Table 1.
Baseline (ARIC Visit 3, 1993–1995) characteristics by race-specific 25(OH)D tertiles (n=1,652).
| Highest 25(OH)D Tertile | Middle 25(OH)D Tertile | Lowest 25(OH)D Tertile | ||||
|---|---|---|---|---|---|---|
|
| ||||||
| Whites (≥28.3 ng/ml) (n=285) | Blacks (≥19.3 ng/ml) (n=267) | Whites (21.8– <28.3 ng/ml) (n=283) | Blacks (14.0– <19.3 ng/ml) (n=272) | Whites (<21.8 ng/ml) (n=284) | Blacks (<14.0 ng/ml) (n=261) | |
| Age (years), mean (SD) | 63.1 (4.3) | 62.2 (4.4) | 63.3 (4.5) | 61.4 (4.6) | 62.9 (4.4) | 61.0 (4.5) |
| Female, % | 48.4 | 52.4 | 53.7 | 63.2 | 66.9 | 78.2 |
| Study Site, % | ||||||
| Jackson, Mississippi | 0.0 | 88.8 | 0.0 | 86.8 | 0.0 | 85.4 |
| Forsyth County, North Carolina | 100.0 | 11.2 | 100.0 | 13.2 | 100.0 | 14.6 |
| Education, % | ||||||
| <High School | 14.4 | 43.8 | 15.2 | 37.1 | 11.6 | 35.3 |
| High School or Vocational School | 41.4 | 22.5 | 44.9 | 26.8 | 43.7 | 26.1 |
| College, Graduate, or Professional School | 44.2 | 33.7 | 39.9 | 36.1 | 44.7 | 38.7 |
| Family Income, % | ||||||
| <$35,000/year | 45.3 | 71.6 | 48.1 | 72.1 | 46.5 | 74.7 |
| ≥$35,000/year | 50.2 | 18.7 | 49.1 | 15.8 | 48.2 | 17.2 |
| Not Reported | 4.5 | 9.7 | 2.8 | 12.1 | 5.3 | 8.1 |
| Smoking Status, % | ||||||
| Never | 36.8 | 48.3 | 43.1 | 48.5 | 40.8 | 52.5 |
| Former | 48.8 | 36.3 | 41.0 | 34.6 | 34.9 | 27.6 |
| Current | 14.4 | 15.4 | 15.9 | 16.9 | 24.3 | 19.9 |
| Alcohol Consumption, % | ||||||
| Never | 30.2 | 40.5 | 34.3 | 46.3 | 38.4 | 46.4 |
| Former | 16.8 | 33.3 | 23.3 | 25.8 | 14.8 | 26.1 |
| Current | 53.0 | 26.2 | 42.4 | 27.9 | 46.8 | 27.6 |
| Physical activity index, mean (SD) | 3.0 (0.9) | 2.5 (0.8) | 2.6 (0.8) | 2.3 (0.7) | 2.4 (0.7) | 2.3 (0.7) |
| Body mass index (kg/m2), mean (SD) | 25.8 (4.0) | 29.2 (4.9) | 26.8 (4.6) | 29.6 (5.5) | 26.9 (5.1) | 30.0 (5.6) |
| Waist circumference (cm), mean (SD) | ||||||
| Men | 99.5 (11.2) | 98.6 (10.3) | 101.3 (10.2) | 97.7 (11.1) | 102.1 (12.4) | 99.9 (12.3) |
| Women | 89.4 (11.5) | 102.9 (15.1) | 95.5 (13.4) | 102.7 (14.8) | 96.0 (14.4) | 103.3 (14.0) |
| Diabetes, % | 6.3 | 24.0 | 12.4 | 27.4 | 13.4 | 24.5 |
| Hypertension, % | 30.6 | 60.9 | 36.5 | 60.9 | 31.0 | 67.2 |
| Total Cholesterol (mg/dl), mean (SD) | 209.0 (34.6) | 209.3 (40.9) | 210.1 (33.3) | 210.0 (39.9) | 208.5 (38.4) | 206.1 (39.9) |
| HDL (mg/dl), mean (SD) | 55.7 (21.3) | 56.6 (19.8) | 51.7 (18.6) | 56.1 (16.8) | 53.1 (19.8) | 56.0 (22.4) |
| LDL (mg/dl), mean (SD) | 125.0 (31.5) | 125.7 (36.5) | 126.7 (30.9) | 131.6 (37.6) | 124.5 (34.1) | 129.9 (38.7) |
| Triglycerides (mg/dl), mean (SD) | 142.6 (85.5) | 114.5 (60.6) | 162.8 (119.0) | 112.2 (59.2) | 151.5 (85.5) | 121.6 (70.7) |
| * Creatinine (mg/dl), mean (SD) | 1.16 (0.18) | 1.22 (0.23) | 1.12 (0.20) | 1.16 (0.26) | 1.09 (0.19) | 1.15 (0.36) |
| * Estimated GFR (ml/min), mean (SD) | 84.2 (12.6) | 91.4 (17.0) | 86.7 (13.2) | 96.2 (16.5) | 86.8 (13.0) | 95.1 (18.7) |
| PTH (pg/ml), mean (SD) | 37.0 (13.3) | 44.0 (18.2) | 40.6 (14.1) | 49.1 (23.3) | 47.3 (40.9) | 58.0 (37.0) |
| Calcium (mg/dl), mean (SD) | 9.4 (0.4) | 9.6 (0.4) | 9.4 (0.3) | 9.5 (0.4) | 9.4 (0.4) | 9.5 (0.5) |
| Phosphate (mg/dl), mean (SD) | 3.35 (0.52) | 3.45 (01) | 3.39 (0.48) | 3.51 (0.46) | 3.46 (0.57) | 3.51 (0.50) |
| Vitamin D Supplementation Use, % | 4.2 | 2.3 | 1.4 | 0.0 | 1.8 | 0.4 |
| C-reactive protein (mg/L), median (IQR) | 2.0 (0.9, 4.9) | 3.4 (1.4, 6.6) | 2.0 (1.2, 6.1) | 3.2 (1.3, 7.0) | 2.3 (1.0, 5.3) | 3.5 (1.4, 7.0) |
| Visit 3 Cognitive Test Scores | ||||||
| DWRT (words), mean (SD) | 6.79 (1.43) | 5.89 (1.72) | 6.77 (1.46) | 6.08 (1.76) | 6.81 (1.49) | 6.22 (1.78) |
| DSST (points), mean (SD) | 46.5 (11.2) | 27.6 (12.0) | 45.9 (10.6) | 29.2 (13.1) | 47.6 (11.6) | 31.2 (13.6) |
| WFT (words), mean (SD) | 34.4 (12.1) | 27.4 (13.3) | 32.7 (10.9) | 28.4 (14.2) | 35.3 (11.3) | 28.7 (13.6) |
Measured at ARIC Visit 2 (1990–1992).
Note: The following variables had missing data: diabetes (n=1), hypertension (n=9), total cholesterol (n=1), HDL cholesterol (n=1), LDL cholesterol (n=22), triglycerides (n=1), 10-year Framingham risk (n=137), 10-year risk of stroke (n=96), creatinine (n=18), estimated GFR (n=18), PTH (n=8), calcium (n=2), and C-reactive protein (n=209).
Abbreviations: 25(OH)D, 25-hydroxyvitamin D; DWRT, Delayed Word Recall Test; DSST, Digit Symbol Substitution Test; GFR, Glomerular Filtration Rate; HDL, high-density lipoprotein; IQR, inter-quartile range; LDL, low-density lipoprotein; PTH, parathyroid hormone; SD, standard deviation; WFT, Word Fluency Test.