Table 1.
Baseline characteristics
| rt-PA (n=1515) | Control(n=1520) | ||
|---|---|---|---|
| Baseline variables collected before treatment allocation* | |||
| Region† | |||
| Northwest Europe (UK, Austria, Belgium, Switzerland) | 792 (52%) | 797 (52%) | |
| Scandinavia (Norway, Sweden) | 251 (17%) | 250 (16%) | |
| Australasia | 89 (6%) | 90 (6%) | |
| Southern Europe (Italy, Portugal) | 204 (13%) | 204 (13%) | |
| Eastern Europe (Poland) | 174 (11%) | 173 (11%) | |
| Americas (Canada, Mexico) | 5 (<1%) | 6 (<1%) | |
| Age (years)‡ | |||
| 18–50 | 59 (4%) | 68 (4%) | |
| 51–60 | 98 (6%) | 104 (7%) | |
| 61–70 | 188 (12%) | 177 (12%) | |
| 71–80 | 353 (23%) | 371 (24%) | |
| 81–90 | 706 (47%) | 701 (46%) | |
| >90 | 111 (7%) | 99 (7%) | |
| Sex† | |||
| Female | 782 (52%) | 788 (52%) | |
| NIHSS† | |||
| 0–5 | 304 (20%) | 308 (20%) | |
| 6–10 | 422 (28%) | 430 (28%) | |
| 11–15 | 306 (20%) | 295 (19%) | |
| 16–20 | 270 (18%) | 273 (18%) | |
| >20 | 213 (14%) | 214 (14%) | |
| Delay in randomisation†‡ | |||
| 0–3·0 h | 431 (28%) | 418 (28%) | |
| 3·0–4·5 h | 577 (38%) | 600 (39%) | |
| 4·5–6·0 h | 507 (33%) | 500 (33%) | |
| >6·0 h | 0 (0%) | 2 (<1%) | |
| Atrial fibrillation | 473 (31%) | 441 (29%) | |
| Systolic blood pressure | |||
| ≤143 mm Hg | 487 (32%) | 492 (32%) | |
| 144–164 mm Hg | 498 (33%) | 518 (34%) | |
| ≥165 mm Hg | 530 (35%) | 510 (34%) | |
| Diastolic blood pressure§ | |||
| ≤74 mm Hg | 462 (31%) | 445 (29%) | |
| 75–89 mm Hg | 541 (36%) | 588 (39%) | |
| ≥90 mm Hg | 500 (33%) | 480 (32%) | |
| Blood glucose¶ | |||
| ≤5 mmol/L | 254 (18%) | 285 (21%) | |
| 6–7 mmol/L | 664 (48%) | 638 (46%) | |
| ≥8 mmol/L | 455 (33%) | 456 (33%) | |
| Treatment with antiplatelet drugs in previous 48 h† | 775 (51%) | 787 (52%) | |
| Predicted probability of poor outcome at 6 months‖ | |||
| <40% | 351 (23%) | 378 (25%) | |
| 40–50% | 169 (11%) | 160 (11%) | |
| 50–75% | 361 (24%) | 357 (23%) | |
| ≥75% | 634 (42%) | 625 (41%) | |
| Stroke clinical syndrome†** | |||
| TACI | 639 (42%) | 666 (44%) | |
| PACI | 596 (39%) | 551 (36%) | |
| LACI | 168 (11%) | 164 (11%) | |
| POCI | 110 (7%) | 136 (9%) | |
| Other | 2 (<1%) | 3 (<1%) | |
| Baseline variables collected from prerandomisation scan | |||
| Expert reader's assessment of acute ischaemic change†† | ‥ | ‥ | |
| Scan completely normal | 140 (9%) | 129 (8%) | |
| Scan not normal but no sign of acute ischaemic change | 743 (49%) | 781 (51%) | |
| Signs of acute ischaemic change | 624 (41%) | 600 (40%) | |
Data are number (%). Percentages exclude missing values from denominators. rt-PA=recombinant tissue plasminogen activator. NIHSS=National Institutes of Health Stroke Scale. TACI=total anterior circulation infarct. PACI=partial anterior circulation infarct. LACI=lacunar infarct. POCI=posterior circulation infarct.
Data for these variables were gathered via the web-based or telephone randomisation system and had to be entered, complete, and have passed range and consistency checks before the system would issue a treatment allocation.
Variables were used in the minimisation algorithm.
Two patients in the control group were randomly assigned at more than 6 h (protocol violation). One of these was recorded as having severe swelling on the randomisation scan, because the stroke had in fact occurred about 24 h earlier.
Diastolic blood pressure missing for 12 patients in the rt-PA group and seven in the control group.
For the first 282 patients, glucose levels were not recorded. After patient 282, glucose levels were measured at randomisation. One further patient had a missing value.
Risk predicted by novel model designed by Konig and colleagues.18 This model predicts outcome (death or Bartel Index <95) at 3 months. If we assume that those who die between 3 months and 6 months were dependent at 3 months, and those who do not die between 3 months and 6 months do not change their dependency status, then the risk estimates are likely to be quite accurate for death or dependency at 6 months.
Stroke clinical syndrome derived from baseline clinical features assigned by an algorithm (algorithm available on request). For the randomisation algorithm TACI, PACI, and POCI were combined as non-lacunar so the process ensured balance in the number of lacunar syndromes in each treatment group.
Expert panel's masked assessment of prerandomisation scan. This assessment was done by members of the expert panel after randomisation and masked to treatment allocation and all clinical details. Prerandomisation scans were unavailable for eight patients in the rt-PA group and ten in the control group.