Stroke
Stroke
Stroke is a serious condition that occurs when blood flow to the brain is interrupted, either due to a blood clot in the brain (ischemic stroke) or a brain hemorrhage (hemorrhagic stroke). This interruption of blood supply results in damage to brain cells, which can have severe consequences. Stroke affects approximately 12,000 people per year in Denmark, with blood clots accounting for the majority (80-85%). Thus, stroke is one of the most common cardiovascular diseases in Denmark.
The mortality rate after stroke in Denmark is around 10% within 30 days, but many survivors experience disabling sequelae such as paralysis, speech difficulties, epilepsy, vision problems, neglect, cognitive difficulties, fatigue, depression, and more. Globally, stroke is one of the leading causes of both death and loss of healthy life years; in 2019, stroke was the second leading cause of death and the third leading cause of disability-adjusted life years (DALYs) worldwide, imposing significant costs on individuals and society.
Reperfusion therapies such as thrombolysis and thrombectomy have had markedly positive effects on the prognosis after ischemic stroke. Prior to these treatments, there were no evidence-based therapies to restore blood supply to ischemic brain tissue. The benefits of thrombolysis (medical treatment to dissolve the blood clot) within 3 hours of symptom onset were demonstrated in the NINDS study in 1995. Subsequent studies confirmed these results and showed a beneficial effect extending up to 4.5 hours after symptom onset, although faster treatment is associated with better outcomes. The benefits of thrombectomy (mechanical removal of the blood clot using a catheter) were first demonstrated two decades later. Like thrombolysis, the benefits of thrombectomy are greatest when administered promptly after symptom onset.
Unfortunately, many patients do not reach the hospital in time to receive reperfusion therapy. Several studies have shown that delay from symptom onset to hospital arrival is the primary reason why patients with brain clots do not receive reperfusion therapy. In Denmark, fewer than half of patients with ischemic stroke arrive within 4.5 hours of symptom onset. Despite having high reperfusion therapy rates internationally, only about a quarter of patients with ischemic stroke receive thrombolysis, thrombectomy, or both in Denmark.
Research in stroke conducted by the Danish Center for Health Services Research encompasses a range of projects carried out in collaboration with clinical colleagues both domestically and internationally. Examples of current and completed studies: