Autism Spectrum Disorder (ASD) has been studied mainly in children. However, currently, 1/68 adults live with this neurodevelopmental disorder. ASD in adulthood shows suggestive symptoms of cognitive impairment, quickly compromising various cognitive functions. Cognitive impairment and behavioral disorders help to develop neurodegenerative diseases such as Frontotemporal dementia (FTD) and Alzheimer’s Disease (AD) in people with ASD during adulthood, which affects activities of daily living (ADL). The objective of this systematic review is to investigate the progression of ASD to cognitive impairment and dementia in adulthood. The methodology included the qualitative analysis of studies published in the years 2000 and 2020, exclusively in english. Results reveal that adults with ASD develop early cognitive impairment and dementia according to the general population, mainly affecting cognitive functions such as memory and executive functions. In conclusion, moderate to a profound degree of intellectual disability, as well as reductions in white matter, seems to be precursors for the development of cognitive impairment and dementia in adults with ASD.
