Table 1.
Participant characteristics at baseline
| Characteristic | Full Sample with CSF data N=349 | Cognitively Healthy N=105 | Participants wtth MCI N=244 | Comparison of Cognitively healthy and MCI P-value |
|---|---|---|---|---|
| Mean Baseline Age, years (SD) | 72.4 (7.09) | 74.5 (5.84) | 71.5 (7.39) | <0.001 |
| Mean follow-up time, years (SD) | 2.32 (0.682) | 2.01 (0.421) | 2.45 (0.730) | <0.001 |
| Mean Education, years (SD) | 16.2 (2.63) | 16.5 (2.61) | 16.1 (2.64) | 0.221 |
| APOE e4 status, N(%) | - | - | - | - |
| e4 Positive | 132 (37.8) | 24 (23) | 108 (44) | <0.001 |
| e4 Negative | 217 (62.2) | 81 (77) | 136 (56) | |
| Race, N(%) | - | - | - | - |
| African American | 8 (2.3) | 3 (2.9) | 5 (2.0) | 0.914 |
| American Indian/Alaska Native | 2 (0.57) | 1 (0.95) | 1 (0.41) | |
| Asian American | 4 (1.1) | 1 (0.95) | 3 (1.2) | |
| Native Hawaiian/Pacific Islander | 1 (0.29) | 0 (0.00) | 1 (0.41) | |
| White | 325 (93.1) | 99 (94) | 226 (93) | |
| More than one race | 7 (2.0) | 1 (0.95) | 6 (2.5) | |
| Unknown | 2 (0.57) | 0 (0.00) | 2 (0.82) | |
| Ethnicity, N(%) | - | - | - | - |
| Non-Hispanic | 341 (98.8) | 104 (99) | 237 (97) | 0.202 |
| Hispanic | 6 (1.7) | 0 (0.00) | 6 (2.4) | |
| Unknown | 2 (0.57) | 1 (0.95) | 1 (0.41) | |
| Conversion status, N(%) | - | - | - | - |
| No conversion | 298 (85.4) | 95 (90.5) | 203 (83.2) | 0.098 |
| Converted to MCI | 9 (2.6) | 9 (8.6) | - | - |
| Converted to AD | 42 (12.0) | 1 (0.9) | 41 (16.8) | - |
| Mean IICV, value (SD) | 0.620 (0.315) | 0.575 (0.274) | 0.639 (0.329) | 0.198 |
| Mean ANART, score (SD) | 11.0 (8.00) | 9.48 (7.22) | 11.6 (8.24) | 0.015 |
| Mean RAVLT, total of learning trials (SD) | 39.4 (10.9) | 44.4 (10.0) | 37.3 (10.6) | <0.001 |
| Mean time to complete Trails A. seconds (SD) | 36.4 (13.4) | 33.8 (9.78) | 37.5 (14.5) | 0.095 |
| Mean time to complete Trails B. seconds (SD) | 97.7 (52.7) | 83.6 (42.0) | 104 (55.6) | <0.001 |
| Mean CSF Aβ42, ng/l (SD) | 179 (49.9) | 188 (48.4) | 176 (50.2) | 0.029 |
| Mean CSF p-tau181, ng/l (SD) | 38.6 (22.8) | 34.0 (15.3) | 40.5 (25.1) | 0.085 |
| Mean p-tau/Aβ42 ratio (SD) | 0.252 (0.201) | 0.203 (0.127) | 0.273 (0.222) | 0.047 |
Abbreviations:
APOE: Apolipoprotein E
MCI: Mild Cognitive Impairment
AD: Alzheimer’s disease
IICV: Intra-individual cognitive variability
ANART: American National Adult Reading Test
RAVLT: Rey Auditory Verbal Learning Test
Statistical tests:
P-values are from Mann-Whitney U tests for continuous items and Fisher’s Exact test for categorical items
Note:
The CSF analytic sample is a subset of the full IICV dataset, precluding group comparisons.