Psychotic-like experiences in major depression and anxiety disorders: a population-based survey in young adults

Psychotic-like experiences and problem drinking among adults in Japan

BACKGROUND

Psychotic-like experiences (PLEs) are common in the general population and have been linked to alcohol misuse and abuse. However, much of this research has been undertaken in Western countries. To address this deficit, the current study examined the association between PLEs and problem drinking in the Japanese general population.

METHODS

Data were used from 3717 adults (age 18-89) collected in an online survey in 2023. Information was obtained on PLEs with the PRIME Screen-Revised (PS-R), while problem drinking was assessed with the CAGE questionnaire (where a score of ≥ 2 was used to categorize cases). Logistic regression was used to examine the associations.

RESULTS

Problem drinking was prevalent in the study sample (12.5%). In an analysis that was adjusted for sociodemographic factors, self-rated health, smoking status and depressive symptoms, PLEs were associated with significantly higher odds for problem drinking in the total sample (OR: 1.70, 95%CI: 1.13-2.55). In a sex-stratified analysis PLEs were not linked to problem drinking in men (OR: 1.16, 95%CI 0.68-2.00), whereas women with PLEs had over 2.8 times higher odds for problem drinking (OR: 2.83, 95%CI: 1.54-5.21).

CONCLUSION

PLEs are associated with problem drinking in the Japanese general population and this association is especially pronounced in women. As problem drinking has been linked to a number of detrimental outcomes, future research should examine the potential effects of problem drinking in individuals with PLEs.

Impaired Sleep Mediates the Relationship Between Interpersonal Trauma and Subtypes of Delusional Ideation

BACKGROUND AND HYPOTHESIS

Trauma is a robust risk factor for delusional ideation. However, the specificity and processes underlying this relationship are unclear. Qualitatively, interpersonal traumas (i.e., trauma caused by another person) appear to have a specific relationship with delusional ideation, particularly paranoia, given the commonality of social threat. However, this has not been empirically tested and the processes by which interpersonal trauma contributes to delusional ideation remain poorly understood. Given the role of impaired sleep in both trauma and delusional ideation, it may be a critical mediator between these variables. We hypothesized that interpersonal trauma, but not non-interpersonal trauma, would be positively related to subtypes of delusional ideation, especially paranoia, and that impaired sleep would mediate these relationships.

STUDY DESIGN

In a large, transdiagnostic community sample (N = 478), an exploratory factor analysis of the Peter's Delusion Inventory identified three subtypes of delusional ideation, namely magical thinking, grandiosity, and paranoia. Three path models, one for each subtype of delusional ideation, tested whether interpersonal trauma and non-interpersonal trauma were related to subtypes of delusional ideation, and impaired sleep as a mediating variable of interpersonal trauma.

STUDY RESULTS

Paranoia and grandiosity were positively related to interpersonal trauma and unrelated to non-interpersonal trauma. Furthermore, these relationships were significantly mediated by impaired sleep, which appeared strongest for paranoia. In contrast, magical thinking was unrelated to traumatic experiences.

CONCLUSIONS

These findings support a specific relationship between interpersonal trauma and paranoia as well as grandiosity, with impaired sleep appearing as an important process by which interpersonal trauma contributes to both.

Serial multiple mediating roles of anxiety and thyroid-stimulating hormone in the relationship between depression and psychotic symptoms in young adults with anxious depression

BACKGROUND

Psychotic symptoms (PS) frequently occur in young adults with anxious depression (AD), yet the mediators of the associations between depression and PS remain unclear. This study aimed to investigate the prevalence and risk factors of PS in first-episode and drug-naïve (FEDN) young adults with AD and attempted to elucidate the relationship between thyroid-stimulating hormone (TSH) levels, anxiety, depression, and PS, as well as to identify potential mediating roles.

METHODS

369 FEDN young adults with AD were recruited. Clinical symptoms were assessed using the Positive and Negative Syndrome Scale's positive subscale, the Hamilton Depression Rating Scale (HAMD), and the Hamilton Anxiety Rating Scale (HAMA). Fasting glucose, lipids, and thyroid function were also collected.

RESULTS

The prevalence of PS in young adults with AD (21.68 %) was 12.24 times higher than in non-AD patients. The HAMD scores (P = 0.005, OR = 1.23), HAMA scores (P < 0.001, OR = 1.62), and TSH levels (P = 0.025, OR = 1.20) were significant predictors of PS. The combined area under the curve value for distinguishing young adults with AD with and without PS was 0.86. We also identified serial multiple mediating effects of TSH levels and anxiety on the association of depression with PS.

CONCLUSIONS

These findings emphasize the role of anxiety and TSH levels as serial mediators of the association between depression and PS. Therefore, when treating PS in young adults with AD, it is important to focus not only on depression, but also on TSH levels and anxiety to maximize benefit.

Anxious distress in people with major depressive episodes: a cross-sectional analysis of clinical correlates

OBJECTIVE

Most people with major depressive episodes meet the criteria for the anxious distress (AD) specifier defined by DSM-5 as the presence of symptoms such as feelings of tension, restlessness, difficulty concentrating, and fear that something awful may happen. This cross-sectional study was aimed at identifying clinical correlates of AD in people with unipolar or bipolar depression.

METHODS

Inpatients with a current major depressive episode were included. Data on socio-demographic and clinical variables were collected. The SCID-5 was used to diagnose depressive episodes and relevant specifiers. The Montgomery-Åsberg Depression Rating Scale (MADRS) and Young Mania Rating Scale (YMRS) were used to assess the severity of depressive and manic (mixed) symptoms, respectively. Multiple logistic regression analyses were carried out to identify clinical correlates of AD.

RESULTS

We included 206 people (mean age: 48.4 ± 18.6 yrs.; males: 38.8%) admitted for a major depressive episode (155 with major depressive disorder and 51 with bipolar disorder). Around two-thirds of the sample (N = 137; 66.5%) had AD. Multiple logistic regression models showed that AD was associated with mixed features, higher YMRS scores, psychotic features, and a diagnosis of major depressive disorder (p < 0.05).

CONCLUSION

Despite some limitations, including the cross-sectional design and the inpatient setting, our study shows that AD is likely to be associated with mixed and psychotic features, as well as with unipolar depression. The identification of these clinical domains may help clinicians to better contextualize AD in the context of major depressive episodes.

Clinical presentation of psychotic experiences in patients with common mental disorders attending the UK primary care improving access to psychological therapies (IAPT) Programme

BACKGROUND

Improving Access to Psychological Therapies (IAPT) services address anxiety and depression in primary care, with psychotic disorders typically excluded. Our previous research found 1 in 4 patients report distressing psychotic experiences (PE) alongside common mental disorders, yet little is known about their clinical presentation and impact on recovery.

METHODS

We used the Community Assessment of Psychic Experiences - Positive Scale (CAPE-P15) to assess the clinical presentation and symptomatic profile of PE within IAPT settings across three National Health Service (NHS) trusts, serving a diverse population in Southern England. We identified different classes based on the reported PE frequencies using latent class analysis.

RESULTS

A total of 2042 IAPT patients completed the CAPE-P15. The mean age was 39.8 (±15.3) years. We identified five distinct classes of symptom profiles, findings that PE were common, especially self-referential and persecutory ideas. Prevalence and intensity increased across classes, extending to bizarre experiences and perceptual abnormalities in the fifth and least common class. Perceptual abnormalities were a strong indicator of symptom severity, with patients being the least likely to achieve recovery by the end of treatment.

LIMITATIONS

Data were collected during a service evaluation. Replication of these findings across other IAPT services could prove beneficial. We did not collect information on negative PE.

CONCLUSIONS

Patients seeking treatment for anxiety and depression in primary care commonly experience a wide range of positive PE. Self-referential and persecutory ideation were prevalent; perceptual abnormalities were infrequent. Providing information about prevalence and tailoring therapy may help reduce patient distress.

Childhood Adversity and Emerging Psychotic Experiences: A Network Perspective

BACKGROUND AND HYPOTHESIS

Childhood adversity is associated with a myriad of psychiatric symptoms, including psychotic experiences (PEs), and with multiple psychological processes that may all mediate these associations.

STUDY DESIGN

Using a network approach, the present study examined the complex interactions between childhood adversity, PEs, other psychiatric symptoms, and multiple psychological mediators (ie, activity-related and social stress, negative affect, loneliness, threat anticipation, maladaptive cognitive emotion regulation, attachment insecurity) in a general population, adolescent sample (n = 865, age 12-20, 67% female).

STUDY RESULTS

Centrality analyses revealed a pivotal role of depression, anxiety, negative affect, and loneliness within the network and a bridging role of threat anticipation between childhood adversity and maladaptive cognitive emotion regulation. By constructing shortest path networks, we found multiple existing paths between different categories of childhood adversity and PEs, with symptoms of general psychopathology (ie, anxiety, hostility, and somatization) as the main connective component. Sensitivity analyses confirmed the robustness and stability of the networks. Longitudinal analysis in a subsample with Wave 2 data (n = 161) further found that variables with higher centrality (ie, depression, negative affect, and loneliness) better predicted follow-up PEs.

CONCLUSIONS

Pathways linking childhood adversity to PEs are complex, with multifaceted psychological and symptom-symptom interactions. They underscore the transdiagnostic, heterotypic nature of mental ill-health in young people experiencing PEs, in agreement with current clinical recommendations.

Prevalence of co-occurring severe depression and psychotic symptoms in college students and its relationship with childhood maltreatment

BACKGROUND

It has been demonstrated that childhood maltreatment (CM) is associated with an increased risk of depression and psychotic symptoms. However, there is still a lack of studies on the prevalence of co-occurring severe depression and psychotic symptoms (CSDPS) and the association between CM and CSDPS among college students.

OBJECTIVE

We aim to investigate the prevalence and demographic distribution of CSDPS among Chinese college students and to examine its relationship with CM.

PARTICIPANTS AND SETTING

A total of 7351 college students aged 18 and above completed the survey. Finally, 6854 valid questionnaires were included for further analysis.

METHODS

The Childhood Trauma Questionnaire and the item for witnessing domestic violence were used to assess the CM. The Prodromal Questionnaire-16 and the depression subscale of the Depression Anxiety and Stress-21 scale were used to assess psychotic symptoms and depressive symptoms.

RESULTS

The prevalence of CSDPS was 1.47 % among the college students. The multivariate logistic regression analysis showed that emotional abuse and emotional neglect were associated with an increased risk of CSDPS (all p < 0.05). The risk of CSDPS was dramatically increased for individuals who had experienced ≥3 types of CM (OR = 22.929, p < 0.001), as compared to those who had experienced 1-2 types of CM (OR = 4.452, p < 0.001) and those without the experience of CM.

CONCLUSION

CM was found to be associated with an increased risk of CSDPS among the college students. Notably, experiencing more types of CM was also associated with a higher risk of CSDPS.

Psychosis screening questionnaire: Exploring its factor structure among South African adults

Background

Early detection of psychosis improves treatment outcomes, but there is limited research evaluating the validity of psychosis screening instruments, particularly in low-resourced countries.

Aim

This study aims to assess the construct validity and psychometric properties of the psychosis screening questionnaire (PSQ) in South Africa.

Setting

This study was conducted at several health centres in the Western and Eastern Cape provinces in South Africa.

Methods

The sample consisted of 2591 South African adults participating as controls in a multi-country case-control study of psychiatric genetics. Using confirmatory factor analysis and item response theory, we evaluated the psychometric properties of the PSQ.

Results

Approximately 11% of the participants endorsed at least one psychotic experience on the PSQ, and almost half of them (49%) occurred within the last 12 months. A unidimensional model demonstrated good fit (root mean square error of approximation [RMSEA] = 0.023, comparative fit index [CFI] = 0.977 and Tucker-Lewis Index [TLI] = 0.954). The mania item had the weakest association with a single latent factor (standardised factor loading = 0.14). Model fit improved after removing the mania item (RMSEA = 0.025, CFI = 0.991 and TLI = 0.972). With item response theory analysis, the PSQ provided more information at higher latent trait levels.

Conclusion

Consistent with prior literature, the PSQ demonstrated a unidimensional factor structure among South Africans. In our study, the PSQ in screening for psychosis performed better without the mania item, but future criterion validity studies are warranted.

Contribution

This study highlights that PSQ can be used to screen for early psychosis.

Psychosis Symptom Trajectories Across Childhood and Adolescence in Three Longitudinal Studies: An Integrative Data Analysis with Mixture Modeling

Psychotic-like experiences (PLEs) are common throughout childhood, and the presence of these experiences is a significant risk factor for poor mental health later in development. Given the association of PLEs with a broad number of mental health diagnoses, these experiences serve as an important malleable target for early preventive interventions. However, little is known about these experiences across childhood. While these experiences may be common, longitudinal measurement in non-clinical settings is not. Therefore, in order to explore longitudinal trajectories of PLEs in childhood, we harmonized three school-based randomized control trials with longitudinal follow-up to identify heterogeneity in trajectories of these experiences. In an integrative data analysis (IDA) using growth mixture modeling, we identified three latent trajectory classes. One trajectory class was characterized by persistent PLEs, one was characterized by high initial probabilities but improving across the analytic period, and one was characterized by no reports of PLEs. Compared to the class without PLEs, those in the improving class were more likely to be male and have higher levels of aggressive and disruptive behavior at baseline. In addition to the substantive impact this work has on PLE research, we also discuss the methodological innovation as it relates to IDA. This IDA demonstrates the complexity of pooling data across multiple studies to estimate longitudinal mixture models.

Do Anxiety Symptoms Mediate the Association Between Cannabis Use Frequency and Psychotic-Like Experiences in Emerging Adult Undergraduates?

OBJECTIVE

Cannabis is commonly used by Canadian emerging adults (ages 18-25 years), many of whom attend post-secondary institutions. Frequent cannabis use is linked with psychotic-like experiences (PLEs); however, the exact nature of this association remains unclear. Anxiety symptoms may mediate this association, as they are prevalent in emerging adults and have been independently linked with both cannabis use and PLEs. Past work found that anxiety mediated the association between cannabis use frequency and attenuated positive psychotic symptoms (further along the psychosis continuum than PLEs), however this research had yet to be validated in the Canadian population, and trait rather than state anxiety (frequency of anxiety symptoms) was studied. Thus, our primary objective was to examine if anxiety symptoms mediated the association between cannabis use frequency and PLEs in Canadian emerging adult undergraduates. Despite known sex differences in cannabis use, expression of anxiety, and PLEs, past work did not evaluate the potential impact of biological sex on the anxiety-mediated model, and thus is the secondary objective of the present study.

METHODS

1,266 first-/second-year emerging adult undergraduates from five Canadian universities provided cross-sectional, self-report survey data in fall 2021 semester. Validated measures of cannabis use frequency, anxiety, and PLEs were administered.

RESULTS

Path analyses supported mediation from cannabis use to PLEs through anxiety (b  =  0.07, P < 0.001, 95% bootstrap CI [0.03, 0.10]). No direct effect was found (P  =  0.457), suggesting that the cannabis-to-PLEs association was mediated by anxiety. Mediation did not depend on biological sex (i.e., bootstrapped 95% CIs crossed zero).

CONCLUSIONS

Anxiety symptoms mediated the association between cannabis use and PLEs in emerging adults regardless of their biological sex. Assuming replication in prospective research, results highlight anxiety as an important intervention target in frequent cannabis-using emerging adults, to potentially prevent development/worsening of PLEs, and in turn psychotic illness.

Comparing two measures of schizotypy and their relationship with psychological distress in British university students

AIMS

Schizotypy reflects the vulnerability to schizophrenia in the general population. Different questionnaires have been developed to measure aspects of schizotypy. Higher schizotypy scores have also been linked with depression, anxiety, and stress sensitivity. Here we examine the associations of schizotypy with symptoms of depression and anxiety in a sample of university students, using two different measures (N = 271).

METHODS

A series of confirmatory factor analyses was used to examine two distinct and frequently employed measures of schizotypy: the Community Assessment of Psychic Experiences (CAPE), and the Schizotypy Personality Questionnaire (SPQ). We assessed their relationship with each other and their predictive validity for anxiety, depression, and stress sensitivity.

RESULTS

Our results indicated the brief 7-factor SPQ (SPQ-BR) factor solution for the SPQ and the 15-item and 3 factor solution for the CAPE (i.e., CAPE-P15) as best fitting models. Particularly the CAPE dimension of persecutory ideation was a strong predictor of anxiety, depression, and stress sensitivity, whereas the SPQ dimensions of no close friends and social anxiety predicted psychological distress and stress in our student sample.

CONCLUSIONS

Our findings extend earlier work in general and patient samples and point to the importance of understanding the contribution of particularly positive schizotypy symptoms and different interpersonal aspects to psychological distress.

Depression and anxiety mediate the relationship between the retrospectively measured symptoms of premenstrual disorders and negative but not positive psychotic-like experiences

The aim of this study was to examine the relationship between retrospectively measured premenstrual symptoms and subclinical forms of positive and negative psychotic symptoms (psychotic-like experiences; PLEs). It was hypothesised that subjective intensity of the symptoms of premenstrual disorders predicts PLEs frequency and that this relationship is mediated by anxiety and depression. The study sample comprised 108 non-clinical subjects. Study variables were assessed with self-report questionnaires: the Premenstrual Symptoms Screening Tool (PSST); the Beck Depression Inventory Second Edition (BDI-II); the State-Trait Anxiety Inventory (STAI; trait sub-scale); the Community Assessment of Psychic Experiences (CAPE). Regression and mediation analyses were performed. The PSST scores were significantly and positively associated with psychotic-like experiences frequency. The relation was stronger for positive PLEs. Anxiety and depression partially mediated the relationship between premenstrual symptoms and negative PLEs, but not between premenstrual symptoms and positive PLEs. Although the design of the study does not allow to infer causality, it demonstrates strong, positive relationship between the symptoms of premenstrual disorders and psychotic-like experiences. The relationship between premenstrual disorders and negative PLEs seems to be partially based on a general psychopathological factor. Further longitudinal studies are needed to test whether premenstrual disturbances increase risk of psychotic symptoms.

Resting-State Functional Connectivity Explained Psychotic-like Experiences in the General Population and Partially Generalized to Patients and Relatives

Background

Psychotic-like experiences (PLEs) are considered the subclinical portion of the psychosis continuum. Research suggests that there are resting-state functional connectivity (rsFC) substrates of PLEs, yet it is unclear if the same substrates underlie more severe psychosis. Here, to our knowledge, we report the first study to build a cross-validated rsFC model of PLEs in a large community sample and directly test its ability to explain psychosis in an independent sample of patients with psychosis and their relatives.

Methods

Resting-state FC of 855 healthy young adults from the WU-Minn Human Connectome Project (HCP) was used to predict PLEs with elastic net. An rsFC composite score based on the resulting model was correlated with psychotic traits and symptoms in 118 patients with psychosis, 71 nonpsychotic first-degree relatives, and 45 healthy control subjects from the psychosis HCP.

Results

In the HCP, the cross-validated model explained 3.3% of variance in PLEs. Predictive connections spread primarily across the default, frontoparietal, cingulo-opercular, and dorsal attention networks. The model partially generalized to a younger, but not older, subsample in the psychosis HCP, explaining two measures of positive/disorganized psychotic traits (the Structured Interview for Schizotypy: β = 0.25, pone-tailed = .027; the Schizotypy Personality Questionnaire positive factor: β = 0.14, pone-tailed = .041). However, it did not differentiate patients from relatives and control subjects or explain psychotic symptoms in patients.

Conclusions

Some rsFC substrates of PLEs are shared across the psychosis continuum. However, explanatory power was modest, and generalization was partial. It is equally important to understand shared versus distinct rsFC variances across the psychosis continuum.

Evaluation of reliability and validity of the Persian version of Peters et al. delusions inventory (PDI-40) in iranian non-clinical and clinical samples

BACKGROUND

Some individuals may manifest psychotic symptoms that do not fulfill the requisite clinical criteria for a formal diagnosis of psychosis. The assessment of susceptibility to delusions, encompassing both clinical and non-clinical cohorts, frequently makes use of the Peters et al. Delusions Inventory (PDI-40). This study aimed to evaluate the reliability and validity of the Persian version of Peters et al. Delusions Inventory (PDI-40) in Iranian non-clinical and clinical samples.

METHODS

The present study employed a cross-sectional, correlational design in 2020. A total of 1402 Iranian participants were recruited for the study, which consisted of three distinct stages. The first stage involved an Exploratory Factor Analysis (EFA) conducted on a non-clinical sample of 512 participants. The second stage comprising different non-clinical sample 764 participants to perform a Confirmatory Factor Analysis (CFA). In the third stage, a clinical sample of 126 psychotic patients was compared to a non-clinical sample. All participants completed the PDI-40, the Community Assessment of Psychotic Experiences (CAPE-42), and the Depression, Anxiety, and Stress Scale (DASS-21). The internal structure of PDI-40 was examined through the analysis of its factor structure using LISREL 8.8.

RESULTS

The EFA analysis unveiled nine components within Persian version of PDI-40. The CFA analysis demonstrated an excellent fit of the nine-factor structure of Persian PDI-40 to the data. The total score exhibited high internal reliability, as indicated by Cronbach's alpha coefficient of 0.92. Moreover, Persian PDI-40 exhibited satisfactory evidence of convergent validity, as significant correlations were observed between dimensions of PDI-40 and subscales of CAPE-42 and DASS-21. Lastly, findings indicated that psychotic participants scored higher than non-clinical participants in all components of the PDI-40(p < 0.05).

CONCLUSION

Persian version of the PDI-40 demonstrates strong reliability and validity for assessing delusion proneness in both non-clinical and clinical samples in Iran. The observed distinctions between psychotic and non-clinical participants underscore its potential as a valuable tool for discerning delusion proneness in diverse contexts.

Longitudinal relationships of psychotic-like experiences with suicidal ideation and self-harm in adolescents

Research in adolescents suggests associations between psychotic-like experiences (PLEs) and self-injurious thoughts and behaviors (SITBs), but insights into their temporal relationship, which may inform prediction, have been limited. Psychological distress (PD; symptoms of depression and anxiety) has been related to both PLEs and SITBs, and may modulate this relationship. Given that PLEs have been linked to the development of several mental disorders, and the relationships between SITBs and suicide, it is important to better understand their relationship. The present study sought to investigate these factors using a longitudinal school-based design. Adolescents (n = 1685, ages 12-18) completed annual self-report assessments (6 time points) on PLEs, SITBs (suicidal ideation (SI) and self-harm (SH)), as well as PD. The longitudinal associations between PLEs and SITBs were analyzed, employing two cross-lagged panel models (CLPMs), with and without adjustment for PD. Unadjusted CLPMs revealed significant bidirectional temporal associations between PLEs and SITBs (both SI and SH), suggesting that PLEs both predicted and were predicted by SITBs. When adjusting for PD, the effect of SI on PLEs remained significant, but not PLEs on SI; bidirectional associations between PLEs and SH also remained significant. A bidirectional longitudinal relationship where both PLEs and SITBs can precede (and perhaps predict) each other was suggested in adolescents. PD may play a particular role in situations where PLEs are followed by SI. Heightened awareness about relationships between these phenotypes may be an important step toward facilitating timely interventions for both mental disorders and suicide.

Dimensions of psychopathology associated with psychotic-like experiences: Findings from the network analysis in a nonclinical sample

BACKGROUND

Psychotic-like experiences (PLEs) are associated with a variety of psychopathological symptoms. However, it remains unknown which dimensions of psychopathology are most closely related to the occurrence of PLEs. In this study, we aimed to analyze the association of PLEs with various domains of psychopathology.

METHODS

A total of 1100 nonclinical adults (aged 18-35 years, 51.4% females) with a negative history of psychiatric treatment were surveyed. Assessment of psychopathology was performed using self-reports. Symptoms associated with PLEs were explored as continuous variables and based on clinically relevant thresholds using two separate network analyses.

RESULTS

In both network analyses, PLEs were directly connected to obsessive-compulsive disorder (OCD) symptoms, manic symptoms, depressive symptoms, and attention-deficit/hyperactivity disorder (ADHD) symptoms. Anxiety symptoms were associated with PLEs only in the network based on threshold scores. Importantly, edge weight for the connection of PLEs and OCD symptoms was significantly higher compared to edge weights of all other direct connections of PLEs with psychopathology in both networks. Edge weight for the connection between PLEs and manic symptoms was significantly higher compared to edge weights for direct connections of PLEs with depressive and ADHD symptoms in the network based on continuous scores of psychopathological symptoms. Edge weights of direct connections of PLEs with depressive, anxiety, and ADHD symptoms did not differ significantly in both networks.

CONCLUSIONS

Our findings indicate that PLEs are associated with multiple domains of psychopathology. However, these phenomena are most strongly associated with OCD symptoms regardless of their severity threshold.

Psychotic-like experiences in non-clinical subgroups with and without specific beliefs

BACKGROUND

Assuming a transdiagnostic and extended psychosis phenotype, psychotic-like experiences (PLEs) and psychotic symptoms are on a phenomenological and temporal continuum between clinical and non-clinical populations. Recent research points towards differences in PLE proneness in different subgroups and clinical impact of different PLE subtypes. This study examines the prevalence of PLEs in three groups of individuals with and without specific sets of beliefs aiming to elucidate the question whether proneness to PLEs varies according to traditional versus less traditional supernatural beliefs.

METHODS

The anonymized 16-item version of the Prodromal Questionnaire (PQ-16) was used to assess PLEs in three groups including individuals with religious beliefs (RB), belief in esoterism and paranormal phenomena (EB), and those embedded in scientific evidence approach and scepticism towards para-scientific theories (non-believers, NB). Male and female participants between 18 and 90 years were eligible for participation.

RESULTS

The sample comprised 159 individuals including 41 RB individuals, 43 EB individuals, and 75 NB individuals. The mean PQ-16 score of the EB individuals (6.86 ± 4.13) was significantly higher compared to NB individuals (3.43 ± 2.99) and to RB individuals (3.38 ± 3.23) with almost twice the score (both p-values < 0.001). There was no significant difference between the PQ-16 scores of the NB group and the RB group (p = 0.935). No significant impact of age (p = 0.330) and gender (p = 0.061) was found on the PQ16-Score. Group affiliation to esoterism was associated with a higher PQ-16 score compared to group affiliation to religious beliefs (p < 0.001) and group affiliation to scepticism (p = 0.011), while the latter two did not differ significantly (p = 0.735). No significant difference was found between the three groups in the degree of distress related to the affirmatively answered PQ-16 items (p = 0.74).

CONCLUSION

Under the assumption of a transdiagnostic psychosis phenotype, our findings provide more insight which subgroups within non-clinical samples have a higher likelihood of reporting PLEs.

Efficacy of a transdiagnostic, prevention-focused program for at-risk young adults: a waitlist-controlled trial

BACKGROUND

Prevention programs that are 'transdiagnostic' may be more cost-effective and beneficial, in terms of reducing levels of psychopathology in the general population, than those focused on a specific disorder. This randomized controlled study evaluated the efficacy of one such intervention program called Resilience Training (RT).

METHODS

College students who reported mildly elevated depressive or subclinical psychotic symptoms ('psychotic experiences' (PEs)) (n = 107) were randomized to receiving RT (n = 54) or to a waitlist control condition (n = 53). RT consists of a four-session intervention focused on improving resilience through the acquisition of mindfulness, self-compassion, and mentalization skills. Measures of symptoms and these resilience-enhancing skills were collected before and after the 4-week RT/waitlist period, with a follow-up assessment 12-months later.

RESULTS

Compared to the waitlist control group, RT participants reported significantly greater reductions in PEs, distress associated with PEs, depression, and anxiety, as well as significantly greater improvements in resilience, mindfulness, self-compassion, and positive affect, following the 4-week RT/waitlist period (all p < 0.03). Moreover, improvements in resilience-promoting skills were significantly correlated with symptom reductions (all p < 0.05). Lastly, the RT-related reductions in PEs and associated distress were maintained at the 12-month follow-up assessment.

CONCLUSIONS

RT is a brief, group-based intervention associated with improved resilience and reduced symptoms of psychopathology, with sustained effects on PEs, in transdiagnostically at-risk young adults. Follow-up studies can further assess the efficacy of RT relative to other interventions and test whether it can reduce the likelihood of developing a serious mental illness.

Prevalence, incidence, and persistence of psychotic experiences in the general population: results of a 9-year follow-up study

BACKGROUND

Psychotic experiences (PEs) frequently occur and are associated with a range of negative health outcomes. Prospective studies on PEs are scarce, and to date no study investigated PE prevalence, incidence, persistence, their risk indicators, and psychiatric comorbidity, in one dataset. Furthermore, most studies are based on self-report, and it is unclear how this compares to clinical interviews.

METHODS

Data are used from the Netherlands Mental Health Survey and Incidence Study-2 (NEMESIS-2), a psychiatric cohort study among a representative sample of adults (baseline characteristics: N = 6646; 49.6% female; 18-64 years). Results are presented for self-reported and clinically validated PEs. Associations are assessed for mental disorders, socio-demographic, vulnerability, physical health, and substance use factors.

RESULTS

Based on self-report, at baseline 16.5% of respondents had at least one PE in their lifetime, of those, 30.1% also reported a PE at 3-year follow-up. 4.8% had a first PE at 3-year follow up. The 3-year prevalence of PE was associated with almost all studied risk indicators. Generally, the strongest associations were found for mental health disorders. Prevalence and incidence rates were two to three times higher in self-report than in clinical interview but results on associated factors were similar.

CONCLUSIONS

Validated prevalence and incidence estimates of PE are substantially lower than self-reported figures but results on associated factors were similar. Therefore, future studies on associations of PEs can rely on relatively inexpensive self-reports of PEs. The associations between PE and mental disorders underline the importance of assessment of PE in general practice.

Detecting anomalous experiences in the community: The Transpersonal Experiences Questionnaire (TEQ)

OBJECTIVES

There is growing recognition of the value of researching anomalous experiences in the general population to aid our understanding of the psychosis continuum. There are key differences in aims, foci and epistemologies of existing measures, with varying utility for specific research designs. This study addresses gaps in the literature by developing a measure of anomalous experiences with utility for longitudinal (time-sensitive) research, and with particular reliability for people towards the upper (high scoring) end of the continuum.

METHODS

An online sample was recruited from the general population to provide questionnaire data for two study parts: (A) item selection and (B) psychometric evaluation. For Part A, both classical test theory and item response theory methods were used to select which items to be included from an initial pool of 57, generated from individuals with persistent anomalous experiences. For Part B, psychometric properties of the resulting measure were evaluated using exploratory and confirmatory factor analysis and tests of reliability and validity.

RESULTS

Scores were provided by 532 participants, from which a 19-item scale, the Transpersonal Experiences Questionnaire (TEQ), was developed. The TEQ was found to be a unidimensional scale, with satisfactory internal consistency (0.85), good test-retest reliability and convergent validity.

CONCLUSIONS

The TEQ can be used as a unidimensional scale to detect anomalous experiences in the general population, with particular reliability for people with higher incidence of these experiences.

Visual illusions in young people reporting psychotic-like experiences

BACKGROUND AND OBJECTIVES

A disruption in the co-ordination of bottom-up and top-down processing is thought to underlie anomalous perceptual experiences in psychosis. Visual illusions represent a valuable methodology in exploring this disruption. Here, we examined visual illusions in a group of young people having psychotic-like experiences. We also examined the relationship between illusion susceptibility and appraisal of psychotic-like experiences as well as depression, anxiety and stress levels.

METHOD

25 young people reporting psychotic-like experiences and 53 healthy participants performed an adjustment task that measured susceptibility to a battery of 13 visual illusions. Levels of depression, anxiety and stress were quantified in both groups. The clinical group also completed measures examining frequency, appraisals and emotional responses to psychotic-like experiences.

RESULTS

A general increase of illusion susceptibility was found in the clinical group compared to the control group. However, when depression, anxiety and stress levels were controlled for, this difference disappeared. Stress turned out to be the best predictor of illusion susceptibility in the clinical group, whereas anomalous experiences, depression and anxiety were unrelated to overall illusion strength.

LIMITATIONS

This study is limited to young participants reporting significant mental health difficulties and psychotic-like experiences. Findings should be replicated in an Ultra High Risk (prodromal) group.

CONCLUSIONS

Increased levels of stress explained the enhanced vulnerability to illusions in the clinical group. This increased susceptibility suggests a perceptual style that relies too heavily on prior expectations at the expense of the true sensory evidence, potentially leading to an altered perceptual experience of the world.

Empirically driven transdiagnostic stages in the development of mood, anxiety and psychotic symptoms in a cohort of youth followed from birth

Staging models with transdiagnostic validity across mood, psychotic, and anxiety disorders could advance early intervention efforts as well as our understanding of the common underpinnings of such psychopathology. However, there are few well-supported operationalisations for such transdiagnostic models, particularly in community-based samples. We aimed to explore the inter-relationships among mood, psychotic, and anxiety symptom stages, and their common risk factors to develop data-informed transdiagnostic stages. We included participants from the Avon Longitudinal Study of Parents and Children (ALSPAC), a prospective ongoing birth cohort study. We developed operational thresholds for stages of depressive, hypomanic, anxiety, and psychotic symptoms based on the existing literature, refined further by expert consensus. We selected 1b level as the primary stage or outcome of interest. This represents moderate symptoms that are likely to be associated with the onset of the need for clinical mental health care. We used questionnaire and clinic data completed by young people ages 18 and 21 years. We used descriptive methods and network analyses to examine the overlap among Stage 1b psychopathology. We then examined the patterns of relationships between several risk factors and 1b stages using logistic regressions. Among 3269 young people with data available to determine all symptom stages, 64.3% were female and 96% Caucasian. Descriptive and network analyses indicated that 1b level depressive, anxiety, and psychotic symptom stages were inter-related while hypomania was not. Similarly, anxiety, depressive, and psychotic 1b stages were associated with the female sex, more emotional and behavioral difficulties in early adolescence, and life events in late adolescence. Hypomania was not related to any of these risk factors. Given their inter-relationships and similar risk factors, anxiety, psychotic and depressive, symptoms could be combined to form a transdiagnostic stage in this cohort. Such empirical transdiagnostic stages could help with prognostication and indicated prevention in youth mental health.

Racial microaggressions and major discriminatory events explain ethnoracial differences in psychotic experiences

Few empirical studies have examined whether exposure to major racial discrimination explains ethnoracial disparities in psychosis outcomes and none to our knowledge have done so in the U.S. or have examined the role of other forms of racism such as racial microaggressions. The present study examined ethnoracial differences in self-reported psychotic experiences (PE) among 955 college students in an urban environment in the Northeastern U.S., and the degree to which major experiences of racial discrimination and racial microaggressions explains ethnoracial differences in PE. Mean scores on self-report inventories of PE and distressing PE (i.e., Prodromal Questionnaire (PQ)), major experiences of racial discrimination (EOD), and racial and ethnic microaggressions (REMS) were compared across 4 ethnoracial groups (White, Black, Asian, and Latina/o). Results from parallel mediation linear regression models adjusted for immigrant status, age, gender, and family poverty using the Hayes PROCESS application indicated ethnoracial differences in PE were explained independently by both forms of racism. Specifically, Black young people reported higher mean levels of PE, and distressing PE than both White and Latina/o people and the difference in PE between Black and White and Black and Latino/a young people was significantly explained by both greater exposure to racial microaggressions and major racial discriminatory experiences among Black people. This study re-emphasizes the explanatory role of racism, in its multiple forms, for psychosis risk among Black young populations in the US. Anti-racism interventions at both structural and interpersonal levels are necessary components of public health efforts to improve mental health in Black populations.

Psychotic-like experiences as a co-occurring psychopathological indicator of multi-dimensional affective symptoms: Findings from a cross-sectional survey among college students

BACKGROUND

Although connections between psychotic-like experiences (PLEs) and a series of non-psychotic disorders have been widely explored in previous research, it is unclear whether PLEs could act as a co-occurring psychopathological indicator of multi-dimensional affective symptoms.

METHODS

A total of 4761 students took part in an online survey which assessed the frequency of PLEs and three types of affective symptoms over lifetime. Binary logistic regression models were used to examine associations between PLEs and each type of affective symptom. Network analysis was conducted to explore the relationship among three subtypes of PLEs - persecutory ideation (PI), bizarre experiences (BEs) and perceptual abnormalities (PAs), and different types of affective symptoms.

RESULTS

The results showed that compared with the non-PLEs group, the PLEs group suffered significantly higher risk of experiencing three types of affective symptoms, including manic symptoms [adjusted odds ratio (aOR) 11.50, 95 % confidence interval (CI) (4.59-28.81)], depressive symptoms [aOR 7.28, 95 % CI (4.98-10.66)] and anxiety symptoms [aOR 4.47, 95 % CI (3.10-6.43)]. In the network model, bizarre experiences were the most critical central symptom. Both depressive and anxiety symptoms were most strongly associated with persecutory ideation while manic symptoms were most closely related to bizarre experiences.

LIMITATIONS

Cross-sectional data and self-reported symptoms.

CONCLUSIONS

These findings suggest that PLEs are a vital co-occurring indicator of multi-dimensional affective symptoms and show its enormous potential as a target for a host of mental health problems. Further investigation may shed light on the aetiology of the relationship between different subtypes of PLEs and affective symptoms.

Association between thyroid hormones and comorbid psychotic symptoms in patients with first-episode and drug-naïve major depressive disorder

Thyroid dysfunction is common in major depressive disorder (MDD) patients; however, its relationship with psychotic depression (PD) remains unclear. We aimed to assess thyroid hormones in 1718 first episode drug naïve (FEND) MDD patients and to determine their association with PD. The positive subscale of the Positive and Negative Symptom Scale (PANSS-P), Hamilton Anxiety Rating Scale (HAMA), and Hamilton Depression Rating Scale (HAMD) were used to detect clinical symptoms. The serum levels of free triiodothyronine (FT3), free thyroxine (FT4), thyroid stimulating hormone (TSH), anti-thyroglobulin (TgAb), and thyroid peroxidases antibody (TPOAb) were assessed. The logistic regression model was conducted to determine risk factors for PD, and the Area Under the Curve (AUC) was used to test the performance of this model. 171 (10%) patients were identified as having PD. Serum levels of TSH, TgAb, and TPOAb displayed small-to-moderate associations with PANSS-P. HAMA score, HAMD score, and TSH levels were independently associated with PD. The regression model had excellent power to distinguish PD patients from non-PD patients with an AUC value of 0.93. Our study suggests TSH levels and severity of depression and anxiety symptoms were independent risk factors for PD. Regular thyroid function tests may help early detect PD.

Genetic contributions to transdiagnostic symptom dimensions in patients with major depressive disorder, bipolar disorder, and schizophrenia spectrum disorders

Major depressive disorder (MDD), bipolar disorder (BD), and schizophrenia spectrum disorders (SZ) exhibit considerable phenotypic and genetic overlap. However, the contribution of genetic factors to their shared psychopathological symptom dimensions remains unclear. The present exploratory study investigated genetic contributions to the symptom dimensions "Depression", "Negative syndrome", "Positive formal thought disorder", "Paranoid-hallucinatory syndrome", and "Increased appetite" in a transdiagnostic subset of the German FOR2107 cohort (n = 1042 patients with MDD, BD, or SZ). As replication cohort, a subset of the German/Austrian PsyCourse study (n = 816 patients with MDD, BD, or SZ) was employed. First, the relationship between symptom dimensions and common variants associated with MDD, BD, and SZ was investigated via polygenic risk score (PRS) association analyses, with disorder-specific PRS as predictors and symptom dimensions as outcomes. In the FOR2107 study sample, PRS for BD and SZ were positively associated with "Positive formal thought disorder", the PRS for SZ was positively associated with "Paranoid-hallucinatory syndrome", and the PRS for BD was negatively associated with "Depression". The effects of PRS for SZ were replicated in PsyCourse. No significant associations were observed for the MDD PRS. Second, genome-wide association studies (GWAS) were performed for the five symptom dimensions. No genome-wide significant associations and no replicable suggestive associations (p < 1e-6 in the GWAS) were identified. In summary, our results suggest that, similar to diagnostic categories, transdiagnostic psychiatric symptom dimensions are attributable to polygenic contributions with small effect sizes. Further studies in larger thoroughly phenotyped psychiatric cohorts are required to elucidate the genetic factors that shape psychopathological symptom dimensions.

Substance use and psychotic-like experiences in young people: a systematic review and meta-analysis

This study aimed to systematically review and synthesise the available evidence on the prevalence and associations between psychotic-like experiences (PLEs) and substance use in children and adolescents aged ⩽17 years, prior to the typical age of development of prodromal symptoms of psychosis. As substance use has been associated with earlier age of psychosis onset and more severe illness, identifying risk processes in the premorbid phase of the illness may offer opportunities to prevent the development of prodromal symptoms and psychotic illness. MEDLINE, PsycINFO, and CINAHL databases were searched for chart review, case-control, cohort, twin, and cross-sectional studies. Study reporting was assessed using the Strengthening the Reporting of Observational Studies in Epidemiology (STROBE) checklist, and pooled evidence was evaluated using the Grading of Recommendations Assessment, Development and Evaluation (GRADE) approach. Searches identified 55 studies that met inclusion criteria. Around two-in-five substance users reported PLEs [rate = 0.41, 95% confidence interval (CI) 0.32-0.51; low quality evidence], and one-in-five with PLEs reported using substances (rate = 0.19, 95% CI 0.12-0.28; moderate-to-high quality evidence). Substance users were nearly twice as likely to report PLEs than non-users [odds ratio (OR) 1.77, 95% CI 1.55-2.02; moderate quality evidence], and those with PLEs were twice as likely to use substances than those not reporting PLEs (OR 1.93, 95% CI 1.55-2.41; very low quality evidence). Younger age was associated with greater odds of PLEs in substance users compared to non-users. Young substance users may represent a subclinical at-risk group for psychosis. Developing early detection and intervention for both substance use and PLEs may reduce long-term adverse outcomes.

Psychosocial factors associated with the risk of developing psychosis in a Mexican general population sample

Epidemiological evidence has linked an array of sociodemographic and psychosocial factors with an increased risk of developing psychosis. However, research in samples from low- and middle-income countries is still scarce. This study used a Mexican sample to explore (i) sociodemographic and psychosocial differences between individuals with and without a positive screen for Clinical High-Risk for psychosis (CHR), and (ii) sociodemographic and psychosocial factors associated with screening positive for CHR. The sample consisted of 822 individuals from the general population who completed an online survey. Of the participants, 17.3% (n = 142) met the CHR screening criteria. Comparisons between those who screened positive (CHR-positive group) and those who did not (Non-CHR group) showed that participants in the CHR-positive group were younger, had a lower educational level, and reported more mental health problems than the Non-CHR group. Furthermore, relative to the Non-CHR group, the CHR-positive group had a greater prevalence of medium/high risk associated with cannabis use, a higher prevalence of adverse experiences (bullying, intimate partner violence, and experiencing a violent or unexpected death of a relative or friend), as well as higher levels of childhood maltreatment, poorer family functioning, and more distress associated with the COVID-19 pandemic. Groups did not differ in sex, marital/relationship status, occupation, and socio-economic status. Finally, when examined in multivariate analyses, the variables associated with screening positive for CHR were: having an unhealthy family functioning (OR = 2.75, 95%CI 1.69-4.46), a higher risk associated with cannabis use (OR = 2.75, 95%CI 1.63-4.64), a lower level of education (OR = 1.55, 95%CI 1.003-2.54), having experienced a major natural disaster (OR = 1.94, 95%CI 1.18-3.16), having experienced a violent or unexpected death of a relative or friend (OR = 1.85, 95%CI 1.22-2.81), higher levels of childhood emotional abuse (OR = 1.88, 95%CI 1.09-3.25), physical neglect (OR = 1.68, 95%CI 1.08-2.61), and physical abuse (OR = 1.66, 95%CI 1.05-2.61), and higher COVID-related distress (OR = 1.10, 95%CI 1.01-1.20). An older age was a protective factor for screening positive for CHR (OR = 0.96, 95%CI 0.92-0.99). Overall, the findings highlight the importance of examining potential psychosocial contributors to psychosis vulnerability across different sociocultural contexts to delineate risk and protective processes relevant to specific populations and better target preventive intervention efforts.

Modelling the temporal interplay between stress and affective disturbances in pathways to psychosis: an experience sampling study

BACKGROUND

One putative psychological mechanism through which momentary stress impacts on psychosis in individuals with increased liability to the disorder is via affective disturbance. However, to date, this has not been systematically tested. We aimed to investigate whether (i) cross-sectional and temporal effects of momentary stress on psychotic experiences via affective disturbance, and (ii) the reverse pathway of psychotic experiences on stress via affective disturbance were modified by familial liability to psychosis.

METHODS

The Experience Sampling Method was used in a pooled data set of six studies with three groups of 245 individuals with psychotic disorder, 165 unaffected first-degree relatives, and 244 healthy control individuals to index familial liability. Multilevel moderated mediation models were fitted to investigate indirect effects across groups cross-sectionally and multilevel cross-lagged panel models to investigate temporal effects in the proposed pathways across two measurement occasions.

RESULTS

Evidence on indirect effects from cross-sectional models indicated that, in all three groups, effects of stress on psychotic experiences were mediated by negative affect and, vice versa, effects of psychotic experiences on stress were mediated by negative affect, with all indirect effects being weakest in relatives. Longitudinal modelling of data provided no evidence of temporal priority of stress in exerting its indirect effects on psychotic experiences via affective disturbance or, vice versa.

CONCLUSIONS

Our findings tentatively suggest a rapid vicious cycle of stress impacting psychotic experiences via affective disturbances, which does, however, not seem to be consistently modified by familial liability to psychosis.

Emotion regulation and delusion-proneness relate to empathetic tendencies in a transdiagnostic sample

Empathetic tendencies (i.e., perspective taking and empathic concern) are a key factor in interpersonal relationships, which may be impacted by emotion regulation (i.e., reappraisal and suppression) and mental health symptoms, such as psychotic-like experiences. However, it is unclear if certain psychotic-like experiences, such as delusion-proneness, are still associated with reduced empathetic tendencies after accounting for emotion regulation style and dimensions of psychopathology that are often comorbid. In the current study, linear models tested these associations in a transdiagnostic community sample (N = 128), using the Interpersonal Reactivity Index (IRI), Emotion Regulation Questionnaire, and the Peter's Delusion Inventory. Results indicated that perspective taking was positively associated with reappraisal and negatively associated with delusion-proneness, after controlling for age, sex, race, intelligence, and symptoms of anxiety and depression. A significant change in R 2 supported the addition of delusion-proneness in this model. Specificity analyses demonstrated perspective taking was also negatively associated with suppression, but this relationship did not remain after accounting for the effects of reappraisal and delusion-proneness. Additional specificity analyses found no association between empathic concern and reappraisal or delusion-proneness but replicated previous findings that empathic concern was negatively associated with suppression. Taken together, delusion-proneness accounts for unique variance in perspective taking, which can inform future experimental research and may have important implications for psychosocial interventions.

Psychotic experiences in the general population, a review; definition, risk factors, outcomes and interventions

Psychotic experiences (PE) are common in the general population, in particular in childhood, adolescence and young adulthood. PE have been shown to be associated with an increased risk for later psychotic disorders, mental disorders, and poorer functioning. Recent findings have highlighted the relevance of PE to many fields of healthcare, including treatment response in clinical services for anxiety & depression treatment, healthcare costs and service use. Despite PE relevance to many areas of mental health, and healthcare research, there remains a gap of information between PE researchers and experts in other fields. With this review, we aim to bridge this gap by providing a broad overview of the current state of PE research, and future directions. This narrative review aims to provide an broad overview of the literature on psychotic experiences, under the following headings: (1) Definition and Measurement of PE; (2) Risk Factors for PE; (3) PE and Health; (4) PE and Psychosocial Functioning; (5) Interventions for PE, (6) Future Directions.

Psychotic-like experiences of young adults in the general population predict mental disorders

Psychotic-like experiences (PLEs) have been identified as risk markers for psychotic disorders and may indicate an individual's susceptibility to mental disorders in general. We examined whether 23 PLEs (assessed with M-CIDI questionnaire) reported in young adulthood (n = 1313) predict subsequent psychotic or any mental disorders in the general population. We also investigated whether these possible associations are explained by general psychological distress assessed with the General Health Questionnaire-12 (GHQ-12). The register follow-up period spanned 10-12 years. In Cox regression models, PLEs predicted subsequent psychotic disorders (n = 12) when the effects of age, sex, education, and marital status were adjusted for, but not when general psychological distress was added to the model. Having any mental disorders during follow-up (n = 91) was predicted by PLEs reported at a younger age, when controlling for age, sex, education, marital status, and general psychological distress. In line with earlier results in other age groups, PLEs can be seen as a sign of vulnerability to not just psychotic but all mental disorders during the following years also among young adults in the general population. PLEs were a predictive marker of general psychopathology independently from general psychological distress.

'Thinking about Them is only making me feel worse'. The mediating role of metacognitive factors in the relationship between paranoia-like beliefs and psychopathology symptoms in a community sample

INTRODUCTION

Paranoia in community samples is associated with higher levels of depression, anxiety symptoms and suicidality. The metacognitive model assumes the role of metacognitive factors in these associations. Positive and negative metacognitive beliefs (PMB and NMB, respectively) and cognitive-attentional syndrome (CAS) are to mediate between paranoia-like beliefs and psychopathology symptoms. The current study is an attempt to test this prediction.

METHODS

A cross-sectional community study with n = 840 participants. We used R-GPTS's persecutory subscale to measure paranoia-like beliefs, CAS-1 for CAS and metacognitive beliefs and SCL-27-plus for psychopathology symptoms.

RESULTS

Indirect effects of PMB, CAS and NMB accounted for 22% to 56% (CI 95%) of total effects of relationships between paranoia-like beliefs and vegetative symptoms, symptoms of social phobia, agoraphobia, depression and suicidality screening.

CONCLUSIONS

We demonstrated that PMB, CAS and NMB mediate between paranoia-like beliefs and various psychopathological symptoms, as predicted by the metacognitive model of psychopathology. We also uncovered other indirect effects, including negative mediation effect of PMB on the relationship between paranoia-like beliefs and depressive symptoms and suicidality.

Association between incarceration and psychotic experiences in a general population sample

Incarceration of individuals with mental disorders is an important public health topic. While incarceration appears to be associated with schizophrenia and related psychotic disorders, to the best of our knowledge, no study has examined the association between incarceration and psychotic experiences (PEs). The present study aimed to examine whether individuals with PEs had higher odds of incarceration among a general population sample using data from Baltimore and New York City (N = 974). We fitted three regression models to examine the association between incarceration and PEs, using hierarchical adjustments for sociodemographic factors, adverse childhood experiences, and neighborhood disruption. The odds ratio (OR) for incarceration was attenuated with inclusion of more covariates in the model but remained statistically significant even at the highest level of adjustment (OR = 2.12, 95% CI = 1.30 to 3.46). Findings were similar when individually examining delusional mood, delusions of reference and persecution, and hallucination. For delusions of control, a significant association was not found in the highest level of adjustment. The present study provides novel information on the association between incarceration and PEs, adjusted for sociodemographic and psychosocial confounders. Taken in the context of prior studies, these data further support the need to address the high prevalence of psychosis across all aspects of the criminal justice system. Future studies should employ longitudinal data and objective outcome measurements.

Plasma lipid alterations in young adults with psychotic experiences: A study from the Avon Longitudinal Study of Parents and Children cohort

BACKGROUND

Psychotic experiences (PEs) are associated with an increased risk of future psychotic and non-psychotic mental disorders. The identification of biomarkers of PEs may provide insights regarding the underlying pathophysiology.

METHODS

The current study applied targeted lipidomic approaches to compare plasma lipid profiles in participants from the Avon Longitudinal Study of Parents and Children (ALSPAC) cohort who did (n = 206) or did not (n = 206) have PEs when aged approximately 24 years.

RESULTS

In total, 202 lipids including 8 lipid classes were measured by using ultra-high-performance liquid chromatography-quadrupole time-of-flight mass spectrometry (UHPLC-QTOF-MS). Eight lipid clusters were generated. Thirteen individual lipids were nominally significantly higher in the PEs group compared to the control group. After correction for multiple comparisons, 9 lipids comprising 3 lysophosphatidylcholines (LPCs), 2 phosphatidylcholines (PCs) and 4 triacylglycerols (TGs) remained significant. In addition, PEs cases had increased levels of TGs and LPCs with a low double bond count.

CONCLUSIONS

These findings indicate plasma lipidomic abnormalities in individuals experiencing PEs. The lipidomic profile measures could aid our understanding of the underlying pathophysiological mechanisms.

Anxiety symptoms, rule learning, and cognitive flexibility in non-clinical psychosis

Individuals with psychotic-like experiences (PLEs) represent a critical group for improving the understanding of vulnerability factors across the psychosis continuum. A growing body of literature has identified functional deficits associated with PLEs. However, it is unclear if such deficits purely reveal the underlying psychosis vulnerability or if they are also linked with comorbid anxiety symptoms. Although anxiety disorders are often associated with impairments in psychosis-risk, symptoms of anxiety may facilitate executive functioning in certain psychosis groups. The Community Assessment of Psychic Experiences was completed to assess psychosis-like symptoms in a total of 57 individuals, and its median score was used to categorize PLE groups (high-PLE = 24, low-PLE = 33). Anxiety symptoms were measured via the Beck Anxiety Inventory, and cognitive flexibility was measured by the Penn Conditional Exclusion Test. The high-PLE group endorsed more anxiety symptoms, demonstrated poorer accuracy and efficiency on the cognitive task, and made more perseverative errors compared to the low-PLE group. Within the high-PLE group, higher levels of anxiety symptoms were associated with better performance and less perseverative errors compared to individuals with lower levels of anxiety symptoms. Conversely, greater anxiety symptoms were associated with poorer performance in the low-PLE group. Taken together, these findings provide a preliminary support for a potential psychosis vulnerability × anxiety symptom interaction. Given the interest in the psychosis continuum and potential treatment implications, the present findings warrant replication efforts.

Metacognitive Abilities as a Protective Factor for the Occurrence of Psychotic-Like Experiences in a Non-clinical Population

Psychotic-like experiences (PLEs) are a phenomenon that occurs in the general population experiencing delusional thoughts and hallucinations without being in a clinical condition. PLEs involve erroneous attributions of inner cognitive events to the external environment and the presence of intrusive thoughts influenced by dysfunctional beliefs; for these reasons, the role played by metacognition has been largely studied. This study investigates PLEs in a non-clinical population and discriminating factors involved in this kind of experience, among which metacognition, as well as psychopathological features, seems to have a crucial role. The aim of this study was to extend the knowledge about the relationship between metacognition, psychopathology, and PLEs, orienting the focus on metacognitive functioning. The sample consisted of 207 Italian participants (men = 32% and women = 68%) voluntarily recruited online, who gave consent to participate in the study. The average age of the sample was 32.69 years (SD: 9.63; range: 18-71). Subjects affected by psychosis, neurological disease, and drug addiction were excluded from the analyses. The following scales were used to investigate PLEs: Peters et al. Delusions Inventory (PDI), Launay-Slade Hallucinations Scale-Extended Revised (LSHSE), Prodromal Questionnaire-Brief (PQ-B), and Revised Hallucination Scale (RHS). To assess general psychopathological features, the Behavior and Symptom Identification Scale (BASIS-32) was administrated. The Metacognition Self-Assessment Scale (MSAS) was chosen to evaluate metacognitive functioning. From hierarchical regression analyses, it emerged that the presence of anxiety, depression, and impulsive/addictive symptoms constitute a remarkable vulnerability factor for PLEs, in line with previous evidence regarding the relationship between general psychopathology and PLEs. Metacognition negatively predicts PLEs, and its presence does not affect the significance of psychopathological variables, suggesting that metacognitive abilities seem to play a protective role for the occurrence of PLEs among non-clinical individuals, and such ability operates as an independent predictor along with other variables. These results are explained by the role of metacognitive functions, which allow individuals to operate many mental processes such as interpreting sensorial events as real or illusory, understanding behaviors, thoughts, and drives of others, and questioning the subjective interpretation of facts.

The prevalence of physical multimorbidity among people with non-affective psychotic disorders 10 years after first diagnosis: a matched retrospective cohort study

AIMS

The higher prevalence of chronic physical health conditions among people with psychotic disorders may result in a reduced life expectancy as compared to the general population. More research is needed on the risk of multiple co-occurring chronic health conditions, known as multimorbidity, for people with psychotic disorders.

METHODS

We conducted a matched retrospective cohort study to quantify the prevalence of multimorbidity and associated factors among people with psychotic disorders over the 10-year period following first diagnosis, relative to those without psychosis. Data from an early psychosis intervention program in London, Canada were linked to population-based health administrative data to identify patients with first-episode psychosis (n = 439), and a comparison group from the general population (n = 1759) matched on age, sex, and postal code. We followed the cohort for 10 years to ascertain the prevalence of multimorbidity. We compared people with and without psychosis using modified Poisson regression models, and explored risk factors for multimorbidity among those with psychotic disorders.

RESULTS

People with psychotic disorders may have a 26% higher prevalence of multimorbidity 10 years following first diagnosis, although our findings include the possibility of a null effect (PR = 1.26, 95% CI 0.96-1.66). People with psychosis living in areas with the highest levels of material deprivation had a threefold higher prevalence of multimorbidity as compared to those in the lowest areas of material deprivation (PR = 3.09, 95% CI 1.21-7.90).

CONCLUSION

Multimorbidity is prevalent among those with psychosis, and assessment for chronic health conditions should be integrated into clinical care for younger populations with psychotic illness.

Psychosis risk among pregnant women in Ghana

Introduction

Psychotic illness, although is rare, has been reported in the perinatal period. Individuals diagnosed with psychotic illness tend to first exhibit psychotic-like experiences (PLEs), defined as subclinical psychotic symptoms that occur outside the context of sleep or drug use. However, there is a paucity of empirical data on PLEs in pregnancy to advance scholarly discourse and support professional practice. The current study investigated the prevalence and correlates of PLEs among pregnant women in Ghana, a West African state.

Design

A cross-sectional survey design was used to collect data from 702 pregnant women who responded to measures of PLEs, COVID-19 concerns and behavioral maladies such as anxiety and depressive symptoms. Descriptive and inferential statistics, namely chi square, exploratory factor analysis, MANOVA and multinomial logistic regression were used to analyze the data.

Results

The results showed that 54.2%, 27.3% and 18.5% of participants were at no/low, moderate and high risk for psychosis, respectively. A total of 44.4% participants were not distressed by PLEs, whereas 32.2% and 23.4% were a bit/quite and very distressed, respectively. Psychosis risk was elevated among pregnant women who were more concerned about the COVID-19 effects, scored high in suicidal ideation, depressive symptoms and sleep difficulties.

Conclusion

The study showed that psychosis risk is present in pregnancy.

Implications

Screening for psychosis risk in pregnancy should be prioritized for pregnant women with behavioral maladies, including suicidal tendencies, depressive symptoms, sleep difficulties and heightened concerns about COVID-19.

The profile of unusual beliefs associated with metacognitive thinking and attributional styles

Cognitive interpretations of daily events may differ in people from the general population who hold unusual beliefs. It is also important to understand whether different belief profiles exist to appreciate which patterns of beliefs are less psychologically healthy. Cluster analysis was used to form unusual belief profiles in a general population sample (n = 578; M_age = 22 years, SD = 6.98; 80% female) across paranoid, paranormal, and magical ideation beliefs, and we assessed whether they differed in attribution style and metacognitive beliefs about worry. Four clusters were formed: low on all measures (low all); high on all measures (high all); comparably higher on paranormal beliefs (paranormal group); and comparably higher on paranoid beliefs (paranoid group). For total Metacognitions Questionnaire‐30, the high all and high paranoid clusters did not differ, and both clusters scored higher than the high paranormal group, who all scored higher than the low all cluster. For attributional styles (Attributional Styles Questionnaire), lower scores on internal positive attribution were found for the high all and high paranoid clusters compared to the low all and high paranormal clusters. The high paranormal cluster had higher scores than the high paranoid cluster on self‐serving bias. Differences in attributional style appeared to be driven by mental health diagnosis. Our results suggest different profiles of unusual beliefs are detectable in the general population that differ in their metacognitive beliefs and perceived causation of events in their environment. Future studies investigating delusional proneness need to consider multiple unusual beliefs as well as assessing mood state and distress.

Psychotic-like experiences and associated socio-demographic factors among pregnant women in each trimester in China

OBJECTIVE

Psychotic-like experiences (PLEs) are quite common in the general populations without a clinical diagnosis, but pregnant women have been neglected in earlier literature. This study aimed to investigate the prevalence and correlates of PLEs among pregnant women without previous psychiatric history in each trimester.

METHOD

A total of 950 pregnant women participated in a cross-sectional survey, with social and demographic information collected. The Positive Subscale of Community Assessment of Psychic Experiences (CAPE) was used to measure PLEs, and the 7-item Generalized Anxiety Disorder Questionnaire (GAD-7) and the Edinburgh Postnatal Depression Scale (EPDS) were used to examine anxious and depressive symptoms, respectively. Logistic regression analyses were conducted to investigate the risk factors for pregnant women with PLEs.

RESULTS

In our study, 37.2% of the pregnant women in this sample experienced at least one episode of PLEs, while 4.3% reported "often" having PLEs. More pregnant women experienced PLEs, delusional experiences, and hallucinatory experiences in the first two trimesters than in the third trimester. Factors associated with a higher risk for more frequent PLEs include: rural setting, unplanned pregnancy, parity 1, and EPDS scores. High positive correlations were shown between frequency scores among experiences of PLEs and GAD-7 scores, EPDS scores.

CONCLUSION

Episodes of PLEs are common in Chinese pregnant women; however, only a small proportion has persistent PLEs. It is vital to pay attention to women with psychosis risk in pregnancy.

Testing extra-linearity across a psychosis continuum

BACKGROUND

It is unclear whether psychotic experiences (PEs) gradually merge into states of clinical psychosis along a continuum which correspond to a dimensional classification or whether latent classes appear above a certain severity threshold which correspond better to diagnostic categories of psychosis.

METHODS

Annual cross-sectional surveys, 2014-19, among Chinese undergraduates (N = 47,004) measured PEs, depression and etiological risk factors using standardized self-report instruments. We created a psychosis continuum with five levels and tested linear and extra-linear contrasts in associated etiological risk factors, before and after adjustment for depression. We carried out latent class analysis.

RESULTS

Categorical expression of psychosis, including hallucinations and delusions, nuclear symptoms, and nuclear symptoms and depression were found at severe level 5. Etiological risk factors which impacted linearly across the continuum were more common for depression. Child maltreatment impacted extra-linearly on both psychosis and depression. Family history of psychosis impacted linearly on psychosis; male sex and urban birth impacted extra-linearly and were specific for psychosis. Four latent classes were found, but only at level 5. These corresponded to nuclear schizophrenia symptoms, nuclear schizophrenia and depressive symptoms, severe depression, and an unclassified category with moderate prevalence of PEs.

CONCLUSION

Quantitative and qualitative changes in the underlying structure of psychosis were observed at the most severe level along a psychosis continuum, where four latent classes emerged. These corresponded to existing categorical classifications but require confirmation with clinical interview. PEs are non-specific and our findings suggest some are on a continuum with depression, whilst others are on a continuum with non-affective psychosis. Differing patterns of impact from etiological risk factors across the spectrum of psychopathology determine outcome at the most severe level of these continua.

Anomalous self-experiences (ASE) in relation to clinical high risk for psychosis (CHRP), childhood trauma and general psychopathology among adolescent and young adult help seekers

BACKGROUND

Anomalous self-experiences (ASE) are suggested as a phenotypic core feature of schizophrenia spectrum disorders and present in at risk samples as well. In our study, we investigated the relation between ASE and clinical high risk state for psychosis (CHRP) against the background of further influencing factors like childhood trauma and general psychopathology.

METHODS

126 help-seeking adolescents were included. CHR-P patients were identified using the Structured Interview for Psychosis-Risk Syndromes (SIPS). ASE were assessed with the Inventory of Psychotic-like Anomalous Self-Experiences (IPASE). Childhood trauma, depression and anxiety were assessed with well-established questionnaires (CTQ; PHQ-9; GAD-7).

RESULTS

CHR-P subgroup (n = 50, 39.7%) show significantly higher scores in IPASE total (t (81.07) = -5.150, p = .000) and CTQ total (t (85.95) = -2.75, p = .007) in comparison with the non CHR-P subgroup. Logistic regression analysis confirmed that IPASE total could predict CHR-P status (OR 1.03, 95% CI 1.01-1.04, p = .000). Furthermore, CTQ total and IPASE total show moderate to strong positive correlation (r = 0.44, p < .001) as well as CTQ total with both IPASE subdomains Cognition (r = 0.404, p < .001) and Self- Awareness (r = 0.443, p < .001).

CONCLUSION

The CHR-P subgroup shows significantly more ASE than the non CHR-P subgroup. Further, ASE predicted CHR-P status. Our results indicated that ASE could play a considerable role in the identification of high risk for developing schizophrenia spectrum disorder and could complement CHR-P testing. Importantly, it seems that ASE may be related to exposure to childhood trauma.

Changes of psychotic-like experiences and their association with anxiety/depression among young adolescents before COVID-19 and after the lockdown in China

OBJECTIVE

Lockdown policies during COVID-19 pandemic have potential adverse psychological impacts on youth. However, little is known about their influence on the changes of psychotic-like experiences (PLEs) among adolescents, nor about the possible association between changes in PLEs and changes in anxiety/depression symptoms. We investigated these two questions through a longitudinal comparative study.

METHODS

In total, 1825 adolescents were surveyed before COVID-19 and after the lockdown in China (T0, October 20th, 2019 and T1, May 18th, 2020). PLEs, anxiety, and depression were measured with paranoia, anxiety and depression subscales of the Mental Health Inventory of Middle school students (MMHI-60). Within-subjects Wilcoxon test, Spearman correlation test, and Kruskal-Wallis test were adopted.

RESULTS

Significant increase in adolescent PLEs scores was observed after the lockdown (Wilcoxon's w = 9.302, p < 0.001). We also found positive correlation between changes of PLEs and changes of anxiety/depression (Spearman's rho = 0.59/0.53, both p < 0.001). Furthermore, four PLEs trajectories were identified based on the report of PLEs at two timepoints: 60.4% with no PLEs, 9.3% remitted PLEs, 16.7% new PLEs, and 13.6% persistent PLEs. Significant difference was found in changes of anxiety/depression among four groups (p < 0.001); notably, the group with new-onset PLEs had the greatest exacerbation in anxiety/depression symptoms (both p Bonferroni <0.001).

CONCLUSIONS

This work is the first to identify increases in adolescent PLEs across the COVID-19 pandemic and suggested a close longitudinal association between PLEs and anxiety/depression. Our findings have implications for adolescent mental health crisis interventions during the pandemic.

Impact of urban birth and upbringing on expression of psychosis in a Chinese undergraduate population

BACKGROUND

Urban birth and upbringing show consistent associations with psychotic illness but the key urban exposures remain unknown. Associations with psychotic-like experiences (PEs) are inconsistent. These could be confounded by common mental disorders associated with PEs. Furthermore, associations between PEs and urban exposures may not extrapolate to psychotic disorders such as schizophrenia.

METHODS

Annual cross-sectional surveys among first year Chinese undergraduates 2014-2019 (n = 47,004). Self-reported, hierarchical categorisation of psychosis: from psychoticism, paranoid ideation, schizotypal symptoms, nuclear syndrome using SCL-90-R, to clinical diagnosis of schizophrenia. Depressive symptoms using PHQ 9. Dissociative symptoms and posttraumatic stress disorder (PTSD) measured using PCL-C. Etiological factors of family history and childhood disadvantage. We studied effects of urban birth, urban living and critical times of exposure in childhood on psychosis phenotypes.

RESULTS

Associations with urbanicity were found only after adjustments for depression. Urban birth was associated with paranoia (AOR 1.34, 1.18-1.53), schizotypal symptoms (AOR 1.59, 1.29-1.96), and schizophrenia (AOR 2.07, 1.10-3.87). The same phenotypes showed associations with urban residence > 10 years. Only schizophrenia showed an association with urban exposure birth-3 years (AOR 7.01, 1.90-25.86). Child maltreatment was associated with both psychosis and depression. Urbanicity measured across the total sample did not show any associations with demography, family history of psychosis, or child maltreatment. Sensitivity analysis additionally adjusting for dissociative symptoms and PTSD showed the same pattern of findings.

CONCLUSIONS

Urban birth and urban living showed a hierarchical pattern of increasing associations from paranoid ideation to schizotypal disorder to schizophrenia, confirming that associations for psychotic experiences could be extrapolated to schizophrenia, but only after adjusting for confounding from depression, dissociative symptoms and PTSD. Several etiological factors were the same for psychosis and depression. Future studies of PEs should adjust for confounding from common mental disorders and dissociative symptoms. Effects of urbanicity on psychosis were not explained by demography, family history of mental disorder, or child maltreatment.

Psychotic-like experiences among 9,564 Kenyan adolescents and young adults

OBJECTIVE

To investigate the prevalence and characteristics of psychotic-like experiences (PLE) in a large cohort of Kenyan adolescents and young adults.

METHOD

The Washington Early Recognition Center Affectivity and Psychosis (WERCAP) Screen was used to the study the 12-month prevalence of PLE's among 9,564 Kenyan youths (aged 15-25 yrs), and the rates of psychosis high-risk (HR) and medium-risk (MR) cases, based on cut-off scores. Relationships with clinical, demographic and economic profiles were investigated.

RESULTS

Across all participants, 72% reported having had at least one PLE over the last year. 4.6% and 30.6% were HR and MR based on symptom scores. There were similar PLE rates in females and males. PLE severity correlated with mood (r=0.67), stress (r=0.46), and autistic traits (r=0.18). PLE severity was also related to poverty, lower education attainment, and underemployment. Compared to controls, HR and MR youths were more likely to report lifetime substance use and to have more significant use.

CONCLUSION

Psychosis screening can provide valuable information about individuals and may help identify those who may require clinical assessment and intervention to improve outcomes. This is particularly relevant in many parts of Africa where the resources are limited for treating more advanced illness.

Nonclinical psychotic-like experiences and schizotypy dimensions: Associations with hippocampal subfield and amygdala volumes

Schizotypy and psychotic‐like experiences (PLE) form part of the wider psychosis continuum and may have brain structural correlates in nonclinical cohorts. This study aimed to compare the effects of differential schizotypy dimensions, PLE, and their interaction on hippocampal subfields and amygdala volumes in the absence of clinical psychopathology. In a cohort of 367 psychiatrically healthy individuals, we assessed schizotypal traits using the Oxford‐Liverpool Inventory of Life Experiences (O‐LIFE) and PLE using the short form of the Prodromal Questionnaire (PQ‐16). Based on high‐resolution structural MRI scans, we used automated segmentation to estimate volumes of limbic structures. Sex and total intracranial volume (Step 1), PLE and schizotypy dimensions (Step 2), and their interaction terms (Step 3) were entered as regressors for bilateral amygdala and hippocampal subfield volumes in hierarchical multiple linear regression models. Positive schizotypy, but not PLE, was negatively associated with left amygdala and subiculum volumes. O‐LIFE Impulsive Nonconformity, as well as the two‐way interaction between positive schizotypy and PLE, were associated with larger left subiculum volumes. None of the estimators for right hemispheric hippocampal subfield volumes survived correction for multiple comparisons. Our findings support differential associations of hippocampus subfield volumes with trait dimensions rather than PLE, and support overlap and interactions between psychometric positive schizotypy and PLE. In a healthy cohort without current psychosis risk syndromes, the positive association between PLE and hippocampal subfield volume occurred at a high expression of positive schizotypy. Further studies combining stable, transient, and genetic parameters are required.

Experiential avoidance mediates the association between paranoid ideation and depressive symptoms in a sample from the general population

Psychotic experiences are prevalent in the general population and are associated with negative outcomes, including depressive symptoms. The mechanisms underlying this relationship remain unclear, but new insights could be obtained by exploring the role of transdiagnostic processes such as experiential avoidance, defined as a person's attempts or desires to suppress unwanted internal experiences like thoughts, emotions, memories, or bodily sensations. Studies analyzing the link between negative emotional states and psychotic experiences are scant. We explored the association between a specific kind of psychotic experience (paranoid ideation), experiential avoidance, and depressive, anxiety, and stress symptoms in a sample from the general population. We found that experiential avoidance partially mediates the associations between paranoid ideation and stress and anxiety symptoms and that it fully mediates the association between paranoid ideation and depressive symptoms. Our results suggest that the presence of paranoid ideation and the usage of experiential avoidance to cope with it are vulnerability factors associated with psychological distress.

Psychopathological Syndromes Across Affective and Psychotic Disorders Correlate With Gray Matter Volumes

INTRODUCTION

More than a century of research on the neurobiological underpinnings of major psychiatric disorders (major depressive disorder [MDD], bipolar disorder [BD], schizophrenia [SZ], and schizoaffective disorder [SZA]) has been unable to identify diagnostic markers. An alternative approach is to study dimensional psychopathological syndromes that cut across categorical diagnoses. The aim of the current study was to identify gray matter volume (GMV) correlates of transdiagnostic symptom dimensions.

METHODS

We tested the association of 5 psychopathological factors with GMV using multiple regression models in a sample of N = 1069 patients meeting Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition (DSM-IV) criteria for MDD (n = 818), BD (n = 132), and SZ/SZA (n = 119). T1-weighted brain images were acquired with 3-Tesla magnetic resonance imaging and preprocessed with CAT12. Interactions analyses (diagnosis × psychopathological factor) were performed to test whether local GMV associations were driven by DSM-IV diagnosis. We further tested syndrome specific regions of interest (ROIs).

RESULTS

Whole brain analysis showed a significant negative association of the positive formal thought disorder factor with GMV in the right middle frontal gyrus, the paranoid-hallucinatory syndrome in the right fusiform, and the left middle frontal gyri. ROI analyses further showed additional negative associations, including the negative syndrome with bilateral frontal opercula, positive formal thought disorder with the left amygdala-hippocampus complex, and the paranoid-hallucinatory syndrome with the left angular gyrus. None of the GMV associations interacted with DSM-IV diagnosis.

CONCLUSIONS

We found associations between psychopathological syndromes and regional GMV independent of diagnosis. Our findings open a new avenue for neurobiological research across disorders, using syndrome-based approaches rather than categorical diagnoses.