Table 2.
Characteristics of the study population by serum selenium quintile.
| Quintile of serum selenium (interval in µg/L) | ||||||
|---|---|---|---|---|---|---|
| 1st < 122 |
2nd 122 – 131 |
3rd 132 – 139 |
4th 140 – 149 |
5th ≥ 150 |
p trend | |
| N | 504 | 570 | 524 | 481 | 559 | |
| Age (years) | 56.6 | 56.3 | 57.2 | 55.4 | 57.7 | 0.02 |
| Gender (% female) | 64.3 | 57.9 | 49.8 | 43.3 | 44.4 | <0.001 |
| Race | ||||||
| Non-Hispanic White (%) | 76.5 | 75.6 | 76.6 | 82.3 | 83.1 | 0.03 |
| Non-Hispanic Black (%) | 15.3 | 10.9 | 10.3 | 6.3 | 5.3 | 0.004 |
| Mexican American (%) | 2.3 | 5.4 | 5.8 | 4.6 | 6.1 | 0.04 |
| Other (%) | 5.9 | 8.1 | 7.2 | 6.9 | 5.4 | 0.73 |
| Education (% High school) | 77.1 | 79.6 | 82.1 | 84.2 | 83.6 | 0.12 |
| Body Mass Index (kg/m2) | 28.6 | 28.7 | 28.7 | 28.6 | 28.0 | 0.05 |
| Current smoker (%) | 33.4 | 20.6 | 18.5 | 20.7 | 13.7 | <0.001 |
| Dietary Supplements (%) | 54.6 | 57.5 | 68.9 | 61.4 | 69.2 | 0.001 |
| Selenium (µg/L) | 113.1 | 126.7 | 135.2 | 144.4 | 163.7 | - |
Values are survey weighted means or percentages for continuous or categorical variables, respectively.