Language in Alzheimer's disease

Abstract

Objective: To ascertain the clinical utility of language examination by psychiatrists in evaluating Alzheimer's disease (AD) patients.

Method: Data collected between 1986 and 2003 from a standardized psychiatric examination and neuropsychological testing of probable AD patients (diagnosed according to the criteria of the National Institute of Neurological and Communicative Disorders and Stroke and the Alzheimer's Disease and Related Disorders Association) were gathered from the database of the University of Texas Southwestern Alzheimer's Disease Center, Dallas. The variables studied were articulation, word-finding ability, hypofluency, hyperfluency, repetition, confrontational naming, and semantic (category) fluency. Articulation, word-finding ability, hypofluency, hyperfluency, repetition, and confrontational naming were rated as normal or abnormal. Semantic fluency was scored numerically as the number of animals named in a minute. Cognitive impairment was assessed with the Mini-Mental State Examination (MMSE) and global impairment by the Clinical Dementia Rating (CDR) scale.

Results: There was a significant association (p < .0001) between MMSE and CDR scores for all language measures except hyperfluency. The MMSE scores were higher in the group with responses rated as normal compared to those with abnormal responses. Patients with greater cognitive and global impairment named fewer animals in a minute.

Conclusions: Abnormal articulation and repetition of words were unusual and therefore would not be useful for early detection, but when present, were associated with more advanced disease. Impairment in fluency, animal naming, and confrontational naming were common and increased in frequency with greater cognitive and global impairment. Because animal naming is a numerical measure, changes in the number of animals named in a minute can be used to monitor disease progression.