Many children with disruptive mood dysregulation disorder have symptoms that also order, with such diagnoses often being present from a relatively early age. For some chil- dren, the criteria for major depressive disorder may also be met.
Genetic and physiological. In terms of familial aggregation and genetics, it has been suggested that children presenting with chronic, non-episodic irritability can be differen- tiated from children with bipolar disorder in their family-based risk. However, these two groups do not differ in familial rates of anxiety disorders, unipolar depressive disorders, or substance abuse. Compared with children with pediatric bipolar disorder or other men- tal illnesses, those with disruptive mood dysregulation disorder exhibit both commonal- ities and differences in information—processing deficits. For example, face-emotion labeling deficits, as well as perturbed decision making and cognitive control, are present in children with bipolar disorder and chronically irritable children, as well as in children with some other psychiatric conditions. There is also evidence for disorder-specific dys- function, such as during tasks assessing attention deployment in response to emotional stimuli, which has demonstrated unique signs of dysfunction in children with chronic ir- ritability.
Children presenting to clinics with features of disruptive mood dysregulation disorder are predominantly male. Among community samples, a male preponderance appears to be supported. This difference in prevalence between males and females differentiates disrup- tive mood dysregulation disorder from bipolar disorder, in which there is an equal gender prevalence.
In general, evidence documenting suicidal behavior and aggression, as well as other se- vere functional consequences, in disruptive mood dysregulation disorder should be noted when evaluating children with chronic irritability.
Chronic, severe irritability, such as is seen in disruptive mood dysregulation disorder, is associated with marked disruption in a child’s family and peer relationships, as well as in school performance. Because of their extremely low frustration tolerance, such children generally have difficulty succeeding in school; they are often unable to participate in the activities typically enjoyed by healthy children; their family life is severely disrupted by their outbursts and irritability; and they have trouble initiating or sustaining friendships.
Levels of dysfunction in children with bipolar disorder and disruptive mood dysregulation disorder are generally comparable. Both conditions cause severe disruption in the lives of the affected individual and their families. In both disruptive mood dysregulation disorder and pediatric bipolar disorder, dangerous behavior, suicidal ideation or suicide attempts, severe aggression, and psychiatric hospitalization are common.
Because chronically irritable children and adolescents typically present with complex histo- ries, the diagnosis of disruptive mood dysregulation disorder must be made while consid- ering the presence or absence of multiple other conditions. Despite the need to consider many other syndromes, differentiation of disruptive mood dysregulation disorder from bi- polar disorder and oppositional defiant disorder requires particularly careful assessment.