Table 3. Lead Biomarkers and Serum Iron Indices by HFE Genotypes [Mean ±SD or N or M (P25, P75)].
| All | HH | HD or DD | |||||
| Na | Mean ±SD or M (P25, P75) | N | Mean ±SD or M (P25, P75) | N | Mean ±SD or M (P25, P75) | P | |
| BPb (µg/L) | 748 | 345.90±157.95 | 705 | 344.75±158.70 | 43 | 364.87±145.52 | 0.418 |
| UPb (µg/L) | 727 | 32.00(12.300,71.00) | 686 | 31.00(12.00,71.00) | 41 | 40.00(18.00,77.00) | 0.536 |
| ZPP(µg/gHb) | 757 | 5.60(3.00,10.20) | 714 | 5.70(3.00,10.33) | 43 | 4.90(2.80,9.40) | 0.406 |
| sFe (µmol/L) | 769 | 20.30±7.98 | 724 | 20.27±7.96 | 45 | 20.72±8.31 | 0.728 |
| UIBC(µmol/L) | 768 | 37.45(30.60,46.38) | 723 | 37.80(30.90,46.80) | 45 | 33.40(26.15, 42.25) | 0.012* |
| TIBC (µmol/L) | 768 | 57.43(52.40,63.87) | 723 | 57.90(52.55,64.18) | 45 | 54.85(49.11, 60.05) | 0.008** |
| Tf (g/L) | 768 | 2.72(2.44,3.04) | 723 | 2.74(2.46,3.05) | 45 | 2.54(2.23, 2.85) | 0.005** |
| TfS (%) | 768 | 33.41(24.47,44.09) | 723 | 33.13(24.41,43.57) | 45 | 37.19(25.47, 47.17) | 0.195 |
| sFn (µg/L) | 768 | 129.00(66.08,214.00) | 723 | 129.00(65.80,214.00) | 45 | 130.00(66.95, 227.00) | 0.983 |
| sTfR(mg/L) | 755 | 1.31(1.14,1.55) | 710 | 1.31(1.14,1.55) | 45 | 1.34(1.15, 1.54) | 0.844 |
| BIC(mg/kg) | 753 | 39.91(37.53,41.71) | 708 | 39.90(37.49,41.75) | 45 | 40.03(37.77, 41.64) | 0.853 |
| Hb (g/L) | 762 | 135.8±16.3 | 717 | 135.7±16.3 | 45 | 137.0±15.8 | 0.606 |
Abbreviations: BPb, blood lead; UPb, urine lead; ZPP, zinc protoporphyrin; sFe, serum iron; UIBC, unsaturated iron-binding capacity; TIBC, total iron binding capacity; Tf, transferrin; TfS, serum transferrin saturation; sFn, serum ferritin; sTfR, soluble transferrin receptor; BIC, body iron content; Hb, haemoglobin; HH, wild-type; HD, H63D heterozygous variant; DD, H63D homozygous variant.
*(**) p<0.05 (0.01) compared with HH (student's t-test or nonparametric test).
a
Because of missing data, the numbers do not equal 771.
Results were expressed as the mean ± SD when continuous variables followed a normal distribution.
Results were expressed as M (P25, P75) when continuous variables did not follow a normal distribution.