When stroke strikes, every minute’s delay of treatment counts. A huge new study now shows the exact benefit of early treatment.

Ischemic stroke occurs when a clot blocks blood flow to the brain. Two million brain cells die every minute until blood flow is restored. Infusion of the clot-busting drug known as tPA (tissue-type plasminogen activator) can restore blood flow to the brain. However, tPA must be infused in a hospital, as quickly as possible, and no later than 4.5 hours after the stroke.

Early treatment is known to be better, but how much better? Now we know, thanks to a study of over 58,000 patients treated with tPA in some 14,000 U.S. hospitals. Dr. Jeffrey L. Saver of UCLA and his co-authors, including Dr. Lee H. Schwamm of Harvard-affiliated Massachusetts General Hospital, reported the findings in The Journal of the American Medical Association.

For every 15-minute acceleration of time to tPA treatment, they found

• 4% lower risk of in-hospital death

• 4% better odds of walking independently after leaving the hospital

• 3% better odds of being sent home instead of to an institution

• 4% lower odds of a brain hemorrhage.

Taking an ambulance to the hospital makes it six times more likely a person will get early tPA treatment. Bottom line: know the warning signs of stroke and have a action plan for what to do in the event of this life-threatening but treatable emergency.