Screening for frontotemporal dementias and Alzheimer's disease with the Philadelphia Brief Assessment of Cognition: a preliminary analysis.

BACKGROUND A neuropsychological screening instrument sensitive to neuropsychological deficits associated with Alzheimer's disease (AD) and patients with frontotemporal dementia (FTD) would be valuable for diagnostic evaluation. METHODS The Philadelphia Brief Assessment of Cognition (PBAC) assesses working memory/executive control, language, visuospatial operations, verbal/visual episodic memory, and behavior/social comportment and can be administered and scored in 15-20 min. Participants included 149 patients with AD and four groups of FTD patients - i.e., patients with a decline in social comportment, personality, and executive functioning (SOC/EXEC), semantic dementia (SemD), progressive nonfluent aphasia (PNFA), and corticobasal syndrome (CBS). RESULTS The total PBAC score correlated with the Mini-Mental State Examination. Between-group analysis of PBAC subscales and the results of logistic regression analyses produced substantial between-group differences, emphasizing the sensitivity of the test to differentiate dementia subtypes. AD patients were impaired on tests of episodic memory, SOC/EXEC patients were impaired on a measure of social comportment/behavioral disturbance, PNFA patients obtained low scores on tests of working memory/executive control, SemD patients obtained lower scores on language-mediated measures, and CBS patients were impaired on visuospatial/visual memory tests. CONCLUSION These data support the usefulness of the PBAC as a relatively brief screening test of overall dementia severity across a wide range of dementia patients.