DMDD vs. Bipolar Disorder in Children: Diagnosis and Treatment

Introduction to DMDD and Its DSM-5 Context

Disruptive Mood Dysregulation Disorder (DMDD) is a condition characterized by chronic and severe irritability. It has been added to the fifth edition of the Diagnostic and Statistical Manual of Mental Disorders (DSM-5) to address adolescent and childhood mood disorders. DMDD is defined by severe temper outbursts that are disproportionate to the situation at hand and inconsistent with the child's developmental level. These outbursts occur multiple times per week. Between outbursts, the child's mood remains persistently irritable or angry, and symptoms must be present for between 12 and 17 months across multiple contexts. DMDD is not diagnosed in children under six years of age, though it is typically observed from age ten and above.

The inclusion of DMDD in DSM-5 also enabled the manual to address a controversial conversion regarding existing diagnoses. Support for DMDD is grounded in research on Severe Mood Dysregulation (SMD), a condition characterized by severe and chronic irritability together with hyperarousal symptoms. SMD shares symptoms with oppositional defiant disorder (ODD), depression, attention deficit hyperactivity disorder (ADHD), and mania. SMD was initially conceptualized as a possible bipolar disorder phenotype, though this view lacked substantial literature support. Longitudinal studies have since shown that dimensional and SMD measures of chronic irritability better predict unipolar anxiety and depressive disorders than bipolar disorder.

Bipolar Disorder in Children: Controversies and Overlaps

The traditional view holds that bipolar disorder can develop among pre-pubertal children, though it was considered rare and not a prevalent issue in adolescence. Symptom descriptions for young children were largely based on analyses drawn from adult populations (Shirazi, Shabani, & Shahrivar, 2014). Contrasting perspectives argue that bipolar disorder does occur in young children, including toddlers and preschoolers, but that its presentation differs from the adult form. According to these alternative views, the episodic nature characteristic of adult bipolar disorder is absent in young patients, and mood changes are far more common. In adults, aggressiveness, sleep disturbance, increased energy, and irritability are the more prominent symptoms — symptoms that children with bipolar disorder may also exhibit (Johnson & McGuinness, 2014). Proponents of this view maintain that bipolar disorder is frequently misdiagnosed or is co-morbid with ADHD, given the significant symptom overlaps between the two conditions in both children and adolescents.

Although uncommon, pre-pubertal children can present with DSM-IV-consistent criteria for bipolar disorder, and this demonstrates continuity with adult-form bipolar disorder and is associated with poor outcomes. The core controversy concerns whether bipolar disorder presents differently in children than in adults — a dispute similar to the one historically surrounding childhood depression, which was ultimately resolved by adopting adult diagnostic criteria with minor modifications (Meany-Walen, Bratton, & Kottman, 2014). In this context, the primary differences pertain to the definition of mood abnormality and the nature of episodes.

Some researchers and clinicians argue that the hallmark symptoms of manic episodes — abnormal, expansive, persistently elevated, or irritable moods and increased energy — are largely absent in children. Key questions include whether children with bipolar disorder resemble adults with the same illness and whether they experience episodes of severe non-episodic irritability (Manis, Norris, Paylo, & Kress, 2015). This speaks to the developmental presentation of pediatric mania versus the euphoria more commonly seen in adult mania. It is possible to identify groups of severely impaired children whose symptoms overlap with bipolar disorder across different ADHD presentations; however, most of these children do not meet the strict diagnostic criteria and may be developing a distinct disorder altogether. Current approaches focus on children with behavioral and emotional difficulties who exhibit hypomania or mania-like features, heightened irritability, and chronically unstable mood — a phenotype that has come to be described as severe mood dysregulation, equivalent in status to DMDD (Meany-Walen, Bratton, & Kottman, 2014).

Severe Mood Dysregulation and Neurological Findings

SMD includes hyperarousal symptoms similar to those seen in manic episodes and ADHD, along with severe, chronic, and non-episodic irritability. While researchers have observed that children and adolescents with bipolar disorder present with a narrow behavioral phenotype resembling adult bipolar disorder — including clear episodes of mania and depressed mood — SMD patients lack these well-defined episodes. Nevertheless, both bipolar disorder in young people and SMD are associated with comparable levels of functional impairment. Evidence indicates that SMD elevates the risk of early anxiety disorders and depressive disorders in adulthood, with a lower likelihood of bipolar disorder. This outcome is less frequently observed in the families of children with SMD compared to the families of children with bipolar disorder, across both clinical and community populations (Waxmonsky et al., 2013).

Children with ADHD show increased activation in the left amygdala — the brain region particularly associated with emotion. Compared to controls and SMD patients, children with bipolar disorder rate higher in subjective fear of neutral facial expressions, while SMD participants show under-activation in this region (Manis, Norris, Paylo, & Kress, 2015). Altered punishment and reward processing, which is relevant to a range of neuropsychiatric conditions, has been explored in preliminary research suggesting that SMD youths and individuals with bipolar disorder may not differ meaningfully from healthy controls — in contrast to individuals with psychopathy. Motor inhibition features are also relevant, particularly heightened neural recruitment resulting from failed motor inhibition, which distinguishes children with bipolar disorder from those with SMD. Studies on emotional prosody further reveal that deficits in identifying nonverbal emotional cues are present in SMD patients but not in controls, indicating that distinct brain mechanisms underlie SMD symptomatology. These mechanisms differ between SMD and bipolar disorder patients and require ongoing data updates to refine understanding (Meany-Walen, Bratton, & Kottman, 2014).

References

Johnson, K., & McGuinness, T. M. (2014). Disruptive mood dysregulation disorder: A new diagnosis in the DSM-5. Journal of Psychosocial Nursing, 52(2), 17–20.

Manis, A., Norris, R., Paylo, M. J., & Kress, V. E. (2015). Depressive, bipolar, and related disorders. In V. E. Kress & M. J. Paylo (Eds.), Treating Those With Mental Disorders (pp. 84–119). Columbus, Ohio: Pearson.

Meany-Walen, K. K., Bratton, S. C., & Kottman, T. (2014). Effects of Adlerian play therapy on reducing students' disruptive behaviors. Journal of Counseling and Development, 92, 47–56.

Shirazi, E., Shabani, A., & Shahrivar, Z. (2014). Disruptive mood dysregulation disorder and bipolar disorder: Convergence or divergence? Iranian Journal of Psychiatry & Clinical Psychology, 20(2), 95–110.

Waxmonsky, J. G., Wymbs, F. A., Pariseau, M. E., Belin, P. J., Waschbusch, D. A., & Babocsai, L. (2013). A novel group therapy for children with ADHD and severe mood dysregulation. Journal of Attention Disorders, 17(6), 527–541.