Consensus paper of the WFSBP task force on cannabis, cannabinoids and psychosis.

Objectives: The liberalisation of cannabis laws, the increasing availability and potency of cannabis has renewed concern about the risk of psychosis with cannabis.

Methods: The objective of the WFSBP task force was to review the literature about this relationship.

Results: Converging lines of evidence suggest that exposure to cannabis increases the risk for psychoses ranging from transient psychotic states to chronic recurrent psychosis.

Connectomic correlates of response to treatment in first-episode psychosis.

Connectomic approaches using diffusion tensor imaging have contributed to our understanding of brain changes in psychosis, and could provide further insights into the neural mechanisms underlying response to antipsychotic treatment. We here studied the brain network organization in patients at their first episode of psychosis, evaluating whether connectome-based descriptions of brain networks predict response to treatment, and whether they change after treatment. Seventy-six patients with a first episode of psychosis and 74 healthy controls were included.

Globally Efficient Brain Organization and Treatment Response in Psychosis: A Connectomic Study of Gyrification.

Background: Converging evidence suggests that patients with first-episode psychosis who show a poor treatment response may have a higher degree of neurodevelopmental abnormalities than good Responders. Characterizing the disturbances in the relationship among brain regions (covariance) can provide more information on neurodevelopmental integrity than searching for localized changes in the brain. Graph-based connectomic approach can measure structural covariance thus providing information on the maturational processes.

Rare loss-of-function variants in SETD1A are associated with schizophrenia and developmental disorders.

By analyzing the whole-exome sequences of 4,264 schizophrenia cases, 9,343 controls and 1,077 trios, we identified a genome-wide significant association between rare loss-of-function (LoF) variants in SETD1A and risk for schizophrenia (P = 3.3 × 10(-9)). We found only two heterozygous LoF variants in 45,376 exomes from individuals without a neuropsychiatric diagnosis, indicating that SETD1A is substantially depleted of LoF variants in the general population.

White matter integrity as a predictor of response to treatment in first episode psychosis.

The integrity of brain white matter connections is central to a patient's ability to respond to pharmacological interventions. This study tested this hypothesis using a specific measure of white matter integrity, and examining its relationship to treatment response using a prospective design in patients within their first episode of psychosis. Diffusion tensor imaging data were acquired in 63 patients with first episode psychosis and 52 healthy control subjects (baseline).

Cortical folding defects as markers of poor treatment response in first-episode psychosis.

Importance: At present, no reliable predictors exist to distinguish future responders from nonresponders to treatment during the first episode of psychosis. Among potential neuroimaging predictors of treatment response, gyrification represents an important marker of the integrity of normal cortical development that may characterize, already at illness onset, a subgroup of patients with particularly poor outcome.

Objective: To determine whether patients with first-episode psychosis who do not respond to 12 weeks of antipsychotic treatment already have significant gyrification defects at illness onset.

Neuropsychological, clinical and cognitive insight predictors of outcome in a first episode psychosis study.

The outcome of first episode psychosis (FEP) is highly variable and difficult to predict. We studied prospectively the impact of poor insight and neuropsychological deficits on outcomes in a longitudinal cohort of 127 FEP patients. Participants were assessed on 5 domains of cognitive function and 2 domains of insight (clinical and cognitive).

Sexual dysfunction in people with prodromal or first-episode psychosis.

Background: Sexual dysfunction is common in psychotic disorder but it is not clear whether it is intrinsic to the development of the illness or secondary to other factors.

Aims: To compare sexual function in people at ultra-high risk (UHR) of a psychotic disorder, patients with first-episode psychosis predominantly taking antipsychotic drugs and healthy volunteers.

Method: Sexual function was assessed in a UHR group (n = 31), a group with first-episode psychosis (n = 37) and a matched control group of healthy volunteers (n = 56) using the Sexual Function Questionnaire.

Pre-morbid Conduct Disorder symptoms are associated with cannabis use among individuals with a first episode of psychosis.

Background: Early cannabis use has consistently been associated with an increased risk for the later development of psychosis. Studies suggest that Conduct Disorder (CD) is more common amongst young people who later go on to develop psychosis. CD has been associated with greater and earlier cannabis use in general population samples.

Opposite effects of catechol-O-methyltransferase Val158Met on cortical function in healthy subjects and patients with schizophrenia.

Background: Catechol-O-methyltransferase (COMT) is essential for dopamine metabolism in the brain, and normal variation in the COMT Val158Met polymorphism can influence regional brain function during cognitive tasks. How this is affected when central dopamine function is perturbed is unclear. We addressed this by comparing the effects of COMT Val158Met genotype on cortical activation during a task of executive functions in healthy and schizophrenic subjects.

Association study of dysbindin gene with clinical and outcome measures in a representative cohort of Italian schizophrenic patients.

There is evidence suggesting that Dysbindin (DTNBP1) is a susceptibility gene for schizophrenia in Caucasian, Chinese, and Japanese populations. We sought to determine if dysbindin was associated with schizophrenia and its symptoms in a representative group of schizophrenic patients from a Community-Based Mental Health Service (CMHS) in Verona, Italy. A prevalence cohort of schizophrenic patients (n = 141) was assessed at baseline and then 3 and 6 years later.