Table 2.
Multilevel-adjusted associations of SF, transferrin, and Hb levels with SUA concentrations in Chinese adult population (n = 7946).
| SUA, mg/dL | β (95% CI) 1 | Adjust β (95% CI) 2 | Adjust β (95% CI) 3 | ||
|---|---|---|---|---|---|
| SF | Q1 | 4.26 ± 1.25 | Ref. | Ref. | Ref. |
| Q2 | 4.91 ± 1.46 | 0.658 (0.555, 0.761) | 0.310 (0.209, 0.411) | 0.267 (0.167, 0.367) | |
| Q3 | 5.46 ± 1.57 | 1.202 (1.099, 1.305) | 0.587 (0.481, 0.693) | 0.529 (0.423, 0.635) | |
| Q4 | 6.10 ± 2.19 | 1.842 (1.739, 1.945) | 0.991 (0.879, 1.103) | 0.899 (0.788, 1.010) | |
| p-trend | <0.001 | <0.001 | <0.001 | <0.001 | |
| Transferrin | Q1 | 5.05 ± 1.54 | Ref. | Ref. | Ref. |
| Q2 | 5.15 ± 1.61 | 0.094 (−0.017, 0.205) | 0.196 (0.098, 0.294) | 0.208 (0.112, 0.304) | |
| Q3 | 5.27 ± 1.73 | 0.216 (0.105, 0.327) | 0.334 (0.235, 0.433) | 0.351 (0.254, 0.448) | |
| Q4 | 5.26 ± 2.19 | 0.209 (0.098, 0.320) | 0.457 (0.357, 0.557) | 0.488 (0.389, 0.587) | |
| p-trend | <0.001 | <0.001 | <0.001 | <0.001 | |
| Hb | Q1 | 4.58 ± 1.50 | Ref. | Ref. | Ref. |
| Q2 | 4.79 ± 1.47 | 0.213 (0.109, 0.317) | 0.046 (−0.051, 0.143) | 0.029 (−0.066, 0.124) | |
| Q3 | 5.45 ± 1.73 | 0.876 (0.769, 0.983) | 0.148 (0.039, 0.257) | 0.114 (0.006, 0.222) | |
| Q4 | 5.98 ± 2.08 | 1.402 (1.294, 1.510) | 0.388 (0.269, 0.507) | 0.353 (0.235, 0.471) | |
| p-trend | <0.001 | <0.001 | <0.001 | <0.001 |
SUA, serum uric acid; CI, confidence interval; SF, serum ferritin; Ref., reference; Hb, hemoglobin; BMI, body mass index; E%, percentage of energy; Hs-CRP, high-sensitivity C-reactive protein. All of the models were constructed by using multilevel (four levels) mixed-effects linear regression with the iterative generalized least-squares method. The medians (interquartile ranges) or means ± standard deviation for quartiles of SF, transferrin, and Hb were as follows—SF: 20.3 (11.3, 29.3), 58.0 (48.7, 67.8), 104.5 (90.7, 121.7), and 237.8 (174.6, 446.5) μg/L; transferrin: 2.3 ± 0.3, 2.7 ± 0.1, 3.0 ± 0.1, 3.6 ± 0.4 g/L; Hb: 116.9 ± 11.8, 135.0 ± 3.8, 147.8 ± 3.7, 167.8 ± 13.9 g/L. 1 Original model without any adjustments. 2 Adjusted for age, gender (male or female), nationality (Han or others), education (≤6 years, 6.1–9.0 years, or >9 years), smoking status (current or not current), alcohol consumption (yes or no), BMI (<18.5 kg/m2, 18.5–24.9 kg/m2, 25.0–29.9 kg/m2, or ≥30 kg/m2), and physical activity (quartile). 3 Adjusted as for model 2 plus total energy intake (quartile), protein intake (quartile), fat intake (quartile), carbohydrate (E%) (quartile), protein (E%) (quartile), fat (E%) (quartile), and inflammation status (hs-CRP levels < 1 mg/L, 1–3 mg/L or 4–10 mg/L).