Table 1.
Baseline characteristics in cognitively intact, aMCI, and nonaMCI groups.
| Variable | Cognitively Intact N = 8022 |
aMCI n = 3652 |
nonaMCI n = 960 |
|---|---|---|---|
| Demographic | Mean (SD) | Mean (SD) | Mean (SD) |
| Age | 71.59 (10.67) | 74.50 (9.40)a | 72.21 (9.69)c |
| Education | 15.44 (3.08) | 14.85 (3.52)a | 14.44 (3.73)b,c |
| Gender M/F (% F) | 2761/5261 (66%) |
1798/1854 (51%)a |
433/527 (55%)b |
| Race | |||
| Caucasian | 6488 (81%) | 2925 (80%) | 702 (73%)b,c |
| African American | 1201 (15%) | 495 (14%) | 189 (20%) |
| Other | 312 (4%) | 226 (6%) | 61 (6%) |
| Missing | 21 (<1%) | 6 (<1%) | 8 (1%) |
| Neuropsychological | |||
| MMSE | 28.85 (1.46) | 26.90 (2.52)a | 27.55 (2.34)b,c |
| Logical Mem Delayed | 12.10 (4.26) | 6.01 (4.51)a | 9.73 (4.26)b,c |
| Trail-making Test A (seconds) | 35.43 (17.04) | 46.98 (25.42)a | 48.43 (24.39)b |
| Trail-making Test B (seconds) | 93.27 (53.00) | 142.89 (78.24)a | 160.28 (83.67)b,c |
| Executive Dysfunction Groups No/Yes (% Yes in group) | 7085/685 (9%) | 2377/1069 (29%)a | 541/360 (38%)b,c |
| Digit Symbol Substitution Task | 46.83 (13.01) | 36.36 (12.70)a | 35.44 (12.50)b |
| Clinical Dementia Rating | |||
| CDR Global 0/0.5 (% 0.5) | 7154/868 (11%) | 270/3310 (91%) | 251/686 (72%) |
| Diagnosis: Clinician/Consensus (% Consensus) | 2328/5694 (71%) | 627/3025 (83%)a | 96/864 (90%)b,c |
| Physical Health | |||
| Hypertension No/Yes (% Yes) | 4067/3768 (47%) | 1641/1991 (55%)a | 380/557 (58%)b |
| Diabetes No/Yes (% Yes) | 7161/861 (11%) | 3160/492 (14%)a | 795/165 (17%)b,c |
| Body Mass Index | 26.96 (5.91) | 26.29 (5.88)a | 26.85 (6.43)c |
| Normal/Overweight Obese (% Overweight/Obese) | 2923/4678 (62%) |
1413/1980 (58%)a |
336/539 (62%) |
| Psychiatric | |||
| Geriatric Depression Scale | 1.43 (2.12) | 2.55 (2.70)a | 2.76 (2.95)b |
| Geriatric Depression Scale ≥ 5, % (n) | 8% (619) | 18% (667)a | 21% (197)b |
| Function | |||
| Functional Activities Questionnaire | 0.39 (1.73) | 3.73 (5.25)a | 3.01 (4.91)b,c |
Note.
Abbreviations: MCI, mild cognitive impairment; aMCI, amnestic MCI; nonaMCI, nonamnestic MCI; MMSE, Mini Mental State Exam; Logical Mem Delayed, Logical Memory II (delayed recall); CDR, Clinical Dementia Rating Scale; Executive Dysfunction groups based on Trail-making Test B – Trail-making Test A ≥ 114 (1 SD worse than the cognitively intact depressed sample). Race, Other = this category combined rates from the American Indian or Alaska Native, Native Hawaiian or Other Pacific Islander, Asian, or Other categories as rates within each of these categories were low in all three groups (those classified in the NACC data as Missing remained in this category). Percentages are based on total sample. Data presented as mean (SD) unless otherwise indicated. Neuropsychological scores are raw scores. Post hoc comparisons were conducted only when the omnibus effect in the Analysis of variance or Chi square tests was significant.
Significant difference in post hoc comparisons between the cognitively intact and aMCI groups (p<.01).
Significant difference in post hoc comparisons between cognitively intact and nonaMCI groups (p<.01).
Significant difference in post hoc comparisons between aMCI and nonaMCI groups (p<.01).