TABLE 2.
Accuracy of individual plasma biomarkers and TabCAT-BHA in discriminating Aβ-PET status.
| AUC (95% CI) | SN | SP | PPV | NPV | |
|---|---|---|---|---|---|
| Total sample without covarlates (47 Aβ-PET negative vs. 58 Aβ-PET positive) | |||||
| Aβ42/40 | 0.750 (0.655–0.845) | 0.690 | 0.766 | 0.784 | 0.667 |
| pTau181 | 0.895 (0.832–0.959) | 0.879 | 0.809 | 0.850 | 0.844 |
| NfL | 0.493 (0.367–0.619) | 0.931 | 0.319 | 0.628 | 0.789 |
| GFAP | 0.772 (0.678–0.866) | 0.862 | 0.596 | 0.725 | 0.778 |
| TabCAT-BHA | 0.700 (0.602–0.799) | 0.345 | 1.000 | 1.000 | 0.553 |
| Total sample with covarlatea (45 Aβ-PET negative vs. 56 Aβ-PET positive) | |||||
| Aβ42/40 | 0.886 (0.824–0.948) | 0.679 | 0.933 | 0.927 | 0.700 |
| pTau181 | 0.933 (0.885–0.980) | 0.804 | 0.933 | 0.938 | 0.792 |
| NfL | 0.864 (0.793–0.935) | 0.786 | 0.822 | 0.846 | 0.755 |
| GFAP | 0.895 (0.835–0.956) | 0.875 | 0.778 | 0.831 | 0.833 |
| TabCAT-BHA | 0.918 (0.866–0.971) | 0.893 | 0.844 | 0.877 | 0.864 |
| SCI and MCI only without covariates (32 Aβ-PET negative vs. 38 Aβ-PET positive) | |||||
| Aβ42/40 | 0.790 (0.683–0.898) | 0.711 | 0.813 | 0.818 | 0.703 |
| pTau181 | 0.888 (0.808–0.967) | 0.921 | 0.750 | 0.814 | 0.889 |
| NfL | 0.527 (0.373–0.681) | 0.921 | 0.344 | 0.625 | 0.786 |
| GFAP | 0.772 (0.659–0.886) | 0.789 | 0.656 | 0.732 | 0.724 |
| TabCAT-BHA | 0.642 (0.513–0.772) | 0.474 | 0.781 | 0.720 | 0.556 |
| SCI and MCI only with covariatesa (31 Aβ-PET negative vs. 36 Aβ-PET positive) | |||||
| Aβ42/40 | 0.927 (0.867–0.986) | 0.806 | 0.935 | 0.935 | 0.806 |
| pTau181 | 0.939 (0.883–0.995) | 0.806 | 0.968 | 0.967 | 0.811 |
| NfL | 0.883 (0.798–0.967) | 0.889 | 0.774 | 0.821 | 0.857 |
| GFAP | 0.913 (0.843–0.983) | 0.889 | 0.839 | 0.865 | 0.867 |
| TabCAT-BHA | 0.883 (0.805–0.960) | 0.667 | 0.935 | 0.923 | 0.707 |
Abbreviations: Aβ-PET, amyloid β positron emission tomography; APOE, apolipoprotein E;AUC, area under the ROC curve; GFAP, glial fibrillary acidic protein; MCI, mild cognitive impairment; NfL, neurofilament light; NPV, negative predictive value; PPV, positive predictive value; SCI, subjective cognitive impairment; SN, sensitivity; SP, specificity; TabCAT-BHA, Tablet-based Cognitive Assessment Tool Brain Health Assessment.
a
Covariates include age (years), sex (female), education (years), presence of APOE ε4 allele (binary), and time difference between PET acquisition and plasma collection (days).