Of those who have a stroke, at least 10% will have another stroke within the year. After 5 years more than 30% will have had another stroke. However it has been shown that these individuals can decrease their risk of a second stroke by 50% with anticoagulation therapy and by addressing their risk factors--especially hypertension, atrial fibrillation, and cigarette smoking. For those who have had a TIA, their outlook is even more favorable. Many of these same medical and surgical treatments can now significantly reduce the risk that they will go on to have a stroke.