(PS8-D77) Impairment in Personality Functioning in Adolescents: Investigating Developmental Trajectory Classes and Co-development with Big-five Personality Traits, Emotion Regulation, and Psychopathology

Diagnosing and studying personality pathology in adolescence has long been a controversial topic. Nonetheless, research to date clearly shows that personality disorder features are present in adolescence. The Alternative Model for Personality Disorders (AMPD) which was introduced in Section III of the Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition (DSM-5) could facilitate the investigation of personality pathology in adolescence because it takes into account the dimensional nature of personality pathology. The two primary criteria of the AMPD are 1) a severity criterion (Criterion A), reflecting impairment in self (identity and self-regulation) and interpersonal (empathy, intimacy) functioning, and 2) Criterion B, reflecting five pathological personality traits and subtraits.

The present study aimed to investigate the developmental course of personality pathology in adolescence by means of Criterion A (impairment in personality functioning, IPF). Furthermore, we examined whether distinct developmental trajectory classes of IPF could be identified. The final goal of this study was to investigate if and how individuals among different trajectory classes of IPF develop differently over time with regard to Big-Five personality traits, emotion regulation, and psychopathological behaviors and symptoms.

A total of 1480 community adolescents (59.5% female) completed several questionnaires over the course of two years, resulting in three annual measurement waves. IPF was measured by means of the Five-Item Screening Scale for Personality Disorder (FISSPD; Skodol et al., 2011). Furthermore, participants completed questionnaires on Big-Five personality traits, emotion regulation strategies, eating disorder symptoms, depressive symptoms, non-suicidal self-injury (NSSI) and substance use. We used latent growth curve modeling (LGCM) and latent class growth analysis (LGCA) in order to answer our research questions.

Overall, levels of IPF remained constant throughout adolescence. Of note, however, is that our three-wave longitudinal design prevented us from estimating quadratic growth. When investigating observed mean levels of IPF, a quadratic trajectory peaking at age 16 may have been a better fit to the data, something that future research could investigate. Four developmental trajectory classes were found with regard to IPF: an adaptive class (comprising 24.8% of the sample), a normative class (43.3%), an at risk class (29.2%), and a disorder class (2.6%). Classes significantly differed regarding Big-Five personality traits, emotion regulation strategies, and psychopathological behaviors/symptoms. We will further discuss the results of this study, the strengths and limitations of the study, and implications of this study for future research and clinical practice.