Behaviors characteristic of Autism spectrum disorder in a geriatric cohort with mild cognitive impairment or early dementia

Autism spectrum disorder (ASD) represents a heterogeneous cluster of clinical phenotypes that are classically diagnosed by the time of adolescence. The possibility of late-life emergence of ASD has been poorly explored. In order to more fully characterize the possibility of late-life emergence of behaviors characteristic of ASD in MCI and AD, we surveyed caregivers of 142 older persons with cognitive impairment from the University of Kentucky Alzheimer’s Disease Center Longitudinal Cohort using the Gilliam Autism Rating Scale-2. Participants with high autism index ratings (Autism ‘Possible/Very Likely’, n=23) reported significantly (statistically and clinically) younger age at onset of cognitive impairment than those who scored in the Autism ‘Unlikely’ range (n=119): 71.14±10.9 vs. 76.65±8.25 (p = 0.034). Additionally, those in Autism ‘Possible/Very Likely’ group demonstrated advanced severity of cognitive impairment, indicated by Clinical Dementia Rating Scale Sum of Boxes scores. Data demonstrate that ASD behaviors may appear de novo of degenerative dementia and such behaviors are more prevalent in those with early onset dementia. Further work elucidating a connection between ASD and dementia could shed light on subclinical forms of ASD, identify areas of shared neuroanatomic involvement between ASD and dementias, and provide valuable insights that might hasten the development of therapeutic strategies.

Source: Rhodus EK, Barber J, Abner EL, Duff DMC, Bardach SH, Caban-Holt A, Lightner D, Rowles GD, Schmitt FA, Jicha GA. Behaviors Characteristic of Autism Spectrum Disorder in a Geriatric Cohort With Mild Cognitive Impairment or Early Dementia. Alzheimer Dis Assoc Disord. 2020 Jan-Mar;34(1):66-71. doi: 10.1097/WAD.0000000000000345. PMID: 31517641; PMCID: PMC7047536.