Table 1. Baseline Characteristics of the Derivation and Validation Cohortsa.
| Characteristic | Derivation cohort (n = 564 918) | Validation cohort (n = 190 484) |
|---|---|---|
| Demographic characteristics | ||
| Age, mean (SD), y | 65 (14) | 65 (13) |
| Weight, mean (SD), kg | 87 (22) | 88 (22) |
| Male sex | 369 455 (65) | 125 747 (66) |
| Race | ||
| White | 479 428 (85) | 161 567 (85) |
| Black | 65 726 (12) | 21 363 (11) |
| Medical history | ||
| History of diabetes | 190 280 (34) | 66 792 (35) |
| History of hypertension | 419 803 (74) | 142 620 (75) |
| History of dyslipidemia | 344 758 (61) | 116 511 (61) |
| Current or recent smoker | 191 638 (34) | 62 191 (33) |
| History of chronic lung disease | 67 370 (14) | 716 (11) |
| Current dialysis | 14 153 (3) | 4902 (3) |
| History of MI | 140 878 (25) | 47 419 (25) |
| History of HF | 70 925 (13) | 23 972 (13) |
| Prior PCI | 142 900 (25) | 50 279 (26) |
| Prior CABG | 76 462 (14) | 24 435 (13) |
| History of atrial fibrillation | 44 164 (8) | 18 148 (10) |
| Prior cerebrovascular disease | 68 891 (12) | 22 832 (12) |
| Prior peripheral arterial disease | 52 660 (9) | 15 167 (8) |
| Presentation | ||
| Presentation after cardiac arrest | 22 368 (4) | 7090 (4) |
| In cardiogenic shock | 22 095 (4) | 6688 (4) |
| In HF | 72 621 (13) | 22 619 (12) |
| Heart rate, mean (SD), beats/min | 84 (24) | 84 (24) |
| SBP at presentation, mean (SD), mm Hg | 146 (35) | 148 (36) |
| Presentation ECG findings | ||
| STEMI | 117 078 (39) | 73 136 (38) |
| New or presumed new | ||
| ST depressions | 219 648 (39) | 19 261 (10) |
| T-wave inversions | 64 294 (11) | 12 918 (7) |
| Transient ST-segment elevation lasting <20 min | 43 873 (8) | 1667 (1) |
| Initial laboratory values | ||
| Troponin ratio, mean (IQR) | 2.5 (0.50-16.3) | 3.5 (0.78-20.0) |
| Creatinine, mean (SD), mg/dL | 1.3 (1.2) | 1.3 (1.2) |
| Creatinine clearance, mean (SD), mL/min | 85 (43) | 85 (42) |
| Hemoglobin, mean (SD), g/dL | 14 (2) | 14 (2) |
Abbreviations: CABG, coronary artery bypass graft; ECG, electrocardiography; HF, heart failure; IQR, interquartile range; MI, myocardial infarction; PCI, percutaneous coronary intervention; SBP, systolic blood pressure; STEMI, ST-elevation myocardial infarction.
SI conversion factors: To convert creatinine to micromoles per liter, multiply by 88.4; to convert creatinine clearance to mL/s/m2, multiply by 0.0167; to convert hemoglobin to grams per liter, multiply by 10.
a
Data are presented as number (percentage) of patients unless otherwise indicated.