Fig. 1: Atrophy at population level in the CU and AD groups.

For the calculation of cognitively unimpaired (CU) and Alzheimer’s disease (AD) atrophy patterns at the different ages (A, B), the data were z value transformed. One mixed effect multivariate model was used to visualize the differences in atrophy between the two diagnostic labels (red color; more atrophy, yellow color; less atrophy). The upper right color legend refers to standard deviations from the sample mean (0 corresponds to the mean of AD and CU sample values). At 55 years of age, AD has seemingly similar atrophy levels to the CU population and differences show up with ageing. For the visualization of the AD data correction based on the CU sample (C), two separate mixed effect multivariate models (one for the CU sample and one for the AD sample) were used. The AD data were standardized based on the CU data. Thus, the lower color legend shows standard deviations of the AD population below the CU population (w-values, 0 corresponds to the mean of CU sample values). Younger AD patients (between 55 and 65 years of age) show more posterior atrophy compared to controls, while older AD patients (above 75 years old) show more mediotemporal and hippocampal atrophy compared to controls. For the visualization models the fitted values in panels A, B, and C are controlled for MRI field strength, cohort.