Table 1.
Sample Characteristics from the Baltimore Longitudinal Study of Aging (N=617)
| Baseline Characteristics | Overall N=617 | Females N=326 | Males N=291 | p-value for difference by sex |
|---|---|---|---|---|
| Age, in years, mean(SD) | 71.2 (8.7) | 70.3 (8.7) | 72.2 (8.5) | 0.008 |
| White, n(%) | 450 (72.9) | 214 (65.6) | 236 (81.1) | <0.001 |
| Education, in years, mean(SD) | 16.9 (2.5) | 16.6 (2.5) | 17.2 (2.5) | 0.005 |
| APOE e4 carrier status, n(%) | 127 (20.6) | 77 (23.6) | 50 (17.2) | 0.072 |
| Vascular Burden, n(%) | 0.055 | |||
| 0 conditions | 221 (35.5) | 105 (32.2) | 116 (39.3) | |
| 1 condition | 259 (42.0) | 151 (46.3) | 108 (37.1) | |
| 2+ conditions | 137 (22.2) | 70 (21.5) | 67 (23.0) | |
| Components of Vascular Burden, n(%) | ||||
| Diabetes | 26 (4.2) | 5 (1.5) | 21 (7.2) | <0.001 |
| Elevated Cholesterol | 231 (37.4) | 157 (48.1) | 74 (25.4) | <0.001 |
| Hypertension | 129 (20.9) | 51 (15.6) | 78 (26.8) | 0.001 |
| Obesity | 154 (25.0) | 85 (26.1) | 69 (23.7) | 0.643 |
| Current Smoker | 20 (3.2) | 4 (1.2) | 16 (5.5) | 0.003 |
| Systolic Blood Pressure, in mm Hg, mean(SD) | 119.0 (17.8) | 116.0 (16.4) | 122.3 (18.7) | <0.001 |
| Diastolic Blood Pressure, in mm Hg, mean(SD) | 67.6 (11.2) | 66.5 (10.7) | 68.8 (11.6) | 0.010 |
| Antihypertensive medications, n(%) | 265 (43.2) | 128 (39.3) | 137 (47.1) | 0.067 |
| HDL Cholesterol, in mg/dL, mean(SD) | 59.9 (17.5) | 67.1 (16.8) | 51.8 (14.5) | <0.001 |
| Baseline 3-T Scan, n(%) | 519 (84.1) | 285 (87.4) | 234 (80.4) | 0.017 |
| Number of 3-T Scans, n(%) | 1,045 (60.5) | 580 (65.8) | 465 (54.9) | <0.001 |
| Intracranial Volume, mean(SD) | 1397.8 (143.2) | 1305.7 (106.4) | 1488.3 (114.9) | <0.001 |
| Follow-up Time, mean (SD) | 3.5 (4.7) | 3.6 (5.0) | 3.4 (4.5) | 0.409 |
| Follow-up Time for those with ≥2 visits, mean (SD) | 4.1 (1.9) | 4.3 (5.2) | 3.9 (4.6) | 0.192 |
| Number of Follow-up Visits, n(%) | 0.786 | |||
| 1 | 617 (100.0) | 326 (100.0) | 291 (100.0) | |
| 2 | 368 (59.6) | 189 (58.0) | 179 (61.5) | |
| 3 | 172 (27.9) | 89 (27.3) | 83 (28.5) | |
| 4 | 101 (16.4) | 45 (13.8) | 56 (19.2) | |
| 5 | 83 (13.5) | 36 (11.0) | 47 (16.2) | |
| 6 | 73 (11.8) | 33 (10.1) | 40 (13.7) | |
| 7 | 67 (10.9) | 31 (9.5) | 36 (12.4) | |
| 8 | 59 (9.6) | 28 (8.6) | 31 (10.7) | |
| 9 | 49 (7.9) | 24 (7.4) | 25 (8.6) | |
| 10 | 42 (6.8) | 22 (6.7) | 20 (6.9) | |
| 11 | 34 (5.5) | 19 (5.8) | 15 (5.2) | |
| 12+ | 63 (10.2) | 39 (12.0) | 24 (8.2) |
SD – standard deviation, ICV – intracranial volume, CHF – congestive heart failure, HDL – high-density lipoprotein, LDL – low – density lipoprotein Note: We used t-tests for continuous variables and chi-squared tests for categorical variables. There were 142 (23.0%) missing for APOE e4 genotype, 3 (0.5%) missing for baseline elevated cholesterol, 4 (0.7%) missing for antihypertensive medications, and 3 (0.5%) missing for baseline obesity status.