Comorbidity Treatment in Autism Spectrum Disorders and Intellectual Disabilities

Approved by Council June 17, 2013

Evidence supports an increased occurrence of psychiatric comorbidity in children with autism spectrum disorder (ASD), intellectual disability (ID), and related conditions. Unfortunately, little is known about the treatment of psychiatric comorbidity in the context of these disorders. Some research in this area has focused on disruptive behavior in ASD, including irritability (tantrums, aggression, self-injury) or hyperactivity. A paucity of research exists surrounding the treatment of formally diagnosed psychiatric comorbidity in ASD/ID.

Several reasons may account for the lack of evidence for treatment of psychiatric comorbidity in ASD/ID. Individuals with these disorders are routinely excluded from mental health treatment studies. Exclusion is not compatible with the ethical principle of justice in human research, which stipulates that the potential benefits of research should be applied equally unless there is some justification for differential treatment. Further, there is a lack of recognition of comorbid psychiatric disorders in research studies focused on ASD/ID. Consequently, treatment trials have targeted symptoms (irritability, hyperactivity), rather than comorbid psychiatric disorders. This separation reflects a poor integration of training and research in ASD/ID within the broader field of mental health, including within clinical research programs. The diagnostic instruments for ASD/ID are time intensive, and, while shorter screening instruments are available, they have not been routinely used. Further, available structured psychiatric interviews lack modules on ASD/ID.

AACAP supports efforts to include individuals with ASD/ID in research studies to better understand the course and treatment of psychiatric comorbidity in this group. To achieve this goal, AACAP advocates:

  1. Individuals with ASD/ID should not be routinely excluded in studies of mental health treatment of other conditions, unless there is a scientific reason for exclusion that is explicitly stated.
  2. NIH and other funders should consider grant supplements to encourage the inclusion of participants with ASD/ID in studies of a broad range of mental health treatments where small numbers or added assessment burden may otherwise limit inclusion. Similarly, funders should consider training grants or supplements that prepare treatment researchers to include individuals with ASD/ID.
  3. Publications of mental health research should routinely report the number of individuals with ASD/ID within the study population, when these data are available.




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