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% (CI: 0.42, 2.31); schizoid 0.56% (CI: -0.11, 1.23); schizotypal 1.05% (CI: 0.23, 1.87). Elevated and rising levels of odd or eccentric behavior, heightened and increasing neuroticism, low conscientiousness, declining self-esteem, and growing emotional and behavioral difficulties predicted both paranoid and schizotypal features, whereas low and rising levels of insecure attachment predicted paranoid traits only. Schizotypal traits also shared early risk factors with schizoid traits: Problems with emotion regulation and cluster A traits in parents. Several assumed predictors were unpredictive: Having an imaginary friend, disorganized attachment, negative life-events, and autism spectrum symptoms. In conclusion, cluster A traits at age 16 can be predicted by a range of factors already evident in childhood and early adolescence, most notably oddity, symptoms of emotional and behavioral disorders, low self-esteem, social withdrawal, and personality traits.