Prevalence of symptoms on the CERAD behavior rating scale for dementia in normal elderly subjects and Alzheimer's disease patients

The authors sought to define "abnormal" levels for total scores on the CERA D Behavioral Rating Scale for Dementia (BRSD) and for 37 BRSD items by comp aring 242 patients with Alzheimer's disease (AD) and 64 normal elderly cont rol subjects (NEC). BRSD total scores for NEC ranged as high as 52 (out of a maximum 167), and although item prevalence rates were higher for AD patie nts, not all of these differences were significant. Many symptoms were obse rved in less than or equal to 10% of AD subjects. Lower Mini-Mental State E xamination scores were not consistently associated with lower or higher lev els of endorsement across all items. Over 6 and 12 months, endorsement rate s were relatively stable for both groups. The authors conclude that assessm ent of behavior in long-term studies will be needed to quantify "abnormal" levels, and that item-level BRSD information could be important in clinical trials.