Table 1.
Demographic and clinical characteristics of risk groups.
| Low-risk category (n = 1,128) | Intermediate-risk category (n = 1,253) | High-risk category (n = 312) | P Value | |
|---|---|---|---|---|
| Age, years | 60 (53–68) | 62 (53–69) | 63 (54–72) | <0.001 |
| Male | 883 (78.3%) | 941 (75.1%) | 217 (69.6%) | 0.005 |
| Body mass index, kg/m2 | 24.16 (22.39–26.05) | 24.11 (21.97–25.87) | 24.02 (22.03–25.69) | 0.170 |
| Medical history | ||||
| Smoker (former or current) | 583 (51.7%) | 633 (50.5%) | 142 (45.5%) | 0.155 |
| Hypertension | 525 (46.5%) | 602 (48.0%) | 151 (48.4%) | 0.718 |
| Diabetes mellitus | 202 (17.8%) | 260 (20.8%) | 98 (31.4%) | <0.001 |
| Dyslipidemia | 809 (71.7%) | 883 (70.5%) | 214 (68.6%) | 0.532 |
| Previous MI | 122 (10.8%) | 134 (10.7%) | 35 (11.2%) | 0.965 |
| Previous PCI | 47 (4.2%) | 50 (4.0%) | 8 (2.6%) | 0.422 |
| Previous stroke | 46 (4.1%) | 65 (5.2%) | 22 (7.1%) | 0.086 |
| Presentation characteristics | ||||
| Heart rate, beats/min | 76 (68–78) | 76 (69–83) | 76 (69–88) | <0.001 |
| SBP, mm Hg | 124 (118–135) | 123 (111–138) | 120 (105–131) | <0.001 |
| Killip class I | 960 (85.1%) | 970 (77.4%) | 227 (72.8%) | <0.001 |
| Killip class II | 122 (10.8%) | 172 (13.7%) | 41 (13.1%) | |
| Killip class III | 42 (3.7%) | 93 (7.4%) | 27 (8.7%) | |
| Killip class IV | 4 (0.4%) | 18 (1.4%) | 17 (5.4%) | |
| Cardiac arrest | 6 (0.5%) | 16 (1.3%) | 7 (2.2%) | 0.022 |
| Laboratory findings | ||||
| WBC count, ×109/L | 5.98 (5.23–6.98) | 8.89 (7.21–10.07) | 9.10 (8.80–10.77) | <0.001 |
| Neutrophil count, ×109/L | 3.79 (3.12–4.53) | 6.54 (4.24–8.01) | 6.67 (5.64–8.53) | <0.001 |
| Lymphocyte count, ×109/L | 1.63 (1.26–2.04) | 1.58 (1.18–2.07) | 1.63 (1.22–2.16) | 0.351 |
| Monocyte count, ×109/L | 0.37 (0.28–0.47) | 0.49 (0.35–0.71) | 0.59 (0.38–0.82) | <0.001 |
| Eosinophil count, ×109/L | 0.08 (0.05–0.15) | 0.05 (0.01–0.11) | 0.04 (0.01–0.10) | <0.001 |
| Basophil count, ×109/L | 0.02 (0.01–0.03) | 0.02 (0.01–0.02) | 0.01 (0.01–0.02) | 0.001 |
| RBC count, ×1012/L | 4.81 (4.53–5.12) | 4.69 (4.26–5.14) | 4.42 (3.97–4.94) | <0.001 |
| Hemoglobin, g/L | 152 (143–161) | 148 (131–160) | 138 (121–156) | <0.001 |
| RDW, % | 13.20 (12.80–13.80) | 13.50 (12.90–14.00) | 13.70 (13.13–14.40) | <0.001 |
| MCV, fL | 92.80 (89.90–96.10) | 91.70 (88.60–95.00) | 92.10 (88.43–95.60) | <0.001 |
| MCH, pg | 31.60 (30.50–32.70) | 31.30 (30.10–32.40) | 31.20 (29.80–32.20) | <0.001 |
| MCHC, g/L | 339 (333–346) | 341 (332–349) | 337 (328–345) | <0.001 |
| Hematocrit, % | 44.80 (42.20–47.40) | 43.20 (39.40–46.40) | 41.85 (36.53–46.10) | <0.001 |
| Platelet count, ×109/L | 168 (131–206) | 188 (147–231) | 163 (130–210) | <0.001 |
| MPV, fL | 11.50 (10.70–12.40) | 11.30 (10.50–12.10) | 13.30 (12.03–13.80) | <0.001 |
| PDW, fL | 14.90 (13.00–16.70) | 14.60 (12.80–15.90) | 18.30 (14.98–20.40) | <0.001 |
| P-LCR, % | 38.20 (32.33–44.40) | 37.00 (30.10–42.00) | 50.55 (39.39–54.20) | <0.001 |
| Plateletcrit, % | 0.210 (0.170–0.230) | 0.220 (0.180–0.260) | 0.219 (0.180–0.260) | <0.001 |
| LDL, mmol/L | 2.40 (1.88–2.98) | 2.58 (1.99–3.24) | 2.63 (2.09–3.16) | <0.001 |
| Glucose, mmol/L | 5.60 (4.89–7.18) | 6.20 (5.12–7.98) | 6.86 (5.44–9.81) | <0.001 |
| Creatinine, µmol/L | 75.75 (67.00–84.00) | 74.50 (64.00–87.05) | 77.40 (64.00–96.90) | 0.071 |
| Elevated cardiac enzymes | 521 (46.2%) | 898 (71.7%) | 236 (75.6%) | <0.001 |
| ST-segment deviation on ECG | 450 (39.9%) | 810 (64.6%) | 209 (67.0%) | <0.001 |
| LVEF, % | 56 (55–60) | 56 (49–58) | 55 (47–59) | <0.001 |
| GRACE risk score | 118 (87–166) | 162 (114–189) | 172 (132–203) | <0.001 |
| ACS presentation | <0.001 | |||
| NSTE-ACS | 724 (64.2%) | 513 (40.9%) | 125 (40.1%) | |
| STEMI | 404 (35.8%) | 740 (59.1%) | 187 (59.9%) | |
| Medical treatment | ||||
| Aspirin | 1,101 (97.6%) | 1,213 (96.8%) | 308 (98.7%) | 0.136 |
| P2Y12 inhibitor | 1,068 (94.7%) | 1,197 (95.5%) | 299 (95.8%) | 0.538 |
| Statin | 1,003 (88.9%) | 1,135 (90.6%) | 275 (88.1%) | 0.276 |
| ACEI⁄ARB | 761 (67.5%) | 796 (63.5%) | 201 (64.4%) | 0.124 |
| β-Blocker | 636 (56.4%) | 692 (55.2%) | 168 (53.8%) | 0.692 |
Abbreviation: MI, myocardial infarction; PCI, percutaneous coronary intervention; SBP, systolic blood pressure; WBC, white blood cell; RBC, red blood cell; RDW, red blood cell distribution width; MCV, mean corpuscular volume; MCH, mean corpuscular hemoglobin; MCHC, mean corpuscular hemoglobin concentration; MPV, mean platelet volume; PDW, platelet distribution width; P-LCR, platelet large cell ratio; LDL, low-density lipoprotein cholesterol; ECG, electrocardiograms; LVEF, left ventricular ejection fraction; GRACE, Global Registry of Acute Coronary Events; ACS, acute coronary syndrome; NSTE-ACS, non-ST-segment elevation ACS; STEMI, ST-segment elevation MI; ACEI, angiotensin-converting enzyme inhibitor; and ARB, angiotensin-receptor blocker.
Values are expressed as number (percentage) or median (interquartile range).
Low-risk category is defined as patients with WBC count <8.62 × 109/L and a hemoglobin level ≥133 g/L.
Intermediate-risk category is defined as patients with either WBC count (<8.62 × 109/L) + hemoglobin level (<133 g/L) or WBC count (≥8.62 × 109/L) + MPV level (<12.90 fL) + hemoglobin level (≥128 g/L).
High-risk category is defined as patients with either WBC count (≥8.62 × 109/L) + MPV level (≥12.90 fL) or WBC count (≥8.62 × 109/L) + MPV level (<12.90 fL) + hemoglobin level (<128 g/L).