Profiles of cognitive change in preclinical Alzheimer’s disease using change-point analysis

<jats:title>Abstract</jats:title><jats:sec><jats:title>Introduction</jats:title><jats:p>Change-point analyses are increasingly used to identify the temporal stages of accelerated cognitive decline in the preclinical stages of Alzheimer’s Disease (AD). However, statistical comparisons of change-points between specific cognitive measures have not been reported.</jats:p></jats:sec><jats:sec><jats:title>Methods</jats:title><jats:p>165 older adults (baseline age range: 61.1-91.2) from the Baltimore Longitudinal Study of Aging developed AD during follow-up. Linear and non-linear mixed models were fit for 11 cognitive measures to determine change-points in rates of decline before AD diagnosis. Bootstrapping was used to compare the timing of change-points across cognitive measures.</jats:p></jats:sec><jats:sec><jats:title>Results</jats:title><jats:p>Change-points followed by accelerated decline ranged from 15.5 years (Card Rotations) to 1.9 years (Trail-Making A) before AD diagnosis. Accelerated decline in Card Rotations occurred significantly earlier than all other measures, including learning and memory measures.</jats:p></jats:sec><jats:sec><jats:title>Discussion</jats:title><jats:p>Results suggest that visuospatial ability, as assessed by Card Rotations, may have the greatest utility as an early predictive tool in identifying preclinical AD.</jats:p></jats:sec>