Autism spectrum disorder: has it lost its meaning and is it leading to misdiagnosis?

Key Points:

• The diagnostic criteria for autism have evolved significantly since its first inclusion in DSM-III (1980), with the latest DSM-V (2013/2022) consolidating previous subtypes into a single autism spectrum disorder (ASD) diagnosis, broadening the criteria and lowering the diagnostic threshold.
• The dramatic rise in ASD prevalence, from 0.04% in the 1960s to around 1.8-2% today in the UK and globally, is uneven across age groups and sexes, largely driven by increased diagnoses in females and individuals diagnosed after childhood, suggesting the existence of distinct subgroups within the spectrum.
• Recent genetic and population studies indicate a split in the autism spectrum between early-diagnosed individuals, characterized by core autism features and intellectual disability, and later-diagnosed individuals, who show stronger genetic ties to other psychiatric conditions like ADHD and depression, raising concerns about potential misclassification.
• Cultural factors such as inclusiveness, social contagion, self-diagnosis trends, and the rise of neurodiversity have influenced the broadening of the autism concept, while the tension between the social and medical models of disability complicates the understanding and acceptance of autism as either a difference or a disorder.
• To improve diagnostic precision and support, experts advocate for splitting the broad autism spectrum into more specific subgroups, enabling tailored interventions and preventing misdiagnosis, particularly to better address the needs of late-diagnosed individuals and those with severe impairments.