Table 1.
Characteristics of patients with an uncomplicated initial acute myocardial infarction according to length of hospital stay: Worcester Heart Attack Study
| Variables | ≤2 days (n= 572) |
3 days (n=386) |
≥4 days (n= 543) |
p1 | p2 |
|---|---|---|---|---|---|
| Age (years) | 59 [53–70] | 62 [51–73] | 69 [57–78] | 0.15 | <0.001 |
| Age | 0.09 | <0.001 | |||
| <55 | 189 (33.0%) | 122 (31.6%) | 114 (21.0%) | ||
| 55–64 | 171 (29.9%) | 92 (23.8%) | 104 (19.2%) | ||
| 65–74 | 111 (19.4%) | 88 (22.8%) | 124 (22.8%) | ||
| ≥75 | 101 (17.7%) | 84 (21.8%) | 201 (37.0%) | ||
| Men | 405 (70.8%) | 246 (63.7%) | 295 (54.3%) | 0.021 | 0.004 |
| White | 510 (92.4%) | 338 (91.4%) | 468 (90.4%) | 0.57 | 0.61 |
| Transferred from other hospitals | 86 (15.0%) | 46 (11.9%) | 52 (9.6%) | 0.17 | 0.25 |
| Angina pectoris | 41 (7.2%) | 36 (9.3%) | 65 (12.0%) | 0.23 | 0.20 |
| Atrial fibrillation | 30 (5.2%) | 22 (5.7%) | 61 (11.2%) | 0.76 | 0.004 |
| Chronic obstructive pulmonary disease | 49 (8.6%) | 43 (11.1%) | 85 (15.7%) | 0.19 | 0.049 |
| Chronic kidney disease | 32 (5.6%) | 27 (7.0%) | 88 (16.2%) | 0.38 | <0.001 |
| Diabetes mellitus | 127 (22.2%) | 101 (26.2%) | 160 (29.5%) | 0.16 | 0.27 |
| Heart failure | 16 (2.8%) | 17 (4.4%) | 37 (6.8%) | 0.18 | 0.12 |
| Hypertension | 359 (62.8%) | 241 (62.4%) | 382 (70.4%) | 0.92 | 0.011 |
| Peripheral artery disease | 49 (8.6%) | 37 (9.6%) | 66 (12.2%) | 0.59 | 0.22 |
| Stroke/Transient ischemic attack | 33 (5.8%) | 33 (8.6%) | 59 (10.9%) | 0.10 | 0.24 |
| ST-segment elevation myocardial infarction | 178 (31.1%) | 150 (38.9%) | 180 (33.2%) | 0.013 | 0.07 |
| Admission presentation | |||||
| Heart rate (bpm) | 80 [68–90] | 80 [67–92] | 82 [70–99] | 0.57 | 0.006 |
| Systolic blood pressure (mmHg) | 149 [130–165] | 143 [124–162] | 142 [122–162] | 0.023 | 0.71 |
| Troponin I (ng/ml) | 0.27 [0.09–1.40] | 0.45 [0.10–3.30] | 0.66 [0.10–4.20] | 0.001 | 0.17 |
| Glomerular filtration rate (ml/min) | 61.0 [60.0–79.9] | 63.8 [58.0–80.6] | 60.3 [50.2–78.4] | 0.82 | 0.003 |
| Glucose (mg/dl) | 127 [108–158] | 130 [109–165] | 136 [111–181] | 0.29 | 0.05 |
| White blood cell count (109 cell/L) | 8.7 [7.0–10.6] | 9.0 [7.2–11.3] | 9.5 [7.3–12,3] | 0.15 | 0.028 |
| Medical treatment | |||||
| Angiotensin converting enzyme inhibitor/Angiotensin receptor blocker | 388 (67.8%) | 274 (71.0%) | 397 (73.1%) | 0.30 | 0.48 |
| Aspirin | 549 (96.0%) | 372 (96.4%) | 518 (95.4%) | 0.76 | 0.46 |
| Beta-blockers | 527 (92.1%) | 363 (94.0%) | 507 (93.4%) | 0.26 | 0.68 |
| Diuretics | 90 (15.7%) | 70 (18.1%) | 148 (27.3%) | 0.33 | 0.001 |
| Statins | 449 (78.5%) | 326 (84.5%) | 422 (77.7%) | 0.021 | 0.011 |
| Percutaneous coronary intervention | 403 (70.5%) | 274 (71.0%) | 314 (57.8%) | 0.86 | <0.001 |
p-values from Chi-square and Fisher’s-exact test for categorical variables, and Kruskal-Wallis test for continuous variables, p1: compares hospital discharge at ≤2 days vs. 3 days, p2: compares hospital discharge at 3 days vs. ≥4days