A-05 The Latin American Spanish Version of the Face-Name Associative Memory Exam is Sensitive to Cognitive and Pathological Changes in Preclinical Autosomal Dominant Alzheimer’s Disease

Objective

To determine whether performance on the Latin American Spanish version of the Face-Name Associative Memory Exam (LAS-FNAME) can differentiate between cognitively intact carriers of an autosomal dominant Alzheimer’s disease mutation (E280A) in Presenilin-1, who are destined to develop early-onset dementia, from matched non-carriers. We also sought to examine whether LAS-FNAME performance is associated with amyloid-β and regional tau burden in mutation carriers.

Methods

35 cognitively intact mutation carriers (age range 26–41), 48 matched non-carriers (aged 27 to 44), and 19 symptomatic carriers (13 with subjective cognitive concerns, 6 with mild cognitive impairment [MCI]) completed the LAS-FNAME. A subset of participants (31 carriers [12 symptomatic] and 35 non-carriers) traveled from Colombia to Boston to undergo positron emission tomography (PET) using Pittsburgh compound B to measure mean cortical amyloid-β and Flortaucipir for regional tau tangles. ANOVA analyses and Spearman correlations were used to examine group differences and relationships among LAS-FNAME performance, Aβ and tau accumulation.

Results

Compared to non-carriers, cognitively intact carriers had lower scores on the LAS-FNAME total scores (p = .040). Across all carriers (including symptomatic carriers), higher levels of amyloid-β (r = −.436, p = .018) and regional tau in the entorhinal (r = −.394, p = .031) and inferior temporal cortex (r = −.563, p = .001) were associated with lower LAS-FNAME total scores (see Figure).

Conclusions

Performance on the LAS-FNAME differentiated between cognitively intact mutation carriers from non-carriers, and was associated with greater amyloid and tau burden when examining all carriers. Findings suggest that the LAS-FNAME is sensitive to early clinical and pathological changes and can potentially help track disease progression in Spanish-speaking individuals.

Biological and Cognitive Markers of Presenilin1 E280A Autosomal Dominant Alzheimer's Disease: A Comprehensive Review of the Colombian Kindred

The study of individuals with autosomal dominant Alzheimer's disease affords one of the best opportunities to characterize the biological and cognitive changes of Alzheimer's disease that occur over the course of the preclinical and symptomatic stages. Unifying the knowledge gained from the past three decades of research in the world's largest single-mutation autosomal dominant Alzheimer's disease kindred - a family in Antioquia, Colombia with the E280A mutation in the Presenilin1 gene - will provide new directions for Alzheimer's research and a framework for generalizing the findings from this cohort to the more common sporadic form of Alzheimer's disease. As this specific mutation is virtually 100% penetrant for the development of the disease by midlife, we use a previously defined median age of onset for mild cognitive impairment for this cohort to examine the trajectory of the biological and cognitive markers of the disease as a function of the carriers' estimated years to clinical onset. Studies from this cohort suggest that structural and functional brain abnormalities - such as cortical thinning and hyperactivation in memory networks - as well as differences in biofluid and in vivo measurements of Alzheimer's-related pathological proteins distinguish Presenilin1 E280A mutation carriers from non-carriers as early as childhood, or approximately three decades before the median age of onset of clinical symptoms. We conclude our review with discussion on future directions for Alzheimer's disease research, with specific emphasis on ways to design studies that compare the generalizability of research in autosomal dominant Alzheimer's disease to the larger sporadic Alzheimer's disease population.