Exploring language performance in people with mild cognitive impairment and Alzheimer's disease: a prospective longitudinal study

Background/Aims Language changes are the earliest signs and symptoms of mild cognitive impairment and Alzheimer's disease. The aim of this study was to explore the language difference performance between people with mild cognitive impairment, people with Alzheimer's disease and healthy individuals as a control group. To accomplish this aim, the language profile of both mild cognitive impairment and Alzheimer's disease needs to be characterised to determine which feature is more affected by both mild cognitive impairment and Alzheimer's disease among expressive language, receptive language, executive function and memory performance. Methods This case-control prospective study involved 90 participants. The Mini-Mental Status Examination and the Functional Assessment Staging Tool were used to classify the participants into three groups: people with mild cognitive impairment, people with Alzheimer's disease and healthy individuals as a control group. Then, the language performance of patients in the mild cognitive impairment and Alzheimer's disease groups was investigated and compared with those of the control group by using the Barnes Language Assessment. The groups were reassessed 6 months later to see if there was any change in language ability. Results The results showed that the mild cognitive impairment group and Alzheimer's disease group had significant decreases in expressive language (P>0.01), executive function (P>0.01), receptive language (P>0.01) and memory skills (P>0.01) from baseline to the reassessment at 6 months. Conclusions Language deficits, especially expressive language deficits, could appear before impairment in executive function, receptive language and verbal episodic memory in participants with mild cognitive impairment or Alzheimer's disease. Speech and language therapists can use the findings of this study to design and implement treatment programmes.