Journal of the International Neuropsychological Society



Amnestic mild cognitive impairment: Diagnostic outcomes and clinical prediction over a two-year time period


H. RANDALL  GRIFFITH  a1 a2 c1 , KELLI L.  NETSON  a3 , LINDY E.  HARRELL  a1 a2 , EDWARD Y.  ZAMRINI  a1 a2 , JOHN C.  BROCKINGTON  a1 a2 and DANIEL C.  MARSON  a1 a2
a1 Department of Neurology, University of Alabama at Birmingham, Birmingham, Alabama
a2 Alzheimer's Disease Research Center, University of Alabama at Birmingham, Birmingham, Alabama
a3 Department of Psychology, University of Alabama at Birmingham, Birmingham, Alabama

Article author query
griffith hr   [PubMed][Google Scholar] 
netson kl   [PubMed][Google Scholar] 
harrell le   [PubMed][Google Scholar] 
zamrini ey   [PubMed][Google Scholar] 
brockington jc   [PubMed][Google Scholar] 
marson dc   [PubMed][Google Scholar] 

Abstract

Amnestic mild cognitive impairment (MCI) has been defined as a precursor to Alzheimer's disease (AD), although it is sometimes difficult to identify which persons with MCI will eventually convert to AD. We sought to predict MCI conversion to AD over a two-year follow-up period using baseline demographic and neuropsychological test data from 49 MCI patients. Using a stepwise discriminant function analysis with Dementia Rating Scale (DRS) Initiation/Perseveration and Wechsler Memory Scale, third edition (WMS-III) Visual Reproduction Percent Retention scores, we correctly classified 85.7% of the sample as either AD converters or MCI nonconverters, with 76.9% sensitivity and 88.9% specificity. Adding race, the presence of vascular risk factors, or cholinesterase inhibitor use to the analysis did not greatly change the classification rates obtained with neuropsychological test data. Examining neuropsychological test cutoff scores revealed that DRS Initiation/Perseveration scores below 37 and Visual Reproduction Percent Retention scores below 26% correctly identified AD converters with 76.9% sensitivity and 91.7% specificity. These results demonstrate that commonly administered neuropsychological tests identify persons with MCI at baseline who are at risk for conversion to AD within 1–2 years. Such methods could aid in identifying MCI patients who might benefit from early treatment, in providing prognostic information to patients, and identifying potential clinical trial participants. (JINS, 2006, 12, 166–175.)

(Received April 18 2005)
(Revised November 3 2005)
(Accepted November 30 2005)


Key Words: Neuropsychology; Alzheimer's disease; Memory; Psychomotor performance; Dementia; Demography.

Correspondence:
c1 Reprint requests to: Dr. H. Randall Griffith, Department of Neurology, University of Alabama at Birmingham, 1216 Jefferson Tower, 625 19th Street South, Birmingham, AL. E-mail: rlgriffith@uabmc.edu


Related Content