Table 3 |.
Prediction of amyloid and tau PET abnormalities with dichotomous plasma P-tau181 and P-tau217 results using different methods for selecting cutpoints.
| P-tau Measure | Negative N (%) | Positive N (%) | Sens | Spec | PPV | NPV | Youden | Unadjusted AUROC | Adjusted * AUROC | Adj onlya AUROC |
|---|---|---|---|---|---|---|---|---|---|---|
| Amyloid PET >=1.48 | ||||||||||
| Cutpoints defined as 1.96 standard deviations above the mean among participants who were CU, A−, and without history or stroke, myocardial infarction, or chronic kidney disease | ||||||||||
| P-tau 181 >=1.57 | 51 / 637 (8.0%) | 213 / 414 (51.4%) | 51.4 | 91.9 | 80.6 | 74.4 | 43.3 | 0.717 (0.691, 0.744) | 0.825 (0.801, 0.850) | 0.754 (0.726, 0.783) |
| P-tau 217 >=0.25 | 23 / 637 (3.6%) | 211 / 414 (51.0%) | 50.9 | 96.3 | 90.1 | 75.1 | 47.2 | 0.737 (0.712, 0.762) | 0.837 (0.813, 0.861) | 0.754 (0.726, 0.783) |
|
| ||||||||||
| Cutpoints defined as 1.96 standard deviations above the mean among all participants who were CU and A− | ||||||||||
| P-tau 181 >=1.75 | 26 / 637 (4.1%) | 172 / 414 (41.5%) | 41.5 | 95.9 | 86.8 | 71.6 | 37.4 | 0.687 (0.662, 0.712) | 0.819 (0.794, 0.844) | 0.754 (0.726, 0.783) |
| P-tau 217 >=0.26 | 12 / 637 (1.9%) | 193 / 414 (46.6%) | 46.6 | 98.1 | 94.1 | 73.8 | 44.7 | 0.724 (0.699, 0.748) | 0.833 (0.809, 0.858) | 0.754 (0.726, 0.783) |
|
| ||||||||||
| Temporal Meta ROI Tau PET >=1.29 | ||||||||||
| Cutpoints defined as 1.96 standard deviations above the mean among participants who were CU, A−, and without history or stroke, myocardial infarction, or chronic kidney disease | ||||||||||
| P-tau 181 >=1.57 | 30 / 430 (7.0%) | 18 / 65 (27.7%) | 27.6 | 93.0 | 37.5 | 89.4 | 20.6 | 0.604 (0.547, 0.660) | 0.798 (0.746, 0.850) | 0.788 (0.736, 0.839) |
| P-tau 217 >=0.25 | 43/430 (10.0%) | 26/65 (40.0%) | 40.0 | 90.0 | 37.6 | 90.8 | 30.0 | 0.650 (0.588, 0.712) | 0.804 (0.752, 0.855) | 0.788 (0.736, 0.839) |
|
| ||||||||||
| Cutpoints defined as 1.96 standard deviations above the mean among all participants who were CU and A− | ||||||||||
| P-tau 181 >=1.75 | 21 / 430 (4.9%) | 13 / 65 (20.0%) | 20.0 | 95.1 | 38.2 | 88.7 | 15.1 | 0.576 (0.526, 0.626) | 0.792 (0.739, 0.844) | 0.788 (0.736, 0.839) |
| P-tau 217 >=0.26 | 33 / 430 (7.7%) | 23 / 65 (35.4%) | 35.3 | 92.3 | 41.0 | 90.4 | 27.6 | 0.639 (0.579, 0.698) | 0.804 (0.753, 0.855) | 0.788 (0.736, 0.839) |
|
| ||||||||||
| ERC Tau PET >=1.27 | ||||||||||
| Cutpoints defined as 1.96 standard deviations above the mean among participants who were CU, A−, and without history or stroke, myocardial infarction, or chronic kidney disease | ||||||||||
| P-tau 181 >=1.57 | 24 / 446 (5.4%) | 24 / 49 (49.0%) | 48.9 | 94.6 | 50.0 | 94.4 | 43.5 | 0.718 (0.647, 0.789) | 0.872 (0.825, 0.919) | 0.800 (0.748, 0.852) |
| P-tau 217 >=0.25 | 38/446 (8.5%) | 31 / 49 (63.3%) | 63.2 | 91.4 | 44.9 | 95.7 | 54.6 | 0.774 (0.704, 0.843) | 0.869 (0.823, 0.916) | 0.800 (0.748, 0.852) |
|
| ||||||||||
| Cutpoints defined as 1.96 standard deviations above the mean among all participants who were CU and A− | ||||||||||
| P-tau 181 >=1.75 | 16 / 446 (3.6%) | 18 / 49 (36.7%) | 36.7 | 96.4 | 52.9 | 93.2 | 33.1 | 0.666 (0.597, 0.734) | 0.857 (0.808, 0.906) | 0.800 (0.748, 0.852) |
| P-tau 217 >=0.26 | 28 / 446 (6.3%) | 28 / 49 (57.1%) | 57.1 | 93.7 | 50.0 | 95.2 | 50.8 | 0.754 (0.683, 0.825) | 0.872 (0.826, 0.918) | 0.800 (0.748, 0.852) |
a
Adjusted variables included age and sex. The Adj only column is the AUROC for age and sex alone.
A−, not having elevated brain amyloid, CU, cognitively unimpaired; ERC, entorhinal cortex; NPV, negative predictive value; PPV, positive predictive value; ROI, Region of Interest; Sens, sensitivity; Spec, specificity.