Characteristics of the study population by quartiles of serum selenium levels
| Quartiles of serum selenium levels | |||||
|---|---|---|---|---|---|
| Q1 (N=213) (<71.4 µg/L) | Q2 (N=211) (71.4–86.7 µg/L) | Q3 (N=212) (86.8–104.5 µg/L) | Q4 (N=211) (>104.5 µg/L) | p Value | |
| Gender | 0.23 | ||||
| Male (%) | 152 (72.0) | 155 (73.5) | 146 (68.9) | 135 (64.0) | |
| Female (%) | 59 (28.0) | 56 (26.5) | 66 (31.3) | 76 (36.0) | |
| Age (years) | 62.7±10.4 | 62.7±9.6 | 64.9±9.6 | 65.2±9.6 | <0.01 |
| BMI (kg/m2) | 23.9±2.9 | 24.3±4.1 | 24.4±3.9 | 25.5±4.0 | <0.001 |
| WC (cm) | 82.7±8.6 | 83.4±9.8 | 84.2±10.4 | 86.9±10.0 | <0.001 |
| Systolic BP (mm Hg) | 126.6±17.2 | 126.6±14.0 | 128.8±15.5 | 130.8±14.7 | 0.01 |
| Diastolic BP (mm Hg) | 75.2±11.3 | 76.7±9.3 | 76.3±9.4 | 76.0±9.6 | 0.41 |
| TCHO (mmol/L) | 5.27±0.94 | 5.33±0.95 | 5.02±0.95 | 5.20±1.06 | <0.01 |
| TG (mmol/L) | 1.40±0.82 | 1.55±0.90 | 1.53±1.28 | 1.72±0.90 | <0.05 |
| HDL-C (mmol/L) | 1.35±0.33 | 1.36±0.32 | 1.31±0.32 | 1.32±0.38 | 0.25 |
| LDL-C (mmol/L) | 3.21±0.72 | 3.24±0.74 | 3.05±0.76 | 3.14±0.82 | 0.05 |
| Glu (mmol/L) | 5.79±1.27 | 5.95±1.48 | 6.14±1.72 | 6.78±2.14 | <0.001 |
| Insulin (U/mL) | 7.58±4.59 | 9.12±8.20 | 8.61±6.08 | 11.05±9.10 | <0.001 |
| HOMA-IR | 2.13±1.96 | 2.65±3.01 | 2.51±2.05 | 3.55±3.24 | <0.001 |
| Selenium (µg/L) | 62.0±6.8 | 79.0±4.6 | 95.6±5.4 | 116.3±9.1 | <0.001 |
| Current smoking (%) | 10 (4.7) | 10 (4.7) | 17 (8.0) | 26 (12.3) | <0.01 |
| Current drinking (%) | 14 (6.6) | 20 (9.5) | 13 (6.1) | 23 (10.9) | 0.22 |
| Exercise (hours/week) | 3.8±4.3 | 4.2±4.1 | 3.6±3.8 | 3.8±4.6 | 0.58 |
| Diabetes (%) | 48 (22.7) | 53 (25.1) | 77 (36.3) | 125 (59.2) | <0.001 |
| Elevated WC | 63 (29.6) | 70 (33.2) | 85 (40.1) | 115 (54.5) | <0.001 |
| High TG | 94 (44.1) | 104 (49.5) | 117 (55.2) | 142 (67.3) | <0.001 |
| Low HDL-C | 50 (23.6) | 46 (22.1) | 65 (30.8) | 75 (36.1) | 0.004 |
| Elevated BP | 127 (59.6) | 118 (55.9) | 147 (69.3) | 180 (85.3) | <0.001 |
| Impaired fasting Glu | 101 (47.4) | 107 (50.7) | 124 (58.5) | 155 (73.5) | <0.001 |
| Metabolic syndrome | 78 (36.8) | 88 (42.3) | 108 (51.2) | 144 (69.2) | <0.001 |
Continuous variables are presented by mean±SD and categorical variables are presented as the percentage of participants (%). p Values are according to the χ2 test for categorical variables and ANOVA for continuous variables.
ANOVA, analysis of variance; BMI, body mass index; BP, blood pressure; Glu, glucose; HDL-C, high-density lipoprotein cholesterol; HOMA-IR, homeostasis model assessment of insulin resistance; LDL-C, low-density lipoprotein cholesterol; TCHO, total cholesterol; TG, triglycerides; WC, waist circumference.