U.S. Counties With the Highest Stroke Death Rates

The South is home to the overwhelming majority of these 25 communities. Blood Flow Barrier

About 800,000 people in the United States experience a stroke every year, and having one increases the risk of having another, according to the Centers for Disease Control and Prevention.

Strokes occur either when blood traveling to the brain is blocked ñ an attack known as an ischemic stroke ñ or when a blood vessel inside the brain bursts, known as a hemorrhagic stroke. These incidents spark the death of brain tissue, according to the CDC, which then can cause brain damage, disability and death. Strokes kill about 140,000 Americans annually.

Among adults 35 and older, stroke death rates by county in recent years were especially high in the Southern U.S., a CDC map shows. High blood pressure, high cholesterol, smoking, obesity and diabetes are leading causes of stroke, the CDC reports, and "1 in 3 U.S. adults have at least one of these conditions or habits."

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About 80% of strokes are preventable, with high blood pressure the "single most important treatable risk factor," the CDC says. Eating a healthy diet low in sodium and featuring lots of fruits and vegetables, being physically active, not smoking and limiting alcohol consumption are lifestyle factors that can help people curb their risk of a stroke, according to the federal agency.

Anyone ñ including children ñ can have a stroke, though the risk of experiencing one increases with age. Based on publicly available CDC data, these are the counties and county equivalents with the highest age-adjusted death rates from strokes per 100,000 standard population in 2017, along with the ranking of their home state by stroke death rate.