The independent analysis of trial data for thrombolysis in stroke commissioned by ACEM has been released via their website. This review will influence the upcoming position paper on the topic being developed by the college, with an independent review sought "due to concern that many of the studies and previous reviews have been conducted by investigators with potential conflicts of interest".
This review looked only at the use of alteplase, and could not include IST-3 in meta-analysis due to different eligibility, methodology and outcomes to the other trials.
A summary of findings is available, as well as the full report. The key points to me were:
- NNT = 10 for modified Rankin Score (mRS) of 0-1 (return to baseline) for thrombolysis within 4.5 hours
- Treatment within 3 hours has greater advantage for this outcome than between 3 - 4.5 hours
- NNH = 42 for symptomatic ICH (with large confidence intervals 13-119)
- No difference in mortality at 30 days
But wait, there's more
The kicker, for me, though, was that if you extend the outcomes to include mRS 0-2, that is, if you accept mild disability whilst remaining independent (mRS = 2), there is no benefit from thrombolysis, although a significant risk of ICH remains. This then becomes a question of the value placed on the difference between a return to baseline and a slight disability. The summary concludes:
Therefore, discussion with patient and family/carers by the treating clinicians, and informed consent is vital to any decision about use of thrombolytic therapy in stroke
What about bias?
It is again highlighted that all of these data have significant industry investment in their publication:
All studies were drug company funded, which, whilst not automatically problematic, does raise doubt around the objectivity of the published work... the most influential literature in this area is all susceptible to sponsorship bias, indicating the need for independent, placebo-controlled studies
So the question is, will this change your practice of thrombolysis?
Will you include these points in your discussion with patients and family?
Or will you wait to see the position paper?