Table 2.
Vitamin D status by participant characteristics.
| Variable | 25(OH)D (ng/mL) | 25(OH)D < 20 ng/mL | 25(OH)D ≥ 20 ng/mL | |||
|---|---|---|---|---|---|---|
| N | Geometric mean (SE) | % (SE) | % (SE) | p-value | ||
| Total | 16.3 (1) | 71.7 (1) | 28.3 (1) | |||
| Age (years) | 19–29 | 1586 | 14.5 (1) | 22.8 (0.7) | 11 (1) | <0.01 |
| 30–39 | 2612 | 15.6 (1) | 22.5 (0.7) | 16.3 (1) | ||
| 40–49 | 2556 | 16.3 (1) | 22.3 (0.6) | 21.6 (1) | ||
| 50–59 | 2867 | 17.6 (1) | 16.7 (0.5) | 23.5 (1) | ||
| 60–69 | 2609 | 18.2 (1) | 8.7 (0.3) | 15.6 (0.7) | ||
| ≥70 | 2260 | 17.9 (1) | 7 (0.3) | 11.9 (0.6) | ||
| Sex | Male | 5869 | 17.3 (1) | 45.9 (0.6) | 60.8 (1) | <0.01 |
| Menstruating women | 4271 | 14.5 (1) | 35.7 (0.6) | 16.9 (1) | ||
| Menopausal women | 4350 | 17.1 (1) | 18.4 (0.5) | 22.3 (1) | ||
| Obesity | Underweight | 634 | 14.9 (1) | 5 (0.3) | 3.5 (0.4) | <0.01 |
| Normal | 9234 | 16.3 (1) | 63.3 (0.6) | 63.2 (1) | ||
| Overweight | 4585 | 16.6 (1) | 31.7 (0.7) | 33.3 (1) | ||
| Hypertension | No | 11043 | 16.1 (1) | 84.6 (0.5) | 78.3 (1) | <0.01 |
| Yes | 3447 | 17.5 (1) | 15.4 (0.5) | 21.7 (1) | ||
| Diabetes | No | 13241 | 16.2 (1) | 94.5 (0.3) | 91.5 (0.5) | <0.01 |
| Yes | 1249 | 17.6 (1) | 5.5 (0.3) | 8.5 (0.5) | ||
| Dyslipidemia | No | 12798 | 16.2 (1) | 92.2 (0.3) | 89.4 (0.5) | <0.01 |
| Yes | 1692 | 17.4 (1) | 7.8 (0.3) | 10.6 (0.5) | ||
| Smoking status | Non-smoker | 8829 | 15.8 (1) | 56.9 (0.6) | 45.9 (1) | <0.01 |
| Ex-smoker | 2967 | 17.6 (1) | 18.1 (0.5) | 27.2 (1) | ||
| Smoker | 2694 | 16.5 (1) | 25.1 (0.6) | 26.9 (1) | ||
| Alcohol consumption | None | 4186 | 16.2 (1) | 22.5 (0.6) | 22.2 (1) | <0.01 |
| Occasional (<2/week) | 7416 | 15.9 (1) | 56.7 (0.7) | 49.1 (1) | ||
| Frequent (≥2/week) | 2888 | 17.5 (1) | 20.9 (0.6) | 28.7 (1) | ||
| Regular exercise | No | 7694 | 16.1 (1) | 52.8 (0.7) | 48.3 (1) | <0.01 |
| Yes | 6796 | 16.6 (1) | 47.2 (0.7) | 51.7 (1) | ||
| Region of residence | Rural | 4844 | 17.8 (1) | 25.2 (1) | 40.7 (2) | <0.01 |
| Urban | 9646 | 15.7 (1) | 74.8 (1) | 59.3 (2) | ||
| Family income | <50th percentile | 6573 | 16.6 (1) | 41 (1) | 46.3 (1) | <0.01 |
| ≥50th percentile | 7917 | 16.2 (1) | 59 (1) | 53.7 (1) | ||
| Educational level | Middle school or lower | 5397 | 17.8 (1) | 23.8 (0.7) | 37.9 (1) | <0.01 |
| High school or higher | 9093 | 15.8 (1) | 76.2 (0.7) | 62.1 (1) | ||
| Occupation | White collar | 4604 | 15.8 (1) | 40.4 (1) | 30.5 (1) | <0.01 |
| Blue collar | 3887 | 17.8 (1) | 23.3 (0.7) | 38.4 (1) | ||
| Unemployed | 5999 | 15.8 (1) | 36.3 (0.6) | 31.2 (1) | ||
| Sleep duration (hours/day) | <6 | 2226 | 16.5 (1) | 12.9 (0.4) | 13.3 (0.7) | 0.48 |
| 6 to 9 | 11798 | 16.3 (1) | 83.5 (0.5) | 83.6 (0.7) | ||
| ≥10 | 466 | 15.7 (1) | 3.6 (0.2) | 3.1 (0.3) | ||
|
Exposure to sunlight (hours/day) |
<2 | 9173 | 15.8 (1) | 66.4 (1) | 53.5 (1) | <0.01 |
| ≥2 | 5317 | 17.3 (1) | 33.6 (1) | 46.5 (1) | ||
p-Values were calculated by Rao-Scott chi-square test.