The association between trauma and delusional-like experiences

Associations between social engagement, internalizing symptoms, and delusional ideation in the general population

BACKGROUND

Delusions are a hallmark feature of psychotic disorders and lead to significant clinical and functional impairment. Internalizing symptoms-such as symptoms of depression, anxiety, and trauma exposure-are commonly cited to be related to delusions and delusional ideation and are often associated with deficits in social functioning. While emerging studies are investigating the impact of low social engagement on psychotic-like experiences, little work has examined the relationship between social engagement, internalizing symptoms, and delusional ideation, specifically.

METHODS

Using general population data from the Nathan Kline Institute-Rockland (NKI-Rockland) database (N = 526), we examined the relationships between self-reported delusional ideation, internalizing symptoms, and social engagement and tested four indirect effect models to understand how these factors interrelate.

RESULTS

Delusional ideation was significantly associated with both increased internalizing symptoms (r = 0.41, p < 0.001) and lower social engagement (r = - 0.14, p = 0.001). Within aspects of social engagement, perceived emotional support showed the strongest relationship with delusional ideation (r = - 0.17, p < 0.001). Lower social engagement was also significantly associated with increased internalizing symptoms (r = - 0.29, p < 0.001). Cross-sectional models suggest that internalizing symptoms have a significant indirect effect on the association between delusional ideation and social engagement.

CONCLUSIONS

These findings reveal that elevated delusional ideation in the general population is associated with lower social engagement. Elevated internalizing symptoms appear to play a critical role in reducing engagement, possibly exacerbating delusional thinking. Future work should examine the causal and temporal relationships between these factors.

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.

Humiliation and state anxiety as predictors of attenuated psychosis in a community sample

Existing literature suggests that humiliation experiences, coupled with a negative family context, significantly predicts persecutory ideation in non-clinical participants. Whether this may also be linked to attenuated psychotic experiences is unknown. The current study aimed to assess whether familial adversity and humiliation may be related to hallucination-like experiences (HLEs) and other psychotic symptoms, and if state anxiety significantly contributed to these relationships. This cross-sectional study recruited a community sample of 93 adults (38% male; mean age = 27.3 years, standard deviation = 10.8 years), who completed measures of maladaptive familial environments, past and anticipated humiliation experiences, state anxiety and attenuated psychotic symptoms. Correlations and hierarchical regressions tested for direct and indirect relationships amongst study variables. A maladaptive family context, and humiliation (past and anticipated) were positively correlated with HLEs, and facets of attenuated psychotic symptoms. Anxiety uniquely predicted audio-visual and multisensory HLEs. Past humiliation and anxiety jointly predicted cognitive-perceptual disturbance and disorganisation, whereas fear of humiliation and anxiety jointly predicted interpersonal difficulty. Elevated state anxiety, coupled with humiliation, may increase attenuated psychotic symptoms in adulthood. Future research is needed to ascertain if these relationships hold true in clinical cohorts to examine the clinical significance of these data.

The Indirect Effect of Trauma via Cognitive Biases and Self-Disturbances on Psychotic-Like Experiences

Although self-disturbances (SD) are considered to be a core psychopathological feature of schizophrenia spectrum disorders, there is still insufficient empirical data on the mechanisms underlying these anomalous self-experiences. The aim of the present study was to test a hypothesized model in which cognitive biases and exposure to traumatic life events are related to the frequency of SD which, in turn, contribute to the frequency of psychotic-like experiences (PLEs). Our sample consisted of 193 Polish young adults from the general population (111 females; 18-35 years of age, M = 25.36, SD = 4.69) who experience frequent PLEs. Participants were interviewed for PLEs, SD and social functioning as well as completed self-reported questionnaires and behavioral tasks that measure cognitive biases (e.g., safety behaviors, attention to threat, external attribution, jumping to conclusion, source monitoring, overperceptualization). The model was tested using path analysis with structural equation modeling. All of the hypothesized relationships were statistically significant and our model fit the data well [χ²(23) = 31.201; p = 0.118; RMSEA = 0.043 (90% CI = 0.00-0.078), CFI = 0.985, SRMR = 0.041, TLI = 0.976]. The results revealed a significant indirect effect of traumatic life events on PLEs through SD and self-reported cognitive biases. However, performance-based cognitive biases measured with three behavioral tasks were unrelated to SD and PLEs. The frequency of SD explained a substantial part (43.1%) of the variance in PLEs. Further studies with longitudinal designs and clinical samples are required to verify the predictive value of the model.

How Mental Health Professionals Can Address Disparities in the Context of the COVID-19 Pandemic

The Coronavirus 2019 (COVID-19) pandemic is an unparalleled crisis, yet also a unique opportunity for mental health professionals to address and prioritize mental and physical health disparities that disproportionately impact marginalized populations. Black, Indigenous, and People of Color (BIPOC) have long experienced structural racism and oppression, resulting in disproportionately high rates of trauma, poverty, and chronic diseases that span generations and are associated with increased COVID-19 morbidity and mortality rates. The current pandemic, with the potential of conferring new trauma exposure, interacts with and exacerbates existing disparities. To assist mental health professionals in offering more comprehensive services and programs for those who have minimal resources and the most profound barriers to care, four critical areas are highlighted as being historically problematic and essential to address: (a) recognizing psychology's role in institutionalizing disparities; (b) examining race/ethnicity as a critical variable; (c) proactively tackling growing mental health problems amidst the COVID-19 crisis; and (d) understanding the importance of incorporating historical trauma and discrimination in research and practice. Recommendations are provided to promote equity at the structural (e.g., nationwide, federal), professional (e.g., the mental health professions), and individual (e.g., practitioners, researchers) levels.

Physical injury and psychotic experiences in 48 low- and middle-income countries

BACKGROUND

Psychotic experiences (PEs) may be associated with injuries, but studies focusing specifically on low- and middle-income countries (LAMICs) are scarce. Thus, the current study examined the link between injuries and PEs in a large number of LAMICs.

METHOD

Cross-sectional data were used from 242 952 individuals in 48 LAMICs that were collected during the World Health Survey in 2002-2004 to examine the association between traffic-related and other (non-traffic-related) forms of injury and PEs. Multivariable logistic regression analysis and meta-analysis were used to examine associations while controlling for a variety of covariates including depression.

RESULTS

In fully adjusted analyses, any injury [odds ratio (OR) 2.07, 95% confidence interval (CI) 1.85-2.31], traffic injury (OR 1.84, 95% CI 1.53-2.21) and other injury (OR 2.09, 95% CI 1.84-2.37) were associated with higher odds for PEs. Results from a country-wise analysis showed that any injury was associated with significantly increased odds for PEs in 39 countries with the overall pooled OR estimated by meta-analysis being 2.46 (95% CI 2.22-2.74) with a moderate level of between-country heterogeneity (I2 = 56.3%). Similar results were observed across all country income levels (low, lower-middle and upper-middle).

CONCLUSIONS

Different types of injury are associated with PEs in LAMICs. Improving mental health systems and trauma capacity in LAMICs may be important for preventing injury-related negative mental health outcomes.

Specificity of Childhood Trauma Type and Attenuated Positive Symptoms in a Non-Clinical Sample

BACKGROUND

Childhood traumatic experiences have been consistently associated with psychosis risk; however, the specificity of childhood trauma type to interview-based attenuated positive psychotic symptoms has not been adequately explored. Further, previous studies examining specificity of trauma to specific positive symptoms have not accounted for co-occurring trauma types, despite evidence of multiple victimization.

METHODS

We examined the relationship between childhood trauma (Childhood Trauma Questionnaire) with type of attenuated positive symptom, as measured by the Structured Interview for Psychosis-risk Syndromes (SIPS) among a non-clinical, young adult sample (n = 130). Linear regressions were conducted to predict each attenuated positive symptom, with all trauma types entered into the model to control for co-occurring traumas.

RESULTS

Results indicated that childhood sexual abuse was significantly associated with disorganized communication and childhood emotional neglect was significantly associated with increased suspiciousness/persecutory ideas, above and beyond the effect of other co-occurring traumas. These relationships were significant even after removing individuals at clinical high-risk (CHR) for psychosis (n = 14).

CONCLUSIONS

Our results suggest that there are differential influences of trauma type on specific positive symptom domains, even in a non-clinical sample. Our results also confirm the importance of controlling for co-occurring trauma types, as results differ when not controlling for multiple traumas.

Why are psychotic experiences associated with self-injurious thoughts and behaviours? A systematic review and critical appraisal of potential confounding and mediating factors

Psychotic experiences (PEs), including hallucination- and delusion-like experiences, are robustly associated with self-injurious thoughts and behaviours (SITB) in the general population. However, it remains unclear as to why there is an association. The purpose of this systematic review was to elucidate the role of other factors that influence the association between PEs and SITB and, in doing so, highlight potential mechanisms underlying the relationship. A search of electronic international databases was undertaken, including PubMed, PsycINFO and EMBASE, and eligible studies were grouped according to seven confounder categories: sociodemographics, mental disorders, alcohol and substance use, environmental, psychological, intervention and family history/genetic factors. The systematic search strategy identified 41 publications reporting on 1 39 427 participants from 16 different countries. In the majority of studies, where adjustment for other variables occurred, the association between PEs and SITB persisted, suggesting PEs have an independent role. Common mental disorders, psychological distress and negative environmental exposures explained a substantial amount of the variance and therefore need to be considered as potential underlying mechanisms. There was high variability in the variables adjusted for in these studies, and so the question still remains as to whether the association between PEs and self-harm/suicidality can be attributed (fully or in part) to confounding and mediating factors or directly causal mechanisms. Regardless of causality, the now extensive literature reporting an association between these two clinical phenomena supports the broad usefulness of PEs as an indicator of risk for SITB.

Are Psychotic Experiences Related to Poorer Reflective Reasoning?

Background: Cognitive biases play an important role in the formation and maintenance of delusions. These biases are indicators of a weak reflective mind, or reduced engaging in reflective and deliberate reasoning. In three experiments, we tested whether a bias to accept non-sense statements as profound, treat metaphorical statements as literal, and suppress intuitive responses is related to psychotic-like experiences.

Methods: We tested deliberate reasoning and psychotic-like experiences in the general population and in patients with a former psychotic episode. Deliberate reasoning was assessed with the bullshit receptivity scale, the ontological confabulation scale and the cognitive reflection test (CRT). We also measured algorithmic performance with the Berlin numeracy test and the wordsum test. Psychotic-like experiences were measured with the Community Assessment of Psychic Experience (CAPE-42) scale.

Results: Psychotic-like experiences were positively correlated with a larger receptivity toward bullshit, more ontological confabulations, and also a lower score on the CRT but not with algorithmic task performance. In the patient group higher psychotic-like experiences significantly correlated with higher bullshit receptivity.

Conclusion: Reduced deliberate reasoning may contribute to the formation of delusions, and be a general thinking bias largely independent of a person's general intelligence. Acceptance of bullshit may be facilitated the more positive symptoms a patient has, contributing to the maintenance of the delusions.

Trauma and psychotic experiences: transnational data from the World Mental Health Survey

BackgroundTraumatic events are associated with increased risk of psychotic experiences, but it is unclear whether this association is explained by mental disorders prior to psychotic experience onset.AimsTo investigate the associations between traumatic events and subsequent psychotic experience onset after adjusting for post-traumatic stress disorder and other mental disorders.MethodWe assessed 29 traumatic event types and psychotic experiences from the World Mental Health surveys and examined the associations of traumatic events with subsequent psychotic experience onset with and without adjustments for mental disorders.ResultsRespondents with any traumatic events had three times the odds of other respondents of subsequently developing psychotic experiences (OR = 3.1, 95% CI 2.7-3.7), with variability in strength of association across traumatic event types. These associations persisted after adjustment for mental disorders.ConclusionsExposure to traumatic events predicts subsequent onset of psychotic experiences even after adjusting for comorbid mental disorders.

Dopamine, cognitive biases and assessment of certainty: A neurocognitive model of delusions

This paper examines the evidence that delusions can be explained within the framework of a neurocognitive model of how the brain assesses certainty. Here, 'certainty' refers to both low-level interpretations of one's environment and high-level (conscious) appraisals of one's beliefs and experiences. A model is proposed explaining how the brain systems responsible for assigning certainty might dysfunction, contributing to the cause and maintenance of delusional beliefs. It is suggested that delusions arise through a combination of perturbed striatal dopamine and aberrant salience as well as cognitive biases such as the tendency to jump to conclusions (JTC) and hypersalience of evidence-hypothesis matches. The role of emotion, stress, trauma and sociocultural factors in forming and modifying delusions is also considered. Understanding the mechanisms involved in forming and maintaining delusions has important clinical implications, as interventions that improve cognitive flexibility (e.g. cognitive remediation therapy and mindfulness training) could potentially attenuate neurocognitive processes.

Psychotic experiences in the population: Association with functioning and mental distress

Psychotic experiences are far more common in the population than psychotic disorder. They are associated with a number of adverse outcomes but there has been little research on associations with functioning and distress. We wished to investigate functioning and distress in a community sample of adolescents with psychotic experiences. Two hundred and twelve school-going adolescents were assessed for psychotic experiences, mental distress associated with these experiences, global (social/occupational) functioning on the Children's Global Assessment Scale, and a number of candidate mediator variables, including psychopathology, suicidality, trauma (physical and sexual abuse and exposure to domestic violence) and neurocognitive functioning. Seventy five percent of participants who reported psychotic experiences reported that they found these experiences distressing (mean score for severity of distress was 6.9 out of maximum 10). Participants who reported psychotic experiences had poorer functioning than participants who did not report psychotic experiences (respective means: 68.6, 81.9; OR=0.25, 95% CI=0.14-0.44). Similarly, participants with an Axis-1 psychiatric disorder who reported psychotic experiences had poorer functioning than participants with a disorder who did not report psychotic experiences (respective means: 61.8, 74.5; OR=0.28, 95% CI=0.12-0.63). Candidate mediator variables explained some but not all of the relationship between psychotic experiences and functioning (OR=0.48, 95% CI=0.22-1.05, P<0.07). Young people with psychotic experiences have poorer global functioning than those who do not, even when compared with other young people with psychopathology (but who do not report psychotic experiences). A disclosure of psychotic experiences should alert treating clinicians that the individual may have significantly more functional disability than suggested by the psychopathological diagnosis alone.

Adverse childhood events and psychosis in bipolar affective disorder

BACKGROUND

There has been increasing interest in the association between childhood trauma and psychosis. Proposals for potential mechanisms involved include affective dysregulation and cognitive appraisals of threat.

AIMS

To establish if, within bipolar disorder, childhood events show a significant association with psychosis, and in particular with symptoms driven by dysregulation of mood or with a persecutory content.

METHOD

Data on lifetime-ever presence of psychotic symptoms were determined by detailed structured interview with case-note review (n = 2019). Childhood events were recorded using a self-report questionnaire and case-note information.

RESULTS

There was no relationship between childhood events, or childhood abuse, and psychosis per se. Childhood events were not associated with an increased risk of persecutory or other delusions. Significant associations were found between childhood abuse and auditory hallucinations, strongest between sexual abuse and mood congruent or abusive voices. These relationships remain significant even after controlling for lifetime-ever cannabis misuse.

CONCLUSIONS

Within affective disorder, the relationship between childhood events and psychosis appears to be relatively symptom-specific. It is possible that the pathways leading to psychotic symptoms differ, with delusions and non-hallucinatory symptoms being influenced less by childhood or early environmental experience.

Psychotic experiences as a predictor of the natural course of suicidal ideation: a Swedish cohort study

Psychotic experiences are far more prevalent in the population than psychotic disorders and are associated with a wide range of depressive, anxiety and behavioral disorders, as well as increased risk for psychotic disorder. Recently, psychotic experiences have been highlighted as a potentially valuable clinical marker of risk for suicidal behavior. There have been few studies to date, however, to assess psychotic experiences as a predictor of suicidality over time. We wished to assess whether young persons with suicidal ideation at baseline assessment who reported psychotic experiences were at higher risk for persistence of suicidal ideation at follow-up than young persons who also reported suicidal ideation at baseline but who did not report co-occurring psychotic experiences. A total of 2,263 adolescents were assessed at age 13 to 14 years for psychotic experiences, suicidal ideation and internalizing and externalizing psychopathology. Participants were re-assessed at ages 16 to 17 years and 19 to 20 years. Among 13- to 14-year olds with suicidal ideation, co-occurring psychotic experiences did not predict an increased odds of persistence of suicidal ideation to age 16 to 17 years (OR=0.94, 95% CI: 0.19-4.78). Among 16- to 17-year olds with suicidal ideation, however, co-occurring psychotic experiences predicted a 6-fold increased odds of persistence of suicidal ideation to age 19 to 20 years (OR=5.53, 95% CI: 1.33-23.00). Psychotic experiences are an important but under-recognized marker of risk for persistence of suicidal ideation, in particular from mid-adolescence. An increased emphasis on the clinical assessment of psychotic experiences in mental health services should be a priority.

Stress and neurodevelopmental processes in the emergence of psychosis

The notion that stress plays a role in the etiology of psychotic disorders, especially schizophrenia, is longstanding. However, it is only in recent years that the potential neural mechanisms mediating this effect have come into sharper focus. The introduction of more sophisticated models of the interplay between psychosocial factors and brain function has expanded our opportunities for conceptualizing more detailed psychobiological models of stress in psychosis. Further, scientific advances in our understanding of adolescent brain development have shed light on a pivotal question that has challenged researchers; namely, why the first episode of psychosis typically occurs in late adolescence/young adulthood. In this paper, we begin by reviewing the evidence supporting associations between psychosocial stress and psychosis in diagnosed patients as well as individuals at clinical high risk for psychosis. We then discuss biological stress systems and examine changes that precede and follow psychosis onset. Next, research findings on structural and functional brain characteristics associated with psychosis are presented; these findings suggest that normal adolescent neuromaturational processes may go awry, thereby setting the stage for the emergence of psychotic syndromes. Finally, a model of neural mechanisms underlying the pathogenesis of psychosis is presented and directions for future research strategies are explored.

Association between traumatic experiences and psychosis among incarcerated men

The possible influence of traumatic experiences on subsequent manifestations of psychosis has been the subject of intense scientific debate in the last decade. Whereas some authors have found a clear association between trauma and psychosis, others have pointed out methodological deficiencies in the research or have found only weak associations. Others found no association between trauma and psychosis in exclusive samples of men and recommend the use of studies stratified by sex. This article uses the data from an epidemiological study of a random sample of 500 male inmates in two prisons in Andalusia (Spain) to analyze the association between psychosis and trauma. The inmates were diagnosed using The Structured Clinical Interview for DSM-IV Axis I Disorders (SCID-I) interviews by teams of experienced clinicians. The results show a clear association between traumatic events and some functional psychosis or some psychosis, including induced psychoses. These associations resist the possible effect of confusing variables such as the origin of the inmates, educational level, or having an addictive disorder. We discuss the need to pay special attention to traumatic experiences such as witnessing extreme violence against others or participating in acts of violence, particularly in men. Our results are compatible with different theories that defend the association between trauma and psychosis.

Service use for mental health problems in people with delusional-like experiences: a nationwide population based survey

Objective

Previous population-based studies have found that delusional-like experiences (DLEs) are prevalent in the community, and are associated with a wide range of mental health disorders. The aim of the study was to investigate mental health service use by people with DLEs.

Methods

Subjects were drawn from the Australian National Survey of Mental Health and Wellbeing 2007 of 8 841community residents aged between 16 and 85 years. The Composite International Diagnostic Interview (CIDI) was used to identify DLEs. Service utilization was assessed using a module that elicited information about hospital admissions, consultations with various health professionals, and prescription medication use. This study focussed on service use for mental health problems. We used logistic regression to examine the association, adjusting for potential confounding factors.

Results

Of 8 773 included participants, 8.4% (n = 776) positively endorsed one or more DLEs. With respect to consultations for mental health needs, individuals who endorsed DLEs were more likely to consult health professionals compared with those who did not endorse DLEs. Individuals with DLEs were also more likely to use prescription medicine. When we repeated the main analysis in a subgroup excluding any CIDI diagnosis of mental health disorders the results remained largely unchanged.

Conclusions

DLEs are common in the general population, and individuals with DLEs have an increased rate of accessing services for their mental health needs. Individuals endorsing both DLEs and increased help-seeking may identify a group of vulnerable people who have increased risk of developing psychotic illnesses later in life. This needs closer scrutiny in longitudinal prospective studies.

The heritability of delusional-like experiences

OBJECTIVE

Delusional-like experiences (DLE) are common in the general community and are associated with a family history of mental illness. The aim of this study was to estimate the heritability of DLE.

METHOD

The Peter's Delusional Inventory (PDI) was administered to a population-based cohort of mothers (n = 2861, aged 35-67 years) and their adult offspring (n = 3079, aged 18-23 years). Heritability of DLE was estimated from the sum scores of the 21 item PDI under the assumption that the covariance between mother-offspring scores is attributable to shared additive genetic factors.

RESULTS

The means (medians and standard deviations) for the total PDI scores for the mothers and their offspring were 3.6 (3.0, 3.0) and 5.0 (4.0, 3.5), respectively. The Pearson correlation coefficient between mother and offspring PDI scores was 0.17 (P < 0.001). The heritability was estimated to be 0.35 (standard error 0.04).

CONCLUSION

Heritable factors contribute to over a third of the variance of PDI scores in this population. In light of the association between a family history of a wide range of mental disorders and DLE, these experiences may represent a useful quantitative endophenotype for genetic studies of common mental disorders in population settings.

[Trauma and psychosis--part 2. On the association of early childhood maltreatment and risk of psychosis in general population]

Any association of early childhood maltreatment and later risk of psychosis may be favourably investigated by epidemiological studies in the general population. Primary outcome variable in these studies is the prevalence of subclinical psychotic symptoms (hallucinations, delusions) in early trauma-exposed groups compared to control groups without any significant trauma in childhood. A systematic literature search underlines a significant association of early childhood trauma and later non-clinical psychotic symptoms in representative samples of the general population both during childhood, adolescence and adulthood. Important questions deal with the issues, which psychological, psychosocial and neurobiological mechanisms may mediate the risk of early trauma in respect of later psychotic symptoms on the one side, and which factors may determine the transition from non-clinical psychotic symptoms to major psychotic disorders cared for within mental health services. Both theoretical models and first data derived from empirical studies will be presented.

The neurodevelopmental hypothesis of schizophrenia: convergent clues from epidemiology and neuropathology

The neurodevelopmental hypothesis of schizophrenia suggests that the disruption of early brain development increases the risk of later developing schizophrenia. This hypothesis focuses attention on critical periods of early brain development. From an epidemiologic perspective, various prenatal and perinatal risk factors have been linked to schizophrenia, including exposures related to infection, nutrition, and obstetric complications. From a genetic perspective, candidate genes have also been linked to altered brain development. In recent decades evidence from neuropathology has provided support for the neurodevelopmental hypothesis. Animal models involving early life exposures have been linked to changes in these same brain systems, providing convergent evidence for this long-standing hypothesis.

Social support and delusional-like experiences: a nationwide population-based study

BACKGROUND

Population-based studies have identified that delusional-like experiences (DLEs) are common in the general population. While there is a large literature exploring the relationship between poor social support and risk of mental illness, there is a lack of empirical data examining the association of poor social support and DLEs. The aim of the study was to explore the association between social support and DLEs using a large, nationally representative community sample.

METHODS

Subjects were drawn from a national multistage probability survey of 8841 adults aged between 16 and 85 years. The Composite International Diagnostic Interview was used to identify DLEs, common psychiatric disorders and physical disorders. Eight questions assessed various aspects of social support with spouse/partners and other family and friends. We examined the relationship between DLEs and social support using logistic regression, adjusting for potential confounding factors.

RESULTS

Of the sample, 8.4% (n = 776) positively endorsed one or more DLEs. Individuals who (a) had the least contact with friends, or (b) could not rely on or confide in spouse/partner, family or friends were significantly more likely to endorse DLEs. The associations remained significant after adjusting for a range of potential confounding factors.

CONCLUSIONS

DLEs are associated with impoverished social support in the general population. While we cannot exclude the possibility that the presence of isolated DLEs results in a reduction of social support, we speculate that poor social support may contribute in a causal fashion to the risk of DLEs.

Anxiety and depressive disorders are associated with delusional-like experiences: a replication study based on a National Survey of Mental Health and Wellbeing

OBJECTIVES

There is growing evidence that delusional-like experiences (DLE) are associated with common mental disorders. In particular, a National Mental Health Survey conducted in Australia during 2007 reported an association between DLE and both anxiety disorder and major depressive disorder (MDD). However, the previous study did not examine this association with respect to subtypes of anxiety disorder nor with severity of MDD. The aim of this study was to examine the associations between DLE and both anxiety disorder and MDD in more detail based on an independent population sample.

DESIGN

Cross-sectional study.

SETTING

Subjects were drawn from the Australian Survey of Mental Health and Wellbeing 1997 using a stratified multistage area sampling of persons living in private dwellings in all States and Territories of Australia.

PARTICIPANTS

Approximately 13 600 private dwellings were initially selected with one person aged 18 years or older from each dwelling invited to participate. In total, 10 641 individuals participated in the survey.

PRIMARY AND SECONDARY OUTCOME MEASURES

The Composite International Diagnostic Interview was used to identify individuals with DLE and Diagnostic and Statistical Manual of Mental Disorder, Fourth Edition (DSM IV) lifetime diagnoses of anxiety disorders and MDD. The influence of various anxiety disorders and MDD on DLE was assessed with logistic regression.

RESULTS

Having a lifetime diagnosis of either any anxiety disorder or MDD was significantly associated with the endorsement of DLE. The association was found for each of the main anxiety disorders when examined separately. There was a dose-response relationship between increasing severity of MDD and higher odds of DLE endorsement.

CONCLUSIONS

DLE are associated with a wide range of anxiety disorders and are more prevalent in those with MDD. Understanding the relationship between DLE, anxiety disorders and depression may provide insights into shared pathways that underpin both psychotic disorders and common mental disorders.

The association between delusional-like experiences, and tobacco, alcohol or cannabis use: a nationwide population-based survey

BACKGROUND

Previous population-based studies have found that delusional-like experiences (DLE) are prevalent in the community, and are associated with a wide range of mental health disorders including substance use. The aim of the study was to explore the association between DLE and three commonly used substances--tobacco, alcohol and cannabis.

METHODS

Subjects were drawn from the Australian National Survey of Mental Health and Wellbeing 2007. The Composite International Diagnostic Interview was used to identify DLE, common psychiatric disorders, and substance use. We examined the relationship between the variables of interest using logistic regression, adjusting for potential confounding factors.

RESULTS

Of 8,773 participants, 8.4% (n=776) subjects endorsed one or more DLE. With respect to tobacco use, compared to nonusers, DLE were more common in those who (a) had daily use, (b) commenced usage aged 15 years or less, and (c) those who smoked heavily (23 or more cigarettes per day). Participants with cannabis use disorders were more likely to endorse DLE; this association was most prominent in those with an onset of 16 years or younger. In contrast, the pattern of association between DLE versus alcohol use or dependence was less consistent, however those with early onset alcohol use disorders were more likely to endorse DLE probe items.

CONCLUSIONS

While cannabis use disorders have been previously linked with DLE, our findings linking alcohol and tobacco use and DLE suggest that the influence of these substances on psychosis-related outcomes warrants closer scrutiny in longitudinal prospective studies.

Socio-economic disadvantage and delusional-like experiences: a nationwide population-based study

PURPOSE

Delusional-like experiences (DLE) have been associated with low income, suggesting that more broadly defined socio-economic disadvantage may be associated with these experiences. We had the opportunity to explore the association between DLE and both individual- and area-level measures of socio-economic disadvantage.

METHOD

Subjects were drawn from the Australian National Survey of Mental Health and Wellbeing 2007. The Composite International Diagnostic Interview was used to identify DLE, common psychiatric disorders, and physical disorders. Individual-level and area-level socio-economic disadvantage measures were available based on variables including income, educational attainment, employment status, and housing. We examined the relationship between the variables of interest using logistic regression, adjusting for potential confounding factors.

RESULTS

Of the 8773 subjects, 8.4% (n=776) positively endorsed one or more DLE. DLE screen items were more likely to be endorsed by those who were (a) younger, (b) never married, or widowed, separated or divorced status, (c) migrants, or (d) living in rented houses. There were significant associations between socio-economic disadvantage and increased DLE endorsement, and this was found for both individual-level and area-level measures of socio-economic disadvantage. In general, the associations remained significant after adjusting for a range of potential confounding factors and in planned sensitivity analyses.

CONCLUSIONS

DLE are associated with socio-economic disadvantage in the general population. We speculate that the link between socio-economic disadvantage and DLE may be mediated by psychosocial stress and general psychological distress.

The association between delusional-like experiences and suicidal thoughts and behaviour

BACKGROUND

Delusional-like experiences (DLEs) are common in the general population. Whilst it is well known that psychotic disorders increase the risk of suicide, it is unclear if DLEs are also associated with suicidal thoughts and behaviour. This study aims to explore these variables in a large population-based sample.

METHOD

Participants were drawn from a national survey of mental health (n=8841) in Australia. The Composite International Diagnostic Interview was used to identify DLEs, psychiatric disorders, and information related to suicidal ideation, suicide plan and suicide attempts. We examined the relationship between DLEs and suicidal ideation, plans and attempts using logistic regression, adjusted for a range of potentially confounding variables.

RESULTS

8.4% of subjects endorsed one or more DLEs. 12.9% subjects reported suicidal ideation, 3.8% suicidal plans, and 3.0% a suicide attempt at some point in their lives. Those with any DLE were about two to four times as likely to report suicidal ideation, plans or attempts. There was a dose response relationship between DLEs and endorsement of suicide-related items.

CONCLUSIONS

DLEs are common in the general population and appear to be independently associated with suicidal thoughts and behaviour. DLE may provide a marker of vulnerability to suicide, and thus could be of value in future suicide prevention research.