This article critically reviews recent studies on individuals with intellectual disability who have an autism spectrum disorder (ASD) and experience higher rates of mental health problems than those without ASD. It suggests that recent studies do not provided enough evidence to support the hypothesis that adults with intellectual disability and ASD are more vulnerable to psychiatric disorders than those without ASD. Factors found to be associated with poorer mental health include severity of intellectual disability, adaptive behaviour skills and social skills.
Underwood, L., McCarthy, J., Tsakanikos, E. (2010). Mental health of adults with autism spectrum disorders and intellectual disability. Current Opinion in Psychiatry, Vol. 23(5), p. 421-6.