Table 2.
Sample characteristics according to quartiles of 25(OH)D and race [Mean (SE mean) or % distribution]
| Serum 25(OH)D Quartile (ng/mL) | |||||
|---|---|---|---|---|---|
| Whites (N=5001) | ptrend | ||||
| 1(<22.0) | 2(22.0–28.5) | 3(28.6–35.9) | 4(≥36) | ||
| 25(OH)D level, ng/mL | 17.2(0.1) | 25.4(0.1) | 32.1(0.1) | 44.7(0.3) | |
| Unweighted N | 1208 | 1239 | 1265 | 1289 | |
| Age [years] | 53.7(0.8) | 51.4(0.7) | 49.4(0.7) | 46.9(0.7) | <0.0001 |
| Women | 66.5 | 53.3 | 50.9 | 44.1 | <0.0001 |
| BMI [kg/m2] | 28.2(0.3) | 27.3(0.2) | 26.5(0.21) | 25.4(0.2) | <0.0001 |
| Physical activity [times/month] | 16.7(1.1) | 21.7(1.0) | 25.0(1.0) | 30.8(1.3) | <0.0001 |
| CRP [mg/dL] | 0.48(0.02) | 0.41(0.02) | 0.37(0.02) | 0.35(0.01) | <0.0001 |
| GFR [ml/min per 1.73 m2] | 91.8(1.0) | 93.9(0.9) | 93.7(0.9) | 93.8(0.9) | 0.14 |
| Diabetes | 8.9 | 6.9 | 4.4 | 4.1 | <0.0001 |
| Hypertension | 35.0 | 29.3 | 26.2 | 22.0 | <0.0001 |
| Hypercholesterolemia | 31.2 | 24.9 | 23.1 | 22.3 | 0.0002 |
|
| |||||
| Blacks (N=2980) | |||||
| 1(<13.6) | 2(13.6–17.9) | 3(18.0–24.1) | 4(≥24.2) | ||
|
| |||||
| 25(OH)D level, ng/mL2 | 10.6(0.1) | 15.8(0.04) | 20.8(0.1) | 31.4(0.4) | |
| Unweighted N | 742 | 741 | 757 | 740 | |
| Age [years] | 44.8(0.6) | 46.6(0.7) | 46.8(0.7) | 48.4(0.8) | 0.0006 |
| Women | 69.3 | 59.2 | 48.7 | 47.4 | <0.0001 |
| BMI [kg/m2] | 28.9(0.3) | 28.7(0.4) | 28.0(0.3) | 27.3(0.3) | <0.0001 |
| Physical activity [times/month] | 16.1(0.9) | 18.3(1.1) | 23.4(1.4) | 26.0(1.5) | <0.0001 |
| CRP [mg/dL] | 0.56(0.03) | 0.55(0.03) | 0.51(0.04) | 0.47(0.02) | 0.021 |
| GFR [ml/min per 1.73 m2] | 111.3(1.4) | 106.6(1.3) | 106.4(1.1) | 103.1(1.2) | <0.0001 |
| Diabetes | 7.4 | 9.6 | 9.4 | 9.5 | 0.22 |
| Hypertension | 31.9 | 35.4 | 37.3 | 36.8 | 0.08 |
| Hypercholesterolemia | 15.2 | 20.4 | 21.1 | 22.4 | 0.008 |