Table 2. Plasma and Cerebrospinal Fluid (CSF) Characteristics of Cohorta.
| Biomarker | Sample, Total (Died), No. | Positive/Total No. (%) | Median (IQR) [Range]b | Correlation With Age, rc | P Value | Correlation With Barthel Index, rc | P Value |
|---|---|---|---|---|---|---|---|
| Plasma | |||||||
| t-tau | 24 (24) | NA | 8 (5-15) [2-153] | 0.21 | .32 | −0.10 | .66 |
| NfL | 24 (24) | NA | 150 (63-296) [27-776] | 0.22 | .03 | −0.53 | .01 |
| GFAP | 24 (24) | NA | 695 (362-1095) [264-2139] | −0.15 | .48 | 0.27 | .23 |
| CSF | |||||||
| t-tau | 125 (122) | NA | 2179 (1074-6274) [111-18 895] | −0.02 | .80 | −0.31 | .003 |
| t-tau Cutoffd | 125 (122) | 89/125 (71) | NA | NA | NA | NA | NA |
| p-tau | 49 (48) | NA | 53 (39-70) [11-125] | 0.21 | .15 | −0.03 | .84 |
| t-tau:p-tau Ratio | 47 (46) | NA | 1.9 (1.8-2.3) [1.6-3.2] | 0.14 | .33 | 0.18 | .27 |
| NfL | 49 (48) | NA | 6400 (3599-11 757) [905-36 850] | −0.05 | .74 | −0.44 | .005 |
| Aβ42 | 49 (48) | NA | 391 (252-558) [98-1051] | 0.06 | .68 | 0.23 | .15 |
| NSE | 123 (120) | NA | 37 (22-63) [2-263] | 0.05 | .57 | −0.34 | <.001 |
| NSE cutoffd | 123 (120) | 79/123 (64) | NA | NA | NA | NA | NA |
| 14-3-3 Proteind | 162 (159) | 84/162 (52) | NA | NA | NA | NA | NA |
| Negative | NA | 30/162 (19) | NA | NA | NA | NA | NA |
| Inconclusive | NA | 48/162 (30) | NA | NA | NA | NA | NA |
| RT-QuICd | 64 (61) | 53/64 (83) | NA | NA | NA | NA | NA |
Abbreviations: Aβ42, β-amyloid 42; GFAP, glial fibrillary acidic protein; IQR, interquartile range; NA, not applicable; NfL, neurofilament light; NSE, neuron-specific enolase; p-tau, phosphorylated; RT-QuIC, real-time quaking-induced conversion test; t-tau, total tau.
a
All continuous biomarkers are reported as pg/mL, except for NSE, which is reported as ng/mL.
b
Median shown rather than mean owing to skewing.
c
Pearson correlations with log-transformed biomarkers.
d
Dichotomized, with positive being ≥1150 pg/mL (National Prion Disease Pathology Surveillance Center) or ≥1200 pg/mL (Athena Diagnostics).