Table 1.
Baseline Characteristics of Overall Patients and Grouped Patients Stratified by Serum Calcium at Admission
| Serum Calcium, mmol/L | ||||||
|---|---|---|---|---|---|---|
| Characteristics | Overall | Q1, <2.12 | Q2, 2.12– < 2.21 | Q3, 2.21– < 2.28 | Q4, ≥2.28 | P Value |
| No. of patients, n | 2229 | 534 | 601 | 491 | 603 | |
| In‐hospital death | 56 (2.5) | 31 (5.8) | 12 (2.0) | 6 (1.2) | 7 (1.2) | <0.001 |
| Mean age, y | 64.55 ± 10.66 | 66.34 ± 10.11 | 65.16 ± 10.32 | 63.87 ± 10.78 | 62.92 ± 11.11 | <0.001 |
| Male sex | 1759 (78.9) | 438 (82.0) | 487 (81.0) | 377 (76.8) | 457 (75.8) | 0.022 |
| Serum calcium, mmol/L | 2.20 ± 0.15 | 2.02 ± 0.13 | 2.16 ± 0.025 | 2.23 ± 0.02 | 2.36 ± 0.15 | <0.001 |
| Calcium measuring time from admission, h | 2 (0.5–15) | 1.5 (0.5–13.5) | 2 (0.5–15) | 3 (0.5–15) | 2 (0.5–15) | 0.025 |
| Calcium measuring time of day | ||||||
| 6 am to 11 am | 1129 (50.6) | 267 (50.0) | 320 (53.2) | 251 (51.1) | 290 (48.1) | 0.344 |
| 12 pm to 5 pm | 388 (17.4) | 99 (18.5) | 90 (15.0) | 79 (16.1) | 120 (19.9) | 0.105 |
| 6 pm to 11 pm | 484 (21.7) | 108 (20.2) | 128 (21.3) | 115 (23.4) | 133 (22.1) | 0.650 |
| 00 am to 5 am | 229 (10.3) | 60 (11.2) | 63 (10.5) | 46 (9.4) | 60 (10.0) | 0.784 |
| GRACE risk score | 92.80 ± 26.27 | 98.23 ± 26.07 | 92.78 ± 25.97 | 89.49 ± 26.08 | 90.65 ± 26.20 | <0.001 |
| Previous or current smoker | 1307 (58.6) | 325 (60.9) | 365 (60.7) | 293 (59.7) | 324 (53.7) | <0.001 |
| HTN | 1217 (54.6) | 281 (52.6) | 308 (51.2) | 278 (56.6) | 350 (58.0) | 0.064 |
| DM | 554 (24.9) | 133 (24.9) | 135 (22.5) | 119 (24.2) | 167 (27.7) | 0.208 |
| Previous PCI or CABG | ||||||
| PCI | 162 (7.3) | 40 (7.5) | 47 (7.8) | 41 (8.4) | 34 (5.6) | 0.316 |
| CABG | 22 (1.0) | 5 (0.9) | 5 (0.8) | 4 (0.8) | 8 (1.3) | 0.796 |
| Previous drug treatment | ||||||
| Aspirin | 724 (32.5) | 139 (26.0) | 203 (33.8) | 175 (35.6) | 207 (34.3) | 0.003 |
| Statin | 460 (20.6) | 87 (16.3) | 124 (20.6) | 124 (25.3) | 125 (20.7) | 0.006 |
| ACEI/ARB | 420 (18.8) | 83 (15.5) | 119 (19.8) | 91 (18.5) | 127 (21.1) | 0.105 |
| β‐Blocker | 531 (23.8) | 92 (17.2) | 149 (24.8) | 132 (26.9) | 158 (26.2) | 0.001 |
| BMI, kg/m2 | 24.21 ± 2.94 | 24.06 ± 2.89 | 24.02 ± 2.75 | 24.27 ± 2.90 | 24.48 ± 3.17 | 0.028 |
| BP at admission, mm Hg | ||||||
| SBP | 130.27 ± 22.08 | 125.69 ± 23.82 | 129.46 ± 20.50 | 132.97 ± 21.64 | 132.93 ± 21.68 | <0.001 |
| DBP | 76.45 ± 12.84 | 73.90 ± 13.52 | 75.61 ± 11.98 | 77.55 ± 12.82 | 78.64 ± 12.64 | <0.001 |
| Heart rate at admission, bpm | 74.54 ± 14.38 | 76.21 ± 16.74 | 73.59 ± 13.39 | 73.44 ± 12.52 | 74.92 ± 14.39 | 0.005 |
| SCr, mmol/L | 90.79 ± 28.68 | 92.74 ± 33.71 | 89.00 ± 24.96 | 90.08 ± 26.76 | 91.43 ± 28.80 | 0.146 |
| Albumin, g/dL | 40.45 ± 4.25 | 37.75 ± 4.17 | 40.32 ± 3.51 | 41.48 ± 3.66 | 42.09 ± 4.25 | <0.001 |
| Lipids, mmol/L | ||||||
| TC | 4.14 ± 1.08 | 3.82 ± 0.96 | 4.08 ± 1.11 | 4.23 ± 0.99 | 4.39 ± 1.15 | <0.001 |
| LDL‐C | 2.45 ± 0.94 | 2.28 ± 0.81 | 2.37 ± 0.95 | 2.49 ± 0.87 | 2.62 ± 1.04 | <0.001 |
| HDL‐C | 1.15 ± 0.37 | 1.12 ± 0.46 | 1.13 ± 0.37 | 1.17 ± 0.34 | 1.16 ± 0.30 | 0.077 |
| TG | 1.79 ± 1.17 | 1.50 ± 0.81 | 1.75 ± 1.25 | 1.78 ± 1.16 | 2.07 ± 1.28 | <0.001 |
| WBC count, ×109/L | 7.87 ± 3.42 | 8.49 ± 3.88 | 7.70 ± 3.47 | 7.48 ± 3.13 | 7.83 ± 3.10 | <0.001 |
| Hgb, g/L | 133.87 ± 18.09 | 126.70 ± 19.21 | 133.56 ± 17.36 | 136.43 ± 16.20 | 138.48 ± 17.24 | <0.001 |
| Platelet count, ×109/L | 162.88 ± 61.52 | 162.00 ± 63.39 | 158.19 ± 61.83 | 165.74 ± 65.09 | 166.01 ± 56.16 | 0.101 |
| Serum potassium, mmol/L | 3.94 ± 0.47 | 3.94 ± 0.53 | 3.93 ± 0.43 | 3.98 ± 0.44 | 3.99 ± 0.45 | <0.001 |
| Serum sodium, mmol/L | 140.81 ± 3.73 | 139.91 ± 4.70 | 140.94 ± 3.34 | 141.17 ± 3.67 | 141.18 ± 2.98 | <0.001 |
| Serum chloride, mmol/L | 104.73 ± 5.74 | 105.07 ± 7.32 | 105.30 ± 3.31 | 104.71 ± 4.84 | 103.87 ± 6.59 | <0.001 |
| Lesion characteristic | ||||||
| LM disease | 221 (9.9) | 54 (10.1) | 63 (10.5) | 46 (9.4) | 58 (9.6) | 0.927 |
| 3‐vessel disease | 529 (23.7) | 119 (22.3) | 136 (22.6) | 132 (26.9) | 142 (23.5) | 0.292 |
| PCI | 1741 (78.1) | 420 (78.7) | 472 (78.5) | 380 (77.4) | 469 (77.8) | 0.952 |
| Clinical diagnosis | ||||||
| STEMI | 471 (21.1) | 137 (25.7) | 116 (19.3) | 92 (18.7) | 127 (21.0) | 0.023 |
| NSTEMI | 230 (10.3) | 61 (11.4) | 62 (10.3) | 40 (8.1) | 67 (11.1) | 0.304 |
| UA | 1528 (68.6) | 336 (62.9) | 434 (72.1) | 370 (75.2) | 411 (67.9) | <0.001 |
| Drug treatment in hospital | ||||||
| ASA | 2151 (96.5) | 510 (95.5) | 585 (97.3) | 472 (96.1) | 584 (96.8) | 0.358 |
| Clopidogrel | 2137 (95.9) | 507 (94.9) | 576 (95.8) | 472 (96.1) | 582 (96.5) | 0.597 |
| Statin | 2089 (93.7) | 502 (94.2) | 559 (93.0) | 463 (94.3) | 565 (93.7) | 0.805 |
| ACEI/ARB | 1318 (59.1) | 297 (55.6) | 351 (58.5) | 292 (59.5) | 378 (62.7) | 0.111 |
| β‐Blocker | 1523 (68.3) | 325 (60.9) | 398 (66.3) | 345 (70.3) | 455 (75.5) | <0.001 |
| Nitrated derivative | 1025 (46.0) | 212 (39.7) | 290 (48.3) | 237 (48.3) | 286 (47.4) | 0.10 |
Abbreviations: ACEI, angiotensin‐converting enzyme inhibitor; ARB, angiotensin‐receptor blocker; ASA, aspirin; BP, blood pressure; CABG, coronary artery bypass grafting; DBP, diastolic blood pressure; DM, diabetes mellitus; HDL‐C, high‐density lipoprotein cholesterol; Hgb, hemoglobin; HTN, hypertension; IQR, interquartile range; LDL‐C, low‐density lipoprotein cholesterol; LM, left main; PCI, percutaneous coronary intervention; Q, quartile; SBP, systolic blood pressure; SCr, serum creatinine; SD, standard deviation; STEMI, ST‐segment elevation myocardial infarction; TC, total cholesterol; TG, triglycerides; UA, unstable angina; WBC, white blood cell.
Data are expressed as n (%), mean ± SD, or median (IQR), as appropriate.