silent stroke
Stroke trials address both acute treatment (revascularization within hours of onset) and long-term secondary prevention, with rehabilitation science emerging as a distinct research priority. Advances in thrombectomy techniques have dramatically improved outcomes for large vessel occlusion strokes, driving trials to push the treatment window from 6 to 24 hours in selected patients.
Current research includes tenecteplase vs alteplase for thrombolysis, thrombectomy for medium vessel occlusions, neuroprotective agents, factor XIa inhibitors for secondary prevention with lower bleeding risk, and telerehabilitation using robotics and brain-computer interfaces. Trials in wake-up stroke and unknown time-of-onset have expanded using MRI mismatch criteria.
Disease Burden & Epidemiology
Stroke is the second leading cause of death and the third leading cause of disability globally. The WHO estimates approximately 15 million strokes occur worldwide each year, of which 5 million result in death and 5 million in permanent disability. In the United States, approximately 795,000 people experience a stroke annually — one every 40 seconds — including approximately 610,000 first strokes and 185,000 recurrent strokes. Ischemic stroke (caused by arterial occlusion) accounts for approximately 87% of all strokes; hemorrhagic stroke (caused by vessel rupture) accounts for the remainder and carries a significantly higher short-term mortality. Stroke disproportionately affects older adults: risk doubles every decade after age 55, and two-thirds of stroke hospitalizations are in adults over 65. However, the rate of stroke in young adults (ages 18–50) has risen in recent decades, partly attributed to rising rates of obesity, hypertension, and atrial fibrillation in younger populations. Racial and ethnic disparities are substantial: Black Americans have a stroke rate more than double that of white Americans and a higher stroke mortality rate at every age. Annual stroke-related costs in the United States exceed $56 billion.
Key Research Trends & Landmark Studies
The MR CLEAN, ESCAPE, EXTEND-IA, and SWIFT PRIME trials β€” published simultaneously in 2015 β€” established mechanical thrombectomy as standard of care for large vessel occlusion ischemic stroke within 6 hours, overturning prior trial failures and representing the most significant acute stroke advance in decades. DAWN and DEFUSE 3 extended the thrombectomy window to 24 hours in perfusion-imaging-selected patients, dramatically expanding the eligible population. The THALES trial established ticagrelor plus aspirin dual antiplatelet therapy for minor stroke and TIA. In secondary prevention, the SOCRATES and POINT trials refined dual antiplatelet regimens for early recurrence prevention after transient ischemic attack. Currently, the BRAIN-AF trial is examining the yield of prolonged cardiac monitoring after cryptogenic stroke, the EXCEL stroke prevention trial is evaluating inclisiran (RNA interference LDL-lowering) versus standard care, and multiple factor XIa inhibitor programs (milvexian, abelacimab) aim to reduce stroke risk with lower bleeding than current anticoagulants.
Patient Guide: How to Find & Join a Trial
Stroke clinical trials cover three distinct phases: acute treatment (enrollment within hours), post-acute rehabilitation (days to months), and long-term secondary prevention (ongoing). Acute stroke trials require rapid identification and enrollment at stroke-certified hospitals β€” if you or a family member is at high stroke risk or has had a TIA, identify the nearest comprehensive stroke center in advance. For rehabilitation trials, the optimal window for enrollment is typically within the first 6 months of stroke, when neuroplasticity is highest. For secondary prevention trials β€” the largest category by enrollment β€” any adult with a prior ischemic stroke or TIA may be eligible, and these trials are often conducted in outpatient neurology settings including community practices. Know your stroke details before meeting a neurologist: date and time of symptom onset, imaging findings (CT/MRI results), etiology if established (cardioembolic, large vessel, small vessel, or cryptogenic), current antiplatelet or anticoagulation therapy, and any cardiac evaluation results including echocardiogram and ambulatory heart rhythm monitoring.