Diagnostic complexities of autism and psychosis: A commentary on the ANZJP GRADE guidelines for the management of schizophrenia

Abstract

The Australian and New Zealand Journal of Psychiatry GRADE Evidence Guidelines for Schizophrenia highlight the importance of considering psychiatric comorbidities, including autism spectrum disorder. These guidelines acknowledge that there is limited empirical research to guide the management of individuals with schizophrenia who also have these comorbid conditions. This lack of evidence poses challenges for clinicians, especially those working in early psychosis services, where the possibility of a missed diagnosis of autism spectrum disorder is increasingly being examined, and pre-existing diagnoses of autism spectrum disorder are not uncommon. This commentary explores the complex overlaps among shared histories, risk factors and symptomatology, as well as the difficulties stemming from the absence of validated assessment tools to aid in diagnostic clarification. Psychotic symptoms may complicate the recognition and differentiation of underlying neurodevelopmental characteristics of autism spectrum disorder. Considering the limited available evidence, practical guidance is offered to assist clinicians in their decision-making when a strong evidence base is lacking. In the context of early psychosis, diagnostic formulation should be considered provisional, with assessment of a possible a missed ASD diagnosis occurring after the stabilisation of psychotic symptoms wherever possible.