Factors Associated with Respiratory Health and Function in Duchenne Muscular Dystrophy: A Systematic Review and Evidence Grading

BACKGROUND

Despite advances in the medical management of the disease, respiratory involvement remains a significant source of morbidity and mortality in children and adults with Duchenne muscular dystrophy (DMD).

OBJECTIVE

The objective of this systematic literature review was to synthesize and grade published evidence of factors associated with respiratory health and function in DMD.

METHODS

We searched MEDLINE, Embase, and the Cochrane Library for records of studies published from January 1, 2000 (to ensure relevance to current care practices), up until and including December 31, 2022, reporting evidence of prognostic indicators and predictors of disease progression in DMD. The quality of evidence (i.e., very low to high) was assessed using the Grading of Recommendations, Assessment, Development and Evaluations (GRADE) framework.

RESULTS

The bibliographic search strategy resulted in the inclusion of 29 articles. In total, evidence of 10 factors associated with respiratory health and function in patients with DMD was identified: glucocorticoid exposure (high- to very low-quality evidence), DMD mutations (low-quality evidence), DMD genetic modifiers (low-quality evidence), other pharmacological interventions (i.e., ataluren, eteplirsen, idebenone, and tamoxifen) (moderate- to very low-quality evidence), body mass index and weight (low-quality evidence), and functional ability (low-quality evidence).

CONCLUSIONS

In conclusion, we identified a total of 10 factors associated with respiratory health in function in DMD, encompassing both pharmacological therapies, genetic mutations and modifiers, and patient clinical characteristics. Yet, more research is needed to further delineate sources of respiratory heterogeneity, in particular the genotype-phenotype association and the impact of novel DMD therapies in a real-world setting. Our synthesis and grading should be helpful to inform clinical practice and future research of this heavily burdened patient population.

Global survival trends for brain tumors, by histology: analysis of individual records for 556,237 adults diagnosed in 59 countries during 2000-2014 (CONCORD-3)

BACKGROUND

Survival is a key metric of the effectiveness of a health system in managing cancer. We set out to provide a comprehensive examination of worldwide variation and trends in survival from brain tumors in adults, by histology.

METHODS

We analyzed individual data for adults (15-99 years) diagnosed with a brain tumor (ICD-O-3 topography code C71) during 2000-2014, regardless of tumor behavior. Data underwent a 3-phase quality control as part of CONCORD-3. We estimated net survival for 11 histology groups, using the unbiased nonparametric Pohar Perme estimator.

RESULTS

The study included 556,237 adults. In 2010-2014, the global range in age-standardized 5-year net survival for the most common sub-types was broad: in the range 20%-38% for diffuse and anaplastic astrocytoma, from 4% to 17% for glioblastoma, and between 32% and 69% for oligodendroglioma. For patients with glioblastoma, the largest gains in survival occurred between 2000-2004 and 2005-2009. These improvements were more noticeable among adults diagnosed aged 40-70 years than among younger adults.

CONCLUSIONS

To the best of our knowledge, this study provides the largest account to date of global trends in population-based survival for brain tumors by histology in adults. We have highlighted remarkable gains in 5-year survival from glioblastoma since 2005, providing large-scale empirical evidence on the uptake of chemoradiation at population level. Worldwide, survival improvements have been extensive, but some countries still lag behind. Our findings may help clinicians involved in national and international tumor pathway boards to promote initiatives aimed at more extensive implementation of clinical guidelines.

[Neural networks and clinical efficacy of transcranial brain stimulation in psychiatry]

BACKGROUND

Non-invasive forms of brain stimulation, including transcranial magnetic stimulation and direct current stimulation, are increasingly being considered by clinicians as a somatic treatment option for psychiatric disorders.

AIM

Review article on the history, efficacy transcranial brain stimulation in psychiatric disorders and the role of neural networks for improving clinical efficacy.

METHOD

Review of scientific literature.

RESULTS

Transcranial magnetic stimulation has been proven effective for the treatment of depression, but treatment efficacy varies widely for other psychiatric disorders. Transcranial direct current stimulation is still at an experimental stage, but results suggest that using weak currents can have positive effects. Neuroscience research provides tools for improving therapeutic outcomes based on neural network approaches.

CONCLUSION

Transcranial brain stimulation grafted on network information appears to be a promising approach for enhancing therapeutic outcome in psychiatric disorders.

Predicted COVID-19 molecular effects on endometrium reveal key dysregulated genes and functions

COVID-19 exerts systemic effects that can compromise various organs and systems. Although retrospective and in-silico studies and prospective preliminary analysis have assessed the possibility of direct infection of the endometrium, there is a lack of in-depth and prospective studies on the impact of systemic disease on key endometrial genes and functions across the menstrual cycle and window of implantation. Gene expression data has been obtained from (i) healthy secretory endometrium collected from 42 women without endometrial pathologies and (ii) nasopharyngeal swabs from 231 women with COVID-19 and 30 negative controls. To predict how COVID-19-related gene expression changes impact key endometrial genes and functions, an in-silico model was developed by integrating the endometrial and COVID-19 datasets in an affected mid-secretory endometrium gene co-expression network. An endometrial validation set comprising 16 women (8 confirmed to have COVID-19 and 8 negative test controls) was prospectively collected to validate the expression of key genes. We predicted that five genes important for embryo implantation were affected by COVID-19 (downregulation of COBL, GPX3 and SOCS3, and upregulation of DOCK2 and SLC2A3). We experimentally validated these genes in COVID19 patients using endometrial biopsies during the secretory phase of the menstrual cycle. The results generally support the in-silico model predictions, suggesting that the transcriptomic landscape changes mediated by COVID-19 affect endometrial receptivity genes and key processes necessary for fertility, such as immune system function, protection against oxidative damage and development vital for embryo implantation and early development.

Identifying and optimizing human endometrial gene expression signatures for endometrial dating

STUDY QUESTION

What are the key considerations for developing an enhanced transcriptomic method for secretory endometrial tissue dating?

SUMMARY ANSWER

Multiple gene expression signature combinations can serve as biomarkers for endometrial dating, but their predictive performance is variable and depends on the number and identity of the genes included in the prediction model, the dataset characteristics and the technology employed for measuring gene expression.

WHAT IS KNOWN ALREADY

Among the new generation of transcriptomic endometrial dating (TED) tools developed in the last decade, there exists variation in the technology used for measuring gene expression, the gene makeup and the prediction model design. A detailed study, comparing prediction performance across signatures for understanding signature behaviour and discrepancies in gene content between them, is lacking.

STUDY DESIGN, SIZE, DURATION

A multicentre prospective study was performed between July 2018 and October 2020 at five different centres from the same group of clinics (Spain). This study recruited 281 patients and finally included in the gene expression analysis 225 Caucasian patients who underwent IVF treatment. After preprocessing and batch effect filtering, gene expression measurements from 217 patients were combined with artificial intelligence algorithms (support vector machine, random forest and k-nearest neighbours) allowing evaluation of different prediction models. In addition, secretory-phase endometrial transcriptomes from gene expression omnibus (GEO) datasets were analysed for 137 women, to study the endometrial dating capacity of genes independently and grouped by signatures. This provided data on the consistency of prediction across different gene expression technologies and datasets.

PARTICIPANTS/MATERIALS, SETTING, METHODS

Endometrial biopsies were analysed using a targeted TruSeq (Illumina) custom RNA expression panel called the endometrial dating panel (ED panel). This panel included 301 genes previously considered relevant for endometrial dating as well as new genes selected for their anticipated value in detecting the secretory phase. Final samples (n = 217) were divided into a training set for signature discovery and an independent testing set for evaluation of predictive performance of the new signature. In addition, secretory-phase endometrial transcriptomes from GEO were analysed for 137 women to study endometrial dating capacity of genes independently and grouped by signatures. Predictive performance among these signatures was compared according to signature gene set size.

MAIN RESULTS AND THE ROLE OF CHANCE

Testing of the ED panel allowed development of a model based on a new signature of 73 genes, which we termed 'TED' and delivers an enhanced tool for the consistent dating of the secretory phase progression, especially during the mid-secretory endometrium (3-8 days after progesterone (P) administration (P + 3-P + 8) in a hormone replacement therapy cycle). This new model showed the best predictive capacity in an independent test set for staging the endometrial tissue in the secretory phase, especially in the expected window of implantation (average of 114.5 ± 7.2 h of progesterone administered; range in our patient population of 82-172 h). Published sets of genes, in current use for endometrial dating and the new TED genes, were evaluated in parallel in whole-transcriptome datasets and in the ED panel dataset. TED signature performance was consistently excellent for all datasets assessed, frequently outperforming previously published sets of genes with a smaller number of genes for dating the endometrium in the secretory phase. Thus, this optimized set exhibited prediction consistency across datasets.

LARGE SCALE DATA

The data used in this study is partially available at GEO database. GEO identifiers GSE4888, GSE29981, GSE58144, GSE98386.

LIMITATIONS, REASONS FOR CAUTION

Although dating the endometrial biopsy is crucial for investigating endometrial progression and the receptivity process, further studies are needed to confirm whether or not endometrial dating methods in general are clinically useful and to guide the specific use of TED in the clinical setting.

WIDER IMPLICATIONS OF THE FINDINGS

Multiple gene signature combinations provide adequate endometrial dating, but their predictive performance depends on the identity of the genes included, the gene expression platform, the algorithms used and dataset characteristics. TED is a next-generation endometrial assessment tool based on gene expression for accurate endometrial progression dating especially during the mid-secretory.

STUDY FUNDING/COMPETING INTEREST(S)

Research funded by IVI Foundation (1810-FIVI-066-PD). P.D.-G. visiting scientist fellowship at Oxford University (BEFPI/2010/032) and Josefa Maria Sanchez-Reyes' predoctoral fellowship (ACIF/2018/072) were supported by a program from the Generalitat Valenciana funded by the Spanish government. A.D.-P. is supported by the FPU/15/01398 predoctoral fellowship from the Ministry of Science, Innovation and Universities (Spanish Government). D.W. received support from the NIHR Oxford Biomedical Research Centre. The authors do not have any competing interests to declare.

P–294 Mapping COVID–19 affected genes from blood in a Window of implantation co-expression network reveals a potentially compromised landscape

Study question

Could the transcriptomic and functional landscape of the window of implantation be compromised by SARS-COV–2 infection?

Summary answer

Some of the main genes and pathways involved in the window of implantation are affected in blood of COVID–19 patients and receptivity could be affected.

What is known already

There is a concern whether SARS-COV–2 can disrupt assisted reproduction treatments (ARTs) and fertility in short and long terms. In the endometrium, it was found that genes related to the viral infection (ACE2, TMPRSS2/4, CTSL/B) are involved in menstrual cycle progression, especially in the Window of Implantation (WOI). However, there are no studies describing the transcriptome changes after the infection, and the changes that could affect receptivity and embryo implantation. Currently transcriptomic datasets are publicly available regarding virus infection effects in blood. The aim of this study was to integrate these blood effects with the gene expression during the WOI.

Study design, size, duration

A public dataset with blood transcriptome of 231 female COVID–19 patients and 30 female controls was downloaded from GEO. Meanwhile, 5 transcriptomic endometrial datasets in the WOI with patients without endometrial pathologies were also retrieved (n = 44). Gene expression correlations (potential activations and inhibitions) were calculated in endometrium and filtered by blood differentially expressed genes for predicting the potential effects of COVID–19 in endometrial factor. Additionally, we discovered new endometrial genes involved in the infection repercussions.

Participants/materials, setting, methods

A gene co-expression network was built in Cytoscape with the WOI dataset [Pearson correlation = 0.65, only significant correlations; Power fit law R2 > = 0.8]. Differential expression was done for COVID–19 patients versus controls with limma and significant genes in blood were highlighted in the endometrial WOI network. Topological parameters were calculated by CytoHubba and network modules and related functions were analysed performing a Functional enrichment (BINGO). Statistical significance cut off was stablished in FDR<0.05.

Main results and the role of chance

After filtering by blood affected genes, 2051 genes were found differentially expressed in COVID–19 females in blood and mapped in the co-expression WOI network. Nine modules were highlighted being enriched in translational elongation, intracellular protein transport, endosome organization, vitamin D receptor binding, actin cytoskeleton organization, RNA splicing, among others. Important hubs in the endometrium that correlated with TMPRSS4 were: COBL, a gene that promotes formation of cell ruffles which are important or embryo adhesion (FC = –3.99, degree = 209); PKP2 (FC = –1.5, degree = 188) which could play a role in junctional plaques and knockdown in mice was reported to inhibit implantation; SOCS3, linked to unexplained infertility and pregnancy loss, (FC –4.3, degree = 177); GPX3 involved in detoxification and usually highly upregulated during WOI was downregulated (FC –3.7, degree = 173). GPX3 also correlated with CTSB. TPRC/CD45, related to unexplained pregnancy loss and concentration of NK cells, was an upregulated gene (FC = 5, degree = 161) that correlated with CTSL. Upregulated genes with main connections in the network were: SERPING1 (FC = 5), which regulates complement activation and embryo-maternal immune modulation and SMARCAD1 (FC 1.5), involved in DNA repair and heterochromatin organization.

Limitations, reasons for caution

This is an in-silico descriptive study where differentially expressed genes in blood samples of COVID–19 patients were analysed in an endometrial co-expression network context. Studying a COVID–19 infected endometrium during WOI would help to confirm the results of this study.

Wider implications of the findings: Although ACE2 has been reported as not highly expressed during the WOI, this study describes potential genes and functions very important for embryo implantation affected after SARS-COV–2 infection. These findings evidenced how SARS-COV–2 could impact the efficacy of ARTs and should be taken into consideration for further research and implications.

Trial registration number

Not applicable

The burden of heat-related mortality attributable to recent human-induced climate change

Climate change affects human health; however, there have been no large-scale, systematic efforts to quantify the heat-related human health impacts that have already occurred due to climate change. Here, we use empirical data from 732 locations in 43 countries to estimate the mortality burdens associated with the additional heat exposure that has resulted from recent human-induced warming, during the period 1991-2018. Across all study countries, we find that 37.0% (range 20.5-76.3%) of warm-season heat-related deaths can be attributed to anthropogenic climate change and that increased mortality is evident on every continent. Burdens varied geographically but were of the order of dozens to hundreds of deaths per year in many locations. Our findings support the urgent need for more ambitious mitigation and adaptation strategies to minimize the public health impacts of climate change.

Transcriptional changes through menstrual cycle reveal a global transcriptional derepression underlying the molecular mechanism involved in the window of implantation

The human endometrium is a dynamic tissue that only is receptive to host the embryo during a brief time in the middle secretory phase, called the window of implantation (WOI). Despite its importance, regulation of the menstrual cycle remains incompletely understood. The aim of this study was to characterize the gene cooperation and regulation of menstrual cycle progression, to dissect the molecular complexity underlying acquisition of endometrial receptivity for a successful pregnancy, and to provide the scientific community with detailed gene co-expression information throughout the menstrual cycle on a user-friendly web-tool database. A retrospective gene co-expression analysis was performed based on the endometrial receptivity array (ERarray) gene signature from 523 human endometrial samples collected across the menstrual cycle, including during the WOI. Gene co-expression analysis revealed the WOI as having the significantly smallest proportion of negative correlations for transcriptional profiles associated with successful pregnancies compared to other cycle stages, pointing to a global transcriptional derepression being involved in acquisition of endometrial receptivity. Regulation was greatest during the transition between proliferative and secretory endometrial phases. Further, we prioritized nuclear hormone receptors as major regulators of this derepression and proved that some genes and transcription factors involved in this process were dysregulated in patients with recurrent implantation failure. We also compiled the wealth of gene co-expression data to stimulate hypothesis-driven single-molecule endometrial studies in a user-friendly database: Menstrual Cycle Gene Co-expression Network (www.menstrualcyclegcn.com). This study revealed a global transcriptional repression across the menstrual cycle, which relaxes when the WOI opens for transcriptional profiles associated with successful pregnancies. These findings suggest that a global transcriptional derepression is needed for embryo implantation and early development.

Estimating infant mortality risk in Uruguay using artificial neural networks

Background

Uruguay has a national electronic live birth certificate that includes variables of risk factors for infant mortality. Accurate risk stratification of newborns is needed to optimize the use of resources for homes visits. Artificial neural networks are computational tools that have been used successfully in many types of prediction problems.

Objective

To develop a neural network able to estimate the risk of infant mortality using information available in the electronic live birth and mortality certificate in Uruguay.

Methods

A historical cohort of records of newborns in Uruguay from 2014 to 2017 was used. The variables of the electronic live birth certificate were considered for the model. Infant mortality was obtained from the national mortality registry. A multilayer perceptron was trained with a random sample of 70% of the cohort; the remaining 30% was the validation set. The variables included were birth weight, Apgar score at 5 minutes, number of prenatal consultations, maternal educational level, multiple pregnancy and cohabiting father. ROC curve analysis was performed.

Results

The 2014-2017 birth cohort contains 187,388 records. 1,307 children under one year died (IMR 6.97 per 1,000 births). The area under the curve (AUC) was 88.7%, 95% CI [87.6% - 89.8%]. The optimal cut-off point of pseudoprobability of infant mortality was 0.008 (78.9% of sensibility and 82.4% of specificity). The IMR in high-risk newborns identified by the neural network was 32.8 per 1,000 births.

Conclusions

The neural network identifies high-risk newborns at the time of entering the data in the electronic live birth certificate as other models have done. This information could be used to plan and implement preventive actions.

Key messages

In Uruguay, high-risk newborns can be identified by applying artificial intelligence to data collected routinely. The procedure can be applied in other countries with electronic birth certificate.

Development of an infant mortality risk score in Uruguay

Background

The Ministry of Public Health of Uruguay incorporated a comprehensive home visit before 7 days of discharge to monitor children at risk of infant mortality. In this context, a precise risk stratification of newborns is needed to optimize the implementation of the home visit.

Objective

Implement a validated infant mortality risk score for Uruguay using the national electronic live birth certificate.

Methods

Electronic records of newborns from 2014 to 2017 were used to develop the score. The variables of the electronic live birth certificate were considered for the model and data of Infant mortality was obtained from the national mortality registry. A multivariate binary logistic regression model was estimated with a random sample of 80% of the cohort, the remaining 20% was the validation set. ROC curve analysis was performed. R software was used.

Results

The 2014-2017 birth cohort contains 187,388 records. 1307 children under one year died (IMR 6.97 per 1,000 births). The variables included in the final model were birth weight, APGAR score at 5 minutes, number of prenatal visits, maternal educational level and father living at home. The area under the curve (AUC) was 89%, CI 95% [87% - 91%]. Two cut-off points were defined: 0.4% and 2%. Less than 0.4% was considered low risk (IMR 1.4 per 1,000 births), between 0.4 and 2% was considered intermediate risk (IMR 7.1 per 1,000 births) and more than 2% was considered high risk (IMR 99.2 per 1,000 births).

Conclusions

The score identifies high-risk newborns at the time of entering the data in the electronic live birth certificate. This information could be used to plan and implement the home visit and other actions, according to the level of risk identified.

Key messages

In Uruguay, high-risk newborns can be identified using data collected routinely. The procedure could be applied in other countries with electronic birth certificate.

Brain areas associated with clinical and cognitive insight in psychotic disorders: A systematic review and meta-analysis

In the past years, ample interest in brain abnormalities related to clinical and cognitive insight in psychosis has contributed several neuroimaging studies to the literature. In the current study, published findings on the neural substrates of clinical and cognitive insight in psychosis are integrated by performing a systematic review and meta-analysis. Coordinate-based meta-analyses were performed with the parametric coordinate-based meta-analysis approach, non-coordinate based meta-analyses were conducted with the metafor package in R. Papers that could not be included in the meta-analyses were systematically reviewed. Thirty-seven studies were retrieved, of which 21 studies were included in meta-analyses. Poorer clinical insight was related to smaller whole brain gray and white matter volume and gray matter volume of the frontal gyri. Cognitive insight was predominantly positively associated with structure and function of the hippocampus and ventrolateral prefrontal cortex. Impaired clinical insight is not associated with abnormalities of isolated brain regions, but with spatially diffuse global and frontal abnormalities suggesting it might rely on a range of cognitive and self-evaluative processes. Cognitive insight is associated with specific areas and appears to rely more on retrieving and integrating self-related information.

Reward Circuits and Apathy in Schizophrenia: Neuroimaging and Treatment Strategies

Approximately 50% of patients with schizophrenia shows deficits in motivation and initiation of goal-directed behavior, which are suggestive of reward system dysfunction. We conducted a meta-analysis of neuroimaging studies reporting on the neural correlates of reward processing and negative symptoms in schizophrenia. A significant mean weighted correlation was observerd, revealing deficits in activation of reward neurocircuitry. A more specific findings is comprised activation of the ventral striatum, involved in anticipation of reward, and structures that play a critical role in the ability to represent the value of outcomes and plans. In a study of VTA connectivity in the resting state in a large group of patients with schizophrenia, we found reduced connectivity with lateral prefrontal, temporal and parietal regions to be associated with higher degrees of apathy. Apathy belongs to the most debilitating symptoms of schizophrenia and represents a significant unmet need in its treatment. Quantitative integration of published findings suggests that treatment with noninvasive magnetic brain stimulation can improve negative symptoms. Previous PET-studies have shown that such stimulation may target circuits with dopaminergic innervation. A behavioral treatment approach that may also target reward-related circuits will also be discussed briefly. It can be concluded that recent results regarding reward and motivated behavior in schizophrenia have clinical implications and may help develop novel treatment strategies.

Disclosure of interest

AA received speaker fees from Lundbeck.

Auditory hallucinations, top-down processing and language perception: a general population study

BACKGROUND

Studies investigating the underlying mechanisms of hallucinations in patients with schizophrenia suggest that an imbalance in top-down expectations v. bottom-up processing underlies these errors in perception. This study evaluates this hypothesis by testing if individuals drawn from the general population who have had auditory hallucinations (AH) have more misperceptions in auditory language perception than those who have never hallucinated.

METHODS

We used an online survey to determine the presence of hallucinations. Participants filled out the Questionnaire for Psychotic Experiences and participated in an auditory verbal recognition task to assess both correct perceptions (hits) and misperceptions (false alarms). A hearing test was performed to screen for hearing problems.

RESULTS

A total of 5115 individuals from the general Dutch population participated in this study. Participants who reported AH in the week preceding the test had a higher false alarm rate in their auditory perception compared with those without such (recent) experiences. The more recent the AH were experienced, the more mistakes participants made. While the presence of verbal AH (AVH) was predictive for false alarm rate in auditory language perception, the presence of non-verbal or visual hallucinations were not.

CONCLUSIONS

The presence of AVH predicted false alarm rate in auditory language perception, whereas the presence of non-verbal auditory or visual hallucinations was not, suggesting that enhanced top-down processing does not transfer across modalities. More false alarms were observed in participants who reported more recent AVHs. This is in line with models of enhanced influence of top-down expectations in persons who hallucinate.

Decreased functional connectivity of the insula within the salience network as an indicator for prospective insufficient response to antidepressants

•

Connectivity analyses complemented with a metric exploring switching in brain activity.

•

Lower insula-salience connectivity predicts insufficient antidepressant response.

•

This same insula region is activated less when switching from task to a rest.

•

This could be a potential biomarkers for predicting future antidepressant response.

Insufficient response to treatment is the main cause of prolonged suffering from major depressive disorder (MDD). Early identification of insufficient response could result in faster and more targeted treatment strategies to reduce suffering. We therefore explored whether baseline alterations within and between resting state functional connectivity networks could serve as markers of insufficient response to antidepressant treatment in two years of follow-up. We selected MDD patients (N = 17) from the NEtherlands Study of Depression and Anxiety (NESDA), who received ≥ two antidepressants, indicative for insufficient response, during the two year follow-up, a group of MDD patients who received only one antidepressant (N = 32) and a healthy control group (N = 19) matched on clinical characteristics and demographics. An independent component analysis (ICA) of baseline resting-state scans was conducted after which functional connectivity within the components was compared between groups. We observed lower connectivity of the right insula within the salience network in the group with ≥ two antidepressants compared to the group with one antidepressant. No difference in connectivity was found between the patient groups and healthy control group. Given the suggested role of the right insula in switching between task-positive mode (activation during attention-demanding tasks) and task-negative mode (activation during the absence of any task), we explored whether right insula activation differed during switching between these two modes. We observed that in the ≥2 antidepressant group, the right insula was less active compared to the group with one antidepressant, when switching from task-positive to task-negative mode than the other way around. These findings imply that lower right insula connectivity within the salience network may serve as an indicator for prospective insufficient response to antidepressants. This result, supplemented by the diminished insula activation when switching between task and rest related networks, could indicate an underlying mechanism that, if not sufficiently targeted by current antidepressants, could lead to insufficient response. When replicated, these findings may contribute to the identification of biomarkers for early detection of insufficient response.

Measuring empathy in schizophrenia: The Empathic Accuracy Task and its correlation with other empathy measures

INTRODUCTION

Empathy is an interpersonal process impaired in schizophrenia. Past studies have mainly used questionnaires or performance-based tasks with static cues to measure cognitive and affective empathy. We used the Empathic Accuracy Task (EAT) designed to capture dynamic aspects of empathy by using videoclips in which perceivers continuously judge emotionally charged stories. We compared individuals with schizophrenia with a healthy comparison group and assessed correlations among EAT and three other commonly used empathy measures.

METHOD

Patients (n = 92) and a healthy comparison group (n = 42) matched for age, gender and education completed the EAT, the Interpersonal Reactivity Index, Questionnaire of Cognitive and Affective Empathy and Faux Pas. Differences between groups were analyzed and correlations were calculated between empathy measurement instruments.

RESULTS

The groups differed in EAT performance, with the comparison group outperforming patients. A moderating effect was found for emotional expressivity of the target: while both patients and the comparison group scored low when judging targets with low expressivity, the comparison group performed better than patients with more expressive targets. Though there were also group differences on the empathy questionnaires, EAT performance did not correlate with questionnaire scores.

CONCLUSIONS

Individuals with schizophrenia benefit less from the emotional expressivity of other people than the comparison group, which contributes to their impaired empathic accuracy. The lack of correlation between the EAT and the questionnaires suggests a distinction between self-report empathy and actual empathy performance. To explore empathic difficulties in real life, it is important to use instruments that take the interpersonal perspective into account.

Social cognitive group treatment for impaired insight in psychosis: A multicenter randomized controlled trial

PURPOSE

The majority of people with schizophrenia has impaired insight, which is related to a poorer outcome. In this study, we evaluate a new psychosocial intervention 'REFLEX' aimed at improving insight in people with schizophrenia. REFLEX focuses on targeting stigma-sensitivity, perspective taking and self-reflection in people with schizophrenia and low insight. Primary objective is to improve insight and subsequently to improve functional outcome and symptoms.

METHOD

A total of 121 people diagnosed with schizophrenia according to DSM IV criteria with impaired insight was included in 2012-2015 from seven sites in a multicenter randomized controlled trial. REFLEX was compared to an active control condition consisting of group-wise simplified cognitive remediation training. Primary outcome of the study were the preconditions of insight: internalized stigma, self-reflection, mental flexibility and perspective taking. Clinical insight and cognitive insight were secondary outcomes.

RESULTS

Although perspective taking, self-reflection, mental flexibility and stigma sensitivity remained unchanged after the intervention, results showed a significant improvement of clinical insight in both conditions directly after treatment (SAI-E Rater, p < .001, PANSS G12, p < .005) and at follow-up (SAI-E Rater, p < .01, SAI-E interview, p < .001, PANSS G12, p < .0001). Improvement of clinical insight directly after treatment was larger in the REFLEX condition (SAI-E Rater, p < .05). Other outcomes (self-esteem, quality of life and depression) remained unchanged.

CONCLUSION

Though insight improved in both conditions, REFLEX was not superior to simplified drill-and-practice cognitive remediation training. Nevertheless, this study indicates that structured interventions can significantly improve insight. Further research on the underlying mechanisms of both conditions is needed, as insight is unlikely to improve spontaneously in chronic patients.

[Consensus statement on the application of rTMS in depression in the Netherlands and Belgium]

Since 2017, repetitive transcranial magnetic stimulation (rTMS) has become eligible for reimbursement for the treatment of therapy-resistant depression in the Dutch healthcare system.<br/> AIM: To initiate a guideline in the Netherlands and Belgium for the safe and effective application of rTMS for the treatment of depression.<br/> METHOD: Based on literature review, existing guidelines and consensus among Dutch rTMS experts, recommendations were developed regarding the implementation of rTMS as a treatment of depression. All available evidence was weighed and discussed among all co-authors and recommendations were reached by consensus among the group.<br/> RESULTS: rTMS targeting the dorsolateral prefrontal cortex (DLPFC) should be seen as a first choice in the treatment of depression using high-frequency rTMS (left) or, as an alternative, low-frequency rTMS (right). Stimulation protocols should use more than 1000 pulses per session for an average of 20-30 sessions, offered in 2-5 sessions per week. Contraindications for rTMS include epilepsy, intracranial presence of (magnetisable) metals, pacemaker and cochlear implant.<br/> CONCLUSION: rTMS, performed by competent professionals is an effective and safe treatment for depression.

Metacognitive reflection and insight therapy (MERIT) for patients with schizophrenia

BACKGROUND

Impaired metacognition is associated with difficulties in the daily functioning of people with psychosis. Metacognition can be divided into four domains: Self-Reflection, Understanding the Other's Mind, Decentration, and Mastery. This study investigated whether Metacognitive Reflection and Insight Therapy (MERIT) can be used to improve metacognition.

METHODS

This study is a randomized controlled trial. Patients in the active condition (n = 35) received forty MERIT sessions, the control group (n = 35) received treatment as usual. Multilevel intention-to-treat and completers analyses were performed for metacognition and secondary outcomes (psychotic symptomatology, cognitive insight, Theory of Mind, empathy, depression, self-stigma, quality of life, social functioning, and work readiness).

RESULTS

Eighteen out of 35 participants finished treatment, half the drop-out stemmed from therapist attrition (N = 5) or before the first session (N = 4). Intention-to-treat analysis demonstrated that in both groups metacognition improved between pre- and post-measurements, with no significant differences between the groups. Patients who received MERIT continued to improve, while the control group returned to baseline, leading to significant differences at follow-up. Completers analysis (18/35) showed improvements on the Metacognition Assessment Scale (MAS-A) scales Self Reflectivity and metacognitive Mastery at follow-up. No effects were found on secondary outcomes.

CONCLUSIONS

On average, participants in the MERIT group were, based on MAS-A scores, at follow-up more likely to recognize their thoughts as changeable rather than as facts. MERIT might be useful for patients whose self-reflection is too limited to benefit from other therapies. Given how no changes were found in secondary measures, further research is needed. Limitations and suggestions for future research are discussed.

Circulating insulin-like growth factor I modulates mood and is a biomarker of vulnerability to stress: from mouse to man

Individual susceptibility to anxiety disorders after maladaptive responses to stress is not well understood. We now report that while exploring stress responses in mice after traumatic brain injury (TBI), a condition associated to stress susceptibility, we observed that the anxiogenic effects of either TBI or exposure to life-threatening experiences (predator) were blocked when both stressors were combined. Because TBI increases the entrance into the brain of serum insulin-like growth factor I (IGF-I), a known modulator of anxiety with a wide range of concentrations in the human population, we then determined whether circulating IGF-I is related to anxiety measures. In mice, anxiety-like responses to predator were inversely related to circulating IGF-I levels. Other indicators of mood regulation such as sensitivity to dexamethasone suppression and expression levels of blood and brain FK506 binding protein 5 (FKBP5), a co-chaperone of the glucocorticoid receptor that regulates its activity, were also associated to circulating IGF-I. Indeed, brain FKBP5 expression in mice was stimulated by IGF-I. In addition, we observed in a large human cohort (n = 2686) a significant relationship between plasma IGF-I and exposure to recent stressful life events, while FKBP5 expression in blood cells was significantly associated to plasma IGF-I levels. Collectively, these data indicate that circulating IGF-I appears to be involved in mood homeostasis across different species. Furthermore, the data in mice allow us to indicate that IGF-I may be acting at least in part by modulating FKBP5 expression.

Neural correlates of exercise training in individuals with schizophrenia and in healthy individuals: A systematic review

A body of evidence has revealed positive effects of physical exercise on behavioral, cognitive and physical outcomes in patients with schizophrenia. Notably, the effect of exercise at the neural level may be particularly relevant as well as it is hypothesized that exercise may stimulate the brain in a way that might normalize neural alterations related to the disorder. The aim of the current systematic review was to provide an up to date overview of studies investigating the neural effects of exercise in individuals with a schizophrenia spectrum disorder and healthy individuals. The majority of included studies focused on hippocampal effects, reporting beneficial effects of exercise. In addition, in schizophrenia increased extrastriate body area (EBA) activation and increased white matter fiber integrity in tracts relevant to the disorder were found and in healthy individuals decreased connectivity of the dorsolateral prefrontal cortex (DLPFC) indicating greater cognitive efficiency was reported. Comparing individuals with a schizophrenia spectrum disorder and healthy individuals within a similar age range, most studies found similar effects on hippocampal volume and white matter tracts for both groups, although the effect in schizophrenia spectrum disorders may be attenuated which is in line with previous literature on brain plasticity. The current review indicates a lack of studies investigating neural correlates other than the hippocampus. Although those studies that did focus on other neural correlates revealed promising results, these have not been replicated in other studies and call for replication. Furthermore, future studies should expand their focus, by investigating neural mechanisms underlying positive effects of physical exercise on positive symptoms, negative symptoms and symptoms such as depression, social withdrawal and social cognition.

[rTMS for treatment resistant depression - proposal for a treatment protocol]

At present, the use of repetitive transcranial magnetic stimulation (rtms) for treatment-resistant depression is sufficiently substantiated to be applied in clinical practice. In the Netherlands, it will be reimbursed when offered in combination with cognitive behavior therapy.<br/> AIM: Proposal for a clinical treatment protocol for rtms in The Netherlands.<br/> METHOD: A study of the literature and a critical appraisal of available international guidelines for rtms.<br/> RESULTS: rtms is a safe treatment for patients suffering from a moderate to severe depressive disorder that is relatively treatment-resistant. The duration of the effect is still unknown. It is advised to stimulate the left dorsolateral prefrontal cortex using an intensity of 120% of the resting motor threshold, with a frequency of 10 Hz and using 3000 pulses per session during a total of 20-30 sessions.<br/> CONCLUSION: The proposed treatment protocol is favored based on the available evidence when rtms is used as a treatment aimed to acutely decrease the severity of depressive symptoms. It is further proposed to systematically collect technical and outcome data on treatment with rtms to further improve treatment with rtms in clinical practice.

Differential Neural Correlates of Dimensions of Negative Symptoms in Schizophrenia During Social-emotional Appraisal and Effects of Treatment

Factor analyses of large datasets have established two dimensions of negative symptoms: expressive deficits and a motivation. This distinction is of relevance as the dimensions differ in their cognitive and clinical correlates (e.g. with regard to functional outcome). Using functional MRI, we examined the neural correlates of the two negative symptom dimensions with brain activation during social-emotional evaluation. Patients with schizophrenia (n = 38) and healthy controls (n = 20) performed the Wall of Faces task during fMRI, which measures emotional ambiguity in a social context by presenting an array of faces with varying degrees of consistency in emotional expressions. More specifically, appraisal of facial expressions under uncertainty. We found severity of expressive deficits to be negatively correlated with activation in thalamic, prefrontal, precentral, parietal and temporal brain areas during emotional ambiguity (appraisal of facial expressions in an equivocal versus an unequivocal condition). No association was found for a motivation with these neural correlates, in contrast to a previous fMRI study in which we found a motivation to be associated with neural correlates of executive (planning) performance. We also evaluated the effects of medication and neurostimulation (rTMS treatment over the lateral prefrontal cortex) on activation during the social–emotional ambiguity task. The medication comparison concerned an RCT of aripiprazole versus risperidone. Compared to risperidone, aripiprazole showed differential involvement of frontotemporal and frontostriatal circuits in social-emotional ambiguity. We conclude that deconstruction of negative symptoms into more homogeneous components and investigating underlying neurocognitive mechanisms can potentially shed more light on their nature and may ultimately yield clues for targeted treatment.

Disclosure of interest

AA received speaker fees from Lundbeck.

[Non-invasive brain stimulation in schizophrenia: hallucinations and negative symptoms]

New approaches are needed in the treatment of characteristic symptoms of schizophrenia such as hallucinations and negative symptoms. Non-invasive brain stimulation can make a useful contribution.<br/> AIM: To discuss the published evidence regarding efficacy and safety of repetitive transcranial magnetic stimulation (rtms) and transcranial direct current stimulation (tdcs) when used in the treatment of auditory verbal hallucinations and negative symptoms.<br/> METHOD: We review and discuss recent meta-analyses and we analyse relevant factors.<br/> RESULTS: On average, when compared to sham-stimulation, rtms was found to have a significant effect on hallucinations and negative symptoms. Nevertheless, the results of some studies were variable and some studies did not report any improvement. There are indications that some factors such as age and distance between scalp and cortex may influence efficiency. There were only a few studies relating to the use of tdcs and none of these reported a clear effect.<br/> CONCLUSION: There is reasonable evidence that rtms is an efficient treatment for hallucinations and negative symptoms, although some variable results have been reported. There is insufficient evidence for conclusions to be drawn about the efficacy of tdcs for the treatment of hallucinations and negative symptoms. However, both simulation methods are safe and largely without side-effects.

[Brain stimulation: the most direct form of neurostimulation]

BACKGROUND

Brain stimulation is the most direct form of neuromodulation. Direct brain stimulation is an older procedure that has taken various forms, but 'non-invasive brain stimulation' is a more recent development.

AIM

To provide an overview of the current arsenal of non-invasive brain stimulation techniques.

METHOD

We discuss the underlying principles, the pros and cons, and the applicability of non-invasive brain stimulation in experimental research and treatment of neuropsychiatric disorders.

RESULTS

Non-invasive brain stimulation is a direct form of neuromodulation, which is not invasive, harmful or painful. Its effects are in principle temporary, which makes the technique suitable for experimental research. At the same time, temporary effects can have lasting clinical consequences, if they target neuroplasticity to aid rehabilitation or alleviate symptoms.

CONCLUSION

Whereas the value of non-invasive brain stimulation for research purposes is undisputed, its efficacy and value as a treatment for neuropsychiatric disorders are still being debated. Nevertheless, the accumulated evidence about the clinical efficacy of the treatment for certain disorders is sufficiently compelling to start thinking about European regulations and standard medical insurance coverage.

The prevalence of visual hallucinations in non-affective psychosis, and the role of perception and attention

BACKGROUND

Little is known about visual hallucinations (VH) in psychosis. We investigated the prevalence and the role of bottom-up and top-down processing in VH. The prevailing view is that VH are probably related to altered top-down processing, rather than to distorted bottom-up processing. Conversely, VH in Parkinson's disease are associated with impaired visual perception and attention, as proposed by the Perception and Attention Deficit (PAD) model. Auditory hallucinations (AH) in psychosis, however, are thought to be related to increased attention.

METHOD

Our retrospective database study included 1119 patients with non-affective psychosis and 586 controls. The Community Assessment of Psychic Experiences established the VH rate. Scores on visual perception tests [Degraded Facial Affect Recognition (DFAR), Benton Facial Recognition Task] and attention tests [Response Set-shifting Task, Continuous Performance Test-HQ (CPT-HQ)] were compared between 75 VH patients, 706 non-VH patients and 485 non-VH controls.

RESULTS

The lifetime VH rate was 37%. The patient groups performed similarly on cognitive tasks; both groups showed worse perception (DFAR) than controls. Non-VH patients showed worse attention (CPT-HQ) than controls, whereas VH patients did not perform differently.

CONCLUSIONS

We did not find significant VH-related impairments in bottom-up processing or direct top-down alterations. However, the results suggest a relatively spared attentional performance in VH patients, whereas face perception and processing speed were equally impaired in both patient groups relative to controls. This would match better with the increased attention hypothesis than with the PAD model. Our finding that VH frequently co-occur with AH may support an increased attention-induced 'hallucination proneness'.

Self-related networks and negative symptoms in psychotic disorders

Objective

Two factors of negative symptoms in schizophrenia have been consistently described based on factor analysis, “expressive deficits” and “social amotivation”. We aimed to investigate the putatively differential involvement of self-related networks, as measured with BOLD fMRI during a self-evaluation task, in two dimensions of negative symptoms in schizophrenia (reduced expression and social amotivation).

Method

Forty-five patients with a diagnosis of schizophrenia participated in an fMRI study in which they performed a self-evaluation task. The task comprised a self-reflection, close other-reflection, and a semantic (baseline) condition. We compared correlates of Expressive versus Social amotivation factors (summed items from the PANSS interview) for the contrasts self-baseline and self-other. Significance threshold was set at P < 0.05 family-wise error (FEW) corrected.

Results

Social amotivation correlated significantly with self-evaluation vs. baseline in right and left ACC, and in the sulcus of frontal lateral lobe between inferior frontal triangularis and middle frontal gyrus. This was also significant, but less pronounced, in the direct comparison of social amotivation vs. expressive deficits scores (for the self-baseline contrast). No activation differences survived critical thresholds for the self-other contrast.

Conclusion

Differential neural correlates for the two dimensions of negative symptoms support the validity of this distinction based on factor analyses. Intact functioning of brain circuitry for self-referential processing may be of relevance to actively seek social interaction.

Disclosure of interest

The author has not supplied his declaration of competing interest.

[Metacognition in psychotic disorders: from concepts to intervention]

BACKGROUND

Persons with a psychotic disorder commonly experience difficulties with what is considered to be metacognitive capacity. In this article we discuss several definitions of this concept, the measurement instruments involved and the clinical interventions that target this concept.

AIM

To present a review of various frequently used definitions of metacognition and related concepts and to describe the measurement instruments involved and the treatment options available for improving the metacognitive capacity of persons with a psychotic disorder.

METHOD

We present an overview of several definitions of metacognition in psychotic disorders and we discuss frequently used measurement instruments and treatment options. The article focuses on recent developments in a model devised by Semerari et al. The measurement instrument involved (Metacognition Assessment Scale - A) is discussed in terms of it being an addition to existing methods.

RESULTS

On the basis of the literature it appears that metacognition and related concepts are measurable constructs, although definitions and instruments vary considerably. The new conceptualisation of social information processing also leads to the development of a new form of psychotherapy that aims to help patients suffering from psychotic disorders to improve metacognitive capacity.

CONCLUSION

There seems to be evidence that metacognitive abilities are a possible target for treatment, but further research is needed.

Investigating distinct and common abnormalities of resting-state functional connectivity in depression, anxiety, and their comorbid states

Depression and anxiety disorders are highly comorbid and share neurobiological characteristics. However, this is usually not explicitly addressed in studies on intrinsic brain functioning in these disorders. Contrary to previous resting-state reports on small, monodiagnostic subsets of the current sample, we investigated resting-state functional connectivity (RSFC) in medication-free patients with depression, anxiety, comorbid depression and anxiety, and a healthy control group. RSFC was investigated in 140 medication-free subjects: 37 major depressive disorder patients (MDD), 30 patients with one or more anxiety disorders (ANX), 25 patients with MDD and one or more anxiety disorders (COM), and 48 healthy controls (HC). RSFC networks were calculated using a probabilistic independent component analysis. Using a dual regression approach, individuals׳ timecourses were extracted and regressed to obtain subjects-specific spatial maps, which were used for group comparisons in four networks of interest (limbic, default mode, salience and sensory-motor networks). When compared to HC, the COM group showed increased RSFC of the limbic network with a cluster containing the bilateral precuneus, intracalcarine cortex, lingual gyrus, and posterior cingulate, and with a cluster including the right precentral gyrus, inferior frontal gyrus, and middle frontal gyrus. This effect was specific for comorbid depression and anxiety. No abnormal RSFC of other networks or in the MDD and ANX groups was observed. No association was found between strength of RSFC and symptom severity. These results indicate that altered RSFC of cortical regions with a limbic network could be specific for comorbid depression and anxiety.

Differential effects of antipsychotic drugs on insight in first episode schizophrenia: Data from the European First-Episode Schizophrenia Trial (EUFEST)

Although antipsychotics are widely prescribed, their effect of on improving poor illness insight in schizophrenia has seldom been investigated and therefore remains uncertain. This paper examines the effects of low dose haloperidol, amisulpride, olanzapine, quetiapine, and ziprasidone on insight in first-episode schizophrenia, schizoaffective disorder, or schizophreniform disorder. The effects of five antipsychotic drugs in first episode psychosis on insight were compared in a large scale open randomized controlled trial conducted in 14 European countries: the European First-Episode Schizophrenia Trial (EUFEST). Patients with at least minimal impairments in insight were included in the present study (n=455). Insight was assessed with item G12 of the Positive and Negative Syndrome Scale (PANSS), administered at baseline and at 1, 3, 6, 9, and 12 months after randomization. The use of antipsychotics was associated with clear improvements in insight over and above improvements in other symptoms. This effect was most pronounced in the first three months of treatment, with quetiapine being significantly less effective than other drugs. Effects of spontaneous improvement cannot be ruled out due to the lack of a placebo control group, although such a large spontaneous improvement of insight would seem unlikely.

Efficacy of bilateral repetitive transcranial magnetic stimulation for negative symptoms of schizophrenia: results of a multicenter double-blind randomized controlled trial

BACKGROUND

Few studies have investigated the efficacy of repetitive transcranial magnetic stimulation (rTMS) treatment for negative symptoms of schizophrenia, reporting inconsistent results. We aimed to investigate whether 10 Hz stimulation of the bilateral dorsolateral prefrontal cortex during 3 weeks enhances treatment effects.

METHOD

A multicenter double-blind randomized controlled trial was performed in 32 patients with schizophrenia or schizo-affective disorder, and moderate to severe negative symptoms [Positive and Negative Syndrome Scale (PANSS) negative subscale ⩾15]. Patients were randomized to a 3-week course of active or sham rTMS. Primary outcome was severity of negative symptoms as measured with the Scale for the Assessment of Negative Symptoms (SANS) and the PANSS negative symptom score. Secondary outcome measures included cognition, insight, quality of life and mood. Subjects were followed up at 4 weeks and at 3 months. For analysis of the data a mixed-effects linear model was used.

RESULTS

A significant improvement of the SANS in the active group compared with sham up to 3 months follow-up (p = 0.03) was found. The PANSS negative symptom scores did not show a significant change (p = 0.19). Of the cognitive tests, only one showed a significant improvement after rTMS as compared with sham. Finally, a significant change of insight was found with better scores in the treatment group.

CONCLUSIONS

Bilateral 10 Hz prefrontal rTMS reduced negative symptoms, as measured with the SANS. More studies are needed to investigate optimal parameters for rTMS, the cognitive effects and the neural basis.

Insight change in psychosis: relationship with neurocognition, social cognition, clinical symptoms and phase of illness

OBJECTIVE

Impaired insight is an important and prevalent symptom of psychosis. It remains unclear whether cognitive disturbances hamper improvements in insight. We investigated the neurocognitive, social cognitive, and clinical correlates of changes in insight.

METHOD

One hundred and fifty-four patients with a psychotic disorder were assessed at baseline (T0 ) and after three years (T3 ) with the Birchwood Insight Scale, the Positive And Negative Syndrome Scale, measures of neurocognition and social cognition. Linear regression analyses were conducted to examine to what extend neurocognition, social cognition, clinical symptoms and phase of illness could uniquely predict insight change. Subsequently, changes in these factors were related to insight change.

RESULTS

Better neurocognitive performance and fewer clinical symptoms at baseline explained insight improvements. The additional effect of clinical symptoms over and above the contribution of neurocognition was significant. Together, these factors explained 10% of the variance. Social cognition and phase of illness could not predict insight change. Changes in clinical symptoms, but not changes in neurocognitive performance were associated with insight change.

CONCLUSION

Neurocognitive abilities may predict, in part, the development of insight in psychosis.

Cognitive subtypes in non-affected siblings of schizophrenia patients: characteristics and profile congruency with affected family members

BACKGROUND

Although cognitive subtypes have been suggested in schizophrenia patients, similar analyses have not been carried out in their non-affected siblings. Subtype classification may provide more insight into genetically driven variation in cognitive function. We investigated cognitive subtypes in siblings.

METHOD

Cluster analyses were performed in 654 non-affected siblings, on a cognitive battery that included tests of attention, intellectual function and episodic memory. Resulting subtypes in the siblings were analyzed for cognitive, demographic and clinical characteristics and compared with those of their probands.

RESULTS

Three sibling subtypes of cognitive function were distinguished: 'normal', 'mixed' and 'impaired'. Normal profile siblings (n = 192) were unimpaired on cognitive tests, in contrast to their proband (n = 184). Mixed profile siblings (n = 228) and their probands (n = 222) had a more similar performance pattern. Impaired profile siblings had poorer functional outcomes (n = 234) and their profile was almost identical to that of their proband (n = 223). Probands with cognitively impaired siblings could be distinguished from other schizophrenia patients by their own cognitive performance. They also had poorer clinical characteristics, including achievement of symptomatic remission.

CONCLUSIONS

Unaffected siblings of patients with schizophrenia are heterogeneous with respect to cognitive function. The poorer the cognitive profile of the sibling, the higher the level of correspondence with the proband. The sibling's cognitive subtype was predictive for disease course in the proband. Distinguishing cognitive subtypes of unaffected siblings may be of relevance for genetic studies.

[Brain activation as endophenotype for investigating genetics of depression]

BACKGROUND

Many factors are involved in the pathogenesis of depression. This article provides an overview of the results given in the thesis entitled 'Linking Depression', in which some putative underlying neurobiological and genetic mechanisms of depression are examined.

AIM

To gain more insight in brain activity as endophenotype for depression.

METHOD

As part of the Netherlands Study of Depression and Anxiety (nesda), 301 people, including patients with depression and/or anxiety and healthy volunteers, underwent functional magnetic resonance imaging (fmri) and genotyping.

RESULTS

During the processing of negative emotions, patients with depression showed a pattern of heightened limbic activation but less prefrontal activation. The same pattern, but in reverse, was seen during the processing of positive emotions. We showed that the disc1, comt and npy genes were associated with brain activation patterns comparable to those seen in patients with depression. In addition, in cases of depression, there was a different kind of relationship between these genes and brain activation.

CONCLUSION

Depression is characterised by the disturbed processing not only of negative emotions but also of positive emotions. In addition, the studies we describe contribute to our insight into the neurobiology of depression and relevant genetic influences because the results demonstrate that depression alters the relationship between genes and brain activation.

Negative and positive life events are associated with small but lasting change in neuroticism

BACKGROUND

High neuroticism is prospectively associated with psychopathology and physical health. However, within-subject changes in neuroticism due to life experiences (LEs) or state effects of current psychopathology are largely unexplored. In this 2-year follow-up study, four hypotheses were tested: (1) positive LEs (PLEs) decrease and negative LEs (NLEs) increase neuroticism; (2) LE-driven change in neuroticism is partly long-lasting; and (3) partly independent of LE-driven changes in anxiety/depression; and (4) childhood adversity (before age 16 years) moderates the influence of NLEs/PLEs on neuroticism scores in adult life.

METHOD

Data came from the Netherlands Study of Depression and Anxiety [NESDA, n = 2981, mean age 41.99 years (s.d. = 13.08), 66.6% women]. At follow-up (T₂) we assessed PLEs/NLEs with the List of Threatening Experiences (LTE) over the prior 24 months and categorized them over recent and distant PLE/NLE measures (1-3 and 4-24 months prior to T₂ respectively) to distinguish distant NLE/PLE-driven change in trait neuroticism (using the Dutch version of the Neuroticism-Extroversion-Openness Five Factor Inventory, NEO-FFI) from state deviations due to changes in symptoms of depression (self-rated version of the 30-item Inventory of Depressive Symptomatology, IDS-SR30) and anxiety (Beck Anxiety Inventory, BAI).

RESULTS

Distant NLEs were associated with higher and distant PLEs with lower neuroticism scores. The effects of distant LEs were weak but long-lasting, especially for distant PLEs. Distant NLE-driven change in neuroticism was associated with change in symptoms of anxiety/depression whereas the effect of distant PLEs on neuroticism was independent of any such changes. Childhood adversity weakened the impact of distant NLEs but enhanced the impact of distant PLEs on neuroticism.

CONCLUSIONS

Distant PLEs are associated with small but long-lasting decreases in neuroticism regardless of changes in symptom levels of anxiety/depression. Long-lasting increases in neuroticism associated with distant NLEs are mediated by anxiety/depression.