Table 2.
Demographics of Aβ− and Aβ+ older adults
| Label | Aβ− | Aβ+ | p values |
|---|---|---|---|
| n | 24 | 24 | |
| Age (years) | 74.4 ± 1.15 | 76.8 ± 1.27 | p = 0.18 |
| Gender | 10 ♂ / 14 ♀ | 14 ♂ / 10 ♀ | p = 0.25 |
| APOE4 status | 20 ϵ4− /3 ϵ4+ | 10 ϵ4−/13 ϵ4+ | p = 0.002 |
| Years of education | 16.8 ± 0.59 | 16.9 ± 0.47 | p = 0.91 |
| VIQ | 123.2 ± 1.54 | 123.4 ± 1.16 | p = 0.93 |
| CDR | 0 | 0 | |
| MMSE | 29 ± 0.16 | 29.3 ± 0.18 | p = 0.30 |
| BNT | 28.3 ± 0.47 | 27.9 ± 0.47 | p = 0.52 |
| Memory (d′) | 1.14 ± 0.37 | 1.02 ± 0.27 | p = 0.27 |
| Hippocampal volume (mm3) | 7526 ± 161 | 7518 ± 213 | p = 0.98 |
| Entorhinal thickness (mm) | 3.62 ± 0.06 | 3.55 ± 0.06 | p = 0.48 |
| PiB (neocortex) | 1.09 ± 0.01 | 1.33 ± 0.04 | p < 0.001 |
Brain measures include FreeSurfer-calculated hippocampal volume, entorhinal thickness, and Pittsburgh compound-B (PiB) amyloid retention within the neocortical regions of interest. Note that APOE4 status was identified for 46 of 48 older adults, and p values reflect two-samples t test between Aβ− and Aβ+ older adults. n, Number of subjects; VIQ, verbal intelligence quotient; CDR, clinical dementia rating; MMSE, mini-mental state exam; BNT, Boston Naming Test.