Table 2. Participant Characteristics by Cognitive Functioning Trajectory.
| Characteristic | Mean (SD) (N = 1730)a | |||
|---|---|---|---|---|
| CN-stable trajectory (n = 337 [86.2%]) | CN-MCI trajectory (n = 54 [13.8%]) | MCI-stable trajectory (n = 519 [62.4%]) | MCI-AD trajectory (n = 313 [37.6%]) | |
| Protected attribute, No. (%) | ||||
| Sex | ||||
| Female | 173 (51.3) | 19 (35.2) | 213 (41.0) | 123 (39.3) |
| Male | 164 (48.7) | 35 (64.8) | 306 (59.0) | 190 (60.7) |
| Ethnicity | ||||
| Hispanic | 13 (3.8) | 5 (9.3) | 20 (3.9) | 10 (3.2) |
| Not Hispanic | 324 (96.2) | 49 (90.7) | 499 (96.1) | 303 (96.8) |
| Race | ||||
| Asian | 7 (2.1) | 2 (3.7) | 7 (1.3) | 6 (2.0) |
| Black | 24 (7.1) | 5 (9.3) | 22 (4.2) | 7 (2.2) |
| White | 303 (89.9) | 42 (77.7) | 479 (92.3) | 298 (95.2) |
| Otherb | 3 (0.9) | 5 (9.3) | 11 (2.2) | 2 (0.6) |
| Predictor | ||||
| CDR-SB | 0.08 (0.46) | 0.45 (0.77) | 1.41 (1.21) | 4.11 (3.28) |
| ADAS-Cog | ||||
| 11 | 5.4 (0.2) | 7.3 (3.7) | 9.0 (4.7) | 16.7 (9.0) |
| 13 | 84.9 (4.3) | 11.7 (5.5) | 14.4 (6.9) | 25.8 (11.1) |
| Mini Mental State Examination | 29.0 (1.2) | 28.8 (1.4) | 27.7 (2.2) | 24.3 (4.5) |
| RAVLT | ||||
| Immediate | 45.4 (10.4) | 39.4 (10.6) | 35.7 (11.3) | 25.2 (9.2) |
| Learning | 5.8 (2.4) | 4.8 (2.5) | 4.3 (2.6) | 2.4 (2.2) |
| Forgetting | 3.4 (2.8) | 4.2 (2.4) | 4.5 (2.5) | 4.7 (2.1) |
| RAVLT Percent Forgetting | 32.5 (31.9) | 47.6 (30.0) | 56.7 (36.6) | 83.3 (30.4) |
| Functional Activities Questionnaire | 1.8 (8.2) | 0.9 (2.2) | 2.6 (3.9) | 1.1 (0.8) |
| Montreal Cognitive Assessment | 25.8 (2.5) | 24.4 (2.8) | 23.8 (3.1) | 18.6 (5.3) |
| Volume, mm3 | ||||
| Ventricles, × 104 | 3.50 (1.95) | 4.23 (1.93) | 4.01 (2.32) | 4.88 (2.37) |
| Hippocampus, × 103 | 7.32 (0.92) | 6.89 (0.86) | 6.97 (1.11) | 5.91 (1.11) |
| Whole brain, × 106 | 1.01 (0.10) | 1.02 (0.09) | 1.04 (0.10) | 0.98 (0.11) |
| Entorhinal cortical, × 103 | 3.79 (0.61) | 3.56 (0.76) | 3.64 (0.71) | 2.99 (0.78) |
| Fusiform cortical, × 104 | 1.76 (0.24) | 1.76 (0.23) | 1.80 (0.26) | 1.59 (0.27) |
| Middle temporal cortical, × 104 | 2.00 (0.26) | 1.97 (0.24) | 2.01 (0.27) | 1.77 (0.30) |
| Intracranial, × 106 | 1.51 (0.15) | 1.56 (0.14) | 1.53 (0.16) | 1.54 (0.17) |
| PET | ||||
| 18F-AV-45 | 1.0 (0.1) | 1.1 (0.1) | 1.1 (0.2) | 1.3 (0.2) |
| FDG | 1.3 (0.1) | 1.2 (0.1) | 1.3 (0.1) | 1.1 (0.1) |
| CSF-β-amyloid level, pg/mL × 103 | 1.31 (0.61) | 1.31 (0.75) | 1.11 (0.58) | 0.68 (0.31) |
| τ level, pg/mL | ||||
| Total, × 102 | 2.40 (0.90) | 2.87 (0.87) | 2.69 (1.18) | 3.50 (1.46) |
| Phosphorylated | 22.0 (9.5) | 26.6 (8.5) | 25.5 (13.2) | 34.6 (16.3) |
Abbreviations: 18F-AV-45, florbetapir; AD, Alzheimer disease; ADAS-Cog, Alzheimer Disease Assessment Scale-Cognitive Subscale; CDR-SB, Clinical Dementia Rating-Sum of Boxes; CN, cognitively normal; FDG, fluorodeoxyglucose; MCI, mild cognitive impairment; PET, positron emission tomography; RAVLT, Rey Auditory Verbal Learning Test.
a
In the CN-MCI trajectory, participants had CN progression to MCI. In the MCI-AD trajectory, participants had MCI progression to AD. In CN-stable and MCI-stable trajectories, participants were observed with the same stage at baseline and final visit.
b
Includes American Indian or Alaskan Native, Hawaiian or Other Pacific Islander, and more than 1 reported race, and unknown race.