Table 2.
Selection of the most parsimonious model for predicting cognitive decline in patients with amnestic MCI and amnestic mild dementia
| Model | Plasma p- tau217 |
APOE ε4 status |
Plasma Aβ ratio |
Plasma NfL |
MR AD cortex |
Baseline cognition |
Tau-PET | R2 | p-value | AIC |
|---|---|---|---|---|---|---|---|---|---|---|
| Full plasma model | −0.11 (0.91) | 0.38 (0.71) | 0.54 (0.59) | −1.85 (0.07) | 2.43 (0.02) | 3.27 (0.001) | −4.89 (<0.0001) | 0.44 | <0.0001 | 108 |
| plasma model −1 | − | 0.37 (0.71) | 0.54 (0.59) | −1.87 (0.06) | 2.48 (0.01) | 3.28 (0.001) | −5.30 (<0.0001) | 0.44 | <0.0001 | 106 |
| plasma model −2 | − | − | 0.41 (0.68) | −1.99 (0.05) | 2.47 (0.02) | 3.27 (0.001) | −5.34 (<0.0001) | 0.44 | <0.0001 | 104 |
| plasma model −3 | − | − | − | −2.02 (0.046) | 2.48 (0.01) | 3.29 (0.001) | −5.49 (<0.0001) | 0.44 | <0.0001 | 103 |
| plasma model −4 | − | − | − | − | 2.36 (0.02) | 3.19 (0.002) | −5.59 (<0.0001) | 0.42 | <0.0001 | 105 |
| plasma model −5 | − | − | − | − | − | 3.18 (0.002) | −6.08 (<0.0001) | 0.39 | <0.0001 | 109 |
| plasma model −6 | − | − | − | − | − | − | −6.26 (<0.0001) | 0.33 | <0.0001 | 117 |
| Model | CSF p- tau217 |
APOE ε4 status |
CSF Aβ ratio |
MR AD cortex |
CSF NfL |
Baseline cognition |
Tau-PET | R2 | p-value | AIC |
| Full CSF model | 0.22 (0.82) | −0.67 (0.51) | −1.16 (0.25) | 2.56 (0.01) | −2.90 (0.005) | 3.13 (0.002) | −4.27 (<0.0001) | 0.47 | <0.0001 | 102 |
| CSF model −1 | − | −0.69 (0.49) | −1.32 (0.19) | 2.59 (0.01) | −2.91 (0.004) | 3.13 (0.002) | −5.26 (<0.0001) | 0.47 | <0.0001 | 100 |
| CSF model −2 | − | − | −1.13 (0.26) | 2.66 (0.009) | −2.84 (0.005) | 3.17 (0.002) | −5.32 (<0.0001) | 0.47 | <0.0001 | 98.8 |
| CSF model −3 | − | − | − | 2.70 (0.008) | −2.90 (0.005) | 3.04 (0.003) | −5.29 (<0.0001) | 0.46 | <0.0001 | 98.2 |
| CSF model −4 | − | − | − | − | −2.58 (0.01) | 3.04 (0.003) | −5.85 (<0.0001) | 0.42 | <0.0001 | 104 |
| CSF model −5 | − | − | − | − | − | 3.18 (0.002) | −6.08 (<0.0001) | 0.39 | <0.0001 | 109 |
| CSF model −6 | − | − | − | − | − | − | −6.26 (<0.0001) | 0.33 | <0.0001 | 117 |
Results from the stepwise regression model. The variable with the highest p-value was removed from the model and the R2 and AIC of the new model assessed. For both plasma and CSF analyses the lowest AIC was achieved with models containing [18F]RO948 (tau-PET), Neurofilament Light (NfL), and baseline cognitive data (data highlighted with light orange). All models included sex, education, age, and baseline MMSE as covariates. Tau-PET = [18F]RO948 Standardized Uptake Ratio values in a temporal ROI; MR AD cortex = Cortical thickness in “AD signature cortex” (see methods for details); Aβ ratio = Aβ42/40 ratio. Biomarker values indicate t-values (p-values).