Smartphone-based detection of memory decline in prodromal Alzheimer’s disease

The slow progression of Alzheimer’s disease (AD) poses a challenge for the rapid and individual quantification of early disease-driven cognitive decline. Here, we show that frequently administered remote and unsupervised digital cognitive assessments can detect cognitive decline within 30 weeks in early AD. The sample comprised 202 individuals (52–85 years old), who were cognitively unimpaired (CU) or had mild cognitive impairment (MCI). Participants self-administered remote tasks testing object and scene memory precision, associative memory, and familiarity-dependent memory. A short-term decline in the familiarity-dependent task was observed in all patients with an MCI diagnosis, while both the familiarity-dependent task and memory precision for objects were sensitive to decline in amyloid-positive MCI patients specifically. Change in the remote familiarity-dependent task was correlated with multi-year change on annual in-person neuropsychological assessments. In conclusion, frequent remote cognitive testing is a promising tool to feasibly capture and monitor subtle and short-term cognitive decline.