Table 1. Characteristics and Dementia Incidence by Cognitive Status at the Index Visit in 2011-2013.
| Characteristic | No. (%) | P Valuea | ||
|---|---|---|---|---|
| Total (N = 1553) | Participants With Normal Cognition (n = 1014) | Participants With MCI (n = 539) | ||
| Age, mean (SD), y | 76.0 (5.2) | 75.8 (5.3) | 76.5 (5.2) | .02 |
| Women | 946 (60.9) | 642 (63.3) | 304 (56.4) | .008 |
| African American | 436 (28.1) | 320 (31.6) | 116 (21.5) | <.001 |
| Education | ||||
| <High school | 199 (12.8) | 131 (12.9) | 68 (12.6) | .003 |
| High school | 644 (41.5) | 390 (38.5) | 254 (47.1) | |
| ≥College | 710 (45.7) | 493 (48.6) | 217 (40.3) | |
| APOE ε4 status | 437 (28.1) | 263 (25.9) | 174 (32.3) | .008 |
| Smoking history, pack-years | ||||
| Never | 671 (43.2) | 445 (43.9) | 226 (41.9) | .34 |
| <25 | 593 (38.2) | 391 (38.6) | 202 (37.5) | |
| ≥25 | 289 (18.6) | 178 (17.6) | 111 (20.6) | |
| Body mass index, mean (SD)b | 28.4 (5.6) | 28.4 (5.6) | 28.5 (5.7) | .63 |
| Total cholesterol level, mean (SD), mg/dL | 185.6 (42.5) | 185.6 (42.5) | 181.8 (42.5) | .11 |
| Hypertension | 1163 (74.9) | 750 (74.0) | 413 (76.6) | .25 |
| Diabetes | 500 (32.2) | 317 (31.3) | 183 (34.0) | .28 |
| Heart failure | 156 (10.0) | 89 (8.8) | 67 (12.4) | .02 |
| Stroke | 52 (3.3) | 29 (2.9) | 23 (4.3) | .14 |
| Depressive symptoms | 104 (6.7) | 60 (5.9) | 44 (8.2) | .09 |
| Incident dementia | 212 (13.7) | 70 (6.9) | 142 (26.3) | <.001 |
Abbreviation: APOE, apolipoprotein E ; MCI, mild cognitive impairment.
SI conversion factor: To convert total cholesterol to millimoles per liter, multiply by 0.0259.
a
Differences between participants with no cognitive impairment and MCI were compared using the χ2 test for binary and categorical variables and the 2-sample t test for continuous variables.
b
Calculated as weight in kilograms divided by height in meters squared.