Table 3.
Association between serum levels of trace elements and bone mineral density.
| Median concentration | Participants (n) | Normal BMD (%) | Unadjusted OR (95% CI) | P values | Multivariable-adjusted OR (95% CI) | P | |
|---|---|---|---|---|---|---|---|
| Mg (mmol/L) | |||||||
| T1 ≤ 1.45 (lowest) | 1.35 | 809 | 23.0 | 1.00 (reference) | – | 1.00 (reference) | – |
| T2 1.46–1.64 | 1.55 | 808 | 26.6 | 1.21 (0.97, 1.52) | 0.09 | 1.18 (0.92, 1.52) | 0.18 |
| T3 ≥ 1.65 (highest) | 1.75 | 795 | 28.9 | 1.36 (1.09, 1.71) | 0.01 | 1.30 (1.02, 1.67) | 0.04 |
| P for trend | 0.01 | 0.04 | |||||
| Fe (mmol/L) | |||||||
| T1 ≤ 7.73 (lowest) | 7.43 | 800 | 20.3 | 1.00 (reference) | – | 1.00 (reference) | – |
| T2 7.74–8.59 | 8.13 | 809 | 24.5 | 1.28 (1.01, 1.62) | 0.04 | 1.04 (0.81, 1.35) | 0.75 |
| T3 ≥ 8.60 (highest) | 9.22 | 803 | 33.7 | 2.01 (1.60, 2.52) | < 0.005 | 1.43 (1.11, 1.84) | 0.01 |
| P for trend | < 0.005 | < 0.005 | |||||
| Pb (μg/L) | |||||||
| T1 ≤ 30.00 (lowest) | 24.60 | 813 | 20.9 | 1.00 (reference) | – | 1.00 (reference) | – |
| T2 30.1–36.6 | 33.65 | 796 | 25.3 | 1.28 (1.01, 1.61) | 0.04 | 1.15 (0.89, 1.48) | 0.29 |
| T3 ≥ 36.70 (highest) | 40.00 | 803 | 32.4 | 1.81 (1.45, 2.27) | < 0.005 | 1.13 (0.88, 1.45) | 0.36 |
| P for trend | < 0.005 | 0.34 | |||||
| Cu (μmol/L) | |||||||
| T1 ≤ 20.49 (lowest) | 18.27 | 495 | 23.0 | 1.00 (reference) | – | 1.00 (reference) | – |
| T2 20.53–23.56 | 22.19 | 466 | 24.7 | 1.10 (0.81, 1.47) | 0.55 | 1.07 (0.77, 1.48) | 0.79 |
| T3 23.61–26.35 | 25.12 | 496 | 25.6 | 1.15 (0.86, 1.54) | 0.35 | 1.07 (0.78, 1.48) | 0.66 |
| T4 26.36–29.75 | 28.30 | 472 | 27.1 | 1.24 (0.93, 1.67) | 0.14 | 1.11 (0.80, 1.53) | 0.53 |
| T5 ≥ 29.76 (highest) | 32.20 | 483 | 30.4 | 1.46 (1.01, 1.95) | 0.01 | 1.42 (1.04, 1.94) | 0.03 |
| P for trend | 0.01 | 0.03 | |||||
| Zn (μg/dL) | |||||||
| T1 ≤ 71.06 (lowest) | 63.05 | 481 | 17.3 | 1.00 (reference) | – | 1.00 (reference) | – |
| T2 71.08–80.11 | 75.79 | 483 | 22.6 | 1.40 (1.02, 1.92) | 0.04 | 1.32 (0.94, 1.86) | 0.11 |
| T3 80.12–86.67 | 83.32 | 482 | 28.4 | 1.90 (1.40, 2.59) | < 0.005 | 1.46 (1.05, 2.04) | 0.03 |
| T4 86.71–94.21 | 90.24 | 481 | 26.6 | 1.74 (1.27, 2.37) | < 0.005 | 1.28 (0.92, 1.80) | 0.15 |
| T5 ≥ 94.25 (highest) | 98.28 | 485 | 35.9 | 2.68 (1.99, 3.62) | < 0.005 | 1.48 (1.06, 2.06) | 0.02 |
| P for trend | < 0.005 | 0.04 | |||||
Multivariable model was adjusted for age (continuous data), gender (male, female), body length (continuous data), weight (continuous data) and head circumference (continuous data).
n number, BMD bone mineral density, Mg magnesium, Fe iron, Pb lead, Cu copper, Zn zinc, OR odds ratio, CI confidence interval.