Nine-year-old Johnny has had chronic grouchiness and severe temper outbursts since early childhood. At age 4, Johnny was asked to leave preschool because of his behavior and was diagnosed with ADHD. Stimulant treatment diminished the ADHD symptoms a lot and the irritability a bit. Johnny continued to have both chronic grouchiness and outbursts when frustrated; these occurred daily at home and weekly at school. Most outbursts were verbal, but some were physical. Most recently, he has been diagnosed with disruptive mood dysregulation disorder (DMDD), a new diagnosis unveiled in 2013 in DSM-5. His therapist and his child psychiatrist have tried a number of treatments. Parent training therapy seemed to help at first, but the behaviors returned. Both SSRIs and atypical antipsychotic treatment have been somewhat effective, but the antipsychotic caused significant sedation and weight gain.
Chronic irritability: An evolving perspective
In the 1990s and early 2000s, many clinicians might have diagnosed Johnny with bipolar disorder (BD). This might have happened even though the diagnosis would not have been justifiable using DSM-IV criteria, since Johnny had never had a manic episode. At the time, many child psychiatrists thought that pediatric BD presented with chronic irritability and symptoms of ADHD, rather than with the distinct manic episodes that characterize adult BD. Research subsequently showed that chronic irritability is not how BD presents in children (Leibenluft E, Am J Psychiatry 2011;168(2):129–142). As it turns out, chronically irritable children are not at increased risk to develop manic episodes as they age; instead, they are at increased risk for anxiety and unipolar depression later in life. Moreover, unlike children with BD, chronically irritable children do not tend to have unusually strong family histories of BD. Rather, there are both genetic and familial links between chronic irritability and unipolar depression.
This research created a quandary. Clearly, there are many children who are chronically irritable and who tend to develop depression and not mania. They suffer just as much as children with BD, but under DSM-IV, there wasn’t a distinct diagnosis for very severe, chronic irritability—a disturbance in mood—as the major problem. In an attempt to remedy this issue, the authors of DSM-5 included disruptive mood dysregulation disorder (DMDD) as a new diagnosis (Towbin K et al, J Am Acad Child Adolesc Psychiatry 2013;52:466–481).
Assessment and diagnosis
Irritability is among the most common reasons children are referred for psychiatric evaluation and care. In community studies, prevalence rates of severe irritability in children range from 2% to 5%. It is likely that you have and will see children with DMDD, possibly without recognizing them, so it is important to know how to make this diagnosis.
Johnny’s case illustrates the two core criteria for DMDD: temper outbursts and a generally irritable mood. The temper outbursts have to occur, on average, at least three times a week. Although temper outbursts are a common feature of many psychiatric illnesses, not many children have three outbursts a week on a regular basis. Some clinicians think that the outbursts in DMDD must have a physical component, but this is not true. In fact, the most common features of temper outbursts seen in youth with DMDD include yelling, screaming, or verbally threatening someone, without any physical components. For the DMDD diagnosis, your patient’s temper outbursts can be verbal (as most of Johnny’s were) and/or physical. Seriously consider the DMDD diagnosis if your patient is verbally argumentative, snappy, and apt to engage in name calling more frequently, intensely, and persistently than typical for someone that age.
Of course, most DMDD youth have occasional physical outbursts, even if their more typical outbursts are verbal. Physical temper outbursts can include slamming a door, throwing something down, kicking furniture, physically threatening someone (eg, clenching fists, raising an arm to hit), or destroying property (eg, kicking a hole in a wall, breaking belongings). The most severe (and rarest) temper outbursts cause harm towards another person. These behaviors include intentionally throwing an object directly at someone or physically pushing, shoving, slapping, or kicking someone.
The second core criterion for DMDD is pervasive irritable mood. To assess this, we ask parents whether they (and others) generally see the child as grouchy and grumpy. Caregivers of youth with DMDD often say they feel like they have to “walk on eggshells” for fear of upsetting their generally angry child. Throughout the day, the child is cranky and crabby, and the people in the child’s life see the child that way. When you assess a child for major depressive disorder, you have to determine whether the child is sad “most days most of the time.” For DMDD, it’s a very similar assessment; but, rather than focusing on sadness, you have to decide whether the child is cranky and crabby most of the time.
It’s important to note that parents often avoid certain activities (like going out to a restaurant or inviting another family to visit) and avoid asking the child to do things that they ask of the child’s siblings, such as homework or chores. If the parent accommodates the child by making very few requests in order to avoid an outburst and keep the child’s irritability under control, this should be noted. For example, some children will exhibit two outbursts per week, below the frequency criterion for DMDD, but parents will avoid making normal demands on the child and will refrain from enforcing a request in order to avoid or terminate an outburst. In these instances, the child meets the diagnostic criterion for DMDD. This is analogous to what you would do when you are assessing avoidance in a child with a possible anxiety disorder and there is substantial parental accommodation. Even if a child does not overtly express avoidance, you would still diagnose a child with anxiety disorder if the parents make accommodations that remove any opportunity for the child to either confront or avoid a feared object. The situation with DMDD is the same.
In DMDD, irritable mood has to be present for at least a year, but usually the mood has been present for much longer than that. Again, like temper outbursts, many children with psychiatric problems present with irritability. However, only a subset of these children will have persistent irritability that is present most days for a year, as is required for DMDD.