Differences of temporal dynamics and signal complexity of gamma band oscillations in first-episode psychosis during a working memory task

Gamma band oscillations participate in the temporal binding needed to synchronize cortical networks, involved in early sensory and short term memory processes. In earlier studies, alterations of these neurophysiological parameters have been found in psychotic disorders. To date no study has explored the temporal dynamics and signal complexity of gamma band oscillations in first episode psychosis (FEP). To address this issue, gamma band analysis was performed in 15 FEP patients and 18 healthy controls who successfully performed an adapted 2-back working memory task. Multiple linear and logistic regression models were computed to explore the relationship between the cognitive status and gamma oscillation changes over time. Based on regression model results, phase diagrams were constructed and their complexity was estimated using fractal dimension, a mathematical tool that describes shapes as numeric values. When adjusted for gamma values at time lags −3 to −4 ms and −15 to −16 ms, FEP patients displayed significantly higher time-dependent changes than controls, independently of the nature of the task. The present results are consistent with a discoordination of the activity of cortical generators engaged by the stimulus apparition in FEP patients, leading to a global binding deficit. In addition, fractal analysis showing higher complexity of gamma signal, confirmed this deficit. Our results provide evidence for recruitment of supplementary cortical generators as compensating mechanisms and yield further understanding for the pathophysiology cognitive impairments in FEP

Combined Grey Matter VBM and White Matter TBSS Analysis in Young First Episode Psychosis Patients With and Without Cannabis Consumption

Cannabis consumption is temporally associated with the development of first episode psychosis (FEP). Whether or not the chronic use of this substance induces structural brain changes that may be responsible for the cognitive and psychological disturbances in this disorder is still matter of debate. To address this issue, we compared the magnetic resonance imaging (MRI)-assessed grey (GM) and white matter (WM) changes in young FEP patients between users versus non-users of cannabis. This prospective study included 50 consecutive FEP subjects: 33 users (22.7±4.1years, 4 women) and 17 non-users (23.9±4.2years, 10 women). Users were further divided into 15 heavy (23.3±4.5years, 2 women) and 18 light users (22.2±3.8years, 2 women) according to their lifetime cannabis use. Voxel-based-morphometry (VBM) analysis of GM and tract-based-spatial-statistics (TBSS) analysis of WM were performed. Age and gender were used as non-explanatory co-regressors. There were no supra-threshold differences between user and non-user groups for both GM and WM parameters. This was also the case when only heavy users were compared to non-users. Multivariate models controlling for age and gender confirmed these findings. We found no evidence for cannabis consumption related alterations in GM or WM in FEP subjects. Due to the strict correction for multiple comparisons and sample size, we cannot formally exclude subtle morphometric changes associated with cannabis consumption. However, even if present, such potential alterations would be of low magnitud

Sustain and reinforce transition from child to adult mental health care in Switzerland : study protocol

AIM A suboptimal transition in mental health care affects a young person’s wellbeing and health in the long run. We aim to identify a large cohort of young people approaching the transition boundary between child and adolescent and adult mental health services in the canton of Geneva and implement the model of managed transition for a randomly selected subset. METHODS We will perform a nested-cohort randomised controlled trial, which is a modification of the multiple cohort randomised controlled trial, where the allocation to the intervention is conducted by cluster randomisation, with each distinct mental health service constituting a cluster. We will include 387 adolescents with a mental disorder, without intellectual disability and within 18 months of reaching the transition boundary. We will randomly allocate mental health services to the intervention (managed transition) or control group (treatment as usual). The primary outcome is the patient’s health status as measured by Health of the Nation Outcome Scale for Children and Adolescents (HoNOSCA) or Health of the Nation Outcome Scale for adults (HoNOS). CONCLUSIONS This is a protocol of a nested-cohort randomised controlled trial. This study will promote change in health systems management and administration. It will facilitate close collaboration between child and adolescent and adult mental health services, which for decades have been completely separated and differentiated

Mapping child and adolescent mental health services and the interface during transition to adult services in six Swiss cantons

Rationale: Transition in psychiatry refers to the period where young people transit from Child and Adolescent Mental Health Services (CAMHS) to Adult Mental Health Services (AMHS). Discontinuity of care during this period is well-documented but little is known about provisions and transition characteristics and policies across Switzerland. The aim of this article is to describe the architecture of public mental health providers in Switzerland and compare it to EU countries. Method: Two mapping surveys, developed previously for European countries, were adapted and sent to cantonal experts: the adapted European CAMHS Mapping Questionnaire (ECM-Q) assessing the architecture and functioning of CAMHS and the adapted Standardized Assessment Tool for Mental Health Transition (SATMeHT) to map CAMHS-AMHS interface. Results: Data were gathered from six cantons. Activity data and transition policies were comparable between Swiss regions and European countries. The percentage of young people below 19 years who were in care was above 2% in every responding canton with a higher proportion of boys than girls for patients <12 years of age. The transition occurred at the age of 18 years, civil majority, in each canton, and between 0 and 24% (3/7) and 25% and 49% (4/7) of young people were expected to transition. One canton (1/7) benefitted from written guidelines, at the CAMHS level only, regarding transition but none had guidelines for mapping CAMHS/AMHS interface even at the regional level. Conclusion: Despite the availability of resources and even if the possibilities of access to care are on average higher than in many European countries, issues regarding transition remain comparable in six Swiss cantons when compared to Europe. Meaning that beyond resources, it is the coordination between services that needs to be worked on. Importantly, implementing those changes would not require investing financial resources but rather working on the coordination between existing teams

Improving pathways to care for patients at high psychosis risk in Switzerland : PsyYoung study protocol

Aims: Psychotic disorders are one of the main causes of chronic disability in young people. An at-risk mental state (ARMS) is represented by subclinical symptoms that precede the first episode of psychosis (FEP). The PsyYoung project aims to optimize the detection of an ARMS while reducing unnecessary psychiatric treatments. It investigates the effects of service changes on the referrals and outcomes of young people with ARMS or a FEP. Methods: Six psychiatric outpatient clinics in three cantons (Basel-Stadt, Vaud, and Geneva) participated in the project. They passed through an implementation phase including service changes and the adaptation of a standardized stepped care model for diagnosis and assessment, in addition to measures for increasing the awareness, networking and training of local professionals. Preliminary results: All participating cantons had entered the implementation phase. By March 2023, there were 619 referrals to participating sites. A total of 163 patients (37% FEP and 31% ARMS) and 15 close relatives had participated in individual longitudinal assessments, and 26 patients participated in qualitative interviews. Conclusion: This national collaborative project addresses the issue of early intervention for emerging psychoses, and creates spaces for fruitful reflections and collaboration in Switzerland. The ultimate aim of PsyYoung is to harmonize clinical practices in early intervention of psychosis on a national level

Impact of early life stress on the pathogenesis of mental disorders: relation to brain oxidative stress

Stress is an inevitable part of human life and it is experienced even before birth. Stress to some extent could be considered normal and even necessary for the survival and the regular psychological development during childhood or adolescence. However, exposure to prolonged stress could become harmful and strongly impact mental health increasing the risk of developing psychiatric disorders. Recent studies have attempted to clarify how the human central nervous system (CNS) reacts to early life stress, focusing mainly on neurobiological modifications. Oxidative stress, defined as a disequilibrium between the oxidant generation and the antioxidant response, has been recently described as a candidate for most of the observed modifications. In this review, we will discuss how prolonged stressful events during childhood or adolescence (such as early maternal separation, parental divorce, physical violence, sexual or psychological abuses, or exposure to war events) can lead to increased oxidative stress in the CNS and enhance the risk to develop psychiatric diseases such as anxiety, depression, drug abuse or psychosis. Defining the sources of oxidative stress following exposure to early life stress might open new beneficial insights in therapeutic approaches to these mental disorders

Working memory impairments in first-episode psychosis and chronic schizophrenia

Working memory (WM) impairments are core cognitive deficits in patients with schizophrenia linked to prefrontal cortical dysfunctions. Determining the differences between early phases of illness allows a better understanding of its course and constitutes an important guide for treatment. The present cross-sectional study examined differences of working memory functions between 33 first-episode and 29 chronic schizophrenic patients, as well as 64 healthy controls. On the basis of a two-back visual-verbal computerized working memory task, reaction time was slower and accuracy was worse in both patient groups than in controls. Test variables, however, were not significantly different between the patient groups, suggesting stability of the deficits over time. Effect size accuracy variables nevertheless showed larger deficits in chronic patients