Table 1. Baseline Characteristics of Study Subjects.
| Variable | Metabolic syndrome | Overall (n=13,496) | ||
|---|---|---|---|---|
| No (n=11,832) | Yes (n=1,664) | P value | ||
| Male sex | 6,852 (58) | 1,316 (79) | <0.001 | 8,168 (61) |
| Age, yr | 50.5±6.6 | 52.3±6.5 | <0.001 | 50.7±6.6 |
| Smoking, current/former/never, % | 17/29/54 | 27/37/36 | <0.001 | 19/30/51 |
| BMI, kg/m2 | 23.4±2.6 | 26.5±2.4 | <0.001 | 23.8±2.7 |
| Overweight (25≤BMI<30) | 2,784 (24) | 1,258 (76) | <0.001 | 4,042 (30) |
| Obesity (BMI≥30) | 134 (1) | 109 (7) | <0.001 | 243 (2) |
| Body fat, % | 23.3±6.1 | 25.7±5.7 | 0.004 | 23.6±6.1 |
| Male | 20.2±4.4 | 23.8±4.1 | <0.001 | 20.8±4.5 |
| Female | 27.7±5.4 | 33.1±4.9 | <0.001 | 28.0±5.5 |
| Abdominal fat, % | 0.88±0.06 | 0.93±0.06 | <0.001 | 0.88±0.06 |
| Male | 0.89±0.06 | 0.93±0.05 | <0.001 | 0.90±0.06 |
| Female | 0.85±0.06 | 0.91±0.06 | <0.001 | 0.86±0.06 |
| Systolic BP, mm Hg | 109.9±14.2 | 121.0±15.3 | <0.001 | 111.3±14.8 |
| Diastolic BP, mm Hg | 67.7±9.8 | 74.4±10.0 | <0.001 | 68.5±10.0 |
| Total cholesterol, mg/dL | 188.0±30.7 | 191.9±33.2 | <0.001 | 188.5±31.0 |
| LDL-C, mg/dL | 122.8±27.9 | 125.4±29.9 | 0.001 | 123.1±28.2 |
| HDL-C, mg/dL | 59.4±13.5 | 47.3±10.9 | <0.001 | 57.9±13.8 |
| Male | 55.5±11.9 | 47.2±11.3 | <0.001 | 54.2±12.2 |
| Female | 64.8±13.8 | 47.7±9.2 | <0.001 | 63.6±14.2 |
| Triglycerides, mg/dL | 114.7±63.9 | 214.0±102.5 | <0.001 | 126.9±77.1 |
| Fasting glucose, mg/dL | 87.5±12.9 | 103.7±23.8 | <0.001 | 89.5±15.6 |
| HbA1c, % | 5.3±0.5 | 5.9±0.9 | <0.001 | 5.4±0.6 |
| HOMA-IR | 1.9±0.9 | 2.9±1.5 | <0.001 | 2.1±1.1 |
| TSH, mU/L | 2.4±1.3 | 2.3±1.3 | 0.017 | 2.3±1.3 |
| T3, nmol/L | 1.72±0.28 | 1.78±0.29 | <0.001 | 1.72±0.28 |
| T4, nmol/L | 108.6±17.9 | 108.3±18.4 | 0.521 | 108.6±17.9 |
| T3-to-T4 ratio | 0.016±0.003 | 0.017±0.003 | <0.001 | 0.016±0.003 |
Values are expressed as number (%) or mean±SD. Demographic and biochemical characteristics of the study population with respect to the development of metabolic syndrome were compared using an independent t test for continuous variables and chi-square test for categorical variables.
BMI, body mass index; BP, blood pressure; LDL-C, low density lipoprotein cholesterol; HDL-C, high density lipoprotein cholesterol; HbA1c, glycated hemoglobin; HOMA-IR, homeostasis model assessment of insulin resistance; TSH, thyroid stimulating hormone; T3, triiodothyronine; T4, thyroxine.