Sample demographics and clinical characteristicsa
| Characteristics | All | PIB− | PIB+ | PIB− vs PIB+ |
|---|---|---|---|---|
| No. (% women) | 40 (48%) | 24 (50%) | 16 (44%) | χ21 = 0.15, P = .70 |
| Age (yr) | 71 ± 5 | 70 ± 6 | 72 ± 4 | t38 = −1.19, P = .24 |
| APOE ϵ4 carriers (%) | 12 (31) | 4 (17) | 8 (53) | χ21 = 5.83, P = .02 |
| Body mass index (kg/m2) | 27 ± 3 | 28 ± 3 | 26 ± 2 | t38 = 2.14, P = .04 |
| Systolic blood pressure (mm Hg) | 137 ± 15 | 138 ± 15 | 136 ± 15 | t38 = 0.31, P = .76 |
| Diastolic blood pressure (mm Hg) | 81 ± 8 | 80 ± 8 | 82 ± 9 | t38 = −0.65, P = .52 |
| Total serum cholesterol level (mmol/L) | 5.2 ± 1 | 4.9 ± 1 | 5.5 ± 1 | t38 = 1.69, P = .10 |
| Education (yr) | 9 (2) | 9 (2.75) | 8 (2) | U = 158, P= .36 |
| Physical activity ≥ twice per week (%) | 63 | 52 | 80 | χ21 = 3.02, P = .08 |
| Mini-Mental State Examination | 27 (2) | 27 (2) | 27 (3) | U = 158, P = .35 |
| Total composite z score | 0.03 ± 0.5 | 0.06 ± 0.6 | −0.01 ± 0.5 | F1,37 = 0.018, P = .90 |
| Memory z score | −0.05 ± 0.6 | −0.10 ± 0.5 | 0.06 ± 0.7 | F1,37 = 2.42, P = .13 |
| Executive function z score | 0.04 ± 0.6 | 0.20 ± 0.6 | −0.10 ± 0.4 | F1,37 = 1.94, P = .17 |
| Processing speed z score | 0.2 (0.9) | 0.4 (1) | 0.2 (1) | F1,37 = 0.03, P = .86 |
| Dementia risk score | 7.5 (3.75) | 8 (3.75) | 7 (2) | U = 161, P = .39 |
| Fazekas score | 1 (2) | 1 (2) | 2 (1.75) | U = 144, P = .18 |
↵a Data are given as mean ± SD or median (interquartile range).