Table 1.
Participant characteristics at baseline (2009 to 2010), according to sex and the presence or absence of iron overload
| Characteristic | Women (n=3,131) |
Men (n=2,648) |
|||||||
|---|---|---|---|---|---|---|---|---|---|
| Non-iron overload (n=2,916) | Iron overload (n=215) | P value | SMD | Non-iron overload (n=2,196) | Iron overload (n=452) | P value | SMD | ||
| Age, yr | 50.14±14.03 | 62.03±10.54 | <0.001 | 0.958 | 51.30±14.83 | 49.01±13.03 | 0.002 | 0.164 | |
| Physical examinations | |||||||||
| Height, cm | 155.52±6.37 | 153.73±6.40 | <0.001 | 0.280 | 166.38±6.68 | 166.78±6.65 | 0.241 | 0.061 | |
| Weight, kg | 56.54±9.54 | 57.81±10.02 | 0.061 | 0.129 | 63.77±11.18 | 68.60±11.13 | <0.001 | 0.433 | |
| BMI, kg/m2 | 23.34±3.46 | 24.37±3.46 | <0.001 | 0.299 | 22.96±3.32 | 24.60±3.31 | <0.001 | 0.493 | |
| Systolic pressure, mm Hg | 122.82±19.51 | 131.97±21.12 | <0.001 | 0.450 | 125.74±17.65 | 125.91±15.86 | 0.850 | 0.010 | |
| Diastolic pressure, mm Hg | 78.81±11.00 | 81.37±11.73 | 0.001 | 0.225 | 81.49±10.96 | 83.40±10.94 | 0.001 | 0.174 | |
| Biological | |||||||||
| Glucose, mmol/L | 5.08 (4.71–5.54) | 5.39 (5.01–6.17) | <0.001 | 0.457 | 5.09 (4.70–5.58) | 5.36 (4.89–5.89) | <0.001 | 0.307 | |
| HbA1c, mmol/L | 5.50 (5.20–5.80) | 5.70 (5.40–6.10) | <0.001 | 0.345 | 5.50 (5.20–5.80) | 5.60 (5.20–6.00) | <0.001 | 0.225 | |
| INS, μIU/mL | 10.45 (7.53–14.86) | 12.44 (8.49–18.73) | <0.001 | 0.102 | 10.05 (6.92–14.48) | 11.44 (7.75–16.65) | <0.001 | 0.056 | |
| IR | |||||||||
| No | 1,768 (60.6) | 106 (49.3) | 0.001 | 0.229 | 1,398 (63.7) | 242 (53.5) | <0.001 | 0.207 | |
| Yes | 1,148 (39.4) | 109 (50.7) | 798 (36.3) | 210 (46.5) | |||||
| Hemoglobin, g/L | 132.00 (122.00–140.00) | 133.00 (125.00–142.00) | 0.095 | 0.059 | 151.00 (141.00–162.00) | 155.00 (146.00–165.00) | <0.001 | 0.242 | |
| HS-CRP, mg/L | 1.00 (0.00–2.00) | 2.00 (1.00–4.00) | <0.001 | 0.174 | 1.00 (1.00–2.00) | 1.00 (1.00–3.00) | <0.001 | 0.115 | |
| FET, ng/mL | 46.38 (22.15–81.95) | 301.87 (235.48–499.30) | <0.001 | 2.217 | 105.24 (66.56–155.58) | 556.36 (416.61–787.13) | <0.001 | 2.628 | |
| TRF, mg/gL | 291.00 (259.00–329.00) | 274.00 (246.00–308.00) | <0.001 | 0.380 | 277.00 (246.00–311.00) | 274.00 (245.00–311.25) | 0.588 | 0.001 | |
| Apo-A, g/L | 1.12 (0.98–1.31) | 1.14 (0.96–1.36) | 0.549 | 0.048 | 1.09 (0.93–1.30) | 1.03 (0.88–1.23) | <0.001 | 0.181 | |
| Apo-B, g/L | 0.88 (0.73–1.08) | 1.06 (0.85–1.25) | <0.001 | 0.564 | 0.88 (0.72–1.05) | 0.96 (0.81–1.15) | <0.001 | 0.334 | |
| LDL-C, mmol/L | 2.94 (2.40–3.60) | 3.26 (2.60–4.14) | <0.001 | 0.302 | 2.88 (2.33–3.45) | 2.94 (2.26–3.65) | 0.300 | 0.053 | |
| HDL-C, mmol/L | 1.45 (1.24–1.70) | 1.39 (1.15–1.61) | 0.004 | 0.178 | 1.36 (1.15–1.62) | 1.23 (1.02–1.50) | <0.001 | 0.288 | |
| LP-A, mg/dL | 83.00 (44.00–179.00) | 93.00 (52.50–200.00) | 0.151 | 0.108 | 75.00 (38.00–161.25) | 64.00 (30.75–134.75) | 0.001 | 0.083 | |
| TG, mmol/L | 1.20 (0.83–1.76) | 1.70 (1.21–2.71) | <0.001 | 0.542 | 1.19 (0.81–1.86) | 1.84 (1.17–2.89) | <0.001 | 0.508 | |
| TC, mmol/L | 4.80 (4.18–5.52) | 5.41 (4.65–6.17) | <0.001 | 0.501 | 4.72 (4.16–5.32) | 4.95 (4.38–5.81) | <0.001 | 0.337 | |
| ALB, g/L | 46.90 (45.00–49.10) | 47.40 (45.55–49.75) | 0.011 | 0.183 | 47.40 (45.20–49.70) | 48.20 (46.00–50.40) | <0.001 | 0.197 | |
| ALT, U/L | 16.00 (12.00–23.00) | 22.00 (15.00–34.50) | <0.001 | 0.460 | 20.00 (15.00–28.00) | 27.00 (18.00–42.00) | <0.001 | 0.448 | |
| TP, g/L | 77.90 (74.70–81.30) | 77.80 (75.20–82.10) | 0.311 | 0.081 | 76.50 (73.10–79.80) | 76.30 (73.20–79.60) | 0.564 | 0.040 | |
| Diet | |||||||||
| Calorie, kcal | 1,994.50±605.06 | 1,935.67±586.26 | 0.168 | 0.099 | 2,366.86±691.93 | 2,357.75±678.95 | 0.798 | 0.013 | |
| Carbohydrate, g | 278.29±94.09 | 267.27±90.88 | 0.097 | 0.119 | 327.23±107.88 | 318.21±107.60 | 0.106 | 0.084 | |
| Fat, g | 70.05±38.54 | 68.72±35.48 | 0.626 | 0.036 | 80.58±39.30 | 81.97±42.67 | 0.500 | 0.034 | |
| Protein, g | 61.77±21.00 | 61.56±21.58 | 0.884 | 0.010 | 72.57±24.80 | 74.10±23.97 | 0.230 | 0.063 | |
| Behavioral | |||||||||
| Smoke | |||||||||
| No | 2,837 (97.3) | 204 (94.9) | 0.054 | 0.124 | 782 (35.6) | 175 (38.7) | 0.217 | 0.064 | |
| Yes | 79 (2.7) | 11 (5.1) | 1,414 (64.4) | 277 (61.3) | |||||
| Alcohol | |||||||||
| No | 2,662 (91.3) | 198 (92.1) | 0.802 | 0.029 | 868 (39.5) | 140 (31.0) | 0.001 | 0.180 | |
| Yes | 254 (8.7) | 17 (7.9) | 1,328 (60.5) | 312 (69.0) | |||||
Values are presented as mean±standard deviation, median (interquartile range), or number (%).
SMD, standard mean difference; HbA1c, glycosylated hemoglobin; INS, insulin; IR, insulin resistance; HS-CRP, high-sensitivity C-reactive protein; FET, ferritin; TRF, transferrin; Apo, apolipoprotein; LDL-C, low-density lipoprotein cholesterol; HDL-C, high-density lipoprotein cholesterol; LP-A, lipoprotein (a); TG, triglyceride; TC, total cholesterol; ALB, albumin; ALT, alanine aminotransferase; TP, total protein.