Table 1. Sample demographic and clinical characteristics.
| Total Sample | Cognitively Normal at follow-up | Psychometric MCI at follow-up | |
|---|---|---|---|
| N | 184 | 156 | 28 |
| Age | |||
| At Wave 2 study visit | 58.6 (5.8) | 58.4 (5.9) | 59.6 (5.2) |
| At PiB-PET scan | 60.3 (5.8) | 60.0 (5.9) | 61.9 (5.0) |
| Sex (F/M; %F) | 126/58 (69%) | 107/49 (69%) | 19/9 (68%) |
| Education (years) | 16.1 (2.4) | 16.1 (2.3) | 15.7 (2.5) |
| WRAT-III standard score | 106.8 (9.3) | 106.7 (9.6) | 107.7 (8.0) |
| Years enrolled in WRAP | 7.7 (1.5) | 7.6 (1.5) | 8.3 (1.6) |
| APOE ε4 allele (ε 4/non- ε4; % ε4) | 73/111 (40%) | 61/95 (39%) | 12/16 (43%) |
| Parental history of AD (+/-; %+) | 133/51 (72%) | 109/47 (70%) | 24/4 (86%) |
| Cortical PiB DVR | 1.2 (0.2) | 1.1 (0.1) | 1.3 (0.2) |
| Interval: PiB-PET & Wave 2 | 1.4 (1.4) | 1.3 (1.3) | 2.0 (1.5) |
| WRAP visit | |||
| Interval: PiB-PET & most recent | 1.7 (0.8) | 1.8 (0.8) | 1.3 (0.9) |
| WRAP visit |
PiB-PET = [C-11]Pittsburgh compound B Positron Emission Tomography, WRAT-III = Wide Range Achievement Test – 3rd Edition reading subtest, PiB DVR = [C-11]Pittsburgh compound B Distribution Volume Ratio. WRAP = Wisconsin Registry for Alzheimer's Prevention, APOE = apolipoprotein E, AD = Alzheimer's disease