The cognitive subscale of the "Alzheimer's Disease Assessment Scale" in a Brazilian sample

The cognitive subscale of the "Alzheimer's Disease Assessment Scale" (ADAS- Cog) is widely used for tile evaluation of dementia and is very popular in dementia drug trials because of the characteristics of the scale. The objec tive of the present study was to adapt the ADAS-Cog for use for the Brazili an population. A major problem is that education is variable, a fact that m ay influence performance in cognitive evaluation. This study was conducted on a control group (CG) of 96 subjects (25 males and 71 females aged 68 +/- 8.6 years) and on 44 Alzheimer's disease (AD) patients (19 males and 25 fe males aged 72 +/- 6.4 years) with mild dementia (Clinical Dementia Rating s core 1). For statistical analysis groups were divided into three educationa l levels: I, 0-4 years of schooling (65 CG/20 AD) II, 5-11 years of schooli ng (19 CG/7 AD), and III, 12 or more years of schooling (12 CG/17 AD). The battery was applied according to original instructions. Total mean score fo r CG and AD was 10.9 and 22.9 for level I, 7.8 and 22.4 for level II, and 6 .2 and 15.4 for level III, respectively. These results indicate that our ve rsion of the ADAS-Cog is useful to identify mild dementia, though there may be an overlapping when comparing high education demented with low educatio n non-demented subjects.