Sequence of decline on the NIH-toolbox cognitive battery in a predominantly Latino sample with autosomal dominant Alzheimer's disease.

Background: Understanding the sequential progression of cognitive decline in autosomal dominant Alzheimer's disease (ADAD) in the Latino population is crucial for enhancing early identification for targeted interventions. Given the tablet-based administration and increasing frequency of use in epidemiological research, validating this progression within the NIH Toolbox cognitive battery (NIHTB-CB) is important.

Objective: The first aim was to utilize an innovative Event-Based Modeling (EBM) analytic approach to estimate the sequence of cognitive declines in persons at risk for ADAD enriched for being of Latino origin. The second aim was to examine associations between EBM-derived estimates of cognitive disease severity and independent cognitive outcomes within carriers and noncarriers.

Methods: This cross-sectional observational study (N = 30) included 16 ADAD mutation carriers and 14 noncarriers who completed the NIHTB-CB in their primary language (n = 8 Spanish; n = 22 English). An EBM was constructed to compare ADAD mutation carriers and noncarriers on NIHTB-CB performance. We utilized linear regression to examine the associations between the EBM-derived cognitive-decline disease stage and independent outcomes (e.g., performance on the Cognitive Abilities Screening Instrument (CASI) and estimated years to dementia diagnosis).

Results: The EBM estimated that tests assessing episodic memory were the first to become abnormal in the sequence of ADAD-related cognitive decline. Each higher estimated cognitive-decline disease stage was associated with approximately a three-point decline in the CASI and two years closer to dementia diagnosis.

Conclusions: Findings support the EBM applied to the tablet-based NIHTB-CB to estimate the likely progression of cognitive decline in Latinos with ADAD.