Table 1.
Baseline patient characteristics.
| All (n = 60) | CAC < 1,000 (n = 33) | CAC ≥ 1,000 (n = 27) | P | |
|---|---|---|---|---|
| Age (years) | 63.1 ± 11.9 | 61.8 ± 13.1 | 64.7 ± 10.4 | 0.335* |
| Male | 41 (68.3%) | 19 (57.6%) | 22 (81.5%) | 0.057† |
| Hemodialysis duration (months) | 87.6 (44.1, 152.2) | 87.4 (42.1, 138.8) | 96.9 (47.5, 165.2) | 0.637‡ |
| Cardiovascular disease | 10 (16.7%) | 0 (0%) | 10 (37%) | < 0.001† |
| Diabetes mellitus | 21 (35%) | 12 (36.4%) | 9 (33.3%) | 1.000† |
| Body mass index (kg/m2) | 21.5 (20.6, 23.2) | 21.4 (20.4, 22.9) | 21.5 (20.9, 23.5) | 0.440‡ |
| Ankle-brachial index | 1.2 (1.1, 1.2) | 1.2 (1.1, 1.2) | 1.2 (1.1, 1.2) | 0.789‡ |
| Albumin-adjusted calcium (mg/dL) | 9.0 ± 0.5 | 9.0 ± 0.5 | 9.0 ± 0.4 | 0.940* |
| Serum phosphate (mg/dL) | 5.2 (4.6, 5.7) | 4.9 (4.5, 5.2) | 5.5 (4.7, 6.1) | 0.020‡ |
| Intact parathyroid hormone (pg/mL) | 176.2 (152.1, 245.4) | 171.8 (152.2, 211.7) | 188.4 (156.3, 255.8) | 0.352‡ |
| Alkaline phosphatase (U/mL) | 259.1 (205.5, 318.8) | 264.3 (212.5, 346.0) | 251.2 (197.4, 282.7) | 0.178‡ |
| Magnesium (mg/dL) | 2.6 ± 0.3 | 2.6 ± 0.3 | 2.5 ± 0.3 | 0.174* |
| Triglyceride (mg/dL) | 107.3 (70.6, 148.9) | 94.3 (58.5, 144.8) | 111.3 (96.7, 154.4) | 0.099‡ |
| LDL cholesterol (mg/dL) | 86.2 ± 21.6 | 81.0 ± 21.0 | 92.7 ± 21.5 | 0.038* |
| HDL cholesterol (mg/dL) | 40.7 (32.8, 52.6) | 44.2 (34.9, 54.6) | 36.8 (29.7, 51.0) | 0.115‡ |
| Uric acid (mg/dL) | 7.1 ± 0.9 | 7.1 ± 0.8 | 7.2 ± 1.0 | 0.548* |
| Beta-2 microglobulin (µg/L) | 27.1 (23.0, 29.2) | 27.3 (21.2, 29.2) | 27.0 (23.3, 29.1) | 0.876‡ |
| Blood urea nitrogen (mg/dL) | 60.1 ± 10.2 | 59.0 ± 8.6 | 61.4 ± 11.9 | 0.397* |
| Hemoglobin (g/dL) | 10.7 (10.3, 11.0) | 10.9 (10.5, 11.1) | 10.4 (10.0, 10.9) | 0.023‡ |
| Serum albumin (g/dL) | 3.7 (3.6, 4.0) | 3.7 (3.6, 4.0) | 3.7 (3.6, 4.0) | 0.994‡ |
| Calcium carbonate intake | 49 (81.7%) | 27 (81.8%) | 22 (81.5%) | 1.000† |
| Vitamin D medication | 26 (43.3%) | 11 (33.3%) | 15 (55.6%) | 0.117† |
| Statin intake | 10 (16.7%) | 5 (15.2%) | 5 (18.5%) | 0.742† |
| SOx (μg/L) | 266.9 (229.5, 318.5) | 256.1 (228.2, 290.1) | 280.4 (251.3, 355.5) | 0.081‡ |
| Major artery calcification volume (cm3) | 7.0 (3.0, 18.4) | 3.6 (1.6, 8.6) | 12.2 (6.1, 31.3) | < 0.001‡ |
Continuous variables are reported as mean ± standard deviation for normally distributed data or median (inter-quartile range) for non-normally distributed data. Discrete variables are expressed as numeral (percentage). The subjects were divided into two groups according to CAC score, and statistical significance was tested by using Welch’s t-test for normally distributed data, the Wilcoxon rank sum test for non-normally distributed data, and Fisher’s exact test for discrete variables. A two-tailed P value of < 0.05 was considered to indicate statistical significance.
CAC coronary artery calcification, HDL high-density lipoprotein, LDL low-density lipoprotein, SOx serum oxalate concentration.
*Welch’s t-test; †Fisher’s exact test; ‡the Wilcoxon rank sum test.