Clinical features of behavioral symptoms in patients with semantic dementia: Does semantic dementia cause autistic traits?

Objective To investigate the behavioral characteristics of semantic dementia (SD) using an instrument originally developed for patients with autism spectrum disorder. Methods The symptoms 20 SD and Alzheimer’s disease (AD) in both preclinical state were evaluated Pervasive Developmental Disorders Autism Society Japan Rating Scale (PARS). Results group showed high prevalence four behaviors related to stereotypy social impairment: eating very few food items, selfishness, difficulty recognizing others’ feeling thoughts, interpreting language literally. Scores on PARS short version, which is sensitive diagnosis disorder, significantly higher than (11.5 ± 6.0 1.7 2.5, respectively; t (19) = 6.7, p < 0.001) AD (6.9 4.6 2.0, 5.1, groups. version scores after onset increased groups, although increase was larger (F 5.6, 0.023). Additionally, a rate exceeded cutoff score (75%) (40%; χ 2 5.0, 0.025). correlated illness duration (r 0.46, 0.04) Mini-Mental State Examination −0.75, only. Conclusions Although disorder are etiologically distinct diseases, behave like those Our findings suggest symptomatic similarity two disorders.