Soc Psychiatry Psychiatr Epidemiol
November 2024
Purpose: The Clinical High Risk (CHR) concept has a limited transition risk to psychotic disorders (PD). This study investigates the association between affective and negative symptoms, currently not included in the CHR concept, and the risk of transition to PD in a community-based population of 2185 participants in Turkey.
Methods: Participants were assessed twice over six years using a multistage sampling technique.
Background: The relationship between childhood trauma (CT) and psychotic symptoms in patients with schizophrenia (SCZ), and subthreshold psychotic experiences in non-clinical populations is well-established. However, little is known about the relationship between subtypes of trauma and specific symptoms in patients, their siblings, and controls. It is also not clear which variables mediate the relationship between trauma and psychotic symptoms.
View Article and Find Full Text PDFBackground: The incidence of psychotic disorders varies in different geographic areas. As there has been no report from Turkey, this study aimed to provide the treated incidence rate of first-episode psychosis (FEP) in a defined area.
Methods: All individuals, aged 15-64 years, presenting with FEP (ICD-10 F20-29, F30-33) to mental health services in a defined catchment-area in Sinop which is located in the Black Sea region of the northern Turkey were recorded over a 4-year period (2009 to 2012).
Purpose: This paper aims to investigate associations between early childhood and current indicators of socioeconomic inequality and the onset (incident), persistence and progression (increase in severity) of psychotic experiences (PEs) in a longitudinal follow-up of a community-based population.
Methods: Households in the metropolitan area of Izmir, Turkey were contacted in a multistage clustered probability sampling frame, at baseline (T, n = 4011) and at 6-year follow-up (T, n = 2185). Both at baseline and follow-up, PEs were assessed using Composite International Diagnostic Interview 2.
Schizophrenia is frequently accompanied with social cognitive disturbances. Cannabis represents one established environmental factor associated with the onset and progression of schizophrenia. The present cross-sectional study aimed to investigate the association of facial emotion recognition (FER) performance with cannabis use in 2039 patients with schizophrenia, 2141 siblings, and 2049 healthy controls (HC).
View Article and Find Full Text PDFBackground: Social capital is thought to represent an environmental factor associated with the risk of psychotic disorder (PD). This study aims to investigate the association between neighbourhood-level social capital and clinical transitions within the spectrum of psychosis.
Methods: In total, 2175 participants, representative of a community-based population, were assessed twice (6 years apart) to determine their position within an extended psychosis spectrum: no symptoms, subclinical psychotic experiences (PE), clinical PE, PD.
Objective: The aim of this study is to evaluate the associations between alcohol-cannabis use and forensic/stressful events with the risk of incident clinical psychosis during follow-up.
Method: A community-based sample (n: 2142) was screened for clinical psychosis (schizophrenia and other psychotic disorders, affective disorders with psychotic features) at baseline and follow-up. Thus, incident clinical psychosis cases to develop during follow-up (individuals with no clinical psychosis at the baseline assessment and with clinical psychosis at the follow-up assessment) were detected (n: 27).
Noro Psikiyatr Ars
September 2021
Introduction: In this review, a historical and conceptual panorama of symptomatic remission will be provided with a focus on the whole clinical psychosis beyond schizophrenia.
Methods: We included all published articles on remission in psychosis, without any restrictions regarding language or year. We used a string to detect relevant articles in PubMed.
Prog Neuropsychopharmacol Biol Psychiatry
March 2022
Background: Social cognition impairments, such as facial emotion recognition (FER), have been acknowledged since the earliest description of schizophrenia. Here, we tested FER as an intermediate phenotype for psychosis using two approaches that are indicators of genetic risk for schizophrenia: the proxy-genetic risk approach (family design) and the polygenic risk score for schizophrenia (PRS-SCZ).
Methods: The sample comprised 2039 individuals with schizophrenia, 2141 siblings, and 2049 healthy controls (HC).
Background: A cumulative environmental exposure score for schizophrenia (exposome score for schizophrenia [ES-SCZ]) may provide potential utility for risk stratification and outcome prediction. Here, we investigated whether ES-SCZ was associated with functioning in patients with schizophrenia spectrum disorder, unaffected siblings, and healthy controls.
Methods: This cross-sectional sample consisted of 1,261 patients, 1,282 unaffected siblings, and 1,525 healthy controls.
Important questions remain about the profile of cognitive impairment in psychotic disorders across adulthood and illness stages. The age-associated profile of familial impairments also remains unclear, as well as the effect of factors, such as symptoms, functioning, and medication. Using cross-sectional data from the EU-GEI and GROUP studies, comprising 8455 participants aged 18 to 65, we examined cognitive functioning across adulthood in patients with psychotic disorders (n = 2883), and their unaffected siblings (n = 2271), compared to controls (n = 3301).
View Article and Find Full Text PDFBackground: There is evidence that environmental and genetic risk factors for schizophrenia spectrum disorders are transdiagnostic and mediated in part through a generic pathway of affective dysregulation.
Methods: We analysed to what degree the impact of schizophrenia polygenic risk (PRS-SZ) and childhood adversity (CA) on psychosis outcomes was contingent on co-presence of affective dysregulation, defined as significant depressive symptoms, in (i) NEMESIS-2 ( = 6646), a representative general population sample, interviewed four times over nine years and (ii) EUGEI ( = 4068) a sample of patients with schizophrenia spectrum disorder, the siblings of these patients and controls.
Results: The impact of PRS-SZ on psychosis showed significant dependence on co-presence of affective dysregulation in NEMESIS-2 [relative excess risk due to interaction (RERI): 1.
Background: This study attempted to replicate whether a bias in probabilistic reasoning, or 'jumping to conclusions'(JTC) bias is associated with being a sibling of a patient with schizophrenia spectrum disorder; and if so, whether this association is contingent on subthreshold delusional ideation.
Methods: Data were derived from the EUGEI project, a 25-centre, 15-country effort to study psychosis spectrum disorder. The current analyses included 1261 patients with schizophrenia spectrum disorder, 1282 siblings of patients and 1525 healthy comparison subjects, recruited in Spain (five centres), Turkey (three centres) and Serbia (one centre).
Introducton: The impact of social environment on the frequency and prevalence of schizophrenia is well known. However, in schizophrenia and other psychotic disorders, there are few studies which investigate the effect of social environment on disease prognosis and relapse. The aim of this study was to investigate the effect of neighborhood social capital level and address change on relapse in schizophrenia and similar psychotic disorders.
View Article and Find Full Text PDFWhite noise speech illusions index liability for psychotic disorder in case-control comparisons. In the current study, we examined i) the rate of white noise speech illusions in siblings of patients with psychotic disorder and ii) to what degree this rate would be contingent on exposure to known environmental risk factors (childhood adversity and recent life events) and level of known endophenotypic dimensions of psychotic disorder [psychotic experiences assessed with the Community Assessment of Psychic Experiences (CAPE) scale and cognitive ability]. The white noise task was used as an experimental paradigm to elicit and measure speech illusions in 1,014 patients with psychotic disorders, 1,157 siblings, and 1,507 healthy participants.
View Article and Find Full Text PDFExposures constitute a dense network of the environment: exposome. Here, we argue for embracing the exposome paradigm to investigate the sum of nongenetic "risk" and show how predictive modeling approaches can be used to construct an exposome score (ES; an aggregated score of exposures) for schizophrenia. The training dataset consisted of patients with schizophrenia and controls, whereas the independent validation dataset consisted of patients, their unaffected siblings, and controls.
View Article and Find Full Text PDFTürkSch is a prospective, longitudinal study in a representative community sample (İzmir, Turkey), consisting of several data collection stages, to screen and follow-up mental health outcomes, with a special focus on the extended and transdiagnostic psychosis phenotype. The aim of the present paper is to describe the research methodology, data collection results, and associations with noncontact and refusal in the longitudinal arm. Households were contacted in a multistage clustered probability sampling frame, covering 11 districts and 302 neighborhoods at baseline (n = 4,011) and at 6-year follow-up (n = 2,185).
View Article and Find Full Text PDFBackground: First-degree relatives of patients with psychotic disorder have higher levels of polygenic risk (PRS) for schizophrenia and higher levels of intermediate phenotypes.
Methods: We conducted, using two different samples for discovery (n = 336 controls and 649 siblings of patients with psychotic disorder) and replication (n = 1208 controls and 1106 siblings), an analysis of association between PRS on the one hand and psychopathological and cognitive intermediate phenotypes of schizophrenia on the other in a sample at average genetic risk (healthy controls) and a sample at higher than average risk (healthy siblings of patients). Two subthreshold psychosis phenotypes, as well as a standardised measure of cognitive ability, based on a short version of the WAIS-III short form, were used.
Schizophrenia is a heritable complex phenotype associated with a background risk involving multiple common genetic variants of small effect and a multitude of environmental exposures. Early twin and family studies using proxy-genetic liability measures suggest gene-environment interaction in the etiology of schizophrenia spectrum disorders, but the molecular evidence is scarce. Here, by analyzing the main and joint associations of polygenic risk score for schizophrenia (PRS-SCZ) and environmental exposures in 1,699 patients with a diagnosis of schizophrenia spectrum disorders and 1,542 unrelated controls with no lifetime history of a diagnosis of those disorders, we provide further evidence for gene-environment interaction in schizophrenia.
View Article and Find Full Text PDFSoc Psychiatry Psychiatr Epidemiol
March 2019
Background: Psychotic experiences (PEs) are not exclusive to psychotic disorders and highly correlated with mood episodes. In this representative general population-based study, longitudinal bidirectional associations between the extended psychosis phenotype and mood episodes were investigated, accounting for other possible causes.
Methods: Households were contacted in a multistage clustered probability sampling frame covering 11 districts and 302 neighbourhoods at baseline (n = 4011) and at 6-year follow-up (n = 2185).
Background: Psychotic experiences (PEs) may predict a range of common, non-psychotic disorders as well as psychotic disorders. In this representative, general population-based cohort study, both psychotic and non-psychotic disorder outcomes of PE were analysed, as were potential moderators.
Methods: Addresses were contacted in a multistage clustered probability sampling frame covering 11 districts and 302 neighbourhoods at baseline (n = 4011).
There is little research on genetic risk for the extended psychosis phenotype ranging from psychotic experiences (PEs) to psychotic disorders (PDs). In this general population-based prospective cohort study, the longitudinal associations between BDNF-Val66Met polymorphism and the different levels of the extended psychosis phenotype were investigated. Addresses were contacted in a multistage clustered probability sampling frame covering 11 districts and 302 neighborhoods at baseline (n = 4011).
View Article and Find Full Text PDFObjective: Psychotic disorders were previously associated with catechol- O-methyltransferase (COMT) val158met (rs4680) and brain-derived neurotrophic factor (BDNF) val66met (rs6265) polymorphisms. This article evaluates the association between COMT/BDNF polymorphisms and the extended psychosis phenotype which covers not only schizophrenia but also subclinical expressions of psychotic experiences.
Method: The participants of this study were part of the TürkSch (Izmir Mental Health Survey for Gene-Environment Interaction in Psychoses), a longitudinal study Psychotic experiences and disorders were screened 437.
To determine the prevalence of and factors influencing premenstrual syndrome (PMS) in first-year students at a university health campus and to evaluate the relationship between depression and PMS. Methods: This cross-sectional study was conducted on a population of 618 university students from March to June 2016 at Dokuz Eylül University, Izmir, Turkey. Data were collected using the Premenstrual Syndrome Scale (PMSS), Beck Depression Inventory and Student Identification Form.
View Article and Find Full Text PDF