Screening for predementia AD: time-dependent operating characteristics of episodic memory tests

Data from the Einstein Aging Study (EAS) were used to prospectively evaluate the free recall score from the free and cued selective reminding test (FCSRT-FR) and logical memory I immediate recall (LM-IR) subtest of the Wechsler memory scale-revised for prediction of incident Alzheimer disease (AD) dementia among individuals from a community-based cohort with memory complaints.

Analyses included 854 participants, age ≥70 years, who initially had no dementia, and had memory complaints. Clinic evaluations were completed annually and AD dementia was diagnosed using standard criteria (n = 86 cases; average follow-up 4.1 years). Time-dependent receiver operating characteristic analysis was used to evaluate the prognostic ability of FCSRT-FR and LM-IR for incident AD over various durations of follow-up.

For identifying those with memory complaints who will develop incident AD dementia over 2-4 years, the FCSRT-FR had better operating characteristics than LM-IR. APOE ε4 status, age, and education did not affect cut points; however, positive predictive values were higher among APOE ε4-positive individuals.

For follow-up intervals of 2-4 years, the FCSRT-FR is more predictive than the LM-IR for identifying individuals with memory complaints who will develop incident AD. APOE ε4 status improves positive predictive value, but does not affect the choice of optimal cuts.