B - 114 Evaluation of the Montreal Cognitive Assessment Memory Index Score for Predicting Amnestic Mild Cognitive Impairment to Alzheimer’s Clinical Syndrome Progression

Abstract Objective The Montreal Cognitive Assessment Memory Index Score (MoCA-MIS) is derived from the MoCA as a supplementary memory measure, with research suggesting the MoCA-MIS can identify those at higher risk of progression from mild cognitive impairment (MCI) to Alzheimer’s Clinical Syndrome (ACS). This study evaluated the sensitivity and specificity of the MoCA total score (TS), delayed free recall score (DFRS), and MIS in classifying amnestic MCI (aMCI) to ACS converters and replicated an algorithm recommended by Julayanont et al. (2014). Methods National Alzheimer’s Coordinating Center data were examined in individuals with aMCI, ≥50 years of age (Myears = 75.35[7.92]) who had 3–6 annual follow-up visits. Participants (n = 353) were mostly male (58%), White (88%), and well-educated (Myears = 16.37[5.21]). Receiver operating characteristic (ROC) analyses utilized baseline MoCA scores to examine optimal cutoffs using Youden’s index. Sensitivity and specificity of Julayanont’s algorithm (TScutoff<20 + MIScutoff<7) were also examined. Results Over follow-up (Myears = 4.52[1.02]), 53.3% converted to ACS. ROC analyses to predict longitudinal conversion from aMCI to ACS revealed similar sensitivity and specificity across MoCA scores (TScutoff<24, AUC = 0.67, Sensitivity = 0.78, Specificity = 0.49; DFRScutoff<2, AUC = 0.67, Sensitivity = 0.75, Specificity = 0.54; MIScutoff<8, AUC = 0.69, Sensitivity = 0.66, Specificity = 0.64). The Julayanont algorithm displayed low sensitivity (0.18) but high specificity (0.93) in this sample. Conclusion In predicting aMCI to ACS conversion over a 3–6 year period, baseline MoCA-TS, DFRS, and MIS cutoffs failed to demonstrate high sensitivity with adequate specificity. The Julayanont combination approach had unacceptable sensitivity in this sample. These findings suggest MoCA cutoffs are poor predictors of future cognitive progression in those with aMCI and highlight the importance of comprehensive longitudinal follow-up.