Prevalence, onset and progression of substance use in adolescents and young adults with Autism Spectrum Disorders - Project Summary Alcohol use and alcohol use disorders (AUD) in adolescents and young adults with autism spectrum disorders (ASD) have been considered rare by mental health professionals. This conclusion has primarily been based on clinical experience as the empirical literature on alcohol and other drug (AOD) use in the US is virtually nonexistent. Scandinavian health registry studies suggest AOD use is lower in the ASD population overall compared to the general public. Clinical studies also indicate lower rates of AOD in persons diagnosed with ASD compared to persons diagnosed with other psychiatric disorders. Nonetheless, rates of AOD use as high as 30% have been reported in the ASD population. In addition, there appear to be subgroups of persons with ASD, such as those with co-occurring Attention Deficit Hyperactivity Disorder (ADHD), with substantial rates of AOD use and AUDs that not only rival persons with other psychiatric disorders, but also indicate a need for proper identification and, when indicated, treatment. Importantly, prevalence estimates for ASD have increased in the past 10-20 years and a large proportion of that increase includes individuals with higher cognitive and language functioning. This subset of the ASD population is more likely to be included in and exposed to normative educational and social contexts, increasing risk for AOD use. The literature strongly supports the need for detailed and reliable information on the prevalence of AOD in a representative sample of adolescents and young adults with ASD in the US. In this application, we propose to assess a large, well-characterized, population-based ASD sample (Rhode Island Consortium for Autism Research and Treatment- RI-CART) that will enable us to provide, by far, the most in- depth characterization of AOD use and AUD prevalence in the ASD population in the US, as well as data regarding AOD onset and rate of progression to more severe use and AUDs. Equally important is the need to verify, or refute, risk and protective factors for AOD in this population. We will examine comorbid conditions, with specific focus on ADHD and anxiety disorders. We will also characterize the factors inducing risk of AOD use at critical junctions for adolescents and young adults with ASD, such as the transition to independent living, which is often associated with greater peer contact and less structure and social control. We propose to study a subsample of RI-CART participants (N=410) age 12-24 years, who either have an IQ ≥ 85 or an IQ ≥ 75 and are verbally fluent, in a 4-wave longitudinal, cohort-sequential study. We will examine AOD use in relation to age, as well as in relation to key developmental transitions (e.g., into and from high school, into supervised living or independent living/college).
