An earlier treatment means a better recovery for patients with stroke
Stroke is a medical emergency and early treatment is essential for patient recovery. Therefore, bringing the patient in time, after the stroke occurs, to the emergency room for specific treatment (fibrinolysis), is crucial. But so far there have been limited information regarding how the timing of administration of tissue plasminogen activator, or tPA, influences the outcome of patients with ischemic stroke, the most common type of stroke. Now a team of researchers from the University of California, Los Angeles conducted a study on more than 50 000 stroke patients treated with tPA. They wanted to see how critical is the timing between stroke onset and treatment.
Dr. Jeffrey Saver, a professor of neurology and director of the UCLA Stroke Center, said they found that the timing of the treatment had a strong influence on recovery and that the faster the treatment was applied, the better the results. He also added the patients who receive early treatment recovers much better: “Beginning treatment earlier resulted in an improved ability to walk, the ability to remain living independently, less bleeding in the brain and reduced mortality.”
Previous studies have demonstrated that intravenous tPA up to 4.5 hours after stroke helps patients with moderate to severe acute ischemic stroke. The data so far show that the maximum benefit comes when patients are treated very early after stroke and that it starts to decrease after 4.5 hours. But the disadvantage is that these data were drawn from a relatively small number of studies (eight studies conducted on 1,850 patients treated with tPA) and cannot be extrapolated to the general population. Therefore, the study conducted by researchers at UCLA used a large national registry to determine more accurately the association between time to treatment and stroke.
The study was conducted on a sample of 58 353 patients with acute ischemic stroke treated with tPA in the first 4.5 hours from stroke. The average patient age was 72 years and the average time from the onset of stroke to treatment was 144 minutes (about 2 hours and a half). After analyzing the medical history of the patients, the researchers were able to confirm precisely how critical is the time gap between the occurrence of stroke and receiving treatment. Saver pointed out that they knew from imaging investigations that the volume of irreversibly damaged brain tissue after ischemic stroke is expanding rapidly over time and that it takes more than 2 million neurons per minute for additional blood flow in the brain to be restored.