A COMPARISON OF SEMANTIC MEMORY IN VASCULAR DEMENTIA AND DEMENTIA OF ALZHEIMERS TYPE

Objective. To determine whether semantic memory is impaired in vascula r dementia and to assess the utility of semantic memory measures in di fferentiating vascular dementia from dementia of Alzheimer's type (DAT ). Design. Case-control study. Patients. Ten patients with Cambridge M ental Disorders in the Elderly (CAMDEX) diagnosis of 'definite' mild o r moderate vascular dementia (mean age 77) were individually matched w ith 10 patients with a CAMDEX diagnosis of 'definite' DAT on the basis of age, education, sex, premorbid IQ (as measured by the National Adu lt Reading Test) and performance on the Cambridge Cognitive Examinatio n (CAMCOG) In addition, 10 age, sex and education matched volunteer or relative controls were assessed. Outcome measures. A detailed semanti c memory test battery consisting of five subtests: category fluency, p icture naming, picture sorting, word-picture matching and generation o f verbal definitions. Results. Compared to normal controls, both patie nt groups were impaired on all subtests of the semantic battery with t he exception of the word-picture matching test. No differences were fo und between the vascular dementia and DAT groups on any of the measure s. Conclusions. Impairment of semantic memory is a feature of both vas cular dementia and DAT. Tests of semantic memory appear, therefore, of little value in differentiating between these two major causes of dem entia. Further work is required to determine whether the nature of the processing deficit is the same in these conditions. (C) 1997 by John Wiley & Sons, Ltd.