Table 2. Diagnostic Performance of [18F]flortaucipir PET in Distinguishing AD Dementia From Non-AD Neurodegenerative Diseasea.
| ROI (Threshold) | AUC (95% CI) | % (95% CI) | Positive Likelihood Ratio (95% CI) | Negative Likelihood Ratio (95% CI) | ||
|---|---|---|---|---|---|---|
| Accuracy | Sensitivity | Specificity | ||||
| Threshold Approach: Mean +2 × SD in All Controls (n = 160) | ||||||
| BioFINDER + UCSF + Seoul | n = 433 | n = 433 | n = 179 | n = 254 | n = 433 | (n = 433) |
| Entorhinal cortex (SUVR: 1.39) | 0.94 (0.91-0.96) | 87.8 (84.3-90.7) | 80.5 (73.9-86.0) | 92.9 (89.0-95.8) | 11.4 (7.2-17.8) | 0.21 (0.16-0.28) |
| Inferior temporal cortex (SUVR: 1.31) | 0.94 (0.92-0.97) | 90.1 (86.9-92.7) | 89.9 (84.6-93.9) | 90.2 (85.8-93.5) | 9.1 (6.3-13.3) | 0.11 (0.07-0.17) |
| Temporal meta-ROI (SUVR: 1.34)b | 0.95 (0.93-0.97) | 90.3 (87.1-92.9) | 89.9 (84.6-93.9) | 90.6 (86.3-93.9) | 9.5 (6.5-14.0) | 0.11 (0.07-0.17) |
| Temporoparietal cortex (SUVR: 1.26) | 0.93 (0.91-0.96) | 90.8 (87.6-93.3) | 86.0 (80.1-90.8) | 94.1 (90.5-96.7) | 14.6 (8.9-23.9) | 0.15 (0.10-0.21) |
| Braak stage V and VI (SUVR: 1.28)c | 0.92 (0.89-0.95) | 88.5 (85.1-91.3) | 79.9 (73.3-85.5) | 94.5 (90.9-97.0) | 14.5 (8.7-24.2) | 0.21 (0.16-0.29) |
| Threshold Approach: Youden Index Derived in Seoul Cohort (55 AD Dementia vs 90 Controls) | ||||||
| BioFINDER + UCSF | n = 289 | n = 289 | n = 124 | n = 165 | n = 289 | n = 289 |
| Entorhinal cortex (SUVR: 1.41) | 0.95 (0.93-0.98) | 89.6 (85.5-92.9) | 82.3 (74.4-88.5) | 95.2 (90.7-97.9) | 17.0 (8.6-33.5) | 0.19 (0.13-0.27) |
| Inferior temporal cortex (SUVR: 1.29) | 0.98 (0.96-0.99) | 88.6 (84.3-92.0) | 96.8 (92.0-99.1) | 82.4 (75.7-87.9) | 5.5 (4.0-7.7) | 0.04 (0.01-0.10) |
| Temporal meta-ROI (SUVR: 1.27)b | 0.98 (0.96-1.0) | 91.7 (87.9-94.6) | 96.8 (92.0-99.1) | 87.9 (81.9-92.4) | 8.0 (5.3-12.1) | 0.04 (0.01-0.10) |
| Temporoparietal cortex (SUVR: 1.27) | 0.97 (0.95-0.99) | 93.4 (89.9-96.0) | 90.3 (83.7-94.9) | 95.8 (91.5-98.3) | 21.3 (10.3-44.1) | 0.10 (0.06-0.17) |
| Braak stage V and VI (SUVR: 1.21)c | 0.96 (0.93-0.99) | 89.3 (85.1-92.6) | 93.6 (87.7-97.2) | 86.1 (79.8-91.0) | 6.7 (4.6-9.8) | 0.07 (0.04-0.15) |
| Threshold Approach: Youden Index Derived in BioFINDER Cohort (52 AD Dementia vs 66 Controls) | ||||||
| Seoul + UCSF | n = 308 | n = 308 | n = 127 | n = 181 | n = 308 | n = 308 |
| Entorhinal cortex (SUVR: 1.26) | 0.94 (0.91-0.97) | 82.1 (77.4-86.3) | 95.3 (90.0-98.3) | 72.9 (65.8-79.3) | 3.5 (2.8-4.5) | 0.06 (0.03-0.14) |
| Inferior temporal cortex (SUVR: 1.35) | 0.94 (0.91-0.97) | 89.6 (85.7-92.8) | 89.0 (82.2-93.8) | 90.1 (84.7-94.0) | 9.0 (5.8-13.9) | 0.12 (0.07-0.20) |
| Temporal meta-ROI (SUVR: 1.27)b | 0.94 (0.92-0.97) | 87.7 (83.5-91.1) | 92.1 (86.0-96.2) | 84.5 (78.4-89.5) | 6.0 (4.2-8.4) | 0.09 (0.05-0.17) |
| Temporoparietal cortex (SUVR: 1.21) | 0.93 (0.89-0.96) | 86.7 (82.4-90.3) | 89.8 (83.1-94.4) | 84.5 (78.4-89.5) | 5.8 (4.1-8.2) | 0.12 (0.07-0.20) |
| Braak stage V and VI (SUVR: 1.27)c | 0.91 (0.87-0.95) | 88.6 (84.6-92.0) | 79.5 (71.5-86.2) | 95.0 (90.8-97.7) | 16.0 (8.4-30.4) | 0.22 (0.15-0.30) |
Abbreviations: AD, Alzheimer disease; AUC, area under the curve; PET, positron emission tomography; ROI, region of interest; SUVR, standardized uptake value ratio; UCSF, University of California, San Francisco.
Diagnostic test measures were obtained using a threshold derived in all controls (n = 160) (mean +2 × SD) and applied to all participants with AD dementia (n = 179) and non-AD (n = 254) in the study, the Youden Index (55 with AD dementia vs 90 controls) in the Seoul cohort applied to participants with AD dementia (n = 124) and non-AD disorders (n = 165) from UCSF and BioFINDER cohorts, and the Youden Index (52 with AD dementia vs 66 controls) in BioFINDER cohort applied to participants with AD dementia (n = 127) and non-AD disorders (n = 181) from UCSF and Seoul cohorts.
Volume-weighted average of bilateral entorhinal, amygdala, fusiform, and inferior and middle temporal cortices.7,19,26
Based on a neuropathological staging system of neurofibrillary tangle pathology proposed by Braak and Braak.31 Stages I and II include (trans)entorhinal regions; III and IV, limbic areas; and V and VI, neocortical tangle pathology.