood swings. The findings suggest that difficulties with identifying and describing feelings in patients should be carefully explored to increase the validity of the diagnostic evaluation.

Characterizing the gut microbiota in adults with bipolar disorder: a pilot study

Background: Convergent evidence implicates gut microbiota in human health and disease. Hitherto, relatively few studies have evaluated the gut microbiota profile in individuals with bipolar disorder (BD) relative to healthy controls (HC). Methods: Fecal samples were collected from subjects (aged 18-65) meeting DSM-5-defined criteria for BD and age- and sex-matched HC without current or past history of mental or major medical disorders. Samples were sequenced using Illumina sequencing and association of specific taxa and co-occurrence of taxa with sample groups including the effect of diet was assessed using cluster analysis and analysis of communities of microorganisms (ANCOM). Nutritional composition was evaluated using the Dietary Questionnaire for Epidemiological Studies (DQES v2) Food Frequency Questionnaire. Results: Forty-six subjects were enrolled (n=23 BD, n=23 HC). Cluster analyses did not identify any significant differences between BD and HC (p=0.38). Lower microbiota diversity was observed among BD subjects relative to HC (p=0.04). A greater abundance of a Clostridiaceae OTU was observed among BD subjects when compared to HC and of Collinsella among BD-II subjects relative to BD-I. Cluster analysis revealed that neither diagnosis (p=0.38) nor diet (p=0.43) had a significant effect on overall gut microbiota composition. Limitations: This study has a small sample size and insufficient control for some potential moderating factors (e.g. psychotropic medication and smoking). Conclusion: This study suggests that individuals with BD may have a distinct gut microbiota profile compared to healthy controls, with a greater abundance of Clostridiaceae and Collinsella. These findings need to be replicated in future studies with larger sample sizes.