By Nestor Lopez-Duran PhD
The New York Times recently released two interesting reports about mental health issues in young children. The first examined the concept of preschool depression (see also here for one of our previous reviews about depression in young children). The second examined the practice of prescribing antipsychotic medications in young children. Both articles touched on an issue that is always present in all discussions about early childhood mental health: how do we differentiate between symptoms of a psychiatric disorders and normative behaviors that are expected at certain ages? Are we simply pathologizing childhood when we diagnosed conditions such as ADHD or Oppositional Defiant Disorder?
This debate is not limited to public discussions between some fringe anti-psychiatry movement and clinicians/researchers. Even clinicians vary to the extent that they are comfortable with diagnosing a young child with a psychiatric disorder. When I talk to my students about this issue I push them to take a pragmatic perspective. I ask two questions: 1) what evidence would you like to see that would make you conclude, with certainty, that a true disorder is present or not? And 2) if the disorder is present, what is the utility of the diagnosis?
Although there are many answers to these questions, most students focus on two issues. Is there continuity of this disorder/symptoms/behaviors? That is, if you diagnose a child with X, does the child continue to show the same symptoms over time? The assumption is that if the symptoms are temporary, it is possible that the symptoms are part of a normal phase of childhood (e.g., a physically aggressive 2 year old child). In contrast, if the symptoms become chronic over time, then it is more likely that we are not just seeing kids being kids, but that instead we are looking at something more serious. The second issue most students focus on is impairment. If the symptoms cause or lead to real impairment in the child’s educational, social, or family life (or occupational life in the future), then it is likely that we are not simply observing kids being kids. The assumption here is that normative behaviors in childhood should not lead you to experience significant impairment, such as getting arrested, being unable to make friends, being unable to attend school, etc. Both of these issues help us understand the question of utility: if a disorder is chronic and cause impairment, then providing a diagnosis may help the child obtain the right type of intervention and hopefully alter the disorders course.
In the recent issue of the Journal of Child Psychology and Psychiatry, Dr. Kate Kennan and a multidisciplinary team from multiple universities reported the results of a very timely study on the stability of Oppositional Defiant Disorder (ODD) and Conduct Disorder (CD) in early childhood. The authors wanted to examine what happen to children who are diagnosed with ODD or CD in early childhood. Specifically, how many of these kids continue to have ODD or CD 1, 2, or 3 years later. In essence, if a preschool child is diagnosed with ODD or CD, what are the odds that he/she will continue to show the same behaviors in the future?
To answer these questions the authors followed 223 preschoolers over a period of 3 years. This group included 123 kids who were referred to a clinic because of problems with aggression, defiance, or controlling temper. The rest served as a comparison group and were recruited from pediatrician offices. The children underwent a structured diagnostic interview at the beginning of the study, as well as 12, 24, and 36 months later.
Below is a graph showing the number of kids who continued to have the disorder or symptoms during the follow up period of the study.
As you can see, 84 children were diagnosed with ODD at intake. From these, 82% continued to have the disorder some time during the follow up period (anytime during the 12, 24, and 36-month evaluation). About 17% had some symptoms of ODD in the future, and only 1% didn’t show any symptoms of ODD during follow up. This sounds pretty discouraging but if you break the results by follow up period the results are not as grim. Specifically, of the kids diagnosed with ODD at the start of the study, 72% had the diagnosis after 12 months, 66% had it after 24 months, 52% had it after 36 months. That is, about ½ of the preschoolers diagnosed with ODD will continue to have ODD 3 years later.
The case with conduct disorder is very similar. 72 children were diagnosed with CD at intake. From these, 61% continued to have the disorder some time during the follow up. About 30% had some symptoms of CD in the future, and 8% didn’t show any symptoms of CD during follow up. Breaking down the data by year: Of the kids diagnosed with CD at the start of the study, 48% had the diagnosis after 12 months, 33% had it after 24 months, 26% had it after 36 months. That is, about 1/4 of the preschoolers diagnosed with CD will continue to have CD 3 years later.
It is clear from these results that ODD is significantly more stable than CD. That is, children diagnosed with ODD in preschool are very likely to continue to have the disorder 3 years later. In contrast, CD is less stable with only 26% having the disorder after 3 years. Now, remember that these children were referred to a clinic for treatment, which really impacts how we interpret these results. The fact that 50% of kids no longer have the diagnosis during the 3 year follow up appointment means that 50% kept the diagnosis EVEN after being accurately diagnosed in early childhood and (assuming) receiving treatment. We don’t know how chronic these diagnoses are among children who are not diagnosed or treated. Likewise, one could argue that the limited stability of CD may reflect that CD more responsive to intervention than ODD.
Yet, there was another finding that caught my attention. The kids with CD who would go on to have chronic CD, were significantly more impaired at intake that all other children. That is, children who meet diagnostic criteria for conduct disorder in preschool and are already very impaired (Ive seen families whose 4 year olds have been kicked out of 3 preschools already) are more likely than their less impaired peers to continue to struggle with conduct disorder in the future.
In summary, these conditions, especially ODD, are highly stable in a population of clinic referred children. This suggests that these children were not simply displaying normative behaviors of early childhood. The authors conclude:
What is known from the results of the present study, and from previously published reports on reliability and concurrent validity, is that CD does occur as early as the preschool period and that the vast majority of preschoolers who present for mental health services and meet criteria for ODD are not demonstrating transient oppositional behavior.
There is no doubt that some kids get misdiagnosed with psychiatric disorders for showing transient symptoms, but rejecting the idea that psychiatric disorders exist in childhood is inconsistent with the evidence and does little to help the affected children and their families.
Keenan, K., Boeldt, D., Chen, D., Coyne, C., Donald, R., Duax, J., Hart, K., Perrott, J., Strickland, J., Danis, B., Hill, C., Davis, S., Kampani, S., & Humphries, M. (2010). Predictive validity of DSM-IV oppositional defiant and conduct disorders in clinically referred preschoolers Journal of Child Psychology and Psychiatry DOI: 10.1111/j.1469-7610.2010.02290.x