Table 1. General characteristics of the subjects according to 25(OH)D quartiles.
| Variable | 25(OH)D (ng/mL) | p value | ||||
|---|---|---|---|---|---|---|
| Q1(≤12.40) | Q2(12.50 to15.10) | Q3(15.20 to19.00) | Q4(≥19.10) | Total | ||
| N (%) | 295(25.1) | 288(24.5) | 296(25.2) | 296(25.2) | 1175(100.0) | - |
| Male (%) | 72(24.4) | 102(35.4) | 166(56.1) | 223(75.3) | 563(47.9) | <0.001 |
| Age (years) | 68.0±8.0 | 67.8±6.9 | 67.2±7.4 | 67.1±7.5 | 67.5±7.5 | 0.350 |
| Diabetic duration (years) | 9.8±8.5 | 8.9±7.8 | 9.7±8.7 | 10.2±9.2 | 9.6±8.6 | 0.328 |
| Month of blood collection | <0.001 | |||||
| April | 91(30.8) | 69(24.0) | 54(18.2) | 36(12.2) | 250(21.3) | |
| May | 117(39.7) | 102(35.4) | 93(31.4) | 80(27.0) | 392(33.4) | |
| June | 68(23.1) | 79(27.4) | 97(32.8) | 114(38.5) | 358(30.5) | |
| July | 19(6.4) | 38(13.2) | 52(17.6) | 66(22.3) | 175(14.9) | |
| Height (cm) | 155.9±7.7 | 157.0±8.4 | 160.3±8.6 | 163.1±8.0 | 159.1±8.7 | <0.001 |
| Weight (kg) | 60.3±9.0 | 62.0±9.9 | 64.1±10.1 | 65.6±8.6 | 63.0±9.6 | <0.001 |
| BMI (kg/m2) | 24.8±3.2 | 25.1±3.1 | 24.9±3.1 | 24.6±2.4 | 24.9±3.0 | 0.241 |
| Current smoker (%) | 22(7.5) | 32(11.1) | 48(16.2) | 48(16.3) | 150(12.8) | <0.001 |
| aPhysically active (%) | 37(13.5) | 42(15.0) | 65(22.3) | 82(28.2) | 226(19.9) | <0.001 |
| Hypertensive medication (%) | 174(59.0) | 167(58.0) | 178(60.1) | 163(55.1) | 682(58.0) | 0.633 |
| Total cholesterol (mg/dL) | 204.6±49.3 | 194.8±40.0 | 181.5±41.2 | 175.9±37.5 | 189.1±43.6 | <0.001 |
| Triglycerides (mg/dL) | 185.6±219.1 | 166.4±121.3 | 146.1±88.4 | 147.7±92.6 | 161.4±141.4 | 0.002 |
| LDL cholesterol (mg/dL) | 120.6±40.9 | 115.1±35.6 | 104.8±37.2 | 100.4±33.9 | 110.1±37.8 | <0.001 |
| HDL cholesterol (mg/dL) | 50.6±11.3 | 48.9±12.6 | 48.7±11.5 | 46.4±10.2 | 48.6±11.5 | <0.001 |
| Fasting glucose (mg/dL) | 145.7±43.5 | 144.4±44.4 | 142.7±39.0 | 142.2±37.8 | 143.7±41.2 | 0.725 |
| Hemoglobin A1c (%) | 7.5±1.5 | 7.2±1.3 | 7.1±1.3 | 7.2±1.3 | 7.3±1.4 | 0.004 |
| PTH (pg/mL) | 46.2±36.9 | 41.2±19.3 | 37.2±21.3 | 33.5±13.4 | 39.5±24.7 | <0.001 |
All values are given as n (%) or mean ± standard deviation.
BMI, body mass index; 25(OH)D, 25-hydroxyvitamin D; LDL, low-density lipoprotein; HDL, high-density lipoprotein; PTH, parathyroid hormone
aSubjects who performed 30 min or more of moderate activity at least 5 days a week or 20 min of vigorous physical activity at least 3 days a week were regarded as doing physical activity