Comparative study of aprosody in Alzheimer's disease and in multi-infarct dementia

Prosody is defined as the melodic line of language. In this study we included 25 patients with probable Alzheimer's disease and 14 with multi-infarct dementia for a comparative cross-sectional study of prosody. Neuropsychological analysis was based on Mini-Mental test, Blessed Scale and Clinical Dementia Rating. We used the criteria of Monrad-Krohn to evaluate prosodic categories. We found intrinsic aprosody in 8 patients with Alzheimer's disease and in none of the patients with multi-infarct dementia (prevalence ratio: 1.82, 95% CI: 1.32-2.51), and emotional aprosody in 17 patients with Alzheimer's disease in comparison to 4 with multi-infarct dementia (prevalence ratio: 1.8, 95% CI: 1.04-3.18). The differences in intellectual and inarticulate aprosody were not significant. We conclude that aprosody is more frequent and severe in Alzheimer's disease than in multi-infarct dementia.