Table 1.
Baseline Characteristics of Patients Stratified by High-Sensitivity Cardiac Troponin Concentration
| All (n = 918) | Group 1 (n = 316) | Group 2 (n = 236) | Group 3 (n = 252) | Group 4 (n = 114) | P-value | |
|---|---|---|---|---|---|---|
| Range of troponin concentration, ng/L | ||||||
| Males | ≤3 | 3 to 6 | 6 to 34 | >34 | ||
| Females | ≤1 | 2 to 4 | 4 to 16 | >16 | ||
| Male sex | 426 (46.4) | 156 (49.4) | 101 (42.8) | 127 (50.4) | 42 (36.8) | 0.043 |
| Age (years) | 53.0 ± 23.0 | 34.0 ± 13.1 | 50.5 ± 17.9 | 67.9 ± 18.2 | 77.6 ± 16.5 | <0.001 |
| Chest pain | 75 (8.3) | 24 (7.7) | 18 (7.7) | 21 (8.4) | 12 (10.7) | 0.776 |
| Risk factors | ||||||
| Smoker | 258 (33.2) | 102 (37.6) | 73 (36.5) | 58 (27.0) | 25 (27.8) | 0.04 |
| Ex-smoker | 119 (15.3) | 11 (4.1) | 21 (10.5) | 61 (28.2) | 26 (28.9) | <0.001 |
| Hypertension | 257 (28.4) | 16 (5.2) | 54 (23.1) | 116 (46.6) | 71 (62.8) | <0.001 |
| Hyperlipidemia | 230 (25.4) | 16 (5.2) | 49 (20.9) | 109 (43.8) | 56 (49.1) | <0.001 |
| Family history | 9 (1.0) | 1 (0.3) | 3 (1.3) | 3 (1.2) | 2 (1.8) | 0.491 |
| Past medical history | ||||||
| Ischemic heart disease | 127 (14.0) | 9 (2.9) | 18 (7.7) | 62 (24.9) | 38 (33.3) | <0.001 |
| Myocardial infarction | 61 (6.7) | 5 (1.6) | 7 (3.0) | 31 (12.4) | 18 (15.8) | <0.001 |
| Cerebrovascular disease | 83 (9.2) | 3 (1.0) | 17 (7.3) | 37 (14.9) | 26 (22.8) | <0.001 |
| Peripheral vascular disease | 43 (4.7) | 4 (1.3) | 5 (2.1) | 19 (7.6) | 15 (13.2) | <0.001 |
| Diabetes | 81 (8.9) | 13 (4.2) | 18 (7.7) | 35 (13.9) | 15 (13.2) | <0.001 |
| Previous revascularization | ||||||
| PCI | 28 (3.1) | 4 (1.3) | 5 (2.1) | 13 (5.2) | 6 (5.3) | 0.022 |
| CABG | 19 (2.1) | 0 (0.0) | 1 (0.4) | 9 (3.6) | 9 (7.9) | <0.001 |
| Admission physiological parameters | ||||||
| Medium or high risk NEWS (≥5) | 34 (5.7) | 5 (2.4) | 4 (2.7) | 9 (5.5) | 16 (19.5) | <0.001 |
| Respiratory rate (bpm) | 18.3 ± 4.3 | 17.6 ± 3.7 | 17.3 ± 3.0 | 18.5 ± 3.8 | 21.4 ± 6.5 | <0.001 |
| Temperature (°C) | 36.9 ± 0.9 | 36.8 ± 0.8 | 36.8 ± 0.8 | 37.0 ± 0.9 | 37.1 ± 1.2 | 0.013 |
| Pulse rate (bpm) | 87.7 ± 22.1 | 85.8 ± 19.0 | 86.1 ± 20.4 | 87.6 ± 22.7 | 95.9 ± 28.8 | 0.001 |
| Systolic BP (mm Hg) | 130.5 ± 22.3 | 127.0 ± 16.7 | 130.4 ± 21.8 | 134.9 ± 25.5 | 130.1 ± 26.8 | 0.003 |
| Oxygen saturations (%) | 96.8 ± 3.0 | 97.9 ± 1.8 | 97.1 ± 2.1 | 96.0 ± 3.3 | 95.1 ± 4.7 | <0.001 |
| On oxygen | 52 (6.3) | 4 (1.5) | 6 (2.8) | 19 (8.3) | 23 (21.9) | <0.001 |
| Consciousness | 0.01 | |||||
| Alert | 880 (96.6) | 306 (98.1) | 227 (97.0) | 243 (96.8) | 104 (91.2) | |
| Verbal | 14 (1.5) | 3 (1.0) | 5 (2.1) | 1 (0.4) | 5 (4.4) | |
| Pain | 7 (0.8) | 2 (0.6) | 0 (0.0) | 4 (1.6) | 1 (0.9) | |
| Unresponsive | 10 (1.1) | 1 (0.3) | 2 (0.9) | 3 (1.2) | 4 (3.5) | |
| Killip class | <0.001 | |||||
| 0 | 6 (0.7) | 1 (0.3) | 0 (0.0) | 2 (0.8) | 3 (2.7) | |
| 1 | 819 (90.8) | 304 (99.0) | 222 (95.7) | 212 (84.8) | 81 (71.7) | |
| 2 | 65 (7.2) | 2 (0.7) | 9 (3.9) | 30 (12.0) | 24 (21.2) | |
| 3 | 11 (1.2) | 0 (0.0) | 1 (0.4) | 6 (2.4) | 4 (3.5) | |
| 4 | 1 (0.1) | 0 (0.0) | 0 (0.0) | 0 (0.0) | 1 (0.9) | |
| Hematology and biochemistry | ||||||
| Hemoglobin (g/dL) | 13.3 ± 2.0 | 13.9 ± 1.5 | 13.5 ± 1.7 | 12.9 ± 2.1 | 12.1 ± 2.4 | <0.001 |
| Creatinine (mg/dL) | 0.96 ± 0.74 | 0.80 ± 0.16 | 0.88 ± 0.78 | 1.07 ± 0.90 | 1.30 ± 1.00 | <0.001 |
| Urea (mg/dL) | 5.9 ± 3.7 | 4.4 ± 1.5 | 5.1 ± 2.4 | 7.0 ± 4.1 | 9.7 ± 5.5 | <0.001 |
| Admission drugs | ||||||
| Aspirin | 130 (14.5) | 7 (2.3) | 19 (8.2) | 66 (27.0) | 38 (33.9) | <0.001 |
| Clopidogrel | 62 (6.9) | 5 (1.6) | 10 (4.3) | 33 (13.5) | 14 (12.5) | <0.001 |
| Beta-blockers | 109 (12.1) | 9 (2.9) | 24 (10.3) | 45 (18.4) | 31 (27.7) | <0.001 |
| ACE-I/ARB | 143 (15.9) | 9 (2.9) | 34 (14.7) | 63 (25.8) | 37 (33.0) | <0.001 |
| Statin | 192 (21.4) | 13 (4.2) | 43 (18.5) | 91 (37.3) | 45 (40.2) | <0.001 |
| Warfarin | 35 (3.9) | 1 (0.3) | 7 (3.0) | 16 (6.6) | 11 (9.9) | <0.001 |
| PPI | 184 (20.5) | 28 (9.0) | 52 (22.4) | 65 (26.6) | 39 (34.8) | <0.001 |
| Admission ECG | ||||||
| ST elevation | 5 (1.0) | 1 (0.6) | 2 (1.7) | 0 (0.0) | 2 (2.3) | 0.261 |
| ST depression | 9 (1.7) | 0 (0.0) | 1 (0.8) | 2 (1.2) | 6 (6.9) | 0.001 |
| T-wave inversion | 34 (6.5) | 3 (2.0) | 6 (5.0) | 16 (10.0) | 9 (10.3) | 0.012 |
| New LBBB | 5 (1.0) | 0 (0.0) | 0 (0.0) | 1 (0.6) | 4 (4.6) | 0.002 |
| Old LBBB | 13 (2.5) | 0 (0.0) | 0 (0.0) | 8 (5.0) | 5 (5.7) | 0.002 |
| RBBB | 15 (2.9) | 2 (1.3) | 1 (0.8) | 7 (4.4) | 5 (5.7) | 0.073 |
| Outcomes | ||||||
| Admitted to hospital | 512 (56.2) | 128 (41.0) | 119 (50.6) | 169 (67.6) | 96 (84.2) | <0.001 |
| 30-day death | 32 (3.5) | 2 (0.6) | 1 (0.4) | 7 (2.8) | 22 (19.3) | <0.001 |
| 1-year death | 102 (11.1) | 6 (1.9) | 13 (5.5) | 40 (15.9) | 43 (37.7) | <0.001 |
Values are n (%) or mean ± SD.
ACE-I/ARB = angiotensin converting enzyme inhibitor/angiotensin receptor blocker; BP = blood pressure; bpm = breaths/beats per minute; CABG = coronary artery bypass grafting; ECG = electrocardiogram; LBBB = left bundle branch block; NEWS = National Early Warning Score; PCI = percutaneous coronary intervention; PPI = proton pump inhibitor; RBBB = right bundle branch block.