ADHD and the Development of Depression: Commentary on the Prevalence, Proposed Mechanisms, and Promising Interventions

Does comorbid depression impact executive functioning (EF) in adults diagnosed with ADHD?: a comparison of EF across diagnoses in clinically-referred individuals

INTRODUCTION

Executive functioning (EF) is a salient factor in both ADHD as well as depressive disorders. However, sparse literature has examined whether depression severity impacts EF concurrently among adults with ADHD. The goal of this study was to examine differences in EF between adult patients diagnosed with ADHD and those diagnosed with a non-ADHD primary psychopathological condition, as a function of both ADHD presentation and depression severity in a diverse clinical sample.

METHOD

This crosssectional study included 404 adult patients clinically referred for neuropsychological evaluation to assist with differential diagnosis and/or treatment planning related to known or suspected ADHD. Various EF tasks and a measure of depression severity were administered. One-way MANOVA analyses were conducted to compare EF performance between individuals diagnosed with ADHD or a non-ADHD primary psychopathological condition, with additional analyses examining group differences based on ADHD presentation and depression severity. Regression analyses also examined the potential contribution of depression severity to each EF measure within each group.

RESULTS

No significant EF performance differences were found when comparing individuals diagnosed with ADHD and those with a non-ADHD primary psychopathological condition, nor based on ADHD presentation. When comparing across groups using cut-offs for high or low depression, only one EF measure showed significant differences between groups. Further, depression severity generally did not predict reduced EF performances with the exception of verbal fluency and working memory performances in select groups.

CONCLUSIONS

This study demonstrated that individuals with ADHD generally perform comparably on EF measures regardless of the presence or absence of comorbid depression. These results suggest further examination of EF deficits when they emerge for adults with ADHD, especially beyond comorbid depression severity.

Assessment of 'Cool' and 'Hot' Executive Skills in Children with ADHD: The Role of Performance Measures and Behavioral Ratings

Executive dysfunction is an underlying characteristic of Attention Deficit/Hyperactivity Disorder (ADHD). Therefore, this study explored which measures of executive functions (EF) may lead to a better diagnostic prediction and evaluated whether participants were adequately assigned to the ADHD group based on the identified predictors. Seventeen 6- to 10-year-old children with ADHD were matched with 17 typically developing peers (TD) by age, gender, and non-verbal intelligence. Performance-based measures and behavior ratings of 'cool' and 'hot' EF were used. As expected, there was a significant group effect on the linear combination of measures, indicating that children with ADHD showed significant difficulties with EF compared to the TD group. In fact, significant differences were found in measures of short-term and working memory, planning, delay aversion, and EF-related behaviors, as reported by parents and teachers. However, the discriminant function analysis only revealed three significant predictors: the General Executive Composite of the Behavior Rating Inventory of Executive Function (Parent and Teacher Forms) and the Delay of Gratification Task, with 97.1% correct classifications. These findings highlight the importance and contribution of both behavioral ratings and 'hot' measures of EF for the characterization of ADHD in children.

Childhood ADHD and Executive Functioning: Unique Predictions of Early Adolescent Depression

Given the increasing prevalence of adolescent depression, identification of its early predictors and elucidation of the mechanisms underlying its individual differences is imperative. Controlling for baseline executive functioning (EF), we tested separate ADHD dimensions (i.e., inattention, hyperactivity-impulsivity) as independent predictors of early adolescent depression, including temporally-ordered causal mediation by academic functioning and social problems, using structural equation modeling. At baseline, participants consisted of 216 children (67% male) ages 6-9 years old with (n = 112) and without (n = 104) ADHD who subsequently completed Wave 2 and 3 follow-ups approximately two and four years later, respectively. Predictors consisted of separate parent and teacher ratings of childhood ADHD and laboratory-based assessments of key EF domains. At Wave 2, parents and teachers completed normed rating scales of youth academic and social functioning; youth completed standardized assessments of academic achievement. At Wave 3, youth self-reported depression. Baseline inattention positively predicted early adolescent depression whereas childhood hyperactivity-impulsivity and EF did not. Neither academic nor social functioning significantly mediated predictions of depression from baseline ADHD and EF. We consider prediction of early adolescent depression from inattention, including directions for future intervention and prevention research.

Longitudinal network model of the co-development of temperament, executive functioning, and psychopathology symptoms in youth with and without ADHD

Attention-deficit hyperactivity disorder (ADHD) is a common, chronic, and impairing disorder, yet presentations of ADHD and clinical course are highly heterogeneous. Despite substantial research efforts, both (a) the secondary co-occurrence of ADHD and complicating additional clinical problems and (b) the developmental pathways leading toward or away from recovery through adolescence remain poorly understood. Resolving these requires accounting for transactional influences of a large number of features across development. Here, we applied a longitudinal cross-lagged panel network model to a multimodal, multilevel dataset in a well-characterized sample of 488 children (nADHD = 296) to test Research Domain Criteria initiative-inspired hypotheses about transdiagnostic risk. Network features included Diagnostic and Statistical Manual of Mental Disorders symptoms, trait-based ratings of emotional functioning (temperament), and performance-based measures of cognition. Results confirmed that ADHD symptom domains, temperamental irritability, and working memory are independent transdiagnostic risk factors for psychopathology based on their direct associations with other features across time. ADHD symptoms and working memory each had direct, independent associations with depression. Results also demonstrated tightly linked co-development of ADHD symptoms and temperamental irritability, consistent with the possibility that this type of anger dysregulation is a core feature that is co-expressed as part of the ADHD phenotype for some children.

Dependent Stress Mediates the Relation Between ADHD Symptoms and Depression

Objective: Depression and attention-deficit hyperactivity disorder (ADHD) are prevalent and highly comorbid. ADHD symptoms are associated with specific dependent (i.e., self-generated) stressors in children, and there is a strong link between dependent stress and depression. Despite continued comorbidity of ADHD and depressive symptoms into adulthood, it is unknown whether stress generation mediates the relation between ADHD and subsequent depressive symptoms in emerging adulthood, a period of heightened stress. Method: We tested this mediation model in a semester-long longitudinal study of 224 college students (aged 18-23 years). We additionally tested whether this model differed between inattentive versus hyperactive/impulsive ADHD symptoms given evidence that they vary in their relations to stress and depression. Results: Dependent stress mediated the association between total ADHD symptoms at baseline and later depressive symptoms; these effects were equivalent for inattentive versus hyperactive/impulsive ADHD symptoms. Conclusion: These findings suggest stress generation as a mechanism for increased depression in individuals with ADHD symptoms.

Presenting problem profiles for adolescents with ADHD: differences by sex, age, race, and family adversity

BACKGROUND

Adolescents with attention-deficit/hyperactivity disorder (ADHD) experience developmentally distinct challenges from children and adults with ADHD. Yet no work in this age group identifies treatment-related phenotypes that can inform treatment matching, development of tailored treatments, and screening efforts.

METHOD

This study uses Latent Profile Analysis to detect unique presenting problem profiles among adolescents with ADHD and to test whether these profiles differ by key individual characteristics (age, sex, race, family adversity level). Participants were 854 ethnically diverse adolescents (ages 10-17) from the ADHD Teen Integrative Data Analysis Longitudinal (TIDAL) dataset who were assessed at clinical referral. Parent, adolescent, and teacher ratings, educational testing, and school records measured eight key presenting problems at intake.

RESULTS

A three-profile solution emerged. ADHD simplex (63.7%) was characterized by a mix of the ADHD-Inattentive and ADHD-Combined subtypes, moderate impairment levels, and infrequent comorbidities. ADHD + internalizing (11.4%) was characterized by higher likelihood of comorbid anxiety and/or depression. The disruptive/disorganized ADHD (24.9%) profile was characterized by severe organization, time management, and planning (OTP) problems, the ADHD-Combined subtype, and frequent disruptive behavior at school. Age did not vary across these phenotypes. More females were present in the ADHD + internalizing phenotype; males were more likely to be found in the disruptive/disorganized ADHD phenotype. Higher family adversity and African American race were associated with the disruptive/disorganized ADHD phenotype.

CONCLUSIONS

Adolescents with ADHD demonstrate varying presenting problem phenotypes that vary by sex, family adversity, and race/ethnicity. Consideration of these phenotypes may inform treatment matching and efforts to improve screening among under-diagnosed groups.

Impact of sleep restriction on affective functioning in adolescents with attention-deficit/hyperactivity disorder

BACKGROUND

Shortened sleep and affective disturbances are both prevalent in adolescents with attention-deficit/hyperactivity disorder (ADHD), yet the causal link between these domains has not been examined. This study investigated whether shortened sleep duration is causally linked to affective functioning in adolescents with ADHD.

METHODS

Participants were 48 adolescents (75% male) aged 14-17 years with ADHD who successfully completed a three-week sleep protocol using an experimental crossover design. The protocol included a phase stabilization week, followed, in randomized counterbalanced order, by one week of sleep restriction (6.5 hr in bed) and one week of sleep extension (9.5 hr in bed). Sleep was monitored with objective actigraphy, and all participants included in this study obtained ≥1 hr actigraphy-measured sleep duration during extension compared to restriction. Parents and adolescents provided daily ratings of positive and negative affect during the extension and restriction conditions. Ratings of affect, internalizing symptoms, and emotion regulation were collected at laboratory visits conducted at the end of each week.

RESULTS

Both parents and adolescents reported greater depressive symptoms and lower positive affect during restriction compared to extension. Parents also reported greater negative affect and emotion dysregulation among adolescents during sleep restriction than extension. No effects were found for parent- or adolescent-reported anxiety symptoms or for adolescent-reported emotion regulation or negative affect.

CONCLUSIONS

Findings from this study provide the first evidence that shortened sleep duration is a causal contributor to the affect and mood disturbances frequently experienced by adolescents with ADHD, particularly as observed by parents. Targeting sleep may be important to reduce affective disturbances in adolescents with ADHD.

Temporal and Reciprocal Relations Between ADHD symptoms and Emotional Problems in School-Age Children

Objective: The study aimed to investigate the reciprocal and temporal relations between ADHD symptoms and emotional problems in school-age children. Method: This 1-year longitudinal study with a four-wave design included 1,253 children and adolescents (254 third graders, 281 fifth graders, and 718 eighth graders; 50.9% boys). ADHD symptoms and emotional problems were measured using parent report of the Swanson, Nolan, and Pelham, Version IV Scale and Strengths and Difficulties Questionnaire. Results: Cross-lagged panel analyses indicated that both inattention and hyperactivity/impulsivity symptoms were associated with emotional problems over the 1-year period. However, only inattention symptoms demonstrated a transactional relationship with emotional problems, such that inattention predicted future emotional problems, which in turn led to increases in inattention symptoms. Conclusion: Our findings highlight the transactional and dynamic interplay between inattention symptoms and emotional problems and support the mechanistic role of inattention symptoms in the development and persistence of emotional problems in school-age children.

Association of ADHD and Executive Functioning With Childhood Depression

Objective: Despite its association with increased severity and treatment resistance, relatively little is known about the correlates of early-onset childhood depression. ADHD and executive functioning (EF) are each related to depression. Given their covariation, we tested the independent association of ADHD dimensions (i.e., inattention, hyperactivity) and EF with childhood depression using structural equation modeling to identify potential targets for intervention. Method: Participants were 225 five- to 10-year-old children (68% male) with (n = 117) and without (n = 108) ADHD. Youth completed laboratory assessments of EF, and parent, teacher, and youth reports of depression were gathered. Results: With control of EF and anxiety, across informants, inattention, but not hyperactivity, was positively related to child depression. EF was positively associated with depression according to parent ratings only. Conclusion: We consider the association of inattention and EF with childhood depression, including implications for intervention and prevention from a developmental psychopathology framework.