Unsupervised mobile cognitive testing for use in preclinical Alzheimer's disease

Area of Science:

• Neuroscience
• Digital Health
• Biomarkers

Background:

• Subtle cognitive decline in preclinical Alzheimer's disease (AD) is challenging to detect.
• Unsupervised digital cognitive testing offers a promising avenue for early AD detection.
• The Boston Remote Assessment for Neurocognitive Health (BRANCH) was developed to address this need.

Purpose of the Study:

• To describe the development, feasibility, and validity of the BRANCH digital cognitive assessment.
• To evaluate BRANCH's performance against in-person cognitive testing.
• To assess the association between BRANCH scores and Alzheimer's disease biomarkers (amyloid and tau).

Main Methods:

• BRANCH is a web-based, self-guided assessment evaluating memory processes vulnerable in AD.
• 234 clinically normal participants (aged 50-89) completed BRANCH on personal devices.
• A subset underwent in-person cognitive testing and positron emission tomography (PET) imaging.

Main Results:

• BRANCH demonstrated feasibility and infrequent technical issues, with sound psychometric properties and good retest reliability.
• BRANCH scores correlated significantly with in-person cognitive testing (r = 0.617, P < .001).
• Lower BRANCH scores were associated with higher amyloid burden (r = -0.205, P = .007) and entorhinal tau (r = -0.178, P = .026).

Conclusions:

• BRANCH reliably captures meaningful cognitive data remotely.
• The digital assessment shows promise as a sensitive marker for early AD detection.
• BRANCH may aid in identifying individuals in the preclinical stages of Alzheimer's disease.