Table 2.
Baseline characteristics of participants in each of the four preclinical AD groups
| Using baseline CSF abeta1–42 and total tau to define group membership | ||||
|---|---|---|---|---|
| Baseline Participant Characteristics | Stage 0 | Stage1 | Stage 2 | SNAP |
| Variable | (N=102) | (N=46) | (N=28) | (n=46) |
| Age, mean number of years (SD) | 54.8 (10.3) | 56.8 (8.1) | 63.6 (9.9)** | 57.6 (9.9) |
| Follow-up time, mean years (SD) | 12.0 (3.5) | 10.0 (3.6)** | 8.6 (5.2)** | 11.2 (4.3) |
| Gender, females (%) | 60.8% | 58.7% | 57.1% | 60.9% |
| Ethnicity, Caucasians (%) | 96.1% | 97.8% | 100.0%* | 97.8% |
| ApoE ε4 carriers (%) | 23.5% | 34.8% | 50.0%* | 41.3* |
| MMSE, mean score (SD) | 29.6 (0.8) | 29.4 (0.9) | 29.6 (0.8) | 29.5 (0.8) |
| Education, mean years (SD) | 17.2 (2.4) | 16.9 (2.4) | 17.1 (2.1) | 17.2 (2.2) |
| Paired Associates Immediate (SD) | 20.3 (2.9) | 20.0 (3.4) | 20.3 (2.8) | 20.7 (2.9) |
| Logical Memory Delayed (SD) | 13.5 (3.8) | 13.0 (3.9) | 10.8 (4.5)* | 12.8 (4.1) |
| Boston Naming, % Correct (SD) | 96.1 (5.9) | 96.4 (5.7) | 94.8 (6.0) | 95.1 (6.5) |
| Digit Symbol Substitution (SD) | 54.5 (11.6) | 52.2 (12.5) | 47.9 (13.0)* | 53.4 (11.9) |
| Cognitive Composite, mean (SD) | 0.03 (0.6) | −0.06 (0.7) | −0.32 (0.6)* | −0.05 (0.6) |
| CSF abeta1–42 in pg/mL (SD) | 447.7 (51.7) | 315.3 (41.2)** | 250.8 (71.8)** | 476.9 (57.2) |
| CSF p-tau181 in pg/mL (SD) | 30.7 (8.7) | 26.6 (8.3) | 60.5 (22.7)** | 42.5 (13.5)** |
| CSF total tau in pg/mL (SD) | 56.8 (11.1) | 45.4 (13.3) | 109.6 (31.7)** | 95.8 (30.0)** |
| Using baseline CSF abeta1–42 and p-tau181 to define group membership | ||||
| Variable | (N=102) | (N=46) | (N=28) | (n=46) |
| Age, mean number of years (SD) | 56.0 (9.9) | 57.1 (8.5) | 63.1 (9.6)** | 55.1 (11.1) |
| Follow-up time, mean years (SD) | 12.4 (3.9) | 10.2 (3.9)** | 8.3 (4.7)** | 10.2 (3.1)** |
| Gender, females (%) | 58.8% | 54.3% | 64.3% | 65.2% |
| Ethnicity, Caucasians (%) | 96.1% | 97.8% | 100.0%* | 97.8% |
| ApoE ε4 carriers (%) | 25.5% | 34.8% | 50.0%* | 37.0% |
| MMSE, mean score (SD) | 29.5 (0.8) | 29.5 (0.9) | 29.6 (0.7) | 29.7 (0.7) |
| Education, mean years (SD) | 17.3 (2.4) | 17.1 (2.4) | 16.8 (2.2) | 17.0 (2.2) |
| Paired Associates Immediate (SD) | 20.4 (2.9) | 20.0 (3.5) | 20.3 (2.5) | 20.5 (2.9) |
| Logical Memory Delayed (SD) | 13.3 (3.9) | 13.0 (4.0) | 10.8 (4.3)* | 13.3 (4.0) |
| Boston Naming, % Correct (SD) | 95.9 (6.3) | 96.0 (6.2) | 95.5 (5.3) | 95.5 (5.7) |
| Digit Symbol Substitution (SD) | 54.1 (11.9) | 53.1 (12.9) | 46.5 (11.8)* | 54.4 (11.3) |
| Cognitive Composite, mean (SD) | 0.00 (0.6) | −0.06 (0.7) | −0.32 (0.6)* | 0.00 (0.6) |
| CSF abeta1–42 in pg/mL (SD) | 454.2 (57.2) | 308.1 (51.8)** | 262.7 (69.7)** | 462.5 (50.0) |
| CSF p-tau181 in pg/mL (SD) | 28.6 (7.2) | 25.6 (6.9) | 62.2 (20.7)** | 47.1 (9.8)** |
| CSF total tau in pg/mL (SD) | 61.9 (20.3) | 47.1 (16.7) | 106.9 (34.5)** | 84.7 (30.9)** |
Significant differences between Stages 1, 2, and SNAP relative to Stage 0 are indicated by asterisks: * p < 0.05; ** p < 0.005.