Table 1.
Baseline characteristics of type 2 diabetic patients by quartiles of serum 25(OH)D3 concentrations.
| Variables | Q1 (<8.9 ng/mL) |
Q2 (8.9–13.9 ng/mL) |
Q3 (13.9–18.1 ng/mL) |
Q4 (≥18.1 ng/mL) |
P value |
|---|---|---|---|---|---|
| n | 71 | 85 | 77 | 81 | — |
| Sex (M/F) | 40/31 | 51/34 | 50/27 | 55/26 | 0.462 |
| Age (years) | 53.0 ± 10.5 | 53.2 ± 12.4 | 52.4 ± 12.4 | 50.9 ± 12.4 | 0.614 |
| BMI (kg/m2) | 25.8 ± 3.7 | 25.3 ± 4.1 | 25.5 ± 2.9 | 25.0 ± 3.4 | 0.086 |
| SBP (mmHg) | 138.8 ± 20.2 | 136.8 ± 14.3 | 131.5 ± 17.5a | 133.5 ± 18.2 | 0.052 |
| DBP (mmHg) | 83.2 ± 11.4 | 85.5 ± 10.3 | 82.6 ± 8.6 | 83.0 ± 10.3 | 0.235 |
| Total cholesterol (mmol/L) | 4.5 ± 1.1 | 4.4 ± 1.1 | 4.2 ± 0.9 | 4.4 ± 1.0 | 0.300 |
| Triglyceride (mmol/L) | 2.2 ± 1.7 | 1.9 ± 1.8 | 1.9 ± 1.3 | 1.9 ± 1.4 | 0.485 |
| HDL-C (mmol/L) | 1.1 ± 0.3 | 1.2 ± 0.4a | 1.1 ± 0.2 | 1.1 ± 0.2 | 0.064 |
| LDL-C (mmol/L) | 3.0 ± 0.8 | 2.8 ± 0.9 | 2.6 ± 0.8a | 2.6 ± 0.8a | 0.028 |
| Uric acid (μmol/L) | 284.6 ± 91.1 | 266.5 ± 76.8 | 284.1 ± 92.7 | 275.3 ± 80.0 | 0.484 |
| Parathyroid hormone (pg/mL) | 47.8 ± 36.3 | 38.0 ± 15.0ab | 37.2 ± 12.4a | 31.3 ± 9.8a | 0.000 |
| Osteocalcin (ng/mL) | 13.4 ± 5.7 | 13.9 ± 5.1 | 12.8 ± 6.1 | 13.9 ± 5.3 | 0.665 |
| FBG (mmol/L) | 8.0 ± 3.4 | 7.9 ± 2.7 | 7.9 ± 2.8 | 8.7 ± 3.2 | 0.318 |
| HbA1c (%) | 10.2 ± 1.2 | 10.0 ± 1.3b | 9.6 ± 1.6ab | 8.6 ± 1.4a | 0.000 |
| Diabetes duration (months) | 112.5 ± 87.9 | 98.0 ± 86.6 | 84.8 ± 71.0a | 82.3 ± 75.4a | 0.085 |
| Calcium (mmol/L) | 2.22 ± 0.13 | 2.31 ± 0.10a | 2.32 ± 0.10a | 2.31 ± 0.10a | 0.000 |
| Carotid IMT (mm) | 1.23 ± 0.40 | 1.19 ± 0.31bc | 1.06 ± 0.22ab | 0.93 ± 0.17a | 0.000 |
| Carotid plaque [n (%)] | 40 (56.3%)b | 58 (68.2%)b | 48 (62.3%)b | 32 (39.5%) | 0.002 |
| Smoking history [n (%)] | 27 (38.0%) | 29 (34.1%) | 22 (28.6%) | 24 (29.6%) | 0.586 |
| Family history of DM [n (%)] | 37 (52.1%) | 39 (45.9%) | 30 (39.0%) | 44 (54.3%) | 0.217 |
| Hypertension history [n (%)] | 30 (42.3%) | 39 (45.9%) | 31 (40.3%) | 29 (35.8%) | 0.614 |
Data are presented as mean ± SD for continuous variables and number (percentages) for dichotomous variables. Differences were assessed by the LSD-t-test (for continuous variables) and by the chi-square test (for categorical variables). 1 mmHg = 0.133 kPa; SBP: systolic blood pressure; DBP: diastolic blood pressure; HDL-C: high-density lipoprotein cholesterol; LDL-C: low-density lipoprotein cholesterol; FBG: fasting blood glucose; HbA1c: glycosylated hemoglobin c; carotid IMT: carotid intima-media thickness; aanalysis of variance with LSD-t-test or chi-square test: P < 0.05 versus group Q1; banalysis of variance with LSD-t-test or chi-square test: P < 0.05 versus group Q4; canalysis of variance with LSD-t-test or chi-square test: P < 0.05 versus group Q3.