Introduction: We aimed to define a Mayo Preclinical Alzheimer's disease Cognitive Composite (Mayo-PACC) that prioritizes parsimony and use of public domain measures to facilitate clinical translation.
Methods: Cognitively unimpaired participants aged 65 to 85 at baseline with amyloid PET imaging were included, yielding 428 amyloid negative (A-) and 186 amyloid positive (A+) individuals with 7 years mean follow-up. Sensitivity to amyloid-related cognitive decline was examined using slope estimates derived from linear mixed models (difference in annualized change across A+ and A- groups). We compared differences in rates of change between Mayo-PACC and other composites (A+ > A- indicating more significant decline in A+).
Results: All composites showed sensitivity to amyloid-related longitudinal cognitive decline (A+ > A- annualized change p < 0.05). Comparisons revealed that Mayo-PACC (AVLT sum of trials 1-5+6+delay, Trails B, animal fluency) showed comparable longitudinal sensitivity to other composites.
Discussion: Mayo-PACC performs similarly to other composites and can be directly translated to the clinic.
Keywords: ADCS-PACC; PACC-R; aging; amyloid; biomarker; cognitive decline; cognitive outcome measure; embedded pragmatic clinical trials; global cognition; longitudinal; neuropsychology; practice effect; reliability; validity.
© 2022 Mayo Foundation for Medical Education and Research. Alzheimer's & Dementia published by Wiley Periodicals LLC on behalf of Alzheimer's Association.