Americans age 65 and younger are more than twice as likely to have a stroke compared with Caucasians（白种人） in any region, and people who have a stroke are more likely to die in the South than elsewhere, according to researchers at the University of Alabama at Birmingham (UAB) School of Public Health. The findings are from UAB's Reasons for Geographic and Racial Differences in Stroke (REGARDS) study, one of the largest ongoing health studies that includes more than 30,200 U.S. participants.

This new report is among the first to show major regional and racial disparities（不同，不等） in stroke rates. It also underscores the need for targeted stroke-prevention and care strategies in those at greatest risk, said Virginia Howard, Ph.D., a UAB associate professor of epidemiology（流行病学，传染病学） and a REGARDS co-principal investigator.

The study was presented Feb. 26 at the International Stroke Conference in San Antonio.

"This is the first study to take national data and really lay it out on the table," Howard said. "We found in the 45-54 age group that blacks have a 2.5-fold greater stroke rate compared to whites, which is startling."

The study also shows a stroke rate greater than 12 percent higher in eight Southeast states known as the Stroke Belt — Alabama, Arkansas, Georgia, Louisiana, Mississippi, North and South Carolina and Tennessee — with the highest stroke rate in the coastal states of Georgia, North and South Carolina.

"These are stroke-incidence data. It doesn't tell us how to fix the problem, but it gives us our clearest stroke picture to date in this country," Howard said.

In the new study, REGARDS researchers reviewed data on more than 26,500 participants with no history of stroke. They kept in periodic（周期的，定期的） telephone contact with the participants for nearly five years and documented 299 strokes to which they applied a rate formula. In the 45-54 age group, the stroke rate is 192 percent for African-Americans compared with 74 percent for whites.

"That disparity in the incidence rate evens out（使平坦，变正常） and changes as you monitor stroke in older Americans. In fact the racial differences reverse, so by the time they reach about age 80 and older, whites have a higher stroke rate compared with blacks," Howard said. It is not clear why the differences change with age, but it may have to do with different types of strokes occurring in different age groups.

The bottom line is that certain subgroups are at greater risk and need to pay closer attention to their stroke-risk factors, said George Howard, Dr.PH., a UAB professor of biostatistics（生物统计学） and a REGARDS co-principal investigator. Stroke-risk factors include family history, high blood pressure and high cholesterol, diabetes, obesity, tobacco use and other variables.