Associations between remote cognitive testing on an individual’s own digital device and amyloid burden on neuroimaging in clinically normal older adults: Results from Boston Remote Assessment for Neurocognitive Health (BRANCH)

Abstract

AbstractBackgroundDigital cognitive testing completed on an individual’s own device, independently, and remotely is a highly appealing solution to sensitively capture early memory changes in preclinical AD. However, few digital assessments have been designed specifically for a preclinical AD population and validated against paper‐and‐pencil measures and relevant AD biomarkers. Here, we describe initial validation steps for the Boston Remote Assessment of Neurocognitive Health (BRANCH), web‐based cognitive testing targeting cognitive domains with AD susceptibility (e.g., cross‐modal associative memory, semantically facilitated learning and recall, and pattern separation) and using task stimuli relevant to everyday life. To determine the validity of BRANCH, we explored correlations between remote BRANCH to in‐clinic paper and pencil measures and PET amyloid burden.MethodA link to BRANCH was either texted or emailed to 128 clinically normal (CN) older adults participating in the Harvard Aging Brain Study. Participants completed the 4 BRANCH measures (modified Face Name Test, groceries test, categories test, signs test) over a mean 19 minutes. Participants had previously completed in‐clinic paper and pencil tests to compute a Preclinical Alzheimer’s Cognitive Composite (PACC‐5) as well as PET imaging with 11CPittsburg Compound‐B to estimate global amyloid burden. A composite of accuracy across BRANCH tasks was computed.ResultParticipants had a mean age of 74.38(Range 51‐89), were 82% Caucasian, and 60.7% female. They completed BRANCH on smartphones (26%), tablets (18%), laptops (26%), and desktops(29%). Only 2.59% of participants reported difficulty completing BRANCH on a post‐test survey. Lower BRANCH composite performance was associated with worse performance on in‐person paper and pencil measures (Figure 1; PACC; r=0.637, p<0.001). Lower BRANCH performance was associated with greater amyloid burden (r=‐0.275, p=0.003).ConclusionA digital memory assessment with ecologically‐valid tasks and stimuli is feasible for CN older adults to complete independently on their own devices. The relatively strong correlation observed between BRANCH and PACC suggests that BRANCH captures valid information about cognitive performance despite being collected remotely on an individual’s own device. The significant association between BRANCH and amyloid burden suggests that these remotely captured tasks may be promising tools to detect and track AD‐specific cognitive decrements on a larger scale.