Executive function in children with disruptive mood dysregulation disorder compared to attention-deficit/hyperactivity disorder and oppositional defiant disorder, and in children with different irritability levels.

Addressing current challenges in research on disruptive mood dysregulation disorder (DMDD), this study aims to compare executive function in children with DMDD, children with attention-deficit/hyperactivity disorder (ADHD), and children with oppositional defiant disorder (ODD). We also explore associations between irritability, a key DMDD characteristic, and executive function in a clinical sample regardless of diagnosis. Our sample include children (6-12 years) referred to child psychiatric clinics. Measures of daily-life (parent-reported questionnaire) and performance-based (neuropsychological tasks) executive function were applied. Identifying diagnoses, clinicians administered a standardized semi-structured diagnostic interview with parents. Irritability was assessed by parent-report. First, we compared executive function in DMDD (without ADHD/ODD), ADHD (without DMDD/ODD), ODD (without DMDD/ADHD) and DMDD + ADHD (without ODD). Second, we analyzed associations between executive function and irritability using the total sample. In daily life, children with DMDD showed clinically elevated and significantly worse emotion control scores compared to children with ADHD, and clinically elevated scores on cognitive flexibility compared to norm scores. Children with DMDD had significantly less working memory problems than those with ADHD. No differences were found between DMDD and ODD. Increased irritability was positively associated with emotional dyscontrol and cognitive inflexibility. For performance-based executive function, no diagnostic differences or associations with irritability were observed. We discuss how, in daily life, children with high irritability-levels get overwhelmed by feelings without accompanying regulatory capacities.

Neuropsychological mechanisms of social difficulties in disruptive mood dysregulation disorder versus oppositional defiant disorder.

Children with Disruptive Mood Dysregulation Disorder (DMDD) or Oppositional Defiant Disorder (ODD) are characterized by irritability and social difficulties. However, the mechanisms underlying these disorders could be different. This study explores differences in social cognition and executive function (EF) across DMDD and ODD and the influence of these factors and their interaction on social problems in both groups. Children with DMDD (n = 53, Mage = 9.3) or ODD (n = 39, Mage = 9.6) completed neuropsychological tasks measuring social cognition (Theory of Mind and Face-Emotion Recognition) and EF (cognitive flexibility, inhibition, and working memory). Parents reported social problems. More than one-third of the children with DMDD and almost two-thirds of those with ODD showed clear difficulties with Theory of Mind. Most children with DMDD (51-64%) or ODD (67-83%) showed difficulties with EF. In children with DMDD, worse EF (ß = -.36) was associated with more social problems, whereas in children with ODD, better EF (ß = .44) was associated with more social problems. In those with ODD, but not in those with DMDD, the interaction between social cognition and EF contributed to the explained variance of social problems (ß = -1.97). Based on the observed interaction pattern, enhanced EF may lead to increased social problems among children with ODD who also exhibit social cognition difficulties. This study suggests the existence of distinct neuropsychological mechanisms underlying the social issues observed in children with DMDD versus those with ODD.

Disruptive Mood Dysregulation Disorder in a Norwegian Clinical Child Population.

BACKGROUND: Disruptive Mood Dysregulation Disorder was included in DSM-5 to accommodate new research addressing aspects of emotional dysregulation in children suffering from disruptive behavior problems. Despite growing interest in Disruptive Mood Dysregulation Disorder, few studies have looked at prevalence rates in European clinical populations. The primary objective of this study was to examine the prevalence and characteristics associated with Disruptive Mood Dysregulation Disorder in a Norwegian clinical sample. METHODS: The present study assessed children 6-12 years of age referred to a mental health clinic for evaluation and treatment (N = 218, Mage = 9.6, 60.4% boys) and compared those who did and did not meet Disruptive Mood Dysregulation Disorder diagnostic criteria. Diagnoses were determined using K-SADS-PL 2013. Associated difficulties at home and in school were measured by Achenbach Systems of Empirically Based Assessment battery. RESULTS: In this clinical sample, 24% met the diagnostic criteria for Disruptive Mood Dysregulation Disorder. Children with Disruptive Mood Dysregulation Disorder were more likely than those without Disruptive Mood Dysregulation Disorder to be male (77% vs. 55%, p = .008), be living in poverty, have multiple mental health diagnoses (79% vs. 53%, p = .001), and have lower global functioning levels as measured by Children's Global Assessment Scale (range 0-100, M = 47, SD = 8.5 vs. M = 57, SD = 11.4, p=<.001). Finally, parents and teachers of children with Disruptive Mood Dysregulation Disorder reported lower overall competence and adaptive functioning, and higher total symptom load than children with other diagnoses. CONCLUSION: Disruptive Mood Dysregulation Disorder is highly prevalent in a Norwegian clinical sample and displays a high symptom load. Our results are in accordance with similar studies. Consistent findings across the world may support Disruptive Mood Dysregulation Disorder as a valid diagnostic category.

Excessive hair cortisol concentration as an indicator of psychological disorders in children.

Cortisol in hair is a new biomarker assessing long-term hypothalamic-pituitary-adrenal (HPA) axis activity, which is related to emotion regulation. We compare hair cortisol concentrations (HCC), in clinically referred children with disruptive mood dysregulation disorder (DMDD) (n = 19), children with other types of psychological disorders (n = 48), and healthy subjects (n = 36). We also investigate the association between HCC and irritability, age, and sex. Our results show that children with DMDD or other types of psychological disorders have higher HCC than healthy subjects, p < .001, ηp2 = .39. No difference between children with DMDD and those with other types of psychological disorders was found, p = .91, nor an association between HCC and irritability in the clinical sample, p = .32. We found a significant negative correlation between HCC and age in those with DMDD, r = -0.54, p < .05, but not in the normative sample, r = -0.20, p = .25. No differences in HCC between girls and boys were found in the normative sample, p = .49. Children in need of psychological treatment, including those with DMDD, seem to have dysregulated HPA-axis activity over time. Excessive accumulated cortisol concentrations in hair could be an indicator of a psychological disorder in children.

Underlying mechanisms of disruptive mood dysregulation disorder in children: A systematic review by means of research domain criteria.

Background: A systematic overview of underlying mechanisms in the new disruptive mood dysregulation disorder (DMDD) diagnosis is needed. The Research Domain Criteria (RDoC) represent a system of six domains of human functioning, which aims to structure the understanding of the nature of mental illnesses. By means of the RDoC framework, the objective of this systematic review is to synthesize available data on children and youths <18 years suffering from DMDD as reported in peer reviewed papers. Methods: A literature search guided by PRISMA was conducted using Medline, PsychInfo, and Embase, while the RDoC domains were employed to systematize research findings. Risk of bias in the included studies was examined. Results: We identified 319 studies. After study selection, we included 29 studies. Twenty-one of these had findings relating to >1 RDoC domain. The risk of bias assessment shows limitations in the research foundation of current knowledge on mechanisms of DMDD. Discussion: Reviewing self-report, behavior and neurocircuit findings by means of RDoC domains, we suggest that DMDD youths have a negative interpretation bias in social processes and valence systems. In occurrence of a negative stimuli interpretation, aberrant cognitive processing may arise. However, current knowledge of DMDD is influenced by lack of sample diversity and open science practices. Conclusion: We found the six RDoC domains useful in structuring current evidence of the underlying mechanisms of DMDD. Important opportunities for future studies in this field of research are suggested. In clinical practice, this comprehensive summary on DMDD mechanisms can be used in psychoeducation and treatment plans.