The aetiology of psychosis high-risk mental states during adolescence in the ALSPAC cohort
Lead Research Organisation:
University of Bristol
Department Name: Community-Based Medicine
Abstract
The presence of psychotic symptoms such as delusions and hallucinations, along with impaired functioning is likely to present a high-risk mental state for development of clinically important psychotic disorders such as schizophrenia, and indeed such individuals are amongst the targets for early intervention services. Our broad aim is to understand more about how these high-risk mental states for psychosis arise during adolescence in order to inform future preventive interventions.
Our first two aims are to describe the extent of these high risk mental states and their relationship with earlier mental health problems, such as depression, anxiety, conduct problems as well as earlier psychotic symptoms. We will then look at two areas that appear to be very important for the aetiology of psychosis. The first of these is the consistent association found between people who have lower IQ scores and the development of psychosis. The second is the relationship between cannabis use and the later development of these high risk mental states. There is extensive and repeated data available on these matters in the Avon Longitudinal Study of Parents and Children (ALSPAC) and the study will be able to exploit the previously collected data in order to answer these questions.
Our first two aims are to describe the extent of these high risk mental states and their relationship with earlier mental health problems, such as depression, anxiety, conduct problems as well as earlier psychotic symptoms. We will then look at two areas that appear to be very important for the aetiology of psychosis. The first of these is the consistent association found between people who have lower IQ scores and the development of psychosis. The second is the relationship between cannabis use and the later development of these high risk mental states. There is extensive and repeated data available on these matters in the Avon Longitudinal Study of Parents and Children (ALSPAC) and the study will be able to exploit the previously collected data in order to answer these questions.
Technical Summary
The presence of psychotic symptoms with concurrent impaired functioning is likely to present a high-risk mental state for development of clinical psychotic disorders such as schizophrenia, and indeed such individuals are amongst the targets for early intervention services. Our broad aim is to understand more about how these high-risk mental states for psychosis arise during adolescence in order to inform future preventive interventions. More specifically our aims are as follows:
Aim 1: To estimate the prevalence of a high-risk mental state for psychosis at age 17, as defined by psychotic symptoms with concurrent impairment in social, educational, or occupational functioning.
Aim 2: To examine the continuities and discontinuities between psychopathology in childhood and early-mid adolescence and high-risk mental states at age 17.
Aim 3: To investigate the hypothesis that decline in IQ between 8 and 15 years is associated with the development of a high-risk mental state by age 17, independently of other psychopathology.
Aim 4: To investigate the hypothesis that cannabis use during adolescence is associated with development of a high-risk mental state by age 17, independently of confounding factors and reverse causation effects. We will also test the hypothesis that early use of cannabis confers an increased risk of a high risk mental state. We will examine gene-environment interplay between cannabis use and genetic variation within a number of candidate genes for psychosis including the reported interaction with variation within COMT.
In order to achieve these aims we will conduct an interview-based assessment of psychotic symptoms in a population-based sample of 17-year old adolescents within the ALSPAC cohort, and assess the impact of these symptoms on social, educational and occupational functioning from personal, parental and educational reports.
Aim 1: To estimate the prevalence of a high-risk mental state for psychosis at age 17, as defined by psychotic symptoms with concurrent impairment in social, educational, or occupational functioning.
Aim 2: To examine the continuities and discontinuities between psychopathology in childhood and early-mid adolescence and high-risk mental states at age 17.
Aim 3: To investigate the hypothesis that decline in IQ between 8 and 15 years is associated with the development of a high-risk mental state by age 17, independently of other psychopathology.
Aim 4: To investigate the hypothesis that cannabis use during adolescence is associated with development of a high-risk mental state by age 17, independently of confounding factors and reverse causation effects. We will also test the hypothesis that early use of cannabis confers an increased risk of a high risk mental state. We will examine gene-environment interplay between cannabis use and genetic variation within a number of candidate genes for psychosis including the reported interaction with variation within COMT.
In order to achieve these aims we will conduct an interview-based assessment of psychotic symptoms in a population-based sample of 17-year old adolescents within the ALSPAC cohort, and assess the impact of these symptoms on social, educational and occupational functioning from personal, parental and educational reports.
