Childhood Predictors of Cluster A Personality Disorder Traits in Adolescence: A Seven-Wave Birth Cohort Study

Cluster A personality disorders are hypothesized to have their origins in childhood, but little prospective research exists to support this contention. We investigated whether factors intrinsic to the child, social-relational and environmental factors, and symptoms of other psychopathologies in childhood predict paranoid, schizoid, and schizotypal personality disorder traits at age 16. A sample from two birth cohorts in Trondheim, Norway (n = 1,077; 50.9% female) was examined biennially from age 4–16. Cluster A personality disorder traits were assessed with the Structured Clinical Interview for DSM-5 Personality Disorders and regressed on the intercept and growth in child risk and protective factors up to age 14. The prevalence of any Cluster A PD at age 16 was 2.41% (95% CI: 1.12, 3.69); paranoid 1.36% (95% CI: 0.42, 2.31); schizoid 0.56% (95% CI: -0.11, 1.23); schizotypal 1.05% (95% CI: 0.23, 1.87). Paranoid traits were predicted by decreasing self-esteem, increasing emotional and behavioral disorder symptoms, low agreeableness, and high neuroticism. Schizoid traits were predicted by decreased conscientiousness and agreeableness, increased social withdrawal, and a higher prevalence of Cluster A and B traits in parents. Schizotypal traits were predicted by high and increasing oddity and neuroticism, low conscientiousness, decreasing social competence, increasing emotional and behavioral symptoms, Cluster A traits in parents, and victimization from bullying. In conclusion, cluster A traits at age 16 can be predicted by a range of child-related factors already evident in preschool or 1st grade, most notably oddity, symptoms of emotional and behavioral disorders, low self-esteem, social withdrawal, and personality traits.