Stroke is the third leading cause of death in America, killing nearly one hundred and sixty thousand people every year. Additionally, approximately seven hundred and eighty Americans have a new or recurrent stroke each year and eight hundred and eighty five thousand discharges occur yearly for stroke management. Approximately five million people in the U.S. have had a stroke. Stroke is one of the leading causes of adult disability. Four million Americans are living with the effects of stroke. About one-third have mild impairments, another third are moderately impaired and the remainder are severely impaired. Stroke costs in the United States amount to $60 billion annually. Direct costs, such as hospitals, physicians and rehabilitation amount to $36 billion; indirect costs, such as lost productivity, total $25 billion.
Currently stroke is treated by enzymes, which break up clots and tissue plasminogen activator. However these drugs need to be administered within the initial few hours of the event to have success. Cholesterol lowering drugs such as Pravastatin reduce the risk of stroke and transient ischemic attacks by about thirty percent. Overall the death rate from stroke in the U.S. has declined by sixty percent during the past thirty years, largely due to treatments which control lipid levels and associated atherosclerotic plaque.
Ischemic strokes occur when an embolus detaches from the wall of an artery and lodges more distally blocking an artery in the brain. Ischemic strokes account for eighty five percent of strokes and recovery from these strokes is impaired by the release of metals and calcium resulting from mitochondrial damage.
However tissue is damaged in the aftermath of the event and rapid intervention in the aftermath to prevent mitochondrial damage and apoptois (programmed cell death) would facilitate early rehabilitation and reduce long term deficits and mortality. Brain tissue is particularly prone to oxidative damage post stroke because it lacks the presence of the anti oxidant uric acid which is present in other tissues of the body. Prevention of mitochondrial damage in the penumbral area of strokes in stroke models provides opportunity to hasten stroke recovery.