Sentence composition ability in two patients with non-fluent/agrammatic variant primary progressive aphasia

Agrammatism is one of the core clinical features of non-fluent/agrammatic variant primary progressive aphasia, and it has traditionally been considered the hallmark of non-fluent aphasia in Western countries. However, agrammatic speech may remain undetected in Japanese patients because of the agglutinative structure of the language and high flexibility in word order. In the present study, we aimed to analyze agrammatism in the speech production of Japanese patients with aphasia due to neurodegenerative disease using an anagram test generated by our laboratory. Four patients were recruited from the dementia clinic at Tohoku University Hospital between December 2014 and August 2015: two patients with non-fluent/agrammatic variant primary progressive aphasia, one with semantic variant primary progressive aphasia, and one with probable Alzheimer's disease experiencing episodic memory impairment accompanied by transcortical sensory aphasia. All patients underwent thorough neurological and neuropsychological testing before performing a Japanese anagram task based on the Northwestern Anagram Test. Our findings indicated that the two patients with non-fluent/agrammatic variant primary progressive aphasia exhibited poorer performance on the anagram task than the remaining two patients. Therefore, the anagram test used in the present study may aid in detecting output aspects of agrammatism in Japanese patients with aphasia, although future studies are required to develop a standardized version of test.