A haemorrhagic stroke occurs because of an intra-cerebral haemorrhage (ICH) and one review has estimated a 1-year survival level of 46% and a 5-year survival of 29%.
Furthermore, such survivors are not only at a higher risk of a further stroke but other cardiovascular events such as myocardial infarctions. With a heightened risk of future cardiovascular events after a haemorrhagic stroke, there is some uncertainty over the value of post-stroke anti-platelet therapy. This is in part due to clinician reluctance to continue with anti-platelet therapy because of the elevated risk of a further haemorrhagic stroke, particularly with drugs such as aspirin.
In an effort to provide some much needed clarity over the safety of continued anti-platelet therapy, a team from the Centre for Clinical Brain Sciences, University of Edinburgh, UK, undertook the Restart or stop Antithrombotics Randomised Trial (RESTART). This trial included patients who had suffered a haemorrhagic stroke while taking anti-platelet therapy (aspirin, clopidogrel and dypridamole) but who then discontinued their drug. For the purposes of the RESTART trial, patients were randomised to either re-starting an anti-platelet or to avoid further use. After a median follow-up period of 2 years, there was a slight, non-significant (p = 0.06) decreased risk of recurrent stroke among those taking anti-platelet drugs. The RESTART team have now released findings from a follow-up study of those involved in the original trial. For the follow-up study, the primary outcome was fatal or non-fatal radiologically or pathologically proven recurrent symptomatic ICH. The secondary outcomes included major haemorrhagic events and major occlusive vascular events.
In the original RESTART trial, 537 patients with a median age of 76 years (67% male) were randomised to restart (268) or avoid (269) anti-platelet therapy, a median of 76 days after the onset of their stroke. In the follow-up trial, which lasted a median of 3 years (i.e., 5 years from the original trial), 562 of those from RESTART consented to continue and were randomised as before to re-start anti-platelet therapy (268) or avoid it (268). The primary outcome occurred in 8.2% of those taking an anti-platelet and 9.3% without treatment (adjusted hazard ratio, aHR = 0.87, 95% CI 0.49–1.55, p = 0.64). For the secondary outcomes there was also no significant difference (aHR = 0.79, 95% CI 0.58–1.08, p = 0.14).
These findings provide physicians with some reassurance about the use of antiplatelet therapy after ICH if indicated for secondary prevention of major vascular events.
Salman RA et al. Effects of Anti-platelet Therapy After Stroke Caused by Intracerebral Hemorrhage. Extended Follow-up of the RESTART Randomized Clinical Trial. JAMA Neurol 2021.