Table 1.
Baseline Patient Characteristics, Before and After Propensity Score Matching
| Before matching | After matching | ||||
|---|---|---|---|---|---|
| N (%) or mean (±SD) | Random Placebo (N=982) | P | Digoxin at SDC 0.5–0.9 (N=982) | P | Matched Placebo (N=982) |
| Age (years) | 64.2 (±10.8) | 0.004 | 62.8 (±10.6) | 0.834 | 62.7 (±11.2) |
| Age ≥65 years | 520 (53.0%) | 0.034 | 472 (48.1%) | 0.558 | 460(46.8%) |
| Female | 236 (24.0%) | 0.335 | 217 (22.1%) | 0.348 | 199 (20.3%) |
| Non-white | 162 (16.5%) | 0.025 | 126 (12.8%) | 1.000 | 126 (12.8%) |
| Body mass index, kg/square meter | 27.6 (±5.14) | 0.080 | 27.2 (±5.03) | 0.136 | 26.8 (±5.0) |
| Duration of HF (months) | 31.1 (±38.1) | 0.540 | 32.2 (±38.7) | 0.251 | 30 (±37) |
| Primary cause of HF | |||||
| Ischemic | 683 (69.6%) | 672 (68.4%) | 677 (68.9%) | ||
| Hypertensive | 98 (10.0%) | 98 (10.0%) | 90 (9.2%) | ||
| Idiopathic | 133 (13.5%) | 0.799 | 148 (15.1%) | 0.922 | 147 (15.0%) |
| Others | 68 (6.9%) | 64 (6.5%) | 68 (6.9%) | ||
| Comorbid conditions | |||||
| Prior myocardial infarction | 629 (64.1%) | 0.851 | 624 (63.5%) | 0.708 | 615 (62.6%) |
| Current angina | 277 (28.2%) | 0.479 | 262 (26.7%) | 0.759 | 256 (26.1%) |
| Hypertension | 485 (49.4%) | 0.021 | 433 (44.1%) | 1.000 | 432 (44.0%) |
| Diabetes | 294 (29.9%) | 0.147 | 265 (27.0%) | 0.235 | 241 (24.5%) |
| Chronic renal dysfunctioin | 460 (46.8%) | <0.0001 | 368 (37.5%) | 0.745 | 376 (38.3%) |
| Dose of study medication | 0.246 (±0.07) | 0.596 | 0.244 (±0.07) | 0.317 | 0.247 (±0.07) |
| Medications | |||||
| Pre-trial digoxin use | 409 (41.6%) | 0.033 | 457 (46.5%) | 0.104 | 494 (50.3%) |
| ACE inhibitors | 917 (93.4%) | 0.213 | 931 (94.8%) | 0.920 | 930 (94.7%) |
| Diuretics | 768 (78.2%) | 0.006 | 715 (72.8%) | 0.650 | 705 (71.8%) |
| Symptoms and signs of heart | |||||
| Dyspnea at rest | 225 (22.9%) | 0.077 | 192 (19.6%) | 0.820 | 188 (19.1%) |
| Dyspnea on exertion | 736 (74.9%) | 0.470 | 721 (73.4%) | 0.760 | 714 (72.7%) |
| Jugular venous distension | 133 (13.5%) | 0.172 | 112 (11.4%) | 1.000 | 113 (11.5%) |
| Third heart sound | 234 (23.8%) | 0.674 | 243 (24.7%) | 0.793 | 237 (24.1%) |
| Pulmonary râles | 149 (15.2%) | 0.368 | 134 (13.6%) | 0.791 | 129 (13.1%) |
| Lower extremity edema | 207 (21.1%) | 0.193 | 183 (18.6%) | 0.954 | 185 (18.8%) |
| NYHA functional class | |||||
| I | 141 (14.4%) | 173 (17.6%) | 181 (18.4%) | ||
| II | 558 (56.8%) | 0.273 | 536 (54.6%) | 0.845 | 524 (53.4%) |
| III | 268 (27.3%) | 259 (26.4%) | 259 (26.4%) | ||
| IV | 15 (0.8%) | 14 (1.4%) | 18 (1.8%) | ||
| Heart rate (/minute), | 78.3 (±12.4) | 0.067 | 77.2 (±12.7) | 0.329 | 77.8 (±12.5) |
| Blood pressure (mm Hg) | |||||
| Systolic | 127.8 (±20.0) | 0.171 | 126.6 (±19.8) | 0.926 | 126.5 (±20.0) |
| Diastolic | 75.2 (±11.3) | 0.543 | 75.6 (±10.8) | 0.753 | 75.4 (±11.1) |
| Chest radiograph findings | |||||
| Pulmonary congestion | 128 (13.0%) | 0.372 | 114 (11.6%) | 0.780 | 119 (12.1%) |
| Cardiothoracic ratio >0.5 | 586 (59.7%) | 0.217 | 558 (56.8%) | 0.891 | 554 (56.4%) |
| Serum creatinine (mg/dL) | 1.28 (±0.37) | <0.0001 | 1.21 (±0.32) | 0.675 | 1.22 (±0.32) |
| Ejection fraction (%) | 31.9 (±12.5) | 0.958 | 31.9 (±12.1) | 0.554 | 31.6 (±12.5) |
| Ejection fraction >45% | 130 (113.2%) | 0.146 | 108 (11.0%) | 0.670 | 115 (11.7%) |