Kim S. Betts

THE RELATIONSHIP BETWEEN MATERNAL DEPRESSIVE, ANXIOUS, AND STRESS SYMPTOMS DURING PREGNANCY AND ADULT OFFSPRING BEHAVIORAL AND EMOTIONAL PROBLEMS

Prenatal maternal depressive, anxious, and stress symptoms have been found to be associated with child and adolescent behavior problems. In this paper, we investigate their impact on behavior problems and depressive symptoms in adulthood.

Maternal depressive, anxious, and stress symptoms during pregnancy predict internalizing problems in adolescence.

Studies have shown a link between maternal–prenatal mental health and offspring behavior problems. In this paper, we derived longitudinal trajectories of maternal depressive, anxious, and stress symptoms over early life to predict offspring behavior in adolescence.

The role of sleep disturbance in the relationship between post-traumatic stress disorder and suicidal ideation

We tested if the risk of suicidal ideation in individuals with PTSD symptoms was dependent on comorbid sleep disturbance. Our cross-sectional sample included 2465 participants with complete data from the 21 year follow-up of the Mater University Study of Pregnancy (MUSP), a birth cohort study of young Australians. Using structural equation modelling with indirect pathways we found that 12 month PTSD symptoms did not directly predict suicidal ideation at 21 when adjusting for major depression symptoms, polyvictimization and gender. However, PTSD symptoms had an indirect effect on suicidal ideation via past-month sleep disturbance. Our results suggest that increased suicidal ideation in those with PTSD may result from the fact that PTSD sufferers often exhibit other comorbid psychiatric conditions which are themselves known to predict suicidal behaviours. Sleep disturbance may be targeted in those who experience PTSD to help prevent suicidal ideation.

The association between birth weight and anxiety disorders in young adults.

Recent evidence has linked birth weight to later behaviour/mental disorders, yet studies have hitherto neglected to investigate the relationship between birth weight and adult anxiety disorders. Prospectively collected data from 2210 mother/offspring pairs of the Mater University Study of Pregnancy (MUSP) birth cohort was used to test for associations between birth weight z-score and four major groupings of DSM-IV anxiety disorders. Birth weight z-score was linearly and inversely associated with lifetime diagnosis of post-traumatic stress disorders at 21 years, with those falling within the smallest birth weight quintile group at almost two-fold increased odds (OR=1.96, 95% CI: 1.10, 3.52) of being diagnosed with the disorder compared to those falling within the largest group. The association remained when subsequent analysis restricted the sample to those exposed to trauma. This is the first study in which birth weight has been found to be associated with post-traumatic stress disorders in adults.

Exploring the Female Specific Risk to Partial and Full PTSD Following Physical Assault

Previous studies have shown that females are at an increased risk of developing posttraumatic stress disorder (PTSD) in response to physical assault compared with males. Our aims were to (a) test if this gender-specific risk generalised to subclinical levels of PTSD, (b) observe how this relationship was affected by including possible confounding factors, and (c) estimate how this trauma contributed to the overall prevalence of PTSD in females. Data came from an Australian birth cohort study (n = 2,547) based in Brisbane, Australia that commenced in 1981. Using ordinal logistic regression adjusted for a wide range of confounding factors, including polyvictimisation and internalising and externalising symptoms, we found females were at a significantly greater risk compared to males of developing either partial or full PTSD, odds ratio (OR) = 7.68; 95% confidence interval (CI) = [2.94, 20.08], as well as full PTSD only, OR = 9.23; 95% CI = [2.77, 30.79], following the experience of assaultive violence (p value for test of interaction = .004). In addition to the high prevalence of sexual assault (12.9%), attributable risk analysis suggested that due to the strong risk of PTSD in females exposed to physical assault, physical assault is possibly a contributor to the overall female increased prevalence of PTSD.

Maternal prenatal infection, early susceptibility to illness and adult psychotic experiences: A birth cohort study

BACKGROUND Existing evidence has established that maternal infection during pregnancy and illness during early life are associated with later schizophrenia. No research has examined how the combination of these prenatal and postnatal exposures is linked to an increased risk to later schizophrenia and psychotic disorders. METHODS Participants from the Mater University Study of Pregnancy (MUSP), an Australian based, pre-birth cohort study were examined for lifetime DSM-IV positive psychotic experiences at 21 years by a semi-structured interview. Structural equation modelling was used to derive a general factor of psychotic experiences at age 21. Next, we undertook a number of separate analyses to investigate how prenatal infections and infant illness susceptibility are related to positive psychotic experiences in early adulthood, allowing for tests of moderation and mediation between the two risk factors. RESULTS After adjustment for important confounders, infant illness susceptibility was found to play a mediating role in the association between prenatal vaginal infection and later psychotic experiences. Whereby, infant illness susceptibility showed a direct association with psychotic experiences, while prenatal vaginal infection indirectly predicted psychotic experiences via infant illness susceptibility. CONCLUSION Our findings suggest that illness susceptibility in early infancy may be central to the relationship between prenatal vaginal infection and later psychotic experiences. Further research is needed to establish the mechanisms that link these prenatal and postnatal exposures with psychotic illness in later life.

Exposure to stressful life events during pregnancy predicts psychotic experiences via behaviour problems in childhood

BACKGROUND Exposure to stressful life events during pregnancy has been associated with later schizophrenia in offspring. We explore how prenatal stress and neurodevelopmental abnormalities in childhood associate to increase the risk of later psychotic experiences. METHODS Participants from the Mater University Study of Pregnancy (MUSP), an Australian based, pre-birth cohort study were examined for lifetime DSM-IV positive psychotic experiences at 21 years by a semi-structured interview (n = 2227). Structural equation modelling suggested psychotic experiences were best represented with a bifactor model including a general psychosis factor and two group factors. We tested for an association between prenatal stressful life events with the psychotic experiences, and examined for potential moderation and mediation by behaviour problems and cognitive ability in childhood. RESULTS Prenatal stressful life events predicted psychotic experiences indirectly via behaviour problems at child age five years, and this relationship was not confounded by maternal stressful life events at child age five. We found no statistical evidence for an interaction between prenatal stressful life events and behaviour problems or cognitive ability. CONCLUSION The measurable effect of prenatal stressful life events on later psychotic experiences in offspring manifested as behaviour problems by age 5. By identifying early abnormal behavioural development as an intermediary, this finding further confirms the role of prenatal stress to later psychotic disorders.

Hallucinations in adolescents and risk for mental disorders and suicidal behaviour in adulthood: Prospective evidence from the MUSP birth cohort study

BACKGROUND Hallucinations, once equated with serious mental disorders, are common in adolescents. Given the high prevalence of hallucinations, it is important to determine if they are associated with adverse mental health outcomes in adulthood. This study compared the mental health outcomes of participants (aged 30-33years) in the Mater-University of Queensland Study of Pregnancy (MUSP) who reported hallucinations at (a) 14years only and (b) 14 and 21years versus cohort members without hallucinations. METHOD Participants (n=333) were aged between 30 and 33years and (a) reported hallucinations on the Youth Self-Report Questionnaire at 14 and/or the Young Adult Self-Report Questionnaire at 21years and (b) controls (n=321) who did not report hallucinations. Lifetime diagnoses of mental disorders were ascertained by the Structured Clinical Interview for DSM Disorders (DSM IV-TR) administered by clinical psychologists. Suicidal behaviour was measured by self report. RESULTS Hallucinations at 14years only were not associated with an increased risk of mental disorders in adulthood. Hallucinations reported at both 14 and 21years were associated with lifetime diagnoses of psychotic disorders (OR, 8.84; 95% CI: 1.61-48.43 and substance use disorders (OR, 2.34; 95% CI: 1.36-4.07) and also strongly associated with lifetime suicide attempts (OR, 7.11; 95% CI: 2.68-18.83). CONCLUSIONS Most adolescents who experience hallucinations do not have an increased rate of mental disorder in adulthood; however, those with hallucinations that are experienced at more than one point in time are at increased risk of suicidal behaviour and both psychotic and non-psychotic psychopathology.

The association between lower birth weight and comorbid generalised anxiety and major depressive disorder.

OBJECTIVE Studies testing the association between birth weight and depression or anxiety have found inconsistent results and there has been a lack of research on the possible relationship between birth weight and comorbid anxiety and depression. We tested for an association between lower birth weight and major depression, generalised anxiety and comorbid generalised anxiety and major depression. METHOD Data was taken from 2113 mothers and their offspring participating in the Mater University Study of Pregnancy (MUSP) birth cohort. Generalised anxiety, major depression and comorbid generalised anxiety and major depression at 21 years were tested for associations with birth weight using multinomial logistic regression. RESULTS Lower birth weight was found to predict comorbid generalised anxiety and major depression, but did not predict either generalised anxiety or major depression. LIMITATIONS We were unable to specify comorbidity by the primary disorder, or by the severity or recurrence of the depression. CONCLUSION Previous associations found between birth weight and mental health may reflect a specific link between lower birth weight and comorbid generalised anxiety and major depressive disorders. As neither disorder individually was associated with lower birth weight, this may suggest that this developmental origin represents a unique risk pathway to comorbidity not shared with either discrete disorder.

Predictors of comorbid polysubstance use and mental health disorders in young adults-a latent class analysis

AIM The co-occurrence of mental health and substance use disorders adds complexity to already-significant health burdens. This study tests whether mental health disorders group differently across substance use disorder types and compares associations of early factors with the development of differing comorbidities. DESIGN Consecutive antenatal clinic attendees were recruited to the longitudinal Mater-University of Queensland Study of Pregnancy (MUSP). Mother/offspring dyads were followed over 21 years. SETTING Mater-Misericordiae Public Hospital, Brisbane, Australia. PARTICIPANTS MUSP offspring with maternal baseline information (n = 7223), offspring behaviour data at 14 (n = 4815) and psychiatric diagnoses at 21 (n = 2575). MEASUREMENTS The Composite International Diagnostic Interview yielded life-time diagnoses of mental health (MH) and substance use (SU) disorders for offspring, then latent class modelling predicted membership of polydisorder groups. We fitted the resulting estimates in multinomial logistic regression models, adjusting for maternal smoking, drinking and mental health, adolescent drinking, smoking and behaviour and mother-child closeness. FINDINGS Fit indices [Bayesian information criterion (BIC) = 12 415; Akaike information criterion (AIC) = 12 234] from LCA supported a four-class solution: low disorder (73.6%), MH/low SU disorder (10.6%), alcohol/cannabis/low MH disorder (12.2%) and poly SU/moderate MH disorder (3.5%). Adolescent drinking predicted poly SU/MH disorders [odds ratio (OR) = 3.34, 95% confidence interval (CI) = 1.42-7.84], while externalizing predicted membership of both SU disorder groups (ORalcohol/cannabis  = 2.04, 95% CI = 1.11-3.75; ORpolysubstance  = 2.65, 95% CI = 1.1-6.08). Maternal smoking during pregnancy predicted MH (OR = 1.53, 95% CI = 1.06-2.23) and alcohol/cannabis-use disorders (OR = 1.73; 95% CI = 1.22-2.45). Low maternal warmth predicted mental health disorders only (OR = 2.21, 95% CI = 1.32-3.71). CONCLUSIONS Mental health disorders are more likely in young adults with polysubstance use disorders than those with alcohol/cannabis use disorders. Predictors of comorbid mental health/polysubstance use disorders differ from those for alcohol/cannabis use disorders, and are detectable during adolescence.