Co-occurring autism and attention-deficit/hyperactivity disorder (ADHD) have been associated with poorer social skills. Most studies examining the association of ADHD symptoms and social skills in autism employ categorical and cross-sectional designs, which provide a narrow view of the development of ADHD symptoms. Using group-based trajectory modeling, we identified five trajectories of caregiver-reported attention problems in an inception cohort of autistic children (N = 393) followed from age 2–5 years (T1) to age 10.5–11 years (T8): Low-Stable (LS; 15.5% of participants), Low-Decreasing (LD; 25.2%), Low-Increasing (LI; 19.2%), Moderate-Decreasing (MD; 32.9%), and High-Stable (HS; 7.2%). Child FSIQ and caregiver age at baseline were lower and caregiver depression at baseline was higher for participants in the MD group than the LS group. Psychotropic medication use was associated with higher attention problems. The MD and HS groups had similar mean Vineland Adaptive Behavior Scales, Second Edition (VABS-II) Socialization standard scores at T8, which were lower than other groups. The LI group had lower Socialization scores than the LS group. Results support that a decline in caregiver-reported attention problems is common but not universal in autistic children and that even moderate/subclinical attention problems may relate to social skills outcomes in autism.

In the general population, irritability is associated with later depression. Despite irritability being more prevalent in autistic children, the long-term sequelae are not well explored. We tested whether irritability in early childhood predicted depression symptoms in autistic adolescents, and whether associations could be explained by difficulties in peer relationships and lower educational engagement. Analyses tested the longitudinal associations between early childhood irritability (ages 3–5) and adolescent depression symptoms (age 14) in a prospective inception cohort of autistic children (N = 390), followed from early in development shortly after they received a clinical diagnosis. Mediators were measured in mid-childhood (age 10) by a combination of measures, from which latent factors for peer relationships and educational engagement were estimated. Results showed early childhood irritability was positively associated with adolescent depression symptoms, and this association remained when adjusting for baseline depression. A significant indirect pathway through peer relationships was found, which accounted for around 13% of the association between early childhood irritability and adolescent depression, suggesting peer problems may partially mediate the association between irritability and later depression. No mediation effects were found for education engagement. Results highlight the importance of early screening and intervention for co-occurring irritability and peer problems in young autistic children.

Literature examining emotional regulation in infants with autism spectrum disorder (ASD) has focused on parent report. We examined behavioral and physiological responses during an emotion-evoking task designed to elicit emotional states in infants. Infants at an increased likelihood for ASD (IL; have an older sibling with ASD; 96 not classified; 29 classified with ASD at age two) and low likelihood (LL; no family history of ASD; n = 61) completed the task at 6, 12, and 18 months. The main findings were (1) the IL-ASD group displayed higher levels of negative affect during toy removal and negative tasks compared to the IL non-ASD and LL groups, respectively, (2) the IL-ASD group spent more time looking at the baseline task compared to the other two groups, and (3) the IL-ASD group showed a greater increase in heart rate from baseline during the toy removal and negative tasks compared to the LL group. These results suggest that IL children who are classified as ASD at 24 months show differences in affect, gaze, and heart rate during an emotion-evoking task, with potential implications for understanding mechanisms related to emerging ASD.

Although indirectly aggressive behavior and anxiety symptoms can co-occur, it is unclear whether anxiety is an antecedent or outcome of indirect aggression at the individual level and whether other personality traits can contribute to these longitudinal associations. Therefore, the between- and within-person associations among indirect aggression, anxiety symptoms, and empathic concern were examined across adolescence from ages 11 to 16 in a cohort of individuals followed annually (N = 700; 52.9% girls; 76.0% White) controlling for direct aggression and demographic variables. Results of autoregressive latent trajectory models with structured residuals supported an acting out model at the within-person level. Specifically, anxiety symptoms positively predicted indirect aggression and indirect aggression negatively predicted empathic concern at each adjacent time point. These findings suggest that methods of reducing worries about the self and increasing healthy self-confidence could prevent indirect aggression and help build concern and compassion toward others.

Understanding differences in social-emotional behavior can help identify atypical development. This study examined the differences in social-emotional development in children at increased risk of an autism spectrum disorder (ASD) diagnosis (infant siblings of children diagnosed with the disorder). Parents completed the Brief Infant-Toddler Social-Emotional Assessment (BITSEA) to determine its ability to flag children with later-diagnosed ASD in a high-risk (HR) sibling population. Parents of HR (n = 311) and low-risk (LR; no family history of ASD; n = 127) children completed the BITSEA when their children were 18 months old and all children underwent a diagnostic assessment for ASD at age 3 years. All six subscales of the BITSEA (Problems, Competence, ASD Problems, ASD Competence, Total ASD Score, and Red Flags) distinguished between those in the HR group who were diagnosed with ASD (n = 84) compared to non-ASD-diagnosed children (both HR-N and LR). One subscale (BITSEA Competence) differentiated between the HR children not diagnosed with ASD and the LR group. The results suggest that tracking early social-emotional development may have implications for all HR children, as they are at increased risk of ASD but also other developmental or mental health conditions.

Depression is associated with a multiplicity of adverse outcomes in adolescence, including peer victimization and low self-esteem. Depressive symptoms, peer victimization, and self-esteem are linked in cross-sectional studies, but no longitudinal study has been conducted assessing their developmental pathways in one integrated model across adolescence. We explored their temporal sequencing in a normative sample of 612 Canadian adolescents (54% girls) assessed annually over 5 years (Grade 7 to Grade 11). Potential confounders such as biological sex, ethnicity/race, and parent income and education were statistically controlled. We found evidence for the vulnerability model (self-esteem predicting depression) and the symptoms-driven model (depression predicting peer victimization). Our findings also supported the integration of these pathways into a self-perception driven model characterized by the indirect effect of self-esteem on later peer victimization via depressive symptoms. Specifically, poor self-esteem initiated a developmental cascade that led to poor mood and poor peer relations. These results highlight the importance of helping youth form a healthy identity that promotes positive mental health and peer relations, and the need to intervene with depressed, victimized, and at-risk adolescents to instill positive self-regard. Our results also emphasize the central role that self-perceptions play in the onset and maintenance of poor outcomes.

The codevelopment of symptoms of depression and socially prescribed perfectionism across adolescence (age 12–17) and non–age-overlapping childhood predictors (age 10–11) of joint trajectory group membership were examined in a sample of 700 Canadian youth. Results indicated that most adolescents (75.8%) followed a trajectory of low depression symptoms (low stable), whereas 15.7% followed an increasing trajectory (increasing), and 8.5% followed a trajectory that began high and decreased over time (high decreasing). More girls than boys were found in the increasing and high decreasing depression trajectories. Adolescents followed three distinct trajectories of socially prescribed perfectionism: 41.6% were in a low stable group, 40.5% in a moderate increasing group, and 17.9% in a high increasing group. Eight percent followed a high-risk dual trajectory of increasing depression and high increasing socially prescribed perfectionism. This joint trajectory was predicted by being bullied, anxious, and relationally aggressive (compared to the low-risk trajectory of low stable depression and perfectionism) at ages 10 and 11. These same predictors, along with poorer family functioning and lower family income, differentiated the joint high decreasing depression/high increasing perfectionism group from the low/low joint group, which comprised of 3.8% of the sample. The developmental progression was best characterized as depression leading to socially prescribed perfectionism. Implications for clinical practice are discussed.

The co-occurring development of internalizing and externalizing problems were examined in an inception cohort of 392 children diagnosed with autism spectrum disorder at age 3 who were assessed on four occasions. Results indicated that internalizing and externalizing problems were stable over time and highly comorbid. Joint trajectory analysis suggested that 13% of the sample followed a dual high-risk trajectory. High risk was not found to be associated with intellectual ability or autism spectrum disorder symptom severity but was linked to lower income and gender: more girls than boys were found in the high/stable internalizing problems trajectory. The results suggest that 1 in 4 preschoolers followed a trajectory of internalizing or externalizing problems (or a combination of the two) that could be characterized as clinically elevated.

Developmental cascade models linking childhood physical and relational aggression with symptoms of depression and attention-deficit/hyperactivity disorder (ADHD; assessed at ages 10, 11, 12, 13, and 14) to borderline personality disorder (BPD) features (assessed at age 14) were examined in a community sample of 484 youth. Results indicated that, when controlling for within-time covariance and across-time stability in the examination of cross-lagged relations among study variables, BPD features at age 14 were predicted by childhood relational aggression and symptoms of depression for boys, and physical and relational aggression, symptoms of depression, and symptoms of ADHD for girls. Moreover, for boys BPD features were predicted from age 10 ADHD through age 12 depression, whereas for girls the pathway to elevated BPD features at age 14 was from depression at age 10 through physical aggression symptoms at age 12. Controlling for earlier associations among variables, we found that for girls the strongest predictor of BPD features at age 14 was physical aggression, whereas for boys all the risk indicators shared a similar predictive impact. This study adds to the growing literature showing that physical and relational aggression ought to be considered when examining early precursors of BPD features.

A person-oriented approach was adopted to examine joint developmental trajectories of physical and indirect aggression. Participants were 1183 children aged 2 years at the initial assessment and followed over 6 years. Most children followed either low or declining trajectories of physical aggression (PA), but 14.6% followed high stable trajectories. Approximately two-thirds of participants followed low indirect aggression (IA) trajectories (67.9%), and one-third (32.1%) followed high rising trajectories. The results combining both PA and IA group memberships indicate that most children (62.1%) exhibit desisting levels of PA and low levels of IA. A significant proportion followed a trajectory of moderately desisting PA and rising IA (14.2%), and 13.5% followed high level trajectories of both forms of aggression. Virtually no children were high on one type and low on the other. Multinomial regressions analyses were used to predict joint trajectory group membership from selected child and family variables measured at 2 years. Young motherhood and low income predicted membership in the high PA-high IA trajectory, but only hostile parenting remained significant after family processes variables were entered in the model. Being a boy, young motherhood, and hostile parenting were generally associated with higher levels of PA. Girls were more likely than boys to follow a trajectory of desisting PA and rising IA. The results suggest that some children, mostly girls, reduce their use of PA and tend to increase their use of IA, and that highly physically aggressive children also tend to be highly indirectly aggressive. Early family risk characteristics and hostile parenting interfere with the socialization of aggression.This research was supported by research grants from Quebec's FQRSC and CIQSS, Canada's CIHR and SSHRC, the Canadian Institute for Advanced Research, the Molson foundation, St-Justine Hospital's Research Center, and the University of Montréal. We thank Danielle Forest (University of Montréal) for her work on data analysis and Franck Larouche (Statistics Canada) for his sustained commitment to assist us in managing the data.