Developmental Trajectories of the P-factor From Childhood Through Adolescence

• In Event: Poster Session 08
  In Poster Session: PS 08 Topic - Developmental Psychopathology

Abstract

Introduction
The correlations and comorbidities of cross-disorder symptoms of psychopathology suggest the existence of a single continuous dimension of psychopathology termed the p-factor (Lahey et al., 2012). These phenotypic comorbidities additionally have a shared genetic basis which are present from an early age (Waldman et al., 2016). The early development of the p-factor has been largely unexplored, with just one study examining how the p-factor relates to psychopathology over multiple time-points during childhood and adolescence (Allegrini et al., 2020). Previous work on developmental trajectories of individual disorders over time have led to highly informative developmental taxonomies, such as Moffitt’s developmental taxonomy of antisocial behavior (Moffitt, 1993). This work has yet to begin for the general factor of psychopathology. This study will examine the developmental trajectories of the p-factor and additionally assess the heritability of these trajectories.

Method
Participants are from the Wisconsin Twin Panel (WTP), a birth-record-based cohort of twins born in Wisconsin beginning in 1989 (Schmidt et al, 2019). Visits assessing psychopathology occurred when children were approximately 7-8, 12-14, and 15-18 years old. The WTP used the MacArthur Health and Behavior Questionnaire (HBQ) and the Diagnostic Interview Schedule for Children (DISC-IV) to assess symptoms of psychopathology over three laboratory visits when twins were between the ages of 5 and 20. The Berkeley Puppet Interview (BPI), a child self-report interview, was additionally conducted at the first visit. Symptomatology was assessed through at least one measure in approximately N = 3,800 individuals at the first visit, N = 1,000 at the intermediate visit, and N = 1,100 at the last visit.

Analytic Plan
First, we will conduct a bifactor analysis, which we anticipate will produce a p-factor and additional lower-order factors (i.e., an ADHD factor, depression factor, etc.) at each age (Tackett et al., 2013). This will be followed by bivariate twin analyses to calculate heritability for the p-factor and lower-order factors.

Next, we will use growth mixture modeling to construct growth curves of the p-factor over the three time points. We will identify different trajectories of general factors of psychopathology. We will examine the influence of genes and environment on the intercept and slope of each trajectory to determine whether there are differences in heritability for the base level and rate of change of the trajectories.

Discussion
We aim to examine the prominence of a p-factor throughout middle childhood and late adolescence. Examining heritability will allow for a comparison of the role of genetics and environment in the higher and lower order factors and how these influences change over time. Finally, the subsequent analysis of the trajectories of the p-factor will inform the normative patterns of symptoms of psychopathology in a community sample. Charting the course of general risk for psychopathology as such is consistent with the goals of the The Hierarchical Taxonomy of Psychopathology (HiTOP; Kotov et al., 2017).

All data is already collected; the planned analyses are feasible by the time of the conference.

Authors

• Emily Hilton, University of Wisconsin - Madison
  Presenting Author

• H Hill Goldsmith, University of Wisconsin - Madison
  Non-Presenting Author