Handbook of Intellectual Disabilities

Abstract

Although it was historically assumed that mental health conditions such as anxiety disorders did not exist in individuals with intellectual disabilities (ID), it is increasingly being recognized that individuals with ID do experience fear and anxiety, at increased rates compared to the general population. This chapter provides an overview of the diagnostic criteria for the various anxiety disorders in the Diagnostic and Statistical Manual of Mental Disorders (DSM-5), how these criteria should be modified for individuals with ID, and how to assess anxiety in individuals with ID using a multi-method assessment strategy that includes behavioral, cognitive/affective, and physiological indicators of anxiety. We also review the evidence base for interventions that have been used to treat anxiety or phobic avoidance in individuals with ID. We found that in vivo exposure, contingent reinforcement, hierarchy/shaping/stimulus fading, prompting, modeling, noncontingent reinforcement, increasing predictability, and relaxation can be classified as efficacious interventions for treating anxiety in ID, with other interventions classified as possibly efficacious or not having enough evidence. These classifications must be viewed with caution, given that evaluating the quality or methodological rigor of these studies was beyond the scope of this chapter. Overall, behavioral interventions as a whole can be considered efficacious for the treatment of phobic avoidance and anxiety (though not necessarily as a treatment for DSM-5 anxiety disorders) in individuals with ID, with exposure and contingent reinforcement being the most commonly used and well-established interventions. Limitations of the existing intervention research as well as directions for future research are discussed.