Prospective Associations between Anger and Later Internalizing Symptoms in Young Children with ASD

Background: Early negative emotionality is a risk factor for later difficulties in the general population, including internalizing symptoms and anxiety (Dougherty et al., 2015; Hernandez et al., 2015). Although intensity of anger in response to real-world challenges in toddlers with ASD was found to be greater than that of TD and DD peers (Macari et al., 2018), little is known about prospective relationships between anger and later internalizing symptoms including anxiety, which affect a large proportion of preschool- and school-age children with ASD (Gadow et al., 2004; Simonoff et al., 2008). The present study aims to address these gaps in knowledge.

Objectives: To examine the association between directly-observed and parent-reported anger in the second year and internalizing symptoms including anxiety at age 3.

Methods: Participants included 94 toddlers (Time1: M_age=22mo, range: 13-30mo; Time2: M_age=39mo, range: 33-47mo): 53 ASD and 41 typically-developing (TD). At Time1, anger was assessed both via parent report (ECBQ-Frustration) and directly (Laboratory Temperament Assessment Battery (Lab-TAB; Goldsmith & Rothbart, 1999). Intensity of emotional expression of anger (iEE-Anger) across facial and vocal channels was coded during three Lab-TAB episodes designed to elicit anger. At Time2, parents completed the Early Childhood Inventory (ECI-4; Internalizing composite) and the Preschool Anxiety Scales-Revised (PAS-R; Generalized Anxiety score).

Results: In the ASD group, Time1 iEE-Anger was correlated with the PAS-R Generalized Anxiety score at Time2 (r(30)=.377, p=.04), while iEE-Anger did not predict either Time2 measure in the TD group. Parent-reported ECBQ Frustration at Time1 in the ASD group was significantly and positively associated with PAS-R Generalized Anxiety (r(53)=.401, p=.003). In contrast, parent-reported ECBQ Frustration in the TD group was significantly associated with the ECI-Internalizing composite (r(41)=.550, p<.0001) but not with anxiety.

Conclusions:

This study suggests a significant role for anger in the development of anxiety and internalizing symptoms. Results indicated that expression of anger at age 2 measured both directly and via parent report predicted psychopathology a year later. In the ASD group, both directly-assessed and parent-reported anger at age 2 were associated with later generalized anxiety symptoms. This contrasted with TD toddlers, for whom parent-reported anger predicted later internalizing symptoms. Taken together, these preliminary results indicate that anger in toddlerhood is related to later anxiety in toddlers with ASD, but for TD children anger predicts a range of internalizing symptoms. Furthermore, prospective relationships suggested that pathways to these vulnerabilities may not be the same in children with TD and ASD. The data highlight the importance of a multi-method approach in understanding the development of internalizing symptoms and anxiety in young children with ASD.