In Adolescents, Psychotic-Like Experiences Predict Future Psychiatric Illness

A community-based study published in Schizophrenia Research suggests an association between psychotic-like experiences (PLEs) in early adolescence and subsequent symptoms of psychiatric illness.

Johan Isaksson, PhD, and colleagues at Uppsala University, Sweden, abstracted data from a community-based prospective cohort of young adolescents born in 1997 and 1999 in the Swedish county of Västmanland. During wave 1 (2012) and wave 2 (2015) of the study, participants completed a self-report questionnaire by regular mail. The questionnaire captured sociodemographic characteristics, past-year PLEs, and internalizing (depression; anxiety) and externalizing (attention-deficit/hyperactivity disorder; conduct problems) symptoms. Hierarchical binary logistic regression models were used to assess the predictive validity of PLEs for psychiatric symptoms.

In the sample (n=1445; mean age, 14.38±1.04 years; 57.8% girls), more than a third (37.6%) of adolescents reported at least 1 PLE at either assessment, and 17.1% reported 4 or more. At wave 1, 18.4% and 27.8% of patients were categorized as having internalizing and externalizing symptoms, respectively; at wave 2, these numbers increased to 33.4% and 37%, respectively.

Per hierarchical modeling, PLEs at wave 1 were significantly associated with internalizing symptoms at wave 2 (odds ratio [OR], 1.09; 95% CI, 1.04-1.15; P =.001) after adjustments for age, sex, race/ethnicity, socioeconomic status, and baseline psychiatric symptoms. Internalizing symptoms at wave 2 were also significantly associated with internalizing symptoms at baseline (P <.001), externalizing symptoms at baseline (P =.025), female sex (P <.001), and non-Scandinavian ethnicity (P =.019).

The relationship between internalizing symptoms and PLEs was similar for probable depression (OR, 1.08; 95% CI, 1.03-1.14; P =.003) and anxiety disorder (OR, 1.11; 95% CI, 1.05-1.17; P <.001).

In addition, PLEs at baseline were nominally, although not significantly, associated with externalizing symptoms at wave 2 (OR, 1.04; 95% CI, 0.99-1.10; not significant). Instead, externalizing symptoms at wave 2 were predicted by internalizing symptoms at baseline (P =.044), externalizing symptoms at baseline (P <.001), and older age (P =.020). In post hoc analyses, PLEs were found to predict conduct problems, but not attention-deficit/hyperactivity disorder, 3 years later (OR, 1.08; 95% CI, 1.02-1.14; P =.012).

As study limitations, investigators cited the reliability issues associated with self-report, the lack of data available for mental health interventions, and the homogenous nature of the study cohort.

The investigators described PLEs as a potential “marker for psychiatric symptoms and as a putative antecedent for future psychopathology.” They further emphasized the importance of assessing PLEs in the stage of early adolescence.

Reference

Isaksson J, Vadlin S, Olofsdotter S, Åslund C, Nilsson KW. Psychotic-like experiences during early adolescence predict symptoms of depression, anxiety, and conduct problems three years later: a community-based study [published online October 30, 2019]. Schizophr Res. doi:10.1016/j.schres.2019.10.033