Asian patient speaking with doctor

Asian-Americans were more likely to experience a severe ischemic stroke and to have a worse outcome compared with white patients, according to preliminary research presented Thursday at the American Stroke Association’s International Stroke Conference.

An ischemic stroke occurs when a clot or mass clogs a blood vessel, cutting off blood flow to brain cells. The obstructions are caused by fatty deposits that line the vessel walls, a condition called atherosclerosis. Ischemic stroke accounts for about 87 percent of all strokes that occur in the U.S.

The study analyzed clinical data collected from 2004 through 2016 on 1.77 million Asian-American and white acute ischemic stroke patients at 2,171 hospitals participating in Get With The Guidelines-Stroke, a program developed by the American Heart Association/American Stroke Association. The program aims to improve stroke care by promoting consistent adherence to evidence-based treatment guidelines.

Close to 4 percent of the patients in the study were Asian-American, making it the largest analysis of outcomes for Asian-American patients admitted following a severe ischemic stroke.

The study found Asian-American ethnicity was associated with poorer functional recovery. It was also associated with receiving the clot-busting drug alteplase less frequently. The drug is used to improve a patient’s chances of recovering from a stroke. Yet, the study also found that Asian-Americans were more likely to have bleeding complications with the drug.

“Asian-Americans may have a distinctive pathophysiologic profile of ischemic stroke than whites,” said the study’s lead researcher Dr. Sarah Song, an assistant professor at Rush University Medical Center in Chicago, Illinois, in a press release. “This study highlights the need for more focused research, improved stroke prevention and possibly different treatment strategies for Asian-Americans.”

Overall, the study found that patient care improved between 2004 and 2016. Yet, said Song, there remain slight differences among Asian-Americans and whites. “Only whites had a decrease in trend in stroke severity,” said Song, “while Asian-Americans had a greater increase in timely administration” of the clot-busting drug.

The study looked at Asian-Americans as a whole, but there are differences among the various ethnic populations that make up this larger category. “Vietnamese people are not the same as Koreans, who are not the same as Japanese or South Asian groups,” said Song. These populations have different “stroke risk factors, diet and lifestyle, and other cultural factors.”

Still, said Song, the study “is a very good first step. This information gives us the urgency and the credibility to do more research in Asian-Americans.”

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