Table 1.
Demographics and key characteristics of the population in each biomarker group
| Characteristic | Biomarker-negative | At risk of AD | Preclinical AD below thresholds | Preclinical AD above thresholds | P value |
|---|---|---|---|---|---|
| No. of subjects | 24 | 63 | 16 | 17 | |
| Age (years), mean (SD) | 75.1 (7.4) | 73.9 (6.1) | 74.9 (6.2) | 78.6 (5.1) | 0.37 |
| Male, n (%) | 14 (58) | 35 (55) | 7 (44) | 7 (42) | 0.3 |
| Education (years), mean (SD) | 17.7 (2.5) | 16.3 (2.9) | 15.6 (2.4) | 16.7 (2.5) | 0.6 |
| MMSE score, mean (SD) | |||||
| Baseline | 29.1 (1.4) | 29.2 (0.96) | 28.9 (0.97) | 29 (0.92) | 0.81 |
| Follow-up | 29 (1.6) | 29 (1.1) | 28.4 (1.9) | 28.6 (1.3) | 0.27 |
| APOE-ε4 carrier, n (%) | 1 (4) | 17 (27) | 6 (38) | 6 (35) | 0.06 |
| P-tau (pg/ml), mean (SD) | 19.3 (2.9) | 35.8 (14.8)* | 36.5 (8.9)* | 56.4 (15.8)* | <0.001 |
| [18F]Florbetapir (SUVR), mean (SD) | 1 (0.03) | 1.12 (1)* | 1.25 (0.08)* | 1.35 (0.07)* | <0.001 |
| Follow-up (months), mean (SD) | 24.3 (0.98) | 23.8 (0.9) | 24.1 (1.8) | 24 (0.7) | 0.53 |
| Diagnostic at follow-up visit, n (%) | |||||
| Cognitively normal | 22 (91) | 55 (87.5) | 14 (88) | 12 (71) | – |
| Mild cognitive impairment | 2 (9) | 7 (11) | 2 (12) | 5 (29) | 0.2 |
| Dementia | 0 | 1 (1.5) | 0 | 0 | – |
The values in each group were compared using analysis of covariance for each variable except gender, APOE-ε4 carrier status, and diagnostic at follow-up, for which the chi-squared test was used.
MMSE Mini-Mental State Examination
*P < 0.05, vs. biomarkers-negative group, post-hoc analysis