Pilot study of the relationship between psychotic manifestations and living environment

The study of subclinical psychotic manifestations (quantitative schizotypy) represents clinical and public health issues. These manifestations are more common than schizophrenia or depression, but rarely identified while it impacts the quality of life. Screening schizotypy in the general population would make it possible to propose prevention strategies. The objectives of the present research is to better understand the determinants and mechanisms of schizotypy in order to identify population..

High degree of mitochondrial gene heterogeneity in the bat tick species Ixodes vespertilionis, I. ariadnae and I. simplex from Eurasia

Background: Phylogeographical studies allow precise genetic comparison of specimens, which were collected over large geographical ranges and belong to the same or closely related animal species. These methods have also been used to compare ticks of veterinary-medical importance. However, relevant data are missing in the case of ixodid ticks of bats, despite (1) the vast geographical range of both Ixodes vespertilionis and Ixodes simplex, and (2) the considerable uncertainty in their taxonomy, which is currently unresolvable by morphological clues. Methods: In the present study 21 ticks were selected from collections or were freshly removed from bats or cave walls in six European and four Asian countries. The DNA was extracted and PCRs were performed to amplify part of the cytochrome oxidase I (COI), 16S and 12S rDNA genes, followed by sequencing for identification and molecular-phylogenetic comparison. Results: No morphological differences were observed between Ixodes vespertilionis specimens from Spain and from other parts of Europe, but corresponding genotypes had only 94.6 % COI sequence identity. An I. vespertilionis specimen collected in Vietnam was different both morphologically and genetically (i.e. with only 84.1 % COI sequence identity in comparison with I. vespertilionis from Europe). Two ticks (collected in Vietnam and in Japan) formed a monophyletic clade and shared morphological features with I. ariadnae, recently described and hitherto only reported in Europe. In addition, two Asiatic specimens of I. simplex were shown to differ markedly from European genotypes of the same species. Phylogenetic relationships of ticks showed similar clustering patterns with those of their associated bat host species. Conclusions: Although all three ixodid bat tick species evaluated in the present study appear to be widespread in Eurasia, they exhibit pronounced genetic differences. Data of this study also reflect that I. vespertilionis may represent a species complex

Schizophrenia Bulletin Open

Treatment-resistant schizophrenia (TRS) affects around 30% of patients with schizophrenia (SZ) resulting in poor functioning, relapses, and reduced quality of life. Convergent findings show that inflammation could contribute to resistance. We thus search for immune signatures of patients with TRS/ultra TRS (UTRS) in a sample of community-dwelling outpatients with SZ. In total, 195 stabilized SZ patients (mean age = 31.2 years, 73% male gender) were consecutively included in the network of the FondaMental Expert Centers for Schizophrenia in France and received a thorough clinical assessment. At inclusion, psychotic symptomatology was evaluated by the Positive and Negative Syndrome Scale (PANSS) for schizophrenia. Circulating serum/plasma levels of a large panel of markers reflecting the main inflammatory pathways were evaluated. TRS was defined by current treatment by clozapine (CLZ) and UTRS by current CLZ treatment + PANSS total score ≥ 70. The frequency of TRS and UTRS patients was, respectively, 20% and 7.7% and was defined using multivariable analysis elevated by high levels of interleukin (IL)-12/IL-23p40, IL-17A, IL-10, and beta 2 microglobulin (B2M) and IL-12/IL-23p40, IL-17A, IL-6, IL-10, IFNγ, and B2M, respectively. These observations suggest that resistance and ultra resistance to CLZ treatment are underpinned by pro-inflammatory molecules mainly belonging to the T helper 17 pathway, a finding making sense given the interplay between inflammation and antipsychotic treatment responses. If confirmed, our findings may allow us to consider IL-23/IL-17 pathway as a therapeutic target for patients with resistance to antipsychotics.Sorbonne Universités à Paris pour l'Enseignement et la RechercheFondaMental-Cohorte

First-episode psychosis patients who deteriorated in the premorbid period do not have higher polygenic risk scores than others: A cluster analysis of EU-GEI data

Cluster studies identified a subgroup of patients with psychosis whose premorbid adjustment deteriorates before the onset, which may reflect variation in genetic influence. However, other studies reported a complex relationship between distinctive patterns of cannabis use and cognitive and premorbid impairment that is worthy of consideration. We examined whether: (1) premorbid social functioning (PSF) and premorbid academic functioning (PAF) in childhood and adolescence and current intellectual quotient (IQ) define different clusters in 802 first-episode of psychosis (FEP) patients; resulting clusters vary in (2) polygenic risk scores (PRSs) for schizophrenia (SCZ_PRS), bipolar disorder (BD_PRS), major depression (MD_PRS), and IQ (IQ_PRS), and (3) patterns of cannabis use, compared to 1,263 population-based controls. Four transdiagnostic clusters emerged (BIC = 2268.5): (1) high-cognitive-functioning (n = 205), with the highest IQ (Mean = 106.1, 95% CI: 104.3, 107.9) and PAF, but low PSF. (2) Low-cognitive-functioning (n = 223), with the lowest IQ (Mean = 73.9, 95% CI: 72.2, 75.7) and PAF, but normal PSF. (3) Intermediate (n = 224) (Mean_IQ = 80.8, 95% CI: 79.1, 82.5) with low-improving PAF and PSF. 4) Deteriorating (n = 150) (Mean_IQ = 80.6, 95% CI: 78.5, 82.7), with normal-deteriorating PAF and PSF. The PRSs explained 7.9% of between-group membership. FEP had higher SCZ_PRS than controls [F(4,1319) = 20.4, P < .001]. Among the clusters, the deteriorating group had lower SCZ_PRS and was likelier to have used high-potency cannabis daily. Patients with FEP clustered according to their premorbid and cognitive abilities. Pronounced premorbid deterioration was not typical of most FEP, including those more strongly predisposed to schizophrenia, but appeared in a cluster with a history of high-potency cannabis use

Contributions à l'étude des fonctions éxecutives dans la schizophrénie

PARIS5-BU Saints-Pères (751062109) / SudocBOULOGNE-BU Psych. Henri Pieron (920125201) / SudocSudocFranceF

Schizophrenia: Developmental Variability Interacts with Risk Factors to Cause the Disorder: Nonspecific Variability-Enhancing Factors Combine with Specific Risk Factors to Cause Schizophrenia

International audienceA new etiological model is proposed for schizophrenia that combines variability-enhancing nonspecific factors acting during development with more specific risk factors. This model is better suited than the current etiological models of schizophrenia, based on the risk factors paradigm, for predicting and/or explaining several important findings about schizophrenia: high co-morbidity rates, low specificity of many risk factors, and persistence in the population of the associated genetic polymorphisms. Compared with similar models, e.g., de-canalization, common psychopathology factor, sexual-selection, or differential sensitivity to the environment, this proposal is more general and integrative. Recently developed research methods have proven the existence of genetic and environmental factors that enhance developmental variability. Applying such methods to newly collected or already available data can allow for testing the hypotheses upon which this model is built. If validated, this model may change the understanding of the etiology of schizophrenia, the research models, and preventionbrk paradigms

Étude pilote des relations entre manifestations psychotiques et environnement de résidence

International audienceCet article aborde les déterminants des troubles psychotiques à travers l’étude des manifestations psychotiques « atténuées » (ou schizotypie quantitative) ; manifestations plus fréquentes que les troubles constitués (telle que la schizophrénie) mais rarement identifiés et pris en charge alors qu’ils impactent la qualité de vie. Si les déterminants individuels de ces troubles « atténués » sont plutôt bien connus, l’impact des déterminants contextuels (caractéristiques sociales, urbanistiques) des lieux de vie sur leur présence ou leur intensité n’a, par contre, pas encore été étudié. Les relations entre contexte de résidence et schizophrénie ont, en revanche, fait l’objet de recherches spécifiques.A partir de données recueillies auprès de 255 adultes résidant dans trois quartiers de la commune de Créteil, cette étude s’intéresse aux relations entre les représentations (dont l’étendue) du quartier de résidence, les caractéristiques (socio-démographiques et urbanistiques) du quartier etles scores de schizotypie

Psychotic Experiences Are Associated With Paternal Age But Not With Delayed Fatherhood in a Large, Multinational, Community Sample

Advanced paternal age has been consistently associated with an increased risk of schizophrenia. It is less known if such an association also exists with subclinical/attenuated forms of psychosis. Additionally, it has been suggested that it is not paternal age per se, but rather delayed fatherhood, as a marker of a genetic liability of psychosis, that is the cause of the association. The aim of the current study was to examine whether paternal age and/or delayed fatherhood (paternity age) predict self-reported positive, negative, and/or depressive dimensions of psychosis in a large sample from the general population. The sample (N = 1465) was composed of control subjects from the 6 countries participating in the European Union Gene-Environment Interaction study. The CAPE, a self-report questionnaire, was used to measure dimensions of subclinical psychosis. Paternal age at the time of respondents' birth and age of paternity were assessed by self-report. We assessed the influence of the variables of interest (paternal age or paternity age) on CAPE scores after adjusting for potential confounders (age, gender, and ethnicity). Paternal age was positively associated with the positive dimension of the CAPE. By contrast, paternity age was not associated with any of the psychosis dimensions assessed by the CAPE. Thus, our results do not support the idea that delayed fatherhood explains the association between age of paternity and psychosis risk. Furthermore, our results provide arguments for the hypothesis of an etiologic continuum of psychosis

A latent class analysis of psychotic symptoms in the general population

International audienceIndividuals with psychotic symptoms may actually correspond to various subgroups, characterized by different patterns of psychotic symptoms as well as specific sociodemographic and clinical correlates. We aimed to identify groups of individuals from the general population with specific patterns of psychotic symptoms.In a 38,694-subject survey, a latent class analysis was performed to identify subgroups based on the distribution of seven psychotic symptoms taken from the Mini International Neuropsychiatric Interview. The different classes were subsequently compared according to sociodemographic and clinical correlates.The best fit was obtained with a four-class solution, including the following: (1) a class with a low prevalence of all psychotic symptoms ('LOW', 85.9%); (2) a class with a high prevalence of all psychotic symptoms ('HAL + DEL', 1.7%); and classes with a high prevalence of (3) hallucinations ('HAL', 4.5%) or (4) delusions ('DEL', 7.9%). The HAL + DEL class displayed higher rates of history of trauma, social deprivation and migrant status, while the HAL and DEL classes displayed intermediate rates between HAL + DEL and LOW. HAL + DEL displayed the highest rates of psychotic and non-psychotic disorders and the use of mental health treatment, while HAL and DEL displayed intermediate rates of these disorders between HAL + DEL and LOW. In comparison to the HAL class, psychotic and substance use disorders were more frequent in the DEL class, while anxiety and mood disorders were less frequent.These findings support the hypothesis of a continuum model relating the level of psychotic symptoms to the level of global psychopathology