P2-188: Prediction of cognitive impairment among elderly persons using a brief cognitive screening battery

Abstract

Early detection of cognitive impairment among the elderly is becoming increasingly important. There is a need for brief measures that can reliably predict the presence of clinically significant cognitive impairment. To decipher which brief cognitive tests most reliably predict cognitive impairment, particularly amnestic Mild Cognitive Impairment (aMCI), among elderly persons. Participants aged 70+ with normal baseline cognitive functioning were subsequently administered yearly 30–35 minute cognitive screening batteries, including the Modified Mini Mental State Examination (3MSE), generative verbal fluency (supermarket items), Narratives from the Rivermead Behavioral Memory Test (RBMT), Brief Visuospatial Memory Test, Revised (BVMT–R), Hopkins Verbal Learning Test, Revised (HVLT–R), digit span (DS), and the Geriatric Depression Scale (GDS). When participants' scores on these measures fell below pre–specified cut points, a more expansive dementia evaluation was triggered to assist in diagnosing the presence and extent of cognitive impairment. Scores on the cognitive screening measures were entered into a stepwise logistic regression analysis to predict outcome of the dementia evaluation. The 3MSE, RBMT delay, HVLT–R delay, DS backward, and GDS were identified as significant predictors of normal versus impaired cognitive functioning. However, when participants with normal cognitive functioning were compared only to those with aMCI, the 3MSE and RBMT delay were the only significant predictors. Furthermore, only the 3MSE was identified as a significant predictor of aMCI versus Alzheimer's disease (AD). Brief cognitive screening measures are capable of differentiating between normal and impaired cognitive functioning upon more in–depth cognitive evaluation. The fact that fewer and less diverse measures reliably predicted cognitive impairment when the outcome was narrowed to normal versus aMCI supports the notion that diverse cognitive impairment can result from a variety of factors among the elderly. This finding also highlights the benefit of using certain screening measures to assist in differentiating aMCI from other forms of cognitive impairment. Results of this study further suggest that some measures are not helpful in predicting dementia evaluation outcome. Thus, their utility in triggering a dementia evaluation should be further examined. Overall results of this study have implications for the effective early evaluation and diagnosis of aMCI.