Variation of subclinical psychosis across 16 sites in Europe and Brazil: findings from the multi-national EU-GEI study.

BACKGROUND: Incidence of first-episode psychosis (FEP) varies substantially across geographic regions. Phenotypes of subclinical psychosis (SP), such as psychotic-like experiences (PLEs) and schizotypy, present several similarities with psychosis. We aimed to examine whether SP measures varied across different sites and whether this variation was comparable with FEP incidence within the same areas. We further examined contribution of environmental and genetic factors to SP. METHODS: We used data from 1497 controls recruited in 16 different sites across 6 countries. Factor scores for several psychopathological dimensions of schizotypy and PLEs were obtained using multidimensional item response theory models. Variation of these scores was assessed using multi-level regression analysis to estimate individual and between-sites variance adjusting for age, sex, education, migrant, employment and relational status, childhood adversity, and cannabis use. In the final model we added local FEP incidence as a second-level variable. Association with genetic liability was examined separately. RESULTS: Schizotypy showed a large between-sites variation with up to 15% of variance attributable to site-level characteristics. Adding local FEP incidence to the model considerably reduced the between-sites unexplained schizotypy variance. PLEs did not show as much variation. Overall, SP was associated with younger age, migrant, unmarried, unemployed and less educated individuals, cannabis use, and childhood adversity. Both phenotypes were associated with genetic liability to schizophrenia. CONCLUSIONS: Schizotypy showed substantial between-sites variation, being more represented in areas where FEP incidence is higher. This supports the hypothesis that shared contextual factors shape the between-sites variation of psychosis across the spectrum.

Co-occurrence of borderline and schizotypal personality disorders: a scoping review.

BACKGROUND: The historical concept of borderline conditions refers to the pathology on the border between neurosis and psychosis. In DSM-III the conditions were divided into specific but also somewhat overlapping diagnostic criteria for Borderline Personality Disorder (BPD) and Schizotypal Personality Disorder (SPD). This phenomenological overlap, which results in co-occurrence of the two diagnoses, remains a clinical challenge to this day. METHODS: To address this issue we examined the co-occurrence of SPD and BPD according to the established DSM-IV/-5 diagnostic criteria. A literature search was conducted including studies that employed a structured interview with defined BPD and SPD criteria. RESULTS: Studies from 20 samples were included (i.e. 15 patients, 3 community and 2 forensic samples). For patients diagnosed primarily with BPD, 1-27% also met the criteria for SPD and for patients diagnosed primarily with SPD, 5 - 33% showed co-occurrence with BPD. In the forensic samples, co-occurrence for primary BPD was 10% and 67 - 82% for primary SPD. In the community samples, co-occurrence for primary BPD was 29% and 50% for primary SPD. The pattern of co-occurrence across community samples was particularly heterogeneous. CONCLUSION: The identified co-occurrences for BPD and SPD were considerably sample-dependent, and samples and measurements were generally too heterogeneous for a precise meta-analysis. Forensic and community samples generally showed higher co-occurrences, but these findings were characterized by potential methodological limitations.

Handedness and anxiety: a review.

Handedness is a core phenotype in clinical laterality research and several different disorders such as schizophrenia and autism spectrum disorders have been linked to a higher prevalence of non-right-handedness. Moreover, subclinical personality traits like schizotypy have been linked to a higher prevalence of non-right-handedness. The association with handedness is poorly understood for generalized anxiety disorder and specific phobias, as well as for state and trait anxiety and fear of specific stimuli in nonclinical samples. Therefore, we performed a narrative review of studies investigating handedness in anxiety disorders patients and studies that compared anxiety scores between different handedness groups. Unlike schizophrenia and autism spectrum disorders, there seems to be no strong association between anxiety disorders and handedness in adult patients, except for specific phobias. Studies often had small sample sizes and therefore a high risk to report spurious findings. Similar findings were reported in most non-clinical studies. Importantly, familial handedness affects phobia risk and antenatal maternal anxiety increased the probability of mixed-handedness. This suggests that a transgenerational, developmental perspective is essential to better understand the complex interrelations between handedness and anxiety. Familial and especially maternal handedness and anxiety disorders should be integrated into future studies on handedness and anxiety whenever possible.

Schizophrenia spectrum disorders in Denmark between 2000 and 2018: Incidence and early diagnostic transition.

BACKGROUND: Schizophrenia spectrum disorders (SSD) comprise a group of related mental disorders, which share clinical features and common genetic disposition, but it is unknown if there is a diagnostic transition between these disorders over time. We aimed to study the incidence at the first SSD diagnosis between 2000 and 2018, defined as schizophrenia, schizotypal or schizoaffective disorder, and the early diagnostic transition between these disorders. METHODS: Using Danish nationwide healthcare registers, we identified all individuals aged 15-64 years during the period from 2000 to 2018 in Denmark and calculated the yearly incidence rates for the specific SSDs. We studied the diagnostic pathways from the first ever diagnosis of an SSD across the subsequent two treatment courses with an SSD diagnosis to evaluate early diagnostic stability, and explore potential changes over time. RESULTS: Among 21,538 patients, yearly incidence rates per 10,000 individuals were similar during the observation period for schizophrenia (2000: 1.8; 2018: 1.6), lower for schizoaffective disorder (2000: 0.3; 2018: 0.1) and increasing for schizotypal disorder (2000: 0.7; 2018: 1.3). Among the subgroup of 13,417 individuals with three separate treatment courses, early diagnostic stability was present among 89.9% which differed between the disorders (schizophrenia: 95.4%; schizotypal disorder: 78.0%; schizoaffective disorder: 80.5%). Among 1352 (10.1%) experiencing an early diagnostic transition, 398 (3.0%) were diagnosed with schizotypal disorder after a schizophrenia or schizoaffective disorder diagnosis. CONCLUSION: This study provides comprehensive incidence rates for SSDs. The majority of patients experienced early diagnostic stability, but sizable proportions of people with initial schizophrenia or schizoaffective disorder are subsequently diagnosed with schizotypal disorder.

Parental mental disorders and offspring schizotypy in middle childhood: an intergenerational record linkage study.

PURPOSE: To investigate relationships between distinct schizotypy risk profiles in childhood and the full spectrum of parental mental disorders. METHODS: Participants were 22,137 children drawn from the New South Wales Child Development Study, for whom profiles of risk for schizophrenia-spectrum disorders in middle childhood (age ~ 11 years) were derived in a previous study. A series of multinomial logistic regression analyses examined the likelihood of child membership in one of three schizotypy profiles (true schizotypy, introverted schizotypy, and affective schizotypy) relative to the children showing no risk, according to maternal and paternal diagnoses of seven types of mental disorders. RESULTS: All types of parental mental disorders were associated with membership in all childhood schizotypy profiles. Children in the true schizotypy group were more than twice as likely as children in the no risk group to have a parent with any type of mental disorder (unadjusted odds ratio [OR] = 2.27, 95% confidence intervals [CI] = 2.01-2.56); those in the affective (OR = 1.54, 95% CI = 1.42-1.67) and introverted schizotypy profiles (OR = 1.39, 95% CI = 1.29-1.51) were also more likely to have been exposed to any parental mental disorder, relative to children showing no risk. CONCLUSION: Childhood schizotypy risk profiles appear not to be related specifically to familial liability for schizophrenia-spectrum disorders; this is consistent with a model where liability for psychopathology is largely general rather than specific to particular diagnostic categories.

Cumulative Environmental Risk in Early Life: Associations With Schizotypy in Childhood.

BACKGROUND AND HYPOTHESIS: Psychotic disorders are associated with a growing number of recognized environmental exposures. Cumulative exposure to multiple environmental risk factors in childhood may contribute to the development of different patterns of schizotypy evident in early life. Hypotheses were that distinct profiles of schizotypy would have differential associations with a cumulative score of environmental risk factors. STUDY DESIGN: We prospectively examined the relationship between 19 environmental exposures (which had demonstrated replicated associations with psychosis) measured from the prenatal period through to age 11 years, and 3 profiles of schizotypy in children (mean age = 11.9 years, n = 20 599) that have been established in population data from the New South Wales-Child Development Study. Multinomial logistic regression was used to examine associations between membership in each of 3 schizotypy profiles (true schizotypy, introverted schizotypy, and affective schizotypy) and exposure to a range of 19 environmental risk factors for psychosis (both individually and summed as a cumulative environmental risk score [ERS]), relative to children showing no risk. RESULTS: Almost all environmental factors were associated with at least 1 schizotypy profile. The cumulative ERS was most strongly associated with the true schizotypy profile (OR = 1.61, 95% CI = 1.52-1.70), followed by the affective (OR = 1.33, 95% CI = 1.28-1.38), and introverted (OR = 1.32, 95% CI = 1.28-1.37) schizotypy profiles. CONCLUSIONS: Consistent with the cumulative risk hypothesis, results indicate that an increased number of risk exposures is associated with an increased likelihood of membership in the 3 schizotypy profiles identified in middle childhood, relative to children with no schizotypy profile.

Schizotypal dimensions are associated with current but not former tobacco consumption.

OBJECTIVES: We aimed to study the relationship between tobacco smoking and attenuated psychosis measures taking into account several aspects of tobacco consumption that to date have not been explored and that could help understand this association, such as age of onset, the influence of former consumption and the duration of abstinence. METHODS: We investigated, in a sample of 580 students, the relationship between schizotypy (using the schizotypal personality questionnaire-brief in a Likert format) and smoking status, nicotine dependence (measured with the Fagerström test for nicotine dependence), age of onset of smoking and in former smokers, duration of smoking abstinence. RESULTS: 35.2% of the students were current smokers and 13.4% were former smokers. We found that current but not former smokers had higher scores of schizotypy (total, positive and disorganized) than non-smokers. We found no association between schizotypy scores and nicotine dependence or earlier age of onset of smoking. The duration of smoking abstinence, in former smokers, was inversely correlated to the score of positive and total schizotypy. CONCLUSIONS: Our results suggest that tobacco has a reversible effect on schizotypy, but more studies with a different design (controlled, longitudinal) and a more thorough exploration of potential confounders (e.g. cannabis) are needed before a firm conclusion can be reached.

Polygenic risk for schizophrenia as a moderator of associations between childhood trauma and schizotypy.

Recent evidence shows that genetic and environmental risk factors for psychotic disorders are associated with higher levels of schizotypy (or psychosis proneness) in the general population. However, little is known about how these risk factors interact. We specifically examined whether genetic loading for schizophrenia moderates the association between childhood trauma severity and schizotypy. Schizotypy was measured using the Schizotypal Personality Questionnaire (SPQ), and childhood trauma severity was measured with the Childhood Trauma Questionnaire (CTQ) among a total of 168 participants (comprising 51 healthy individuals, 56 diagnosed with schizophrenia, and 61 with bipolar disorder). Polygenic risk scores (PRS) for schizophrenia were calculated for all participants and examined as a potential moderator of associations between total scores on the CTQ and schizotypy total scores and dimensions (i.e., cognitive-perceptual, interpersonal, disorganised). Multiple linear regression models revealed associations between childhood trauma and all dimensions of schizotypy, but no associations between PRS and schizotypy. A significant interaction between PRS and childhood trauma was evident for the interpersonal and disorganised dimensions of schizotypy, as well as the total score, reflecting positive associations between childhood trauma severity and these two schizotypal dimensions, only for individuals with low or average PRS for schizophrenia. This suggests that trauma may be able to increase risk for psychosis independently of any genetic vulnerability. The present findings are consistent with the idea of several risk pathways for the development of psychotic disorders.

[Assessment of the initial period of schizotypal disorder in childhood]. / Otsenka nachal'nogo perioda shizotipicheskogo rasstroistva v detskom vozraste.

OBJECTIVE: To identify developmental features, the presence of hereditary burden, social adaptation, the structure of early psychopathological disorders in pediatric patients with schizotypal disorder (STD) and their relationship with the age of manifestation and the clinical structure of the disease. MATERIAL AND METHODS: The study included 150 patients aged 7 to 16 years with a diagnosis of SD, of which 48 were female and 102 were male. Based on the age of onset of the first stable psychopathological disorders, at the stage preceding the diagnosis of SD, 5 groups of patients were identified: up to 3 years (n=38), from 4 to 6 years (n=36), from 7 to 10 years (n=15), 11-13 (n=41), 14-16 years old (n=20). The study used clinical-psychopathological, clinical-catamnestic, with a retrospective analysis, neurological, pathopsychological, psychometric and statistical research methods. RESULTS: A high frequency of deviations from normative parameters in early psychomotor development was found in 99 (65%) patients with STD. Mental retardation was observed in 23 (15%) patients, dissociation in mental development was detected in a significant number of patients - 62 (41%). At the same time, the most significantly more frequent and pronounced were violations in the two youngest groups with the onset of psychopathological disorders up to 6 years. In these groups, there was also more often a deficit in three areas at once - emotional, motivational and volitional (38%) compared with the 4th group (13%). In groups 1 and 2, a deficit in intellectual development was also characteristic, which was reflected in academic indicators. High performance in the primary grades was observed in 16% of patients in the 1st group versus 60% in the 5th, and poor performance was found in 37% in the 1st group and only 5% in the 5th. The relationship of clinical variants of STD with the selected groups was revealed. The diagnosis of schizotypal personality disorder was significantly more often (66%) diagnosed in patients from group 1 compared with groups 3 and 5. In group 2, this diagnosis was established in a third of cases. The diagnosis of the psychopathic variant of STD was predominant in patients with the onset of the disorder between 7 and 13 years of age. The neurosis-like variant had a clear tendency to become more frequent with older age, reaching statistically significant differences in group 5 compared to group 1. CONCLUSION: The age of onset and duration of persistence of psychopathological disorders determines the level of negative changes that have formed at the stage of the disease preceding the onset of distinct clinical symptoms of STD. Age at onset determines the predominant positive disorder.

Developmental profiles of schizotypy in the general population: A record linkage study of Australian children aged 11-12 years.

OBJECTIVES: The detection of young people at high risk for psychotic disorders has been somewhat narrowly focused on overt symptom-based markers that reflect mild reality distortion (e.g., psychotic-like experiences), or prodromal syndromes that are proximal to psychosis onset. The concept of schizotypy represents a broader framework for investigating risk for schizophrenia (and other disorders) in childhood, before the onset of prodromal or overt symptoms. We sought to detect profiles of risk for psychosis (schizotypy) in a general population sample of 22,137 Australian children aged 11-12 years, and to determine early life risk factors associated with these profiles from data available in linked records (registers). METHODS: Fifty-nine self-reported items were used as indicators of schizotypy across six broad domains; z-scores for each domain were subjected to latent profile analyses (LPA). A series of multinomial logistic regressions was used to examine the association between resulting profile (class) membership and several childhood and parental risk factors, and the proportion of children with mental disorders among each schizotypy profile was examined. RESULTS: The LPA revealed three person-centred profiles referred to as True Schizotypy (n = 1,323; 6.0%), Introverted Schizotypy (n = 4,473; 20.2%), and Affective Schizotypy (n = 4,261; 19.2%), as well as a group of children showing no risk (n = 12,080; 54.6%). Prior exposure to perinatal and familial adversities including childhood maltreatment, as well as poor early childhood development and academic functioning, was variously associated with all risk groups. There was a higher proportion of childhood mental disorder diagnoses among children in the True Schizotypy group, relative to other profiles. CONCLUSION: Subtle differences in the pattern of exposures and antecedents among schizophrenia liability profiles in childhood may reflect distinct pathogenic pathways to psychotic or other mental illness. PRACTITIONER POINTS: Children aged 11-12 years report characteristics of schizotypy which can be classified into three distinct profiles that may represent different pathological processes towards later mental ill-health. Early life exposure to perinatal and familial adversities including childhood maltreatment, early childhood developmental vulnerability, and poor academic functioning predict membership in all three childhood schizotypy profiles. Latent liability for schizophrenia (and potentially other mental disorders) may be represented by different profiles of functioning observable in childhood.

Emotion Regulation and Depressive Symptoms Mediate the Association Between Schizotypal Personality Traits and Suicidality in Chinese College Students.

OBJECTIVE: The psychological mechanisms underlying the relationship between schizotypal personality traits and suicidality are not understood. This study investigated the association of schizotypal personality traits with suicidality and explored the mediating role of cognitive appraisal and depression in the relationship between those two variables in a sample of Chinese college students. METHOD: Participants (N = 2457) completed the Schizotypal Personality Questionnaire, the Emotional Regulation Questionnaire, the Zung Self-rating Depression Scale, and three questions related to suicidality. RESULTS: The cognitive reappraisal score was lower in the students with suicidality than the students without suicidality, whereas scores for depression and schizotypal personality traits were higher in the students with suicidality than the students without suicidality. Schizotypal personality traits and depression were risk factors for suicidality. Depression mediated the association between schizotypal personality traits and suicidality. Cognitive reappraisal negatively affected symptoms of depression and had a significant mediating effect on the association between schizotypal personality traits and suicidality. CONCLUSIONS: Schizotypal personality traits and depression are risk factors for suicidality. Cognitive reappraisal and depression mediate the association between schizotypal personality traits and suicidality.

The prevalence, incidence, and admission rate of diagnosed schizophrenia spectrum disorders in Korea, 2008-2017: A nationwide population-based study using claims big data analysis.

This study estimated the prevalence and incidence rate of schizophrenia, schizotypal, and delusional disorders (SSDD) in Korea from 2008 to 2017 and analyzed the hospital admission rate, re-admission rate, and hospitalization period. It used the Korean nationwide National Health Insurance Service claims database. SSDD patients who had at least one visit to Korea's primary, secondary, or tertiary referral hospitals with a diagnosis of SSDD, according to the International Classification of Diseases, 10th Revision (ICD-10), were identified as SSDD cases if coded as F20-F29. Data were analyzed using frequency statistics. Results showed that the 12-month prevalence rate of SSDD increased steadily from 0.40% in 2008 to 0.45% in 2017. Analysis of the three-year cumulative prevalence rate of SSDD showed an increase from 0.51% in 2011 to 0.54% in 2017. In 2017, the five-year cumulative prevalence rate was 0.61%, and the 10-year cumulative prevalence rate was 0.75%. The hospital admission rate among SSDD patients decreased from 2008 (30.04%) to 2017 (28.53%). The incidence of SSDD was 0.05% and no yearly change was observed. The proportion of SSDD inpatients whose first hospital visit resulted in immediate hospitalization was 22.4% in 2017. Epidemiological indicators such as prevalence, incidence, and hospitalization rate play an important role in planning social and financial resource allocation. Therefore, efforts to produce more accurate epidemiological indicators are very important and this study's findings could have a significant social impact.

Adaptive and maladaptive features of schizotypy clusters in a community sample.

Schizotypal personality traits correlate with psychopathology and impaired functional outcome. Yet advantageous aspects of positive schizotypy may exist which could promote resilience and creativity, and several studies have identified a high positive but low negative schizotypy group with some signs of adaptation. The aim of our study was to clarify whether such individuals demonstrate only traits associated with well-being, or they also have traits that predict impairment. Participants (N = 643 students, 71.5% female) completed measures of schizotypy, resilience, self-esteem, self-concept clarity, and absorption. We identified four clusters: an overall low schizotypy, an overall high schizotypy, a disorganised-interpersonal schizotypy and a positive schizotypy cluster. The overall high schizotypy cluster seemed to be the most vulnerable as it was the least resilient and showed widespread maladaptation, whereas the high positive schizotypy cluster had intact self-esteem and high resilience and its elevated absorption may hold the promise for adaptive outcomes such as creativity and positive spirituality. However, the high positive schizotypy cluster lacked self-concept clarity. The results suggest that individuals showing high positive and low negative schizotypy demonstrate features promoting mental well-being to an extent that is higher than in all the other clusters, while their self-concept impairment is similar to that observed in the high and the disorganised-interpersonal schizotypy clusters. Better understanding of these factors could be informative for prevention and treatment of psychosis-spectrum disorders.

Association between traumatic stressful events and schizotypal symptoms among a community-based sample of adolescents: A 2-year longitudinal study.

BACKGROUND: Traumatic stressful events (TSEs) are among the most studied risk factors for subsequent schizotypal symptoms. However, specificity and aggregate effects of trauma exposure on schizotypal symptoms remain unclear. This study investigates these relationships among a community-based sample of US adolescents. MATERIAL AND METHODS: A sub-sample of 426 adolescents (51.6% female) from the Philadelphia Neurodevelopmental Cohort study were selected for longitudinal follow-up based on presence (n = 209) or absence (n = 217) of psychosis spectrum symptoms (PSS). At baseline, they completed assessments of demographic, TSEs, other psychopathology (e.g., PSS, anxiety, depression, and behavioral disorder) and family history of psychopathology. Schizotypal symptom dimensions (cognitive-perceptual, interpersonal and disorganized) were evaluated approximately two years later. RESULTS: More than half of adolescents experienced at least one type of TSE. Adolescents with assaultive trauma reported about 1.5 times as many symptoms on all three schizotypal symptom dimensions, compared to adolescents with non-assaultive TSE, adjusting for demographic and family history variables. No statistical significance was found after further adjusting for other baseline psychopathology (p > 0.05). There was a significant aggregate effect of TSEs on cognitive-perceptual symptoms with small effect size (p < 0.001, Cohen's f2 = 0.034). CONCLUSIONS: We found evidence of an association between aggregate TSEs and cognitive-perceptual symptoms, but trauma type was not associated with schizotypal symptom dimensions when controlling for potential confounders. Our findings highlight the importance of considering aggregate TSE effects and potential confounds when examining associations between TSEs and schizotypy. Trauma and psychosis spectrum screening may be important in the effort to provide trauma-informed care.

Schizotypal personality disorder and suicide: problems and perspectives.

Schizotypal personality disorder (SPD) is classified in DSM-V as a cluster A personality disorder. Cluster A personality disorders are described as odd or eccentric conditions. SPD is associated with significant disability and many psychiatric comorbidities. Several studies have shown that SPD and schizotypal traits are associated with suicidal ideation and behaviour. Suicide prevention interventions in individuals with SPD are impeded because (1) SPD is frequently not diagnosed; (2) SPD is difficult to treat; and (3) there are no guidelines for suicide screening or suicide prevention interventions in individuals with SPD. Suicide prevention in persons with SPD consists of (1) diagnosing SPD; (2) providing appropriate treatment for SPD; and (3) providing suicide screening and suicide prevention. Interventions aiming at reduction of depressive symptoms, improvement of self-esteem, and interpersonal skills may be effective at reducing suicide risk amongst individuals with SPD. Studies of suicidality in persons with SPD are needed and may be an important area of suicide research. It is to be hoped that future studies of the pathophysiology of suicidality in individuals with SPD will help to develop strategies for suicide screening and suicide prevention interventions in persons with SPD and improve suicide prevention in this challenging patient population.

Association between schizotypal personality traits and emotional instability: mediation and moderation analysis among Chinese college students.

BACKGROUND: Previous studies identified an association between schizophrenia and emotional instability. However, the relationship between schizotypal personality traits and emotional instability has not been explored to date. Furthermore, both mediating and moderating factors need to be identified. METHODS: A total of 2936 students completed the Schizotypal Personality Questionnaire (SPQ), the Affective Lability Scale-Short Form (ALS-SF), and the Davos Assessment of Cognitive Biases Scale (DACOBS). RESULTS: 1) The total scores of DACOBS (and all dimensions) and ALS-SF (and all dimensions) in the high schizotypal personality trait group were higher than in the low schizotypal personality trait group (all P < 0.05). 2) SPQ score and DACOBS social cognition problems, subjective cognitive problems, jumping to conclusions bias, and external attribution bias subscale scores positively predicted the total score of ALS-SF (or the dimensions of ALS-SF) in both male and female populations (all P < 0.05). 3) In the male population, DACOBS social cognition problems, subjective cognitive problems, jumping to conclusions bias, and external attribution bias subscale scores mediated the relationship between SPQ score and ALS-SF total score (or its subscales). In the female population, DACOBS attention for threat bias, external attribution bias, jumping to conclusions bias, social cognition problems, and subjective cognitive problems subscale scores mediated the relationship between SPQ score and ALS-SF total score (or its subscales). 4) Gender exerted a moderating effect on this relationship between SPQ score and ALS-SF total/anxiety-depression score (all P < 0.05). CONCLUSIONS: Schizotypal personality traits might influence emotional instability through cognitive biases, and the degree of this influence varies depending on gender.

Do schizotypy features predict cannabis problems in partnered community adults?

Schizotypy and its associated features-negative schizotypy, disorganization, and positive schizotypy-are correlated with increased cannabis use. Yet, it is unclear whether cannabis users with schizotypy are at greater risk of developing cannabis problems. Individuals with elevated schizotypy may be particularly vulnerable to cannabis problems. It is important to understand this association given the unknown harms of chronic cannabis use. Data for these analyses were drawn from a larger investigation of cannabis use in adult romantic relationships. Participants were community adults (N = 366; M Age = 24.6, SD = 3.1) who reported regular use of cannabis. Participants completed baseline surveys measuring cannabis use frequency, problems, and schizotypy. Follow-up assessments of cannabis problems and frequency were completed 4-, 7- and 10-months post-baseline. Multiple regression was used to test the effect of schizotypy-measured using the Schizotypal Personality Questionnaire-Brief (SPQ-B, Raine & Benishay, 1995)-on cannabis use problems controlling for 30-day cannabis use. At baseline, disorganization and positive schizotypy were associated with cannabis use, primarily for women. Results revealed that with cannabis use frequency in the model, the Disorganization subscale of the SPQ-B predicted cannabis problems at baseline and all 3 follow-up assessments. Results are consistent with research suggesting that those exhibiting odd behaviors report more problematic cannabis use. Future research may further this line of inquiry with a focus on longitudinal, reciprocal relationships among schizotypy features, cannabis use, and cannabis problems.

Early life factors of schizotypal personality disorder in adolescents: A systematic review.

WHAT IS KNOWN ON THE SUBJECT?: The complexity and high prevalence of schizotypal personality disorders (SPD) pose serious challenges for mental health practice in its management, and also bring severe consequences for the patients. The identification of the specific early life factors (ELFs) that confer risk to SPD has become a major focus of clinical research on schizophrenia-spectrum disorders which aligns well with the mental health nursing's responsibility in health promotion, prevention and treatment. WHAT THIS PAPER ADDS TO EXISTING KNOWLEDGE?: Adolescents may experience certain ELFs, which contribute to the occurrence of SPD, but no systematic review has been conducted to identify ELF among them. And nursing literature addressing modifiable ELF is very limited. Two clusters of ELF and SPD in adolescents were identified: prenatal and early postnatal factors; childhood trauma and parental factors. The findings also show that more research is needed to determine the specificity and cumulative effects of ELF on the development of SPD by using rigorous and comprehensive measurements and a longitudinal design. WHAT ARE THE IMPLICATIONS FOR PRACTICE?: Mental health nurses, especially nurses in the primary care, should be aware of potentially modifiable ELFs and incorporate more comprehensive and valid instrument for assessing cumulative ELF and SPD. These findings may serve to inform possible future interventions for SPD, such as parent education and support to mitigate these risk factors. ABSTRACT: INTRODUCTION: Schizotypal personality disorder (SPD) affects 4% of the general population in the United States. The identification of early life factors (ELFs) that confer risk to SPD in adolescents (ages 10-24 years old) has become a major focus of clinical research on schizophrenia-spectrum disorders. AIM: This systematic review aims to determine what ELFs contribute to the onset of SPD in the adolescent population. METHODS: A systematic search of PubMed, PsycINFO, Psychiatry online, Scopus, Web of Science, EMBASE and CINAHL databases was conducted using relevant keywords. Data were extracted using a standardized form following PRISMA guidelines. RESULTS: Twenty-four studies met the criteria for inclusion. ELFs in the development of SPD were grouped into two important clusters: (a) prenatal and early postnatal factors; (b) childhood trauma and parental factors. CONCLUSION: Mental health nurses, especially nurses in primary care, should be aware of potentially modifiable ELF. Longitudinal research is needed to determine the causative roles of these ELF play in the occurrence of SPD by using rigorous measurements. IMPLICATIONS FOR PRACTICE: These findings call for awareness of the modifiable ELF for SPD and also inform possible future interventions to reduce these risks, such as parent-training or environmental enrichment programmes.

Psychotic Experiences and Schizotypy in Early Adolescence Predict Subsequent Suicidal Ideation Trajectories and Suicide Attempt Outcomes From Age 18 to 38 Years.

Subclinical risk markers for schizophrenia predict suicidality, but little is known about the nature of the relationship. Suicidal ideation is often considered homogenous, but distinguishing passive from active ideation (ie, thoughts of death vs thoughts of killing oneself) and different temporal patterns may further the understanding of risk factors. We tested whether schizotypy and psychotic experiences (PEs) in early adolescence predict subsequent growth trajectories of suicidal ideation and suicide attempt outcomes. Participants were 1037 members of the population-representative Dunedin Study cohort. PE was measured at 11 years and schizotypy at 13 and 15 years. Outcomes were passive and active suicidal ideation, and suicide attempt, measured at 18, 21, 26, 32, and 38 years. Passive ideation was best represented by 2 trajectories, including persistent and transient ideation classes. Schizotypy predicted membership in the smaller persistent class (odds ratio [OR] = 1.21, P = .041), whereas PE was not associated with class membership. The probability of suicide attempts was 13.8% in the persistent ideation class, compared with 1.8% in the transient class. Active ideation was best represented by a 1-class model, the intercept of which was predicted by schizotypy (OR = 1.23, P = .015). Suicide attempts were predicted by schizotypy (OR = 1.53, P = .040) and PE (OR = 3.42, P = .046), and this was partially mediated by indirect effects via the active ideation trajectory. Findings indicate that adolescent schizotypy and PE are related to subsequent suicidal ideation and attempts. Suicidal ideation is heterogeneous, and schizotypy is specifically related to a persistent passive ideation subgroup.