Fig. 2

a Prevalence of elevated amyloid levels (A+) versus vascular disease (V+) in clinically unimpaired individuals based on data from Vemuri and Knopman [11]. Vascular pathologies show a steady increase in the prevalence (exponential growth curve models) but the amyloid positivity curves exhibit a slow saturation similar to logistic growth curve models. b Data from our previous study [25] illustrates the slow longitudinal cognitive decline seen in a clinically unimpaired 80-year-old male without amyloid and cerebrovascular pathologies (in blue) in comparison with significantly greater decline seen in a clinically unimpaired individual of the same age with both elevated amyloid and cerebrovascular pathologies (in red)