Cognitive tests that best discriminate between presymptomatic AD and thosewho remain nondemented

Objective: To identify the most accurate cognitive measures in discriminati ng between individuals with presymptomatic AD and individuals who remained nondemented. Methods: During a 10-year prospective community study, 120 non demented subjects completed a battery of standard cognitive tests and clini cally manifested AD 1.5 years later. Performance on each of 16 cognitive te sts was compared between these 120 presymptomatic cases and 483 controls wh o remained nondemented over the 10-year follow-up period. The area under th e receiver operating characteristic (AUC) curve for each test was used to m easure its accuracy of discrimination between cases and controls. Results: Among the 16 neuropsychological tests, Word List Delayed Recall discriminat ed best between cases and controls (AUC = 0.806), followed by the Word List 3rd Learning Trial (0.787), Word List Ist Learning Trial (0.774), and Trai l-making Test B (0.773), compared to the Mini-Mental State Examination (MMS E) (0.726). Both Word List Delayed Recall and Word List 3rd Learning Trial were significantly more accurate than the MMSE. The combination of Word Lis t Delayed Recall and Trail-making Test B comprised the optimal set of cogni tive measures, with the highest AUC (0.852). Conclusion: Measures of delaye d recall and executive functions were the best discriminators between those who would manifest AD 1.5 years later and those who would remain nondement ed. These findings are relevant for the early detection of AD and, therefor e, for prevention and early intervention trials. Executive dysfunction may be a subtle manifestation of incipient AD, along with memory dysfunction.