Table 1.
Demographics and Cognitive Measures by Diagnostic Group
| Variable | Normal control (n = 99) | Mild cognitive impairment (n = 92) | Alzheimer’s disease (n = 68) | p valuea | |
|---|---|---|---|---|---|
| Demographics | Age (years), mean (SD) | 79.2 (7.1) | 78.1 (6.4) | 78.2 (6.5) | .44 |
| Female, n (%) | 72 (72.7) | 42 (45.6) | 43 (63.2) | <.001 | |
| African American, n (%) | 9 (9.1) | 8 (8.7) | 4 (5.9) | .73 | |
| College graduate, n (%) | 66 (66.7) | 55 (59.8) | 38 (55.9) | .34 | |
| Right handed, n (%) | 94 (95.0) | 82 (89.1) | 64 (94.1) | .48 | |
| Memory | Cognitive Composite Score, mean (SD) | 0.0 (1.0) | −2.4 (1.5) | −4.1 (1.1) | .001 |
| PVLT-Immediate memory, mean (SD) | 39.2 (4.2) | 29.5 (6.7) | 23.2 (6.3) | .001 | |
| PVLT-Long Delay, mean (SD) | 7.5 (2.0) | 4.0 (2.9) | 1.1 (1.9) | .001 | |
| PVLT-Intrusions, mean (SD) | 1.6 (3.1) | 6.1 (6.0) | 8.3 (7.8) | <.001 | |
| PVLT- Perseverations, mean (SD) | 0.9 (1.7) | 1.6 (2.0) | 1.0 (1.7) | .01 | |
| BFLT-Immediate memory, mean (SD) | 93.5 (22.1) | 53.4 (28.6) | 22.7 (19.7) | <.001 | |
| BFLT-Long Delay, mean (SD) | 21.4 (5.4) | 11.2 (7.4) | 3.2 (5.4) | .001 | |
| BFLT-Intrusions, mean (SD) | 0.1 (0.5) | 0.2 (0.5) | 1.0 (2.9) | <.001 | |
| BFLT-Perseverations, mean (SD) | 0.1 (0.4) | 0.1 (0.4) | 0.1 (0.3) | .91 | |
| Global Cognition | MMSE, mean (SD) | 29.2 (1.0) | 27.3 (2.2) | 24.4 (2.7) | .001 |
| MoCA, mean (SD) | 26.8 (2.3) | 22.0 (3.2) | 18.6 (3.7) | .001 | |
| Cognitive Reserve | WTAR IQ, mean (SD) | 114.1 (9.2) | 110.6 (11.0) | 110.8 (11.0) | .06 |
| WAIS-III IS, mean (SD) | 14.6 (2.5) | 12.0 (2.9) | 9.5 (2.2) | <.001 | |
| Executive Function | GPG unique designs, mean (SD) | 16.2 (2.5) | 13.8 (3.3) | 11.7 (4.2) | <.001 |
| GPG generation rule violations, mean (SD) | 0.7 (1.3) | 1.7 (3.0) | 2.9 (3.7) | <.001 |
Note: AD = Alzheimer’s disease; BFLT = Biber Figure Learning Task; GDS = Geriatric Depression Scale; GPG = Graphic Pattern Generation; IQ = Intelligence Quotient; MCI = Mild Cognitive Impairment; MMSE = Mini-Mental State Exam; MoCA = Montreal Cognitive Assessment; PVLT = Philadelphia Verbal Learning Task; WAIS-III IS = Wechsler Adult Intelligence Scale third edition Information subtest; WTAR = Wechsler Test of Adult Reading.
aChi-square test with 2 degrees of freedom for categorical variables. For rank variables, Kruskall–Wallis test with correction for ties for the other variables.