Table 3. The association between dietary selenium intake and bone mineral density by different age and sex.
| Dietary selenium intake (quintile) | Age <50 | Age ≥50 | Male | Female | |||||||
|---|---|---|---|---|---|---|---|---|---|---|---|
| β (95% CI) | P value | β (95% CI) | P value | β (95% CI) | P value | β (95% CI) | P value | ||||
| Total femur, gm/cm2 | |||||||||||
| Q1 | Reference | Reference | Reference | Reference | |||||||
| Q2 | −0.002 (−0.008, 0.005) | 0.641 | 0.013 (0.004, 0.022) | 0.003 | 0.006 (−0.003, 0.015) | 0.186 | 0.002 (−0.005, 0.008) | 0.620 | |||
| Q3 | 0.004 (−0.003, 0.011) | 0.221 | 0.013 (0.004, 0.022) | 0.005 | 0.005 (−0.004, 0.014) | 0.260 | 0.006 (−0.001, 0.013) | 0.082 | |||
| Q4 | 0.010 (0.003, 0.018) | 0.005 | 0.017 (0.008, 0.027) | <0.001 | 0.010 (0.001, 0.019) | 0.029 | 0.012 (0.005, 0.020) | 0.001 | |||
| Q5 | 0.015 (0.007, 0.022) | <0.001 | 0.020 (0.009, 0.030) | <0.001 | 0.016 (0.007, 0.025) | <0.001 | 0.004 (−0.005, 0.013) | 0.356 | |||
| P trend | <0.001 | <0.001 | <0.001 | 0.012 | |||||||
| Femur neck, gm/cm2 | |||||||||||
| Q1 | Reference | Reference | Reference | Reference | |||||||
| Q2 | 0.000 (−0.007, 0.007) | 0.959 | 0.006 (−0.002, 0.014) | 0.156 | 0.002 (−0.006, 0.011) | 0.599 | 0.000 (−0.006, 0.006) | 0.960 | |||
| Q3 | 0.005 (−0.002, 0.012) | 0.158 | 0.009 (0.001, 0.018) | 0.031 | 0.002 (−0.006, 0.010) | 0.646 | 0.006 (−0.001, 0.012) | 0.095 | |||
| Q4 | 0.010 (0.002, 0.017) | 0.009 | 0.013 (0.005, 0.022) | 0.003 | 0.005 (−0.003, 0.014) | 0.205 | 0.010 (0.003, 0.017) | 0.005 | |||
| Q5 | 0.012 (0.004, 0.019) | 0.003 | 0.019 (0.009, 0.029) | <0.001 | 0.012 (0.004, 0.021) | 0.005 | 0.001 (−0.008, 0.009) | 0.869 | |||
| P trend | <0.001 | <0.001 | 0.002 | 0.055 | |||||||
| Trochanter, gm/cm2 | |||||||||||
| Q1 | Reference | Reference | Reference | Reference | |||||||
| Q2 | −0.002 (−0.008, 0.004) | 0.484 | 0.010 (0.002, 0.017) | 0.014 | 0.005 (−0.003, 0.013) | 0.221 | −0.000 (−0.006, 0.006) | 0.976 | |||
| Q3 | 0.001 (−0.006, 0.007) | 0.848 | 0.008 (−0.000, 0.016) | 0.059 | 0.002 (−0.006, 0.010) | 0.610 | 0.002 (−0.004, 0.008) | 0.559 | |||
| Q4 | 0.007 (0.001, 0.013) | 0.032 | 0.012 (0.004, 0.020) | 0.004 | 0.007 (−0.001, 0.015) | 0.078 | 0.008 (0.002, 0.015) | 0.013 | |||
| Q5 | 0.011 (0.004, 0.017) | 0.003 | 0.015 (0.005, 0.024) | 0.002 | 0.013 (0.004, 0.021) | 0.003 | 0.004 (−0.004, 0.012) | 0.344 | |||
| P trend | <0.001 | 0.003 | 0.002 | 0.034 | |||||||
| Intertrochanter, gm/cm2 | |||||||||||
| Q1 | Reference | Reference | Reference | Reference | |||||||
| Q2 | −0.002 (−0.010, 0.006) | 0.678 | 0.017 (0.007, 0.028) | 0.001 | 0.007 (−0.003, 0.018) | 0.163 | 0.004 (−0.004, 0.011) | 0.372 | |||
| Q3 | 0.007 (−0.001, 0.015) | 0.092 | 0.017 (0.007, 0.028) | 0.002 | 0.008 (−0.003, 0.018) | 0.144 | 0.010 (0.001, 0.018) | 0.024 | |||
| Q4 | 0.012 (0.004, 0.021) | 0.004 | 0.021 (0.010, 0.033) | <0.001 | 0.012 (0.001, 0.022) | 0.030 | 0.016 (0.007, 0.025) | <0.001 | |||
| Q5 | 0.018 (0.009, 0.027) | <0.001 | 0.022 (0.010, 0.035) | <0.001 | 0.018 (0.007, 0.029) | <0.001 | 0.006 (−0.005, 0.017) | 0.251 | |||
| P trend | <0.001 | <0.001 | <0.001 | 0.006 | |||||||
| Lumbar spine, gm/cm2 | |||||||||||
| Q1 | Reference | Reference | Reference | Reference | |||||||
| Q2 | −0.006 (−0.014, 0.001) | 0.072 | 0.005 (−0.008, 0.017) | 0.469 | −0.001 (−0.011, 0.010) | 0.887 | −0.004 (−0.012, 0.003) | 0.270 | |||
| Q3 | 0.002 (−0.006, 0.009) | 0.648 | 0.004 (−0.009, 0.017) | 0.555 | −0.000 (−0.010, 0.010) | 0.960 | 0.003 (−0.006, 0.011) | 0.502 | |||
| Q4 | 0.013 (0.005, 0.020) | 0.001 | 0.006 (−0.007, 0.020) | 0.370 | 0.006 (−0.004, 0.016) | 0.232 | 0.014 (0.005, 0.023) | 0.002 | |||
| Q5 | 0.017 (0.009, 0.025) | <0.001 | 0.003 (−0.012, 0.018) | 0.705 | 0.016 (0.005, 0.026) | 0.003 | −0.002 (−0.013, 0.009) | 0.759 | |||
| P trend | <0.001 | 0.642 | <0.001 | 0.055 | |||||||
Model 1: crude model; Model 2: adjusted for age and sex; Model 3: adjusted for age, sex (male and female), race (non-Hispanic white, non-Hispanic black, Mexican American, other race/ethnicity, or missing), education (under high school, high school, above high school, or missing), family income (under $20,000, $20,000–$55,000, $55,000 and over, or missing), body mass index (underweight, normal weight, overweight, obese, or missing), leisure time physical activity (<500 MET/week, 500–999 MET/week, ≥1,000 MET/week, or missing), smoking status (yes, no, or missing), alcohol use (yes, no, or missing), dietary fiber intake, calcium intake, diabetes (yes, no, or missing), and hypertension (yes, no, or missing). Q1, quintile 1; Q2–Q5, higher quintiles. MET, metabolic equivalent.