Cross-Sectional and Longitudinal Study Participants
| Clinical diagnosis group | Aβ− | Aβ+ | Total |
| Probable AD | 16 (10) | 30 (19) | 46 (29) |
| MCI | 49 (33) | 47 (28) | 96 (61) |
| Older CN (>50 y) | 52 (47) | 5 (5) | 57 (52) |
| Younger CN (≤40 y) | 16 (0) | 0 (0) | 16 (0) |
| All | 133 (90) | 82 (52) | 215 (142) |
MCI = mild cognitive impairment.
Data are number at visit 1, followed by number at visit 2 in parentheses.