Cognitive performance on the Alzheimer's Disease Assessment Scale: effect of education

• Published in: Neurology Vol. 45; no. 11; p. 1980
• Main Authors: Doraiswamy, P M, Krishen, A, Stallone, F, Martin, W L, Potts, N L, Metz, A, DeVeaugh-Geiss, J
• Format: Journal Article
• Language: English
• Published: United States 01.11.1995
• Subjects: Aged; Aged, 80 and over; Alzheimer Disease - physiopathology; Alzheimer Disease - psychology; Cognition Disorders - physiopathology; Cognition Disorders - psychology; Educational Status; Female; Humans; Male; Middle Aged; Neuropsychological Tests
• ISSN: 0028-3878
• DOI: 10.1212/WNL.45.11.1980

The cognitive subscale of the Alzheimer's Disease Assessment Scale (ADAS-Cog) is used to monitor disease progression and treatment efficacy in clinical trials of Alzheimer's disease (AD). Using data from a 12-week drug trial, we retrospectively studied the effect of education on ADAS-Cog performance in a group of 444 patients with AD. The effect of education was statistically significant on baseline ADAS-Cog total scores. This effect remained statistically significant after controlling for age, gender, and dementia severity. Education effects were also statistically significant at week 12 for ADAS-Cog total and 10 of 11 subitem scores in 138 AD patients in the placebo arm of the trial. Post hoc analysis showed that non-high school graduates performed worse than those with greater educational levels across a broad range of cognitive domains. Our results, in conjunction with reports linking lower educational level with a higher risk for AD, suggest that educational level of patients be given consideration in the design and interpretation of cognitive tests in AD drug trials.