Table 1.
Baseline characteristics of all patients with suspected acute coronary syndrome stratified by peak troponin concentration. Figures are numbers (percentage) of patients unless stated otherwise
| Peak troponin concentration (µg/L) | P value* | Post hoc analysis P values | ||||||
|---|---|---|---|---|---|---|---|---|
| All (n=2092) | <0.012 (n=988) | 0.012-0.049 (n=352) | ≥0.050 (n=752) | <0.012 v 0.012-0.049 | <0.012 v ≥0.050 | 0.012-0.049 v ≥0.050 | ||
| Mean (SD) age (years) | 65 (15) | 60 (14) | 70 (14) | 68 (14) | <0.001 | <0.001 | <0.001 | >0.05 |
| Men | 1192 (57) | 524 (53) | 207 (59) | 461 (61) | 0.002 | 0.071 | <0.001 | 0.429 |
| Medical history: | ||||||||
| Previous IHD | 1161 (55) | 499 (51) | 264 (75) | 398 (55) | <0.001 | <0.001 | 0.333 | <0.001 |
| Previous revascularisation | 460 (22) | 202 (20) | 100 (28) | 158 (19) | 0.006 | 0.003 | 0.811 | 0.008 |
| Previous stroke | 160 (8) | 59 (6) | 35 (10) | 66 (9) | 0.019 | 0.015 | 0.031 | 0.576 |
| Peripheral vascular disease | 117 (6) | 46 (5) | 17 (5) | 54 (7) | 0.060 | — | — | — |
| Risk factors: | ||||||||
| Current smoker | 611 (29) | 299 (30) | 67 (19) | 245 (33) | <0.001 | <0.001 | 0.321 | <0.001 |
| Ex-smoker | 430 (21) | 195 (20) | 91 (26) | 145 (19) | 0.028 | 0.019 | 0.855 | 0.015 |
| Non-smoker | 1051 (50) | 494 (50) | 194 (55) | 362 (48) | 0.096 | — | — | — |
| Hypertension | 791 (38) | 326 (33) | 157 (45) | 308 (42) | <0.001 | <0.001 | <0.001 | 0.267 |
| Hyperlipidaemia | 1020 (49) | 445 (45) | 218 (62) | 357 (47) | <0.001 | <0.001 | 0.332 | <0.001 |
| Family history | 405 (19) | 224 (23) | 39 (11) | 142 (19) | <0.001 | <0.001 | 0.058 | <0.001 |
| Diabetes mellitus | 346 (17) | 137 (14) | 63 (18) | 146 (19) | 0.006 | 0.081 | 0.002 | 0.565 |
| Mean (SD) values on biochemistry: | ||||||||
| Haemoglobin (g/L) | 134 (18) | 137 (17) | 130 (17) | 134 (20) | <0.001 | <0.001 | <0.01 | <0.01 |
| Estimated GFR | 75 (25) | 81 (23) | 68 (26) | 69 (26) | <0.001 | <0.001 | <0.001 | >0.05 |
| Cholesterol (mmol/L) | 4.8 (1.3) | 4.9 (1.2) | 4.5 (1.5) | 4.8 (1.3) | <0.001 | <0.001 | >0.05 | <0.01 |
| Electrocardiographic changes: | ||||||||
| ST depression | 296 (14) | 70 (8) | 49 (14) | 177 (24) | <0.001 | <0.001 | <0.001 | <0.001 |
| ST elevation | 244 (12) | 10 (1) | 3 (1) | 231 (31) | <0.001 | 1.000 | <0.001 | <0.001 |
| T wave inversion | 305 (15) | 136 (14) | 70 (20) | 99 (15) | 0.008 | 0.008 | 0.724 | 0.005 |
| Bundle branch block | 219 (10) | 63 (6) | 67 (19) | 89 (12) | <0.001 | <0.001 | <0.001 | 0.002 |
| Mean (SD) TIMI risk score | 2.4 (1.5) | 1.7 (1.4) | 3.5 (1.2) | 3.3 (1.4) | <0.001 | <0.001 | <0.001 | >0.05 |
| Drugs on admission: | ||||||||
| Aspirin | 1065 (51) | 470 (48) | 213 (61) | 382 (51) | <0.001 | <0.001 | 0.191 | 0.003 |
| Clopidogrel | 242 (12) | 113 (11) | 53 (15) | 76 (10) | 0.056 | — | — | — |
| ß blockers | 682 (33) | 307 (31) | 141 (40) | 234 (31) | 0.005 | 0.003 | 1.000 | 0.004 |
| ACE inhibitors | 741 (35) | 302 (31) | 162 (46) | 277 (37) | <0.001 | <0.001 | 0.007 | 0.005 |
| Statins | 1054 (50) | 469 (48) | 220 (63) | 365 (49) | <0.001 | <0.001 | 0.663 | <0.001 |
IHD=ischaemic heart disease; GFR=glomerular filtration rate; TIMI=thrombolysis in myocardial infarction; ACE=angiotensin converting enzyme.
*Comparisons between groups of patients performed with analysis of variance for continuous variables with Tukey’s multiple comparison test between groups and χ2 test for categorical variables with Bonferroni correction to account for multiple comparisons in post hoc analysis (P<0.0167 indicates significance).