Table 1.
Demographic and Clinical Characteristics of Study Participants, by Race
| Variable | European Americans (N = 684) | African Americans (N = 520) | Full sample (N = 1,204) | p-Value (AA vs EA) |
|---|---|---|---|---|
| Age, y | 65.8 (9.8) | 58.9 (9.6) | 62.8 (10.3) | <.0001 |
| Female | 360 (52.6) | 314 (60.4) | 674 (56.0) | .0088 |
| Education | <.0001 | |||
| <12 (less than high school) | 103 (15.1) | 63 (12.1) | 166 (13.8) | |
| =12 (high school graduate) | 305 (44.7) | 144 (27.7) | 449 (37.4) | |
| >12 (more than high school) | 274 (40.2) | 313 (60.2) | 587 (48.8) | |
| Education (WRAT) | ||||
| <12 (less than high school) | 395 (80.9) | |||
| =12 (high school graduate) | 59 (12.1) | |||
| >12 (more than high school) | 34 (7.0) | |||
| Ever smokers | 362 (53.3) | 283 (54.7) | 645 (53.9) | .5866 |
| Hypertension | 606 (88.9) | 440 (86.4) | 1046 (87.8) | .2087 |
| Hemoglobin A1c (%) | 7.5 (1.4) | 8.0 (2.0) | 7.7 (1.7) | <.0001 |
| Statin | 333 (48.9) | 283 (55.0) | 616 (51.5) | .0353 |
| Prior cardiovascular disease | 234 (35.8) | 134 (25.8) | 368 (31.4) | .0003 |
| Age of diabetes, y | 50.6 (10.5) | 45.6 (10.1) | 48.4 (10.6) | <.0001 |
| Duration of diabetes, y | 15.2 (7.7) | 13.3 (7.7) | 14.3 (7.8) | <.0001 |
| Waist (cm) | 109.7 (15.7) | 112.6 (17.3) | 111.0 (16.5) | .0166 |
| Hip (cm) | 115.3 (15.3) | 119.0 (17.2) | 116.9 (16.3) | .0002 |
| Body mass index, mean (SD) [kg/m2] | 32.7 (6.5) | 34.7 (8.0) | 33.5 (7.2) | <.0001 |
| Systolic blood pressure (mm Hg) | 130.5 (17.6) | 131.6 (18.1) | 131.0 (17.8) | .2656 |
| Diastolic blood pressure (mm Hg) | 71.3 (10.0) | 76.8 (11.1) | 73.7 (10.9) | <.0001 |
| Glucose (mg/dL) | 146.5 (54.1) | 149.8 (65.1) | 148.0 (59.2) | .9075 |
| Total intracranial volume (cc) | 1355 (136.8) | 1293 (136.2) | 1328 (139.9) | <.0001 |
| Gray matter volume (cc) | 522.1 (54.6) | 553.8 (64.0) | 535.8 (60.9) | <.0001 |
| White matter volume (cc) | 571.0 (69.5) | 495.0 (64.9) | 538.1 (77.3) | <.0001 |
| White matter lesion volume (cc) | 4.6 (8.7) | 6.5 (13.1) | 5.5 (10.9) | .0921 |
| Median (IQR) | 1.6 (0.2, 5.0) | 1.5 (0.2, 6.4) | 1.6 (0.2, 5.3) | |
| Hippocampal gray matter volume (cc) | 8.9 (1.2) | 9.2 (1.0) | 9.0 (1.1) | .0002 |
| Modified mini mental state exam | 91.0 (6.9) | 86.0 (8.3) | 88.8 (8.0) | <.0001 |
| RAVLT (sum of 5 trials, 0–75) | 40.8 (10.2) | 37.8 (8.8) | 39.5 (9.7) | <.0001 |
| Digit symbol substitution (0–133) | 50.3 (16.1) | 49.4 (16.4) | 49.9 (16.3) | .1964 |
| RAVLT delayed recall (0–15) | 7.0 (3.5) | 5.6 (3.2) | 6.4 (3.5) | <.0001 |
| Stroop (Trial 3 – Trial 1, s) | 39.7 (20.2) | 38.5 (17.3) | 39.2 (19.0) | .3308 |
| Median (IQR) | 34.0 (28.0, 46.0) | 35.0 (28.0, 47.0) | 35.0 (28.0, 46.0) | |
| Category fluency for animals | 16.6 (4.7) | 15.7 (4.6) | 16.2 (4.7) | .0013 |
| Median (IQR) | 16.0 (13.0, 20.0) | 15.0 (13.0, 19.0) | 16.0 (13.0, 19.0) | |
| Anxiety | 4.4 (3.8) | 5.0 (4.5) | 4.7 (4.2) | .0124 |
| Median (IQR) | 3.0 (2.0, 6.0) | 4.0 (2.0, 7.0) | 3.0 (2.0, 7.0) | |
| Total CESD score | 7.7 (5.3) | 8.5 (5.6) | 8.1 (5.4) | .0126 |
| Median (IQR) | 7.0 (4.0, 10.0) | 7.0 (4.0, 12.0) | 7.0 (4.0, 11.0) | |
Notes: Data expressed as mean (SD) for continuous characteristics; n (%) for discrete characteristics; median (min–max) for variables with skewed distributions. RAVLT = Rey Auditory Verbal Learning Test; CES-D = Center for Epidemiological Studies-Depression; AA = African American; EA = European American.