Table 3.
Diagnostic accuracy of combinations of CSF Aβ 42/40 and CSF pT217T217 biomarkers for AD and FTD‐MAPT R406W.
| Test | Diagnostic groups | n per group | AUC | 95% CI | p value | Sensitivity% | Specificity% | Cutoff |
|---|---|---|---|---|---|---|---|---|
| CSF Aβ 42/40 | AD versus R406W | 80 versus 5 | 0.978 | 0.947–1.000 | 0.0004 | 100.0 | 96.3 | >0.0985 |
| AD versus 4R tauopathy | 80 versus 69 | 0.946 | 0.905–0.988 | <0.0001 | 94.2 | 90.0 | >0.0768 | |
| Control versus AD | 98 versus 80 | 0.925 | 0.882–0.969 | <0.0001 | 91.3 | 87.8 | <0.0798 | |
| Control versus R406W | 98 versus 5 | 0.588 | 0.384–0.791 | 0.5094 | 60.0 | 66.3 | >0.1302 | |
| 4R tauopathy versus R406W | 69 versus 5 | 0.548 | 0.329–0.767 | 0.7223 | 55.4 | 62.5 | <0.1298 | |
| Control versus 4R tauopathy | 98 versus 69 | 0.543 | 0.454–0.631 | 0.3459 | 56.5 | 55.1 | >0.1231 | |
| CSF pT217/T217 | Control versus AD | 98 versus 80 | 0.951 | 0.916–0.987 | <0.0001 | 96.3 | 92.9 | >4.325 |
| AD versus 4R tauopathy | 80 versus 69 | 0.945 | 0.907–0.983 | <0.0001 | 88.4 | 96.3 | <4.338 | |
| Control versus R406W | 98 versus 5 | 0.908 | 0.829–0.987 | 0.0021 | 100.0 | 76.5 | >3.678 | |
| AD versus R406W | 80 versus 5 | 0.878 | 0.799–0.956 | 0.0048 | 100.0 | 80.0 | <5.917 | |
| 4R tauopathy versus R406W | 69 versus 5 | 0.875 | 0.797–0.954 | 0.0053 | 81.2 | 100.0 | <3.675 | |
| Control versus 4R tauopathy | 98 versus 69 | 0.525 | 0.435–0.615 | 0.5895 | 65.2 | 45.9 | <3.037 | |
| CSF pT217/T217 × CSF Aβ 42/40 | Control versus R406W | 98 versus 5 | 0.961 | 0.924–0.998 | <0.0001 | 100.0 | 94.9 | >0.522 |
| 4R tauopathy versus R406W | 69 versus 5 | 0.948 | 0.897–0.999 | 0.0009 | 92.8 | 100.0 | <0.522 | |
| Control versus AD | 98 versus 80 | 0.814 | 0.748–0.880 | <0.0001 | 66.3 | 90.8 | >0.448 | |
| AD versus 4R tauopathy | 80 versus 69 | 0.793 | 0.719–0.868 | <0.0001 | 85.5 | 68.8 | <0.436 | |
| AD versus R406W | 80 versus 5 | 0.733 | 0.602–0.863 | 0.0824 | 100.0 | 60.0 | >0.515 | |
| Control versus 4R tauopathy | 98 versus 69 | 0.521 | 0.432–0.611 | 0.6375 | 73.9 | 36.7 | >0.332 | |
| CSF pT217/T217 divided by CSFAβ 42/40 | AD versus R406W | 80 versus 5 | 0.963 | 0.922–1.000 | 0.0005 | 100.0 | 95.0 | <61.1 |
| AD versus 4R tauopathy | 80 versus 69 | 0.953 | 0.915–0.990 | <0.0001 | 92.8 | 95.0 | <67.6 | |
| Control versus AD | 98 versus 80 | 0.950 | 0.912–0.987 | <0.0001 | 95.0 | 94.9 | >69.8 | |
| 4R tauopathy versus R406W | 69 versus 5 | 0.817 | 0.701–0.934 | 0.0184 | 85.5 | 80.0 | <38.0 | |
| Control versus R406W | 98 versus 5 | 0.804 | 0.694–0.914 | 0.0222 | 80.0 | 82.7 | >39.9 | |
| Control versus 4R tauopathy | 98 versus 69 | 0.533 | 0.443–0.623 | 0.4746 | 14.5 | 94.9 | <17.0 |
CSF, cerebrospinal fluid; AD, Alzheimer’s disease; AUC, area under the curve; FTD, frontotemporal dementia.