Developmental profiles of childhood attention-deficit/hyperactivity disorder and irritability: association with adolescent mental health, functional impairment, and suicidal outcomes

ADHD-related sex differences in emotional symptoms across development

To investigate developmental changes in emotion dysregulation (ED) and associated symptoms of emotional lability, irritability, anxiety, and depression, among girls and boys with and without ADHD from childhood through adolescence. Data were collected from a sample of 8-18-year-old children with (n = 264; 76 girls) and without (n = 153; 56 girls) ADHD, with multiple time-points from a subsample of participants (n = 121). Parents and youth completed rating scales assessing child ED, emotional lability, irritability, anxiety, and depression. Mixed effects models were employed to examine effects and interactions of diagnosis, sex [biological sex assigned at birth], age among boys and girls with and without ADHD. Mixed effects analyses showed sexually dimorphic developmental patterns between boys and girls, such that boys with ADHD showed a greater reduction in ED, irritability, and anxiety with age compared to girls with ADHD, whose symptom levels remained elevated relative to TD girls. Depressive symptoms were persistently elevated among girls with ADHD compared to boys with ADHD, whose symptoms decreased with age, relative to same-sex TD peers. While both boys and girls with ADHD showed higher levels of ED during childhood (compared to their sex-matched TD peers), mixed effects analyses revealed substantial sexually dimorphic patterns of emotional symptom change during adolescence: Boys with ADHD showed robust improvements in emotional symptoms from childhood to adolescence while girls with ADHD continued to show high and/or increased levels of ED, emotional lability, irritability, anxiety and depression.

The longitudinal relationship between socioemotional difficulties and irritability in ADHD

BACKGROUND

Despite higher rates of irritability and socioemotional symptoms in ADHD, consensus is lacking regarding their developmental relationship and whether it differs by ADHD status. This longitudinal study sought to evaluate how peer and emotional difficulties relate to irritability in ADHD and control groups.

METHODS

A community sample of 336 participants (45 % ADHD) were recruited for the Children's Attention Project. Participants completed the Affective Reactivity Index and the Strengths and Difficulties Questionnaire's emotional and peer difficulties scales at baseline (mean age 10.5 years) and 18-month follow-up. Latent Change Score models assessed how emotional and peer difficulties related to irritability at baseline and longitudinally.

RESULTS

For both groups, more severe baseline difficulties were associated with higher concurrent irritability, and reductions in emotional and peer difficulties were associated with declining irritability. Baseline emotional difficulties predicted change in irritability for the ADHD group, while baseline peer difficulties predicted change in irritability for both groups. Baseline irritability did not predict change in emotional or peer difficulties for either. The ADHD group showed elevated irritability, emotional, and peer difficulties, and stronger baseline correlation between peer difficulties and irritability.

LIMITATIONS

Only two timepoints were captured, and associations with ADHD symptom severity and presentation were not investigated. Doing so may facilitate additional insights.

CONCLUSIONS

Change in irritability corresponded to change in socioemotional difficulties, and was driven by earlier levels of socioemotional difficulties. ADHD exacerbated aspects of the relationship between socioemotional difficulties and irritability. Socioemotional difficulties drive irritability, so may represent targets for clinical interventions.

Irritability in Youths: A Critical Integrative Review

Irritability, defined as proneness to anger that may impair an individual's functioning, is common in youths. There has been a recent upsurge in relevant research. The authors combine systematic and narrative review approaches to integrate the latest clinical and translational findings and provide suggestions for addressing research gaps. Clinicians and researchers should assess irritability routinely, and specific assessment tools are now available. Informant effects are prominent, are stable, and vary by age and gender. The prevalence of irritability is particularly high among individuals with attention deficit hyperactivity disorder, autism spectrum disorder, and mood and anxiety disorders. Irritability is associated with impairment and suicidality risk independent of co-occurring diagnoses. Developmental trajectories of irritability (which may begin early in life) have been identified and are differentially associated with clinical outcomes. Youth irritability is associated with increased risk of anxiety, depression, behavioral problems, and suicidality later in life. Irritability is moderately heritable, and genetic associations differ based on age and comorbid illnesses. Parent management training is effective for treating psychological problems related to irritability, but its efficacy in treating irritability should be tested rigorously, as should novel mechanism-informed interventions (e.g., those targeting exposure to frustration). Associations between irritability and suicidality and the impact of cultural context are important, underresearched topics. Analyses of large, diverse longitudinal samples that extend into adulthood are needed. Data from both animal and human research indicate that aberrant responses to frustration and threat are central to the pathophysiology of irritability, revealing important translational opportunities.

Systematic Review and Meta-Analysis: Early Irritability as a Transdiagnostic Neurodevelopmental Vulnerability to Later Mental Health Problems

OBJECTIVE

Irritability is a transdiagnostic indicator of child and adolescent internalizing and externalizing problems that is measurable from early life. The objective of this systematic review was to determine the strength of the association between irritability measured from 0 to 5 years and later internalizing and externalizing problems, to identify mediators and moderators of these relationships, and to explore whether the strength of the association varied according to irritability operationalization.

METHOD

Relevant studies published in peer-reviewed, English-language journals between the years 2000 and 2021 were sought from EMBASE, PsycINFO, MEDLINE, CINAHL, and ERIC. We synthesized studies that included a measure of irritability within the first 5 years of life and reported associations with later internalizing and/or externalizing problems. Methodological quality was assessed using the JBI-SUMARI Critical Appraisal Checklist.

RESULTS

Of 29,818 identified studies, 98 met inclusion criteria, with a total number of 932,229 participants. Meta-analysis was conducted on 70 studies (n = 831,913). Small, pooled associations were observed between infant irritability (0-12 months) and later internalizing (r = 0.14, 95% CI = 0.09, 0.20) and externalizing symptoms (r = 0.16, 95% CI = 0.11, 0.21) symptoms. For toddler/preschool irritability (13-60 months), small-to-moderate pooled associations were observed for internalizing (r = 0.21, 95% CI = 0.14, 0.28) and externalizing (r = 0.24, 95% CI = 0.18, 0.29) symptoms. These associations were not moderated by the lag between irritability and outcome assessment, although the strength of the associations varied according to irritability operationalization.

CONCLUSION

Early irritability is a consistent transdiagnostic predictor of internalizing and externalizing symptoms in childhood and adolescence. More work is required to understand how to accurately characterize irritability across this developmental period, and to understand mechanisms underlying the relationship between early irritability and later mental health problems.

DIVERSITY & INCLUSION STATEMENT

One or more of the authors of this paper self-identifies as a member of one or more historically underrepresented racial and/or ethnic groups in science. One or more of the authors of this paper self-identifies as living with a disability. We actively worked to promote sex and gender balance in our author group. We actively worked to promote inclusion of historically underrepresented racial and/or ethnic groups in science in our author group.

STUDY PREREGISTRATION INFORMATION

Early irritability as a transdiagnostic neurodevelopmental vulnerability to early onset mental health problems: A systematic review; https://www.crd.york.ac.uk/prospero/; CRD42020214658.

Parsing between- and within-person effects: Longitudinal associations between irritability and internalizing and externalizing problems from early childhood through adolescence

INTRODUCTION

This report examines between- and within-person associations between youth irritability and concurrent and prospective internalizing and externalizing symptoms from early childhood through adolescence. Distinguishing between- and within-person longitudinal associations may yield distinct, clinically relevant information about pathways to multifinality from childhood irritability.

METHODS

Children's irritability and co-occurring symptoms were assessed across five waves between ages 3 and 15 years using the mother-reported Child Behavior Checklist (N = 605, 46% female). Parental history of depressive disorders was assessed with a clinical interview.

RESULTS

Results demonstrated that between- and within-person irritability were uniquely associated with concurrent depressive, anxiety, and defiance symptoms, but not ADHD. Prior wave within-person irritability also predicted next wave depressive, anxiety, and defiance symptoms, controlling for prior symptoms; these prospective associations were bidirectional. Child sex and parental depressive disorders moderated associations.

DISCUSSIONS

Findings identify pathways from within- and between-person irritability to later internalizing and externalizing psychopathology. Results demonstrate the importance of parsing within- and between-person effects to understand nuanced relations among symptoms over childhood.

Network analysis of anxiety and depression in the functionally impaired elderly

Background

Evidence from previous studies has confirmed that functionally impaired elderly individuals are susceptible to comorbid anxiety and depression. Network theory holds that the comorbidity emerges from interactions between anxiety and depression symptoms. This study aimed to investigate the fine-grained relationships among anxiety and depression symptoms in the functionally impaired elderly and identify central and bridge symptoms to provide potential targets for intervention of these two comorbid disorders.

Methods

A total of 325 functionally impaired elderly individuals from five communities in Xi'an, China, were recruited for our investigation. The GAD-7 and PHQ-9 were used to measure anxiety and depression, respectively. SPSS 22.0 software was used for descriptive statistics, and R 4.1.1 software was used for network model construction, expected influence (EI) evaluation and bridge expected influence (BEI) evaluation.

Results

In the network, there were 35 edges (indicating partial correlations between symptoms) across the communities of anxiety and depression, among which the strongest edge was A1 "Nervousness or anxiety"-D2 "Depressed or sad mood." A2 "Uncontrollable worry" and D2 "Depressed or sad mood" had the highest EI values in the network, while A6 "Irritable" and D7 "Concentration difficulties" had the highest BEI values of their respective community. In the flow network, the strongest direct edge of D9 "Thoughts of death" was with D6 "Feeling of worthlessness."

Conclusion

Complex fine-grained relationships exist between anxiety and depression in functionally impaired elderly individuals. "Uncontrollable worry," "depressed or sad mood," "irritable" and "concentration difficulties" are identified as the potential targets for intervention of anxiety and depression. Our study emphasizes the necessity of suicide prevention for functionally impaired elderly individuals, and the symptom "feeling of worthlessness" can be used as an effective target.

Psychometric properties of the Social Behavior Questionnaire (SBQ) in a longitudinal population-based sample

We assessed the psychometric properties of the Social Behavior Questionnaire (SBQ), a 30-item questionnaire evaluating social (e.g., disruptive behaviors, bullying) and emotional problems (e.g., anxiety, depression) among children aged 3.5–12 years. Children ( n = 1,950, 50.21% boys) were drawn from the Quebec Longitudinal Study of Child Development. Mothers reported the frequency with which children presented social and emotional behaviors from 3.5 to 8 years of age, and teachers from 6 to 12 years. We assessed internal structure using Confirmatory Factor Analysis, reliability using Cronbach’s alpha, and convergent and discriminant validity using a multitrait-multimethod (MTMM) approach. The six-factor (emotional distress, withdrawal, impulsive/hyperactive/inattentive, disruptive behaviors, prosocial behaviors, and peer relationships difficulties) structure of the SBQ showed good fit from ages 3.5 to 12 years. Reliability estimates were good to excellent (alphas > .7), and MTMM showed good convergent and discriminant validity. Overall, the SBQ presented good psychometric properties with a large population-based sample aged 3.5–12 years. Further studies should assess its screening potential by investigating its convergent validity with diagnostic information.

Convergent neural correlates of prenatal exposure to air pollution and behavioral phenotypes of risk for internalizing and externalizing problems: Potential biological and cognitive pathways

Humans are ubiquitously exposed to neurotoxicants in air pollution, causing increased risk for psychiatric outcomes. Effects of prenatal exposure to air pollution on early emerging behavioral phenotypes that increase risk of psychopathology remain understudied. We review animal models that represent analogues of human behavioral phenotypes that are risk markers for internalizing and externalizing problems (behavioral inhibition, behavioral exuberance, irritability), and identify commonalities among the neural mechanisms underlying these behavioral phenotypes and the neural targets of three types of air pollutants (polycyclic aromatic hydrocarbons, traffic-related air pollutants, fine particulate matter < 2.5 µm). We conclude that prenatal exposure to air pollutants increases risk for behavioral inhibition and irritability through distinct mechanisms, including altered dopaminergic signaling and hippocampal morphology, neuroinflammation, and decreased brain-derived neurotrophic factor expression. Future studies should investigate these effects in human longitudinal studies incorporating complex exposure measurement methods, neuroimaging, and behavioral characterization of temperament phenotypes and neurocognitive processing to facilitate efforts aimed at improving long-lasting developmental benefits for children, particularly those living in areas with high levels of exposure.

Childhood Irritability: Predictive Validity and Mediators of Adolescent Psychopathology

Despite its transdiagnostic significance, there is modest evidence with respect to the predictive validity of childhood irritability, especially across developmental periods; similarly, little is known about explanatory factors underlying these predictions. This study had two goals: (1) to test the predictive validity of childhood irritability with respect to adolescent internalizing and externalizing problems, controlling for baseline ADHD and related psychopathology and (2) to test theoretically-derived family (i.e., parenting behavior, parenting stress) and social (i.e., peer status, social skills) constructs as explanatory factors of adolescent psychopathology. Two hundred thirty ethnically diverse (51.5% White) 5-10-year-old youth (32% female) with (n = 121) and without (n = 110) ADHD completed three separate laboratory-based assessments across six to seven years. Temporally-ordered predictors, putative mediators, and psychopathology outcomes were assessed using multiple informants (i.e., parent, teacher, youth) and methods (i.e., structured interviews, normed rating scales). Controlling for demographic factors, clinical correlates, and baseline psychopathology, childhood irritability uniquely predicted adolescent externalizing problems, but not internalizing problems. Next, analyses revealed that low social skills partially explained predictions of adolescent internalizing problems. However, family or social factors did not underlie predictions of adolescent externalizing problems. These preliminary findings support the predictive validity of childhood irritability with respect to early adolescent externalizing problems and implicate low social skills as a potentially unique mediator of internalizing outcomes. Intervention-induced improvements in social skills may minimize emergent psychopathology initiated by significant childhood irritability.

ADHD and ODD Dimensions: Time Varying Prediction of Internalizing Problems from Childhood to Adolescence

OBJECTIVE

Although childhood ADHD is a risk factor for internalizing problems, it consists of separable inattention and hyperactivity dimensions that differentially predict outcomes. Oppositional defiant disorder also consists of separable dimensions (i.e., irritable, oppositional), co-occurs with ADHD, and predicts internalizing outcomes. To discern independent associations with internalizing problems, dimensions must be considered simultaneously.

METHODS

Controlling for age, sex, and race, we tested inattention, hyperactivity, irritability, and oppositionality as time-varying predictors of 6 to 7-year prospective change in parent- and teacher-rated internalizing problems in 230 ethnically- diverse (50% Caucasian) 5 to 10 year old youth (M = 7.4 years, 68% male) with (n = 120) and without ADHD (n = 110).

RESULTS

Escalating inattention and irritability, but not hyperactivity and oppositionality, uniquely predicted internalizing problems.

CONCLUSION

These findings suggest that inattention and irritability are unique risk factors for later internalizing problems. These dimensions may catalyze internalizing problems across development and constitute important intervention targets.

Concomitant Trajectories of Internalising, Externalising, and Peer Problems Across Childhood: a Person-centered Approach

This study investigated trajectories of concomitant internalising, externalising, and peer problems, and associated risk factors for group-membership, using a person-centered approach to better understand heterogeneity in subgroups identified. A cohort of 7,507 children in Ireland was followed from infancy to late childhood (50.3%, males; 84.9% Irish). The parent-version of the Strengths and Difficulties Questionnaire was used when children were 3, 5, 7 and 9 years of age. Information on antecedent risk factors was collected when children were 9 months. Group-based multi-trajectory modelling and multinomial logistic regression were used. Six subgroups of children with distinct profiles were identified, evidencing both homotypic and heterotypic comorbidity. No support of a ‘pure’ internalising, externalising or peer problems group was found in any identified trajectory group. Difficulties in one problem domain indicated the presence of difficulty in another problem domain for all children in elevated groups. Risk factors associated with group-membership were complex, with only three common factors across elevated groups: prenatal exposure to smoking, maternal education, and maternal stress. Specific risk factors for group-membership included low birth weight, sex, maternal age, maternal depression, family composition, social class, medical card status and quality of attachment. Despite some overlap in predictors, the combination of predictors specific to each group would suggest tailored programming. For children with the most acute problems, programming targets should include families with boys, born with low birth weight, exposed to smoking prenatally, with mothers who have lower levels of education, postnatal depression, increased stress and fewer financial resources.

Chronic Irritability in Youth: A Reprise on Challenges and Opportunities Toward Meeting Unmet Clinical Needs

This commentary focuses on irritability, one subtype of emotion dysregulation. We review literature demonstrating that irritability is not a developmental phenotype of bipolar disorder, but is longitudinally associated with unipolar depression and anxiety and genetically associated with unipolar depression, anxiety, and attention-deficit hyperactivity disorder. We describe how irritability is amenable to translational research, in part because of the relevance of frustrative nonreward, a model developed in rodents, to human irritability. Last, we demonstrate how such research has suggested a novel exposure-based intervention for irritability.

Cohort Profile: Quebec Longitudinal Study of Child Development (QLSCD)

PURPOSE

The Quebec Longitudinal Study of Child Development (QLSCD) was designed to examine the long-term associations of preschool physical, cognitive, social, and emotional development with biopsychosocial development across childhood, adolescence, and young adulthood.

METHODS

QLSCD is an ongoing prospective cohort including 2120 singletons born in 1997/1998 in the Canadian province of Quebec. So far, data have been collected annually or every 2 years from child ages 5 months to 21 years. The cohort currently includes 1245 participants. Data available include a range of environmental (e.g., family characteristics, child behaviour, educational attainment, mental health), biological (e.g., hair cortisol, genetic, epigenetic), and administrative data.

RESULTS

QLSCD has contributed to the understanding of children's psychosocial development, including the development of physical aggression and anxiety. QLSCD articles have advanced scientific knowledge on the influence of early childhood factors on childhood, adolescent, and young adult mental health, including the effect of participation in early childcare on cognitive and behavioural development, the developmental origins of adolescent and young adult mental health problems and suicide risk, and the development of interpersonal difficulties (e.g., peer victimisation) from preschool years to adolescence.

CONCLUSION

QLSCD has given major contributions to our understanding of the link between different aspects of child development and biopsychosocial development during the first two decades of life. Unique features include the presence of environmental, biological, and administrative data, long-term follow-up with frequent data collections, and use of data from multiple informants, including teachers, mothers, fathers, and the children themselves.

Irritability Predicts Hyperactive/Impulsive Symptoms Across Adolescence for Females

Irritability is common in Attention-Deficit Hyperactivity Disorder (ADHD), but little is known about whether irritability predicts the course of ADHD symptoms over time. Adolescence is a dynamic period of emotional development as well as shifts in ADHD symptoms; an important goal is to identify youth at risk of increasing or persisting symptoms. We examined irritability as a longitudinal predictor of change in adolescents' ADHD symptoms, as well as how this link may differ in females versus males. The sample included 108 youth (72 males) age 12-16 years (M = 14.21 years, SD = 1.44 years), 62 of whom met criteria for ADHD. Approximately 18 months later, 80 participants (48 males) were followed up at Time 2. A dimensional approach was used to examine changes over time in parent-reported inattentive and hyperactive/impulsive symptoms. Longitudinal path analysis revealed that irritability at Time 1 predicted higher relative hyperactive/impulsive symptoms at Time 2 after controlling for age and longitudinal stability in all variables. A multiple-group analysis examining moderation by sex/gender revealed that this association was significant only for females. These results suggest that irritability may play a key role in the persistence and worsening of hyperactive/impulsive symptoms across adolescence for females, with potential implications for the diagnosis and treatment of females with ADHD.