Comorbidity in ADHD
Purpose of Research: This research examined comorbidity with ADHD. Specifically, it looked at ODD/CD, depression, and anxiety that may co-occur with ADHD. The purpose was to determine if comorbidity with ADHD may actually represent unique disorders; therefore, warranting a separate category of a mental disorder or at least a subcategory.
The researchers used Cantwell’s approach as a guideline to determine if a disorder represent a separate this order. This approach provides for criteria for how a disorder could be consider distinct from other disorders. The guidelines are as follows: Clinical pharmacology, demographic correlates, psychosocial correlates, family factors, biological factors, response to treatment, and clinical outcomes.
Prior research by Jensen et al pointed toward evidenced to support the idea that ADHD with ODD/CD constitutes a unique subtype.
The current research found that ADHD with mood disorders, as well as ADHD with ODD/CD may constitute subtypes of ADHD. It found that these clients responded differently to treatment. For example, ADHD with mood disorders responded to all treatments. ADHD with ODD/CD responded only to medications and behavior therapy may be contraindicated. ADHD with mood disorders plus ODD/CD responded best to a combination of behavioral therapy and medication treatment.
The researchers noted that ADHD with mood disorders responded much better to treatment than clients with just ADHD or clients with ADHD and ODD/CD. In some ways, comorbid mood disorders offered ameliorating effects for these clients; thus, predicting better outcomes.
Method: 579 children were randomly selected from a clinical population and assigned to different treatment groups: meds, behavioral, combination of both, and community comparison. Treatment lasted 14 months. All children were previously diagnosed with ADHD, combined type. Other diagnoses were not considered and not children were excluded for having another diagnosis.
Average age was 8.2 years. The researchers administered various tests to evaluate for each of Cantwell’s criteria (see above). Afterwards, multivariate analysis was used to evaluate the data, as well as treatment effects.
As described above, different subgroups responded differently to treatment. This has implications when providing treatment for clients with ADHD. Having a thorough understanding of the symptoms experienced by clients, will help clinicians make better choices when choosing treatment options. For example, it may be important to know when medication is most effective and behavioral treatment is less effective.
Jensen, P.S., et al. (2001). ADHD comorbidity findings from the MTA study: Comparing
comorbid subgroups. Journal of American ACAD. Child Adolescent Psychiatry, 2. 147-158.