Gut microbiota composition links to variation in functional domains across psychiatric disorders.

OBJECTIVE: Changes in microbial composition are observed in various psychiatric disorders, but their specificity to certain symptoms or processes remains unclear. This study explores the associations between the gut microbiota composition and the Research Domain Criteria (RDoC) domains of functioning, representing symptom domains, specifically focusing on stress-related and neurodevelopmental disorders in patients with and without psychiatric comorbidity. METHODS: The gut microbiota was analyzed in 369 participants, comprising 272 individuals diagnosed with a mood disorder, anxiety disorder, attention deficit/hyperactivity disorder, autism spectrum disorder, and/or substance use disorder, as well as 97 psychiatrically unaffected individuals. The RDoC domains were estimated using principal component analysis (PCA) with oblique rotation on a range of psychiatric, psychological, and personality measures. Associations between the gut microbiota and the functional domains were assessed using multiple linear regression and permanova, adjusted for age, sex, diet, smoking, medication use and comorbidity status. RESULTS: Four functional domains, aligning with RDoC's negative valence, social processes, cognitive systems, and arousal/regulatory systems domains, were identified. Significant associations were found between these domains and eight microbial genera, including associations of negative valence with the abundance of the genera Sellimonas, CHKCI001, Clostridium sensu stricto 1, Oscillibacter, and Flavonifractor; social processes with Sellimonas; cognitive systems with Sporobacter and Hungatella; and arousal/regulatory systems with Ruminococcus torques (all pFDR < 0.05). CONCLUSION: Our findings demonstrate associations between the gut microbiota and the domains of functioning across patients and unaffected individuals, potentially mediated by immune-related processes. These results open avenues for microbiota-focused personalized interventions, considering psychiatric comorbidity. However, further research is warranted to establish causality and elucidate mechanistic pathways.

The effectiveness of peer support for individuals with mental illness: systematic review and meta-analysis.

BACKGROUND: The benefits of peer support interventions (PSIs) for individuals with mental illness are not well known. The aim of this systematic review and meta-analysis was to assess the effectiveness of PSIs for individuals with mental illness for clinical, personal, and functional recovery outcomes. METHODS: Searches were conducted in PubMed, Embase, and PsycINFO (December 18, 2020). Included were randomized controlled trials (RCTs) comparing peer-delivered PSIs to control conditions. The quality of records was assessed using the Cochrane Collaboration Risk of Bias tool. Data were pooled for each outcome, using random-effects models. RESULTS: After screening 3455 records, 30 RCTs were included in the systematic review and 28 were meta-analyzed (4152 individuals). Compared to control conditions, peer support was associated with small but significant post-test effect sizes for clinical recovery, g = 0.19, 95% CI (0.11-0.27), I2 = 10%, 95% CI (0-44), and personal recovery, g = 0.15, 95% CI (0.04-0.27), I2 = 43%, 95% CI (1-67), but not for functional recovery, g = 0.08, 95% CI (-0.02 to 0.18), I2 = 36%, 95% CI (0-61). Our findings should be considered with caution due to the modest quality of the included studies. CONCLUSIONS: PSIs may be effective for the clinical and personal recovery of mental illness. Effects are modest, though consistent, suggesting potential efficacy for PSI across a wide range of mental disorders and intervention types.

Working it out: can an acute exercise bout alleviate memory bias, rumination and negative mood?

Although it is well known that exercise reduces depressive symptoms, the underlying psychological mechanisms remain unclear. This experimental study examined the acute effect of exercise on mood, and depressotypic memory bias and state rumination. Trait rumination was tested as a possible moderator. A sample of non-regular exercisers (N = 100) was randomized to exercise or rest. After a negative mood induction, the exercise condition cycled for 24 min at moderate intensity, while the rest condition rested. Negative and overgeneral memory bias, as well as positive and negative affect were assessed after exercise/rest. To capture the lingering of negative mood and state rumination, both were assessed multiple times throughout the study. The exercise (as compared to rest) condition reported more positive affect. However, no differences were found on overgeneral memory bias, as well as depression-specific mood or state rumination measured throughout the study. Interestingly, the exercise condition showed more negative memory bias at higher levels of rumination. Individual differences in trait rumination moderated the exercise-memory bias relation, such that exercise increased negative memory bias at higher levels of rumination. It is possible that long-term exercise protocols are necessary to change cognitive processes related to depression.

Challenging the negative learning bias hypothesis of depression: reversal learning in a naturalistic psychiatric sample.

BACKGROUND: Classic theories posit that depression is driven by a negative learning bias. Most studies supporting this proposition used small and selected samples, excluding patients with comorbidities. However, comorbidity between psychiatric disorders occurs in up to 70% of the population. Therefore, the generalizability of the negative bias hypothesis to a naturalistic psychiatric sample as well as the specificity of the bias to depression, remain unclear. In the present study, we tested the negative learning bias hypothesis in a large naturalistic sample of psychiatric patients, including depression, anxiety, addiction, attention-deficit/hyperactivity disorder, and/or autism. First, we assessed whether the negative bias hypothesis of depression generalized to a heterogeneous (and hence more naturalistic) depression sample compared with controls. Second, we assessed whether negative bias extends to other psychiatric disorders. Third, we adopted a dimensional approach, by using symptom severity as a way to assess associations across the sample. METHODS: We administered a probabilistic reversal learning task to 217 patients and 81 healthy controls. According to the negative bias hypothesis, participants with depression should exhibit enhanced learning and flexibility based on punishment v. reward. We combined analyses of traditional measures with more sensitive computational modeling. RESULTS: In contrast to previous findings, this sample of depressed patients with psychiatric comorbidities did not show a negative learning bias. CONCLUSIONS: These results speak against the generalizability of the negative learning bias hypothesis to depressed patients with comorbidities. This study highlights the importance of investigating unselected samples of psychiatric patients, which represent the vast majority of the psychiatric population.

The Role of Perseverative Cognition for Both Mental and Somatic Disorders in a Naturalistic Psychiatric Patient Sample.

OBJECTIVE: Perseverative cognition (PC) is the repeated or long-term activation of the cognitive representation of psychological stressors and is associated with prolonged stress including somatic and mental consequences. Hence, PC might represent a cognitive process linking mental and somatic pathology, but current research on this link is limited by investigating healthy samples, markers of somatic disease, and single disorders. The present study explored the importance of PC for different mental and somatic disorders in psychiatric patients. METHODS: Data from 260 naturalistic psychiatric outpatients were used. Psychiatric diagnoses were based on structured clinical interviews. Somatic diseases were assessed using a well-validated questionnaire and were clustered into (cardio)vascular and immune/endocrine diseases. PC was operationalized using the Perseverative Thinking Questionnaire (PTQ). RESULTS: Multiple regression complemented with relative importance analyses showed that the PTQ total and subscale scores were associated with the presence of mood disorders, addiction, and anxiety. Unexpectedly, no relatively important associations were found between the PTQ and autism spectrum disorder, attention-deficit/hyperactivity disorder, or somatic disease. CONCLUSIONS: Our data complement previous work linking PC to stress-related mental disorders but question its immediate role in neurodevelopmental and somatic disorders. Targeting PC in the treatment of mood disorders and perhaps also in addiction seems promising.

A randomized controlled trial of cognitive control training (CCT) as an add-on treatment for late-life depression: a study protocol.

BACKGROUND: Already a major health concern, late-life depression (LLD) is expected to form an increasing problem in the aging population. Moreover, despite current treatments, LLD is associated with a poor long-term prognosis and high rate of chronicity. Treatment provision and treatment accordingly warrant improvement, where add-on treatments might contribute to the efficacy of conventional therapies. Although it is known that impaired cognitive control contributes to LDD, it is not targeted sufficiently by current interventions. Research on cognitive control training (CCT) shows promising results on depressive symptoms, cognitive performance, and overall functioning. However, further research is needed to determine the long-term effects of CCT on LLD, its cost-effectiveness, and mechanisms of change. METHODS: In the current multicenter randomized controlled trial (RCT) with a between-subjects design participants aged 60 years and over with a current LLD receiving treatment as usual (TAU) are randomized to add-on CCT or placebo training. Randomization is stratified by depression severity. Participants will receive eight online CCT or placebo sessions spread across four consecutive weeks. They will complete a post-training assessment after 1 month and three follow-up assessments scheduled three, six and 12 months after completing the training. We expect CCT and TAU to be more (cost-)effective in reducing depressive symptoms than placebo training and TAU. Additionally, we will be looking at secondary clinical, cognitive and global functioning outcomes and likely mechanisms of change (e.g., improved cognitive functioning, reduced rumination, and improved inhibition of negative stimuli). DISCUSSION: The proposed RCT aims to contribute to the clinical and scientific knowledge on the long-term effects of CCT as an add-on treatment for LLD. Cost-effectiveness is particularly relevant considering the expected volume of the target demographic. The study will be a pragmatic trial with few inclusion restrictions, providing information on feasibility of web-based trainings in clinical settings. The outcomes are potentially generalizable to guidelines for treatment of LLD. TRIAL REGISTRATION: This trial is registered in the Netherlands Trial Register (code: NL7639 ). Registered 3 april 2019.

A Newly Developed Online Peer Support Community for Depression (Depression Connect): Qualitative Study.

BACKGROUND: Internet support groups enable users to provide peer support by exchanging knowledge about and experiences in coping with their illness. Several studies exploring the benefits of internet support groups for depression have found positive effects on recovery-oriented values, including empowerment. However, to date, little attention has been paid to user narratives. OBJECTIVE: This study aims to capture the user perspective on an online peer support community for depression with a focus on the modes of user engagement and the benefits users derive from participation in the forum. METHODS: In this qualitative study, we conducted 15 semistructured interviews with users of Depression Connect, a newly developed online peer support community for individuals with depression. Combining a concept-driven and a data-driven approach, we aimed to gain insight into what users value in our Depression Connect platform and whether and how the platform promotes empowerment. We performed a thematic analysis to explore the merits and demerits reported by users by using theoretical concepts widely used in internet support group research. In the subsequent data-driven analysis, we sought to understand the relationship between different styles of user engagement and the participants' experiences with the use of Depression Connect. Data analysis consisted of open, axial, and selective coding. To include as diverse perspectives as possible, we opted for purposive sampling. To verify and validate the (interim) results, we included negative cases and performed member checks. RESULTS: We found participation in Depression Connect contributes to a sense of belonging, emotional growth, self-efficacy, and empowerment. "Getting too caught up" was the most frequently reported negative aspect of using Depression Connect. The deployment and development of three participation styles (ie, reading, posting, and responding) affected the perceived benefits of Depression Connect use differentially, where the latter style was central to enhancing empowerment. "Being of value to others" boosted the users' belief in their personal strength. Finally, Depression Connect was predominantly used to supplement offline support and care for depression, and it mainly served as a safe environment where members could freely reflect on their coping mechanisms for depression and exchange and practice coping strategies. CONCLUSIONS: Our findings shed new light on user engagement processes on which internet support groups rely. The online community primarily served as a virtual meeting place to practice (social) skills for deployment in the offline world. It also allowed the members to learn from each other's knowledge and experiences and explore newly gained insights and coping skills.

An exploration of the conditions for deploying self-management strategies: a qualitative study of experiential knowledge in depression.

BACKGROUND: Living with recurrent, and/or chronic depression requires long-term management in addition to active coping on a day-to-day basis. Previous research on long-term management, and coping with depression mainly focused on identifying self-management strategies. However, research on the conditions for deploying self-management strategies in depression is lacking. By means of exploring the development of experiential knowledge in depression, and its relation with coping with depression, this study aims to gain insight into the conditions for deploying self-management strategies. METHODS: In the current qualitative study, individual pathways to recovery, living with depression, and recurrence risk were assessed, including but not limited to long-term management. 'Experiential knowledge', which can be defined as patients' unique knowledge and own lived experiences in facilitating and debilitating factors in the recovery process and coping with the disorder, was used as a sensitizing concept. Thirteen semi-structured interviews were conducted with individuals who experienced at least two depressive episodes and were currently in (partial) remission, plus two deviant cases were interviewed to check for saturation. Until saturation was achieved, participants were purposively selected to include diverse perspectives on coping with depression. Data were analysed using a narrative research method. RESULTS: The results show that deploying self-management strategies are an integral part of 'experiential knowledge'. The evolvement of experiential knowledge can be seen as a cyclical process of the main themes that were identified as relevant when coping with depression: introspection, empowerment, self-management strategies, and external moderators of the environment. The identification of supporting and impeding factors in coping with depression from a patient perspective might increase a sustainable use of self-management strategies. CONCLUSION: These results highlight the need for an individualised holistic model of coping with depression, both in research, and in practice. By means of integrating experiential knowledge in this holistic approach, the conditions for deployment of self-management strategies in depressive patients can be specified.

Exercise enhances: study protocol of a randomized controlled trial on aerobic exercise as depression treatment augmentation.

BACKGROUND: Major depressive disorder (MDD) is a considerable public health concern. In spite of evidence-based treatments for MDD, many patients do not improve and relapse is common. Therefore, improving treatment outcomes is much needed and adjunct exercise treatment may have great potential. Exercise was shown to be effective as monotherapy for depression and as augmentation strategy, with evidence for increasing neuroplasticity. Data on the cost-effectiveness and the long-term effects of adjunct exercise treatment are missing. Similarly, the cognitive pathways toward remission are not well understood. METHODS: The present study is designed as a multicenter randomized superiority trial in two parallel groups with follow-up assessments up to 15 months. Currently depressed outpatients (N = 120) are randomized to guideline concordant Standard Care (gcSC) alone or gcSC with adjunct exercise treatment for 12 weeks. Randomization is stratified by gender and setting, using a four, six, and eight block design. Exercise treatment is offered in accordance with the NICE guidelines and empirical evidence, consisting of one supervised and two at-home exercise sessions per week at moderate intensity. We expect that gcSC with adjunct exercise treatment is more (cost-)effective in decreasing depressive symptoms compared to gcSC alone. Moreover, we will investigate the effect of adjunct exercise treatment on other health-related outcomes (i.e. functioning, fitness, physical activity, health-related quality of life, and motivation and energy). In addition, the mechanisms of change will be studied by exploring any change in rumination, self-esteem, and memory bias as possible mediators between exercise treatment and depression outcomes. DISCUSSION: The present trial aims to inform the scientific and clinical community about the (cost-)effectiveness and psychosocial mechanisms of change of adjunct exercise treatment when implemented in the mental health service setting. Results of the present study may improve treatment outcomes in MDD and facilitate implementation of prescriptive exercise treatment in outpatient settings. TRIAL REGISTRATION: This trial is registered within the Netherlands Trial Register (code: NL8432 , date: 6th March, 2020).

Effect of cognitive bias modification-memory on depressive symptoms and autobiographical memory bias: two independent studies in high-ruminating and dysphoric samples.

Memory bias is a risk factor for depression. In two independent studies, the efficacy of one CBM-Memory session on negative memory bias and depressive symptoms was tested in vulnerable samples. We compared positive to neutral (control) CBM-Memory trainings in highly-ruminating individuals (N = 101) and individuals with elevated depressive symptoms (N = 100). In both studies, participants studied positive, neutral, and negative Swahili words paired with their translations. In five study-test blocks, they were then prompted to retrieve either only the positive or neutral translations. Immediately following the training and one week later, we tested cued recall of all translations and autobiographical memory bias; and also measured mood, depressive symptoms, and rumination. Retrieval practice resulted in training-congruent recall both immediately after and one week after the training. Overall, there was no differential decrease in symptoms or difference in autobiographical memory bias between the training conditions. In the dysphoric but not in the high-ruminating sample, the positive training resulted in positive autobiographical bias only in dysphoric individuals with positive pre-existing bias. We conclude that one session of positive retrieval-based CBM-Memory may not be enough to yield symptom change and affect autobiographical memory bias in vulnerable individuals.

Mindfulness-based cognitive therapy for patients with chronic, treatment-resistant depression: A pragmatic randomized controlled trial.

BACKGROUND: Chronic and treatment-resistant depressions pose serious problems in mental health care. Mindfulness-based cognitive therapy (MBCT) is an effective treatment for remitted and currently depressed patients. It is, however, unknown whether MBCT is effective for chronic, treatment-resistant depressed patients. METHOD: A pragmatic, multicenter, randomized-controlled trial was conducted comparing treatment-as-usual (TAU) with MBCT + TAU in 106 chronically depressed outpatients who previously received pharmacotherapy (≥4 weeks) and psychological treatment (≥10 sessions). RESULTS: Based on the intention-to-treat (ITT) analysis, participants in the MBCT + TAU condition did not have significantly fewer depressive symptoms than those in the TAU condition (-3.23 [-6.99 to 0.54], d = 0.35, P = 0.09) at posttreatment. However, compared to TAU, the MBCT + TAU group reported significantly higher remission rates (χ2 (2) = 4.25, φ = 0.22, P = 0.04), lower levels of rumination (-3.85 [-7.55 to -0.15], d = 0.39, P = 0.04), a higher quality of life (4.42 [0.03-8.81], d = 0.42, P = 0.048), more mindfulness skills (11.25 [6.09-16.40], d = 0.73, P < 0.001), and more self-compassion (2.91 [1.17-4.65], d = 0.64, P = 0.001). The percentage of non-completers in the MBCT + TAU condition was relatively high (n = 12, 24.5%). Per-protocol analyses revealed that those who completed MBCT + TAU had significantly fewer depressive symptoms at posttreatment compared to participants receiving TAU (-4.24 [-8.38 to -0.11], d = 0.45, P = 0.04). CONCLUSION: Although the ITT analysis did not reveal a significant reduction in depressive symptoms of MBCT + TAU over TAU, MBCT + TAU seems to have beneficial effects for chronic, treatment-resistant depressed patients in terms of remission rates, rumination, quality of life, mindfulness skills, and self-compassion. Additionally, patients who completed MBCT showed significant reductions in depressive symptoms. Reasons for non-completion should be further investigated.

A randomized controlled trial of Mindfulness-Based Cognitive Therapy (MBCT) versus treatment-as-usual (TAU) for chronic, treatment-resistant depression: study protocol.

BACKGROUND: Major depression is a common psychiatric disorder, frequently taking a chronic course. Despite provision of evidence-based treatments, including antidepressant medication and psychological treatments like cognitive behavioral therapy or interpersonal therapy, a substantial amount of patients do not recover. Mindfulness-Based Cognitive Therapy (MBCT) has been found to be effective in reducing relapse in recurrent depression, as well as lowering symptom levels in acute depression. The effectiveness of MBCT for chronic, treatment-resistant depression has only be studied in a few pilot trials. A large randomized controlled trial is necessary to examine the effectiveness of MBCT in reducing depressive symptoms in chronic, treatment-resistant depression. METHODS/DESIGN: A randomized-controlled trial is conducted to compare MBCT with treatment-as-usual (TAU). Patients with chronic, treatment-resistant depression who have received antidepressant medication and cognitive behavioral therapy or interpersonal therapy are included. Assessments take place at baseline and post intervention/TAU-period. The primary outcome are depressive symptoms. Secondary outcomes are: remission rates, quality of life, rumination, mindfulness skills and self-compassion. Patients in the TAU condition are offered to participate in the MBCT after the post TAU-period assessment. From all completers of the MBCT (MBCT condition and patients participating after the TAU-period), follow-up assessments are taken at three and six months after the completion of the MBCT. DISCUSSION: This trial will result in valuable information about the effectiveness of MBCT in chronic, treatment-resistant depressed patients who previously received antidepressant medication and psychological treatment. TRIAL REGISTRATION: trialregister.nl NTR4843, registered 14th October 2014.

Autistic and non-autistic individuals show the same amygdala activity during emotional face processing.

BACKGROUND: Autistic and non-autistic individuals often differ in how they perceive and show emotions, especially in their ability and inclination to infer other people's feelings from subtle cues like facial expressions. Prominent theories of autism have suggested that these differences stem from alterations in amygdala functioning and that amygdala hypoactivation causes problems with emotion recognition. Thus far, however, empirical investigations of this hypothesis have yielded mixed results and largely relied on relatively small samples. METHODS: In a sample of 72 autistic and 79 non-autistic participants, we conducted a study in which we used the Hariri paradigm to test whether amygdala activation during emotional face processing is altered in autism spectrum disorder, and whether common mental disorders like depression, ADHD or anxiety disorders influence any potential alterations in activation patterns. RESULTS: We found no evidence for differences in amygdala activation, neither when comparing autistic and non-autistic participants, nor when taking into account mental disorders or the overall level of functional impairment. LIMITATIONS: Because we used one basic emotion processing task in a Dutch sample, results might not generalise to other tasks and other populations. CONCLUSIONS: Our results challenge the view that autistic and non-autistic processing of emotional faces in the amygdala is vastly different and call for a more nuanced view of differences between non-autistic and autistic emotion processing.

Towards implementation of cognitive bias modification in mental health care: State of the science, best practices, and ways forward.

Cognitive bias modification (CBM) has evolved from an experimental method testing cognitive mechanisms of psychopathology to a promising tool for accessible digital mental health care. While we are still discovering the conditions under which clinically relevant effects occur, the dire need for accessible, effective, and low-cost mental health tools underscores the need for implementation where such tools are available. Providing our expert opinion as Association for Cognitive Bias Modification members, we first discuss the readiness of different CBM approaches for clinical implementation, then discuss key considerations with regard to implementation. Evidence is robust for approach bias modification as an adjunctive intervention for alcohol use disorders and interpretation bias modification as a stand-alone intervention for anxiety disorders. Theoretical predictions regarding the mechanisms by which bias and symptom change occur await further testing. We propose that CBM interventions with demonstrated efficacy should be provided to the targeted populations. To facilitate this, we set a research agenda based on implementation frameworks, which includes feasibility and acceptability testing, co-creation with end-users, and collaboration with industry partners.

How context, mood, and emotional memory interact in depression: A study in everyday life.

Cognitive theories of depression hold that negative contextual triggers (e.g., stressful events) induce more negative and less positive mood, in turn instigating negatively biased memories. However, context-related variability in mood and emotional memory has received insufficient attention, while the dynamic interaction between these factors plays a crucial role in the kindling of new depressive episodes. Experience Sampling Method (ESM) for repeated, daily life measures of context, mood, and autobiographic emotional memory was used in 46 currently depressed, 90 remitted-depressed, and 55 never-depressed individuals. Currently depressed individuals showed strongest negative processing style and never-depressed most positive, with remitted-depressed patients scoring intermediate. The moderated mediation model indicated that context appraisal had a direct effect on the appraisal of the recalled event (i.e., our operationalization of emotional memory), which was mediated by positive (but hardly by negative) mood and was independent of depression status. This mediation strength was relatively similar to the strength of the direct effect of context on memory. Results are in line with cognitive theories of depression. Especially context seems important for emotional memory. The association between context, mood, and memory, however, may be independent of depression status. Yet, the "level" of mood, context, and event appraisal does depend on depression status. (PsycInfo Database Record (c) 2023 APA, all rights reserved).

A transdiagnostic view on MDD and ADHD: shared cognitive characteristics?

BACKGROUND: Major Depressive disorder (MDD) and Attention Deficit Hyperactivity Disorder (ADHD) are prevalent mental disorders that often co-occur. There is overlap in symptomatology between MDD and ADHD that complicates diagnostics and treatment selection. Hence, to aid diagnostics of single and comorbid disorders, we aimed to examine the discriminative power of common symptom measures and cognitive dysfunction to differentiate between participants diagnosed with MDD, ADHD, ADHD and comorbid MDD and without a mental disorder. METHODS: Four diagnosed groups were compared: MDD (n = 103), ADHD (n = 78), comorbid MDD + ADHD (n = 29), healthy controls (HC; n = 123). We examined between-group differences and discriminative functions of clinically validated self-report symptom questionnaires, as well as task-based and self-report measures of cognitive dysfunction. RESULTS: Based on the between group comparisons, all patient groups were characterized by clinically relevant levels of ADHD-symptomatology, executive dysfunction, and diminished cognitive performances in the domain of attention; even the MDD-only group. In addition, based on self-reported symptoms of MDD, ADHD, and executive dysfunction, discriminant function analysis classified all HC correctly (100%) and patients diagnosed with ADHD or MDD relatively well (resp. 85% and 82%). Comorbid MDD + ADHD was poorly differentiated from single MDD or ADHD by the commonly used self-report symptom questionnaires for MDD and ADHD (0% correct predictions), which substantially improved by incorporating the questionnaire on executive functioning (42% correct predictions). CONCLUSIONS: In both MDD and ADHD, clinical levels of attentional and executive dysfunction were found, while these clinical groups differed in cognitive flexibility, initiating, inhibition and meta-cognition. Comorbid MDD + ADHD was poorly distinguishable from non-comorbid MDD and ADHD based on self-reported symptoms of depression and ADHD. Addition of subjective executive function in the discrimination models resulted in increased discriminative power. Our findings indicate that executive functioning measure can improve the diagnostic process of ADHD and MDD.

Follow-up outcomes of Mindfulness-Based Cognitive Therapy (MBCT) for patients with chronic, treatment-resistant depression.

BACKGROUND: Mindfulness-based cognitive therapy (MBCT) is an evidence-based treatment for depression. The current study focused on the long-term outcomes of MBCT for chronically, treatment-resistant depressed patients during a 6-months follow-up period. Additionally, predictors of treatment outcomes were explored. METHOD: The outcomes of MBCT on depressive symptoms, remission rates, quality of life, rumination, mindfulness skills and self-compassion were investigated in a cohort of chronically, treatment-resistant depressed outpatients (N = 106), who had taken part in an RCT comparing MBCT with treatment-as-usual (TAU). Measures were assessed pre-MBCT, post-MBCT, at 3-months follow-up, and at 6-months follow-up. RESULTS: Results of linear mixed effect models and Bayesian repeated measures ANOVA's reveal that depressive symptoms, quality of life, rumination, mindfulness skills and self-compassion consolidated during follow-up. Remission rates even further increased over the course of follow-up. When controlling for symptoms at baseline, higher baseline levels of rumination predicted lower depressive symptoms and quality of life at 6-month follow-up. No other predictors (i.e. duration of current depressive episode, level of treatment-resistance, childhood trauma, mindfulness skills, self-compassion) were found. LIMITATIONS: All participants received MBCT, therefore time or other non-specific effects might have influenced the results and replication studies including a control conditions are needed. CONCLUSIONS: Results indicate that the clinical benefits of MBCT for chronically, treatment-resistant depressed patients persist up to 6 months after completing MBCT. Duration of the current episode, level of treatment-resistance, childhood trauma and baseline levels of mindfulness skills and self-compassion did not predict treatment outcome. When controlling for baseline depressive symptoms participants with high levels of rumination seem to benefit more; however more research is needed. TRIAL REGISTRY: Dutch Trial Registry, number NTR4843.

Brain structure and function link to variation in biobehavioral dimensions across the psychopathological continuum.

In line with the Research Domain Criteria (RDoC) , we set out to investigate the brain basis of psychopathology within a transdiagnostic, dimensional framework. We performed an integrative structural-functional linked independent component analysis to study the relationship between brain measures and a broad set of biobehavioral measures in a sample (n = 295) with both mentally healthy participants and patients with diverse non-psychotic psychiatric disorders (i.e. mood, anxiety, addiction, and neurodevelopmental disorders). To get a more complete understanding of the underlying brain mechanisms, we used gray and white matter measures for brain structure and both resting-state and stress scans for brain function. The results emphasize the importance of the executive control network (ECN) during the functional scans for the understanding of transdiagnostic symptom dimensions. The connectivity between the ECN and the frontoparietal network in the aftermath of stress was correlated with symptom dimensions across both the cognitive and negative valence domains, and also with various other health-related biological and behavioral measures. Finally, we identified a multimodal component that was specifically associated with the diagnosis of autism spectrum disorder (ASD). The involvement of the default mode network, precentral gyrus, and thalamus across the different modalities of this component may reflect the broad functional domains that may be affected in ASD, like theory of mind, motor problems, and sensitivity to sensory stimuli, respectively. Taken together, the findings from our extensive, exploratory analyses emphasize the importance of a dimensional and more integrative approach for getting a better understanding of the brain basis of psychopathology.

Unpacking the functional heterogeneity of the Emotional Face Matching Task: a normative modelling approach.

Functional neuroimaging has contributed substantially to understanding brain function but is dominated by group analyses that index only a fraction of the variation in these data. It is increasingly clear that parsing the underlying heterogeneity is crucial to understand individual differences and the impact of different task manipulations. We estimate large-scale (N=7728) normative models of task-evoked activation during the Emotional Face Matching Task, which enables us to bind heterogeneous datasets to a common reference and dissect heterogeneity underlying group-level analyses. We apply this model to a heterogenous patient cohort, to map individual differences between patients with one or more mental health diagnoses relative to the reference cohort and determine multivariate associations with transdiagnostic symptom domains. For the face>shapes contrast, patients have a higher frequency of extreme deviations which are spatially heterogeneous. In contrast, normative models for faces>baseline have greater predictive value for individuals' transdiagnostic functioning.

The gut-microbiome in adult Attention-deficit/hyperactivity disorder - A Meta-analysis.

Attention-deficit/hyperactivity disorder (ADHD) is a common neurodevelopmental condition that persists into adulthood in the majority of individuals. While the gut-microbiome seems to be relevant for ADHD, the few publications on gut-microbial alterations in ADHD are inconsistent, in the investigated phenotypes, sequencing method/region, preprocessing, statistical approaches, and findings. To identify gut-microbiome alterations in adult ADHD, robust across studies and statistical approaches, we harmonized bioinformatic pipelines and analyses of raw 16S rRNA sequencing data from four adult ADHD case-control studies (N ADHD =312, N NoADHD =305). We investigated diversity and differential abundance of selected genera (logistic regression and ANOVA-like Differential Expression tool), corrected for age and sex, and meta-analyzed the study results. Converging results were investigated for association with hyperactive/impulsive and inattentive symptoms across all participants. Beta diversity was associated with ADHD diagnosis but showed significant heterogeneity between cohorts, despite harmonized analyses. Several genera were robustly associated with adult ADHD; e.g., Ruminococcus_torques_group (LogOdds=0.17, p fdr =4.42×10 -2 ), which was more abundant in adults with ADHD, and Eubacterium_xylanophilum_group (LogOdds= -0.12, p fdr =6.9 x 10 -3 ), which was less abundant in ADHD. Ruminococcus_torques_group was further associated with hyperactivity/impulsivity symptoms and Eisenbergiella with inattention and hyperactivity/impulsivity (p fdr <0.05). The literature points towards a role of these genera in inflammatory processes. Irreproducible results in the field of gut-microbiota research, due to between study heterogeneity and small sample sizes, stress the need for meta-analytic approaches and large sample sizes. While we robustly identified genera associated with adult ADHD, that might overall be considered beneficial or risk-conferring, functional studies are needed to shed light on these properties.