Table 3.
Association between plasma p-tau181, Alzheimer’s disease neuropathology and regional p-tau severity
| OR | 95% CI | P-value | AUC (95% CI), P-value | |
|---|---|---|---|---|
| Autopsy-confirmed Alzheimer’s disease (n = 62 versus n = 41 non-Alzheimer’s disease) | ||||
| Model 1 | 1.05 | 1.02–1.09 | <0.01 | 0.73 (0.63–0.83), <0.01 |
| Model 2 | 1.06 | 1.02–1.10 | <0.01 | 0.76 (0.67–0.86), <0.01 |
| Model 3 | 1.07 | 1.03–1.11 | <0.01 | 0.82 (0.74–0.91), <0.01 |
| Autopsy-confirmed Alzheimer’s disease, CDR <1.0 (n = 25 Alzheimer’s disease versus n = 32 non-Alzheimer’s disease) | ||||
| Model 1 | 1.04 | 0.99–1.08 | 0.05 | 0.71 (0.57–0.84), <0.01 |
| Model 2 | 1.05 | 1.01–1.10 | 0.02 | 0.78 (0.65–0.91), <0.01 |
| Autopsy-confirmed Alzheimer’s disease, CDR ≥1.0 (n = 37 Alzheimer’s disease versus n = 9 non-Alzheimer’s disease) | ||||
| Model 1 | 1.23 | 1.05–1.45 | 0.01 | 0.85 (0.73–0.97), <0.01 |
| Model 2 | 1.25 | 1.02–1.53 | 0.03 | 0.89 (0.78–0.99), <0.01 |
| Braak stage (n = 103) | 1.06 | 1.02–1.09 | <0.01 | – |
| CERAD neuritic plaque score (n = 103) | 1.05 | 1.02–1.08 | <0.01 | – |
| Regional p-tau severity (n = 90) | ||||
| Superior temporal cortex | 1.06 | 1.02–1.09 | <0.01 | – |
| Inferior parietal cortex | 1.04 | 1.01–1.07 | <0.01 | – |
| Entorhinal cortex | 1.06 | 1.02–1.10 | <0.01 | – |
| Amygdala | 1.04 | 1.01–1.07 | 0.03 | – |
| CA1-hippocampus | 1.06 | 1.02–1.10 | <0.01 | – |
| CA2-hippocampus | 1.03 | 1.01–1.06 | 0.02 | – |
Binary logistic regression examined the association between plasma p-tau181 levels and Alzheimer’s disease neuropathologic changes (per NIA–Reagan criteria). Model 1 examined plasma p-tau181 alone. Model 2 controlled for age at death, years between last blood draw and death, sex and APOE ε4 status. Model 3 controlled for Model 2 covariates in addition to global CDR (<1 and 1 or higher) score at time of blood draw. The AUC statistics for Models 2 and 3 were calculated using predicted probabilities from the binary logistic regression. P-values that examined the semiquantitative ratings of regional p-tau severity as outcomes (six total outcomes) were false discovery rate-adjusted using the Benjamini–Hochberg procedure and covariates included age at death, years between last blood draw and death, sex and APOE ε4 status.