Table 1.
Characteristics of Study Participants by Race and Visita
| Overall |
Whites |
Blacks |
|||||
|---|---|---|---|---|---|---|---|
| Visit 2 | Visit 3 | Visit 2 | Visit 3 | Visit 2 | Visit 3 | Brain MRI Visit | |
| n | 13 112 | 1764 | 9890 | 888 | 3222 | 876 | 472 |
| 25(OH)D, nmol/L | 60.6 (21.4) | 53.6 (20.6) | 65.0 (20.8) | 63.5 (19.9) | 47.0 (16.8) | 43.5 (15.8) | 53.2 (17.5) |
| Supplement use with vitamin D, n, % | 2516 (19.2) | 507 (28.7) | 2053 (20.8) | 286 (32.2) | 463 (14.4) | 221 (25.2) | 218 (46.0) |
| Deplete (25[OH]D <50 nmol/L), n, % | 4274 (32.6) | 833 (47.2) | 2290 (23.2) | 223 (25.1) | 1984 (61.6) | 610 (69.6) | 220 (46.6) |
| Age, y | 56.9 (5.7) | 62.4 (4.5) | 57.1 (5.7) | 63.2 (4.4) | 56.2 (5.8) | 61.7 (4.5) | 72.2 (4.1) |
| Male, n, % | 5697 (43.4) | 710 (40.2) | 4545 (46.0) | 389 (43.8) | 1152 (35.8) | 321 (36.6) | 163 (34.5) |
| Center, n, % | |||||||
| Forsyth County, North Carolina | 3326 (25.4) | 995 (56.4) | 2981 (30.1) | 888 (100.0) | 345 (10.7) | 107 (12.2) | 0 |
| Jackson, Mississippi | 2831 (21.6) | 769 (43.6) | 0 | 0 | 2831 (87.9) | 769 (87.8) | 472 (100.0) |
| Minneapolis, Minnesota | 3548 (27.1) | 0 | 3531 (35.7) | 0 | 17 (0.5) | 0 | 0 |
| Washington County, Maryland | 3407 (26.0) | 0 | 3378 (34.2) | 0 | 29 (0.9) | 0 | 0 |
| Education, n, %b | |||||||
| <High school | 2804 (21.4) | 483 (27.4) | 1548 (15.7) | 130 (14.6) | 1256 (39.1) | 353 (40.4) | 172 (36.6) |
| High school or vocational school | 5471 (41.8) | 603 (34.2) | 4551 (46.1) | 384 (43.2) | 920 (28.6) | 219 (25.1) | 109 (23.2) |
| College, graduate, or professional school | 4816 (36.8) | 676 (38.4) | 3779 (38.3) | 374 (42.1) | 1037 (32.3) | 302 (34.6) | 189 (40.2) |
| Smoking status, n, % | |||||||
| Never | 5284 (40.4) | 786 (44.7) | 3817 (38.6) | 358 (40.4) | 1467 (45.8) | 428 (49.0) | 281 (60.3) |
| Former | 4929 (37.7) | 653 (37.1) | 4007 (40.5) | 369 (41.6) | 922 (28.8) | 284 (32.5) | 157 (33.7) |
| Current | 2877 (22.0) | 321 (18.2) | 2064 (20.9) | 160 (18.0) | 813 (25.4) | 161 (18.4) | 28 (6.0) |
| Current alcohol consumption, n, % | |||||||
| No | 5701 (43.6) | 1100 (62.5) | 3583 (36.2) | 469 (52.8) | 2118 (66.1) | 631 (72.3) | 365 (77.3) |
| Yes | 7388 (56.4) | 661 (37.5) | 6304 (63.8) | 419 (47.2) | 1084 (33.9) | 242 (27.7) | 107 (22.7) |
| Physical activity indexc | 2.4 (0.8) | 2.5 (0.8) | 2.5 (0.8) | 2.7 (0.8) | 2.2 (0.7) | 2.4 (0.7) | NA |
| BMI, kg/m2 | 27.9 (5.4) | 28.0 (5.2) | 27.3 (4.9) | 26.5 (4.6) | 30.0 (6.2) | 29.5 (5.3) | 30.5 (5.2) |
| Diabetes, n, % | 1923 (14.7) | 324 (18.4) | 1138 (11.5) | 99 (11.1) | 785 (24.6) | 225 (25.8) | NA |
| Hypertension, n, % | 4680 (35.8) | 851 (48.5) | 2906 (29.4) | 295 (33.3) | 1774 (55.4) | 556 (64.1) | 372 (82.7) |
| Total cholesterol, mmol/L | 5.4 (1.0) | 5.4 (1.0) | 5.4 (1.0) | 5.4 (0.9) | 5.4 (1.1) | 5.4 (1.0) | NA |
| HDL, mmol/L | 1.3 (0.4) | 1.4 (0.5) | 1.3 (0.4) | 1.4 (0.5) | 1.4 (0.4) | 1.4 (0.5) | NA |
| LDL, mmol/L | 3.5 (1.0) | 3.3 (0.9) | 3.4 (0.9) | 3.2 (0.8) | 3.5 (1.0) | 3.3 (1.0) | NA |
| Triglycerides, mmol/L | 1.5 (1.0) | 1.5 (1.0) | 1.6 (1.0) | 1.7 (1.1) | 1.3 (0.8) | 1.3 (0.7) | NA |
| PTH, pmol/L | 4.5 (2.5) | 4.9 (3.3) | 4.2 (1.6) | 4.4 (2.7) | 5.3 (4.2) | 5.4 (3.7) | NA |
| Calcium, mmol/L | 2.3 (0.1) | 2.4 (0.1) | 2.3 (0.1) | 2.3 (0.1) | 2.4 (0.1) | 2.4 (0.1) | NA |
| Phosphate, mmol/L | 1.1 (0.2) | 1.1 (0.2) | 1.1 (0.2) | 1.1 (0.2) | 1.2 (0.2) | 1.1 (0.2) | NA |
| eGFR, mL/min per 1.73 m2 | 96.3 (15.8) | NA | 94.0 (13.1) | NA | 103.3 (20.6) | NA | NA |
| eGFR categories, mL/min per 1.73 m2 | |||||||
| <30 | 30 (0.2) | NA | 4 (0.0) | NA | 26 (0.8) | NA | NA |
| 30 to <60 | 247 (1.9) | NA | 168 (1.7) | NA | 79 (2.5) | NA | NA |
| 60 to <90 | 3330 (25.4) | NA | 2697 (27.3) | NA | 633 (19.6) | NA | NA |
| ≥90 | 9505 (72.5) | NA | 7021 (71.0) | NA | 2484 (77.1) | NA | NA |
Abbreviations: LDL, low-density lipoprotein; NA, not available.
a
Data are means (SD) or number (percentage).
b
Education information for visits 2 and 3 is derived from visit 1 (1987–1989).
c
Physical activity index for visit 2 is derived from visit 1 (1987–1989).