Association of subclinical psychosis with suicidal ideation : A twin study

Subclinical psychosis, including schizotypal indicators and psychotic experiences, predicts future suicidal ideation. This relationship may reflect unmeasured confounding from environmental factors, genetic factors, or both. We used a genetically-informative twin design to understand if the association between subclinical psychosis and suicidal ideation is independent of shared genetic and environmental factors. We analysed cross-sectional associations of age-22 self-reported subclinical psychosis (positive, negative, and disorganised features) with suicidal ideation in twins participating in the FinnTwin12 study (maximum n = 1213). Then, we analysed the reverse association of age-14 suicidal ideation with age-22 subclinical psychosis. Associations were studied first among individuals and then within monozygotic (MZ) and dizygotic (DZ) pairs. Individual-level analyses showed that all subclinical psychosis factors were associated with suicidal ideation. In within-pair analyses, estimates of associations were lower for MZ pairs than DZ pairs, except for the negative schizotypy-suicidal ideation association where estimates were consistent across individual-level and within-pair analyses. Findings provide evidence that the association between negative features and suicide ideation is not explained by familial factors and may be causal, though the possibility of confounding by individual-specific environmental factors and reverse causation cannot be ruled out. The relationships of positive and disorganised subclinical psychosis features with suicidal ideation cannot be explained by confounding due to environmental factors shared between siblings, but their associations may be due to shared genetic factors. (C) 2020 Elsevier B.V. All rights reserved.Peer reviewe

Self-harm and suicidal ideation among young people is more often recorded by child protection than health services in an Australian population cohort

OBJECTIVE: We investigated patterns of service contact for self-harm and suicidal ideation recorded by a range of human service agencies - including health, police and child protection - with specific focus on overlap and sequences of contacts, age of first contact and demographic and intergenerational characteristics associated with different service responses to self-harm.METHODS: Participants were 91,597 adolescents for whom multi-agency linked data were available in a longitudinal study of a population cohort in New South Wales, Australia. Self-harm and suicide-related incidents from birth to 18 years of age were derived from emergency department, inpatient hospital admission, mental health ambulatory, child protection and police administrative records. Descriptive statistics and binomial logistic regression were used to examine patterns of service contacts.RESULTS: Child protection services recorded the largest proportion of youth with reported self-harm and suicidal ideation, in which the age of first contact for self-harm was younger relative to other incidents of self-harm recorded by other agencies. Nearly 40% of youth with a health service contact for self-harm also had contact with child protection and/or police services for self-harm. Girls were more likely to access health services for self-harm than boys, but not child protection or police services.CONCLUSION: Suicide prevention is not solely the responsibility of health services; police and child protection services also respond to a significant proportion of self-harm and suicide-related incidents. High rates of overlap among different services responding to self-harm suggest the need for cross-agency strategies to prevent suicide in young people.</p

Schizotypy and Suicidality: Exploring the Causal Influence of Schizophrenia Liability on Suicidal Ideation and Suicide Attempts

Suicide, suicide attempts, and suicide ideation account for a significant proportion of deaths, disability, and suffering worldwide. There is currently little knowledge about what factors causally influence risk for suicide. Schizotypy—a set of cognitive-perceptual, interpersonal, and disorganised indicators that reflect liability for schizophrenia—predicts concurrent and future suicidal ideation and attempts. Some suggest the schizotypy-suicidality relationship reflects the influence of shared risk factors, or that both are non-specific indicators of the severity of psychopathology. However, schizotypy is significantly related to suicidality after adjustment for confounding, suggesting an independent role. The overarching aim of the present thesis was to test whether schizotypy is causally related to suicidal ideation and attempts. In Studies 1 and 2, the causal relationship of schizotypy with suicidality was tested using Mendelian randomisation in two independent cohorts, the Philadelphia Neurodevelopmental Cohort (n = 4767) and the FinnTwin12 cohort (n = 1213). No associations were found between a schizophrenia polygenic risk score (PRS) and schizotypy, or between the schizophrenia PRS and suicidal ideation in either study. The schizophrenia PRS was associated with suicide attempts in the FinnTwin12 cohort. As the schizophrenia PRS was not validated as a proxy measure of schizotypy, causal inferences could not be clearly made. In Study 3, the causal relationship of schizotypy and suicidal ideation was examined with a co-twin control analysis in the FinnTwin12 cohort. Results were consistent with a causal relationship between interpersonal features of schizotypy and suicidal ideation. In contrast, there was no evidence cognitive-perceptual or disorganised features were causally related to suicidal ideation. Finally, in Study 4, to determine whether schizotypy was specifically related to certain subpopulations of suicide ideators (represented by distinct growth trajectories), growth mixture modelling was used to model suicidal ideation trajectories over a 20-year period in the Dunedin study cohort (n = 1037). Schizotypy predicted a persistent passive ideation trajectory more so than a transient ideation trajectory. Together, these results provide some evidence consistent with the view that schizotypy causally influences suicidality. However, some sources of confounding (e.g., by non-shared environmental variables) could not be controlled. Results were consistent with conceptualisations of schizotypy and suicidality as heterogenous constructs and provided preliminary evidence that the schizotypy-suicidality relationship may be stronger in certain subpopulations of suicidal ideators

Cumulative comorbidity between neurodevelopmental, internalising, and externalising disorders in childhood: a network approach

Cumulative comorbidity of mental disorders is common, but the extent and patterns of comorbid psychopathology in childhood are not well established. The current study aimed to elucidate the emergent patterns of cumulative mental disorder comorbidity in children using network analysis of diagnoses recorded between birth and age 12 years. Participants were 90,269 children (mean age 12.7 years; 51.8% male) within the New South Wales Child Development Study (NSW-CDS)-a longitudinal record-linkage cohort study of Australian children born in NSW between 2002 and 2005. Binary indicators for eight types of mental disorder were derived from administrative health records. Patterns of conditional association between mental disorders were assessed utilising network analysis. Of 90,269 children, 2268 (2.5%) had at least one mental disorder by age 12 years; of the 2268 children who had at least one mental disorder by age 12 years, 461 (20.3%) were diagnosed with two or more different disorders out of the eight disorder types included in analyses. All disorders were either directly or indirectly interconnected, with childhood affective and emotional disorders and developmental disorders being most central to the network overall. Mental disorder nodes aggregated weakly (modularity = 0.185) into two communities, representative of internalising and externalising disorders, and neurodevelopmental and sleep disorders. Considerable sex differences in the structure of the mental disorder comorbidity networks were also observed. Developmental and childhood affective and emotional disorders appear to be key to mental disorder comorbidity in childhood, potentially reflecting that these disorders share symptoms in common with many other disorders.</p

Early childhood developmental vulnerability associated with parental mental disorder comorbidity

OBJECTIVES: Parental mental health has a profound influence on the mental health and well-being of their offspring. With comorbid mental disorders generally the rule rather than the exception, increased knowledge of the impact of parental mental disorder comorbidity on early child development may facilitate improved targeting and delivery of early intervention for vulnerable offspring.METHODS: Participants were 66,154 children and their parents in the New South Wales Child Development Study - a prospective, longitudinal, record-linkage study of a population cohort of children born in NSW between 2002 and 2004. Early childhood developmental vulnerability was assessed at age ~5 years using the Australian Early Development Census, and information on parental mental disorders was obtained from administrative health records. Binomial and multinomial logistic regression were used to assess the relationship between parental mental disorders and early childhood developmental vulnerability on emotional and behavioural domains, as well as membership of latent developmental risk classes reflecting particular classes of vulnerability.RESULTS: Multiple diagnoses of mental disorders in mothers and fathers were associated with an increased likelihood of early childhood emotional and behavioural developmental vulnerability in offspring, relative to parents without mental disorder. The likelihood of offspring vulnerability increased with the number of parental comorbidities, particularly maternal comorbidities.CONCLUSION: Early childhood developmental vulnerability was strongly associated with parental mental ill-health, with the strength of associations increasing in line with a greater number of mental disorder diagnoses among mothers and fathers. New and expectant parents diagnosed with multiple mental disorders should be prioritised for intervention, including attention to the developmental well-being of their offspring.</p

Childhood Schizotypy and Adolescent Mental Disorder

BACKGROUND AND HYPOTHESIS: Schizotypy provides a framework for understanding the developmental nature of psychotic disorders and a means of identifying "at-risk" individuals early in the lifespan. However, there is a lack of prospective longitudinal research examining the relationship between schizotypy in childhood and later psychotic and other mental disorders. We hypothesized that distinct profiles of schizotypy in childhood would be differentially associated with psychotic and other mental disorders emerging later in adolescence.STUDY DESIGN: In a large population cohort of Australian young people (n = 26 837), we prospectively examined the relationship between person-centered profiles of schizotypy identified in middle childhood (age ~11 years) and adolescent diagnoses (age ~13-18 years) across 7 types of mental disorders using multinomial logistic regression.RESULTS: Membership in any of 3 childhood schizotypy profiles (true schizotypy, affective schizotypy, or introverted schizotypy) was associated with an increased likelihood of being diagnosed with any type of mental disorder in adolescence; effects were strongest for the true schizotypy group (aOR = 3.07, 95% CI = 2.64, 3.57), followed by the introverted (aOR = 1.94, 95% CI = 1.75, 2.15) and affective (aOR = 1.29, 95% CI = 1.13, 1.47) schizotypy groups. Six of the 7 types of mental disorders measured (including psychotic disorders) were associated with at least 1 schizotypy group.CONCLUSIONS: Schizotypy in middle childhood is an important correlate of mental disorders in adolescence; however, it does not appear to be specifically associated with psychotic disorders in this age group.</p

Cumulative environmental risk in early life is associated with mental disorders in childhood

BACKGROUND: No single environmental factor is a necessary or sufficient cause of mental disorder; multifactorial and transdiagnostic approaches are needed to understand the impact of the environment on the development of mental disorders across the life course.METHOD: Using linked multi-agency administrative data for 71 932 children from the New South Wales Child Developmental Study, using logistic regression, we examined associations between 16 environmental risk factors in early life (prenatal period to RESULTS: The ERS was associated with all types of mental disorder diagnoses in a dose-response fashion, such that 2.8% of children with no exposure to any of the environmental factors (ERS = 0), compared to 18.3% of children with an ERS of 8 or more indicating exposure to 8 or more environmental factors (ERS ⩾ 8), had been diagnosed with any type of mental disorder up to age 13-14 years. Thirteen of the 16 environmental factors measured (including prenatal factors, neighbourhood characteristics and more proximal experiences of trauma or neglect) were positively associated with at least one category of mental disorder.CONCLUSION: Exposure to cumulative environmental risk factors in early life is associated with an increased likelihood of presenting to health services in childhood for any kind of mental disorder. In many instances, these factors are preventable or capable of mitigation by appropriate public policy settings.</p

Parental and community risk factors for childhood self-harm thoughts and behaviours

BACKGROUND: Childhood self-harm is rare but increasing in frequency. Little is known about risk factors specifically for self-harm in preteen children.METHODS: We examined self-harm thoughts and behaviours in children aged 3-14 years in association with parental and community-level risk factors, using a large general population-based record linkage sample (n = 74,479).RESULTS: Parental factors were strongly associated with childhood self-harm, with over three-quarters of children with self-harm having a parent with a history of mental disorder and/or criminal offending. Community-level factors (socioeconomic deprivation, remote or regional location, and neighbourhood crime rate) were not associated with childhood self-harm after adjustment for confounding factors.LIMITATIONS: Measures of self-harm thoughts and behaviours derived from administrative data likely underestimate the prevalence of self-harm in the population.CONCLUSIONS: Intergenerational transmission of risk factors is likely an important contributor to childhood self-harm.</p