A comparison of word‐list and story recall tests for prediction of biomarker‐determined Alzheimer’s disease

Abstract

AbstractBackgroundWord‐list and story recall tests are routinely employed in clinical practice for dementia screening. Previous research has shown that both types of tests are predictive of subsequent clinical diagnoses of dementia, including when examining process scores such as forgetting rate. In this study, our aim was to establish how well standard clinical metrics compared to process scores derived from word‐list and story recall tests in predicting biomarker‐determined Alzheimer’s disease (bdAD), as defined by CSF p‐tau/Abeta42 ratio.MethodData from 381 participants (mean age = 65, ± 9) were drawn from the University of Wisconsin – Madison Alzheimer’s Disease Research Center (ADRC) and Wisconsin Registry for Alzheimer’s Prevention (WRAP). Rey’s Auditory Verbal Learning Test (AVLT; word‐list) and Logical Memory Test (LMT; story) data were available. The conventional clinical scores examined were: AVLT total recall, AVLT delayed recall, LMT immediate recall, and LMT delayed recall. The process scores examined were: AVLT recency ratio (i.e., recency forgetting), AVLT total forgetting, LMT recency ratio, LMT total forgetting, and LMT primacy ratio (i.e., primacy forgetting). Bayesian linear regression analyses were carried out with either the nearest or farthest CSF p‐tau/Abeta42 ratio as outcome; the standard and process baseline memory scores as predictors; and baseline age, time elapsed from baseline to lumbar puncture, APOE risk score, sex, and years of education as control variables. Sensitivity analyses were carried out with logistic regressions using a cut‐off of 0.038 CSF p‐tau/Abeta42 ratio as outcome, to assess diagnosticity. CSF biomarkers were measured using the NeuroToolKit (Roche Diagnostics International Ltd, Rotkreuz, Switzerland).ResultLMT recency ratio and LMT primacy ratio were the best performing predictors (BF10 > 1 billion) both when evaluating the nearest (Figure 1a) and the farthest (Figure 1b) outcomes. However, sensitivity analyses with a binary cut‐off favored the primacy ratio. Areas under the curve (AUCs) ranged from 0.86 to 0.87 (including covariates). Specificity was consistently high for primacy ratio with 94% probability of correctly identifying individuals without bdAD.ConclusionOur study shows that story recall tests may be better than word‐list tests for dementia screening, especially when employing process scores alongside conventional clinical scores.