Table 3.
Logistic regression analyses of clinical diagnostic group on CSF and FBP PET variables, adding 1 biomarker to the other to determine an additive contribution in distinguishing among groups.
| HC vs MCI | MCI vs AD | HC vs. AD | ||||
|---|---|---|---|---|---|---|
|
| ||||||
| Chi-Square (df) | P-value | Chi-Square (df) | P-value | Chi-Square (df) | P-value | |
| Test FBP PET without CSF | 5.7502 (1) | .0165 | 8.7197 (1) | .0031 | 14.3044 (1) | .0002 |
| Test of CSF Aβ1-42 when added to FBP PET | 0.5176 (1) | .4718 | 4.6972 (1) | .0302 | 1.9339 (1) | .1643 |
| Test of CSF t-tau when added to FBP PET | 1.6375 (1) | .2007 | 6.9011 (1) | .0086 | 10.7866 (1) | .0010 |
| Test of CSF p-tau when added to FBP PET | 0.3143 (1) | .5751 | 2.0160 (1) | .1556 | 9.5094 (1) | .0020 |
| Test Aβ1-42 without FBP PET | 0.6942 (1) | .4047 | 9.9783 (1) | .0016 | 11.5618 (1) | .0007 |
| Test of FBP PET when added to CSF Aβ1-42 | 5.5238 (1) | .0188 | 1.7866 (1) | .1813 | 3.5791 (1) | .0585 |
| Test CSF t-tau without FBP PET | 4.5379 (1) | .0332 | 13.2332 (1) | .0003 | 15.2843 (1) | <.0001 |
| Test of FBP PET when added to CSF t-tau | 2.6964 (1) | .1006 | 2.8014 (1) | .0942 | 5.4003 (1) | .0201 |
| Test CSF p-tau without FBP PET | 2.2812 (1) | .1310 | 6.1506 (1) | .0131 | 14.5239 (1) | .0001 |
| Test of FBP PET when added to CSF p-tau | 3.8047 (1) | .0511 | 5.1704 (1) | .0230 | 7.4634 (1) | .0063 |
Abbreviations: Aβ1-42 = beta-amyloid protein; AD = Alzheimer’s disease; CSF = cerebrospinal fluid; df = degrees of freedom; FBP PET = florbetapir-F18 positron emission tomography; HC = healthy controls; MCI = mild cognitive impairment; p-tau = phosphorylated tau181P; t-tau = total tau; vs = versus.
FBP PET includes all 6 regions of interest, and CSF includes all 5, unless otherwise specified. P-values that meet statistical significance with Holm-Bonferroni-corrected cutoff are in bold.