High stroke risk among American Indians not solely due to AFib, research suggests

By American Heart Association News

grandriver/E+, Getty Images
(grandriver/E+, Getty Images)

Researchers trying to understand why stroke risk is higher among American Indian adults may be able to cross one reason off the list: the presence of a quivering or irregular heartbeat known as atrial fibrillation.

New research, published this week in the Journal of the American Heart Association, found American Indian adults had a higher risk of stroke caused by a clot than people from any other racial or ethnic group, regardless of whether they also experienced AFib.

"The results of our study add to the growing body of evidence that race and ethnicity are important factors when assessing stroke risk," the study's senior author, Dr. Gregory Marcus, said in a news release. Marcus is a professor of medicine and chief of cardiology for research at the University of California, San Francisco.

"However, our findings that conventional risk factors such as AFib may not be the cause for this increased risk among American Indian individuals suggest other influences are in play. These could possibly be related to hereditary factors, environmental exposures or disparities in access to health care, and this clearly warrants further attention."

AFib when left untreated can greatly increase the risk of stroke. Previous research shows American Indian people have the highest risk of AFib than any other racial or ethnic group, Marcus said.

In the new study, researchers analyzed data for 17 million adults treated at hospitals in California. They found that among people with AFib, American Indian adults had a 38% higher risk of stroke than Black, Hispanic, Asian and white adults. Among those without AFib, American Indian adults had a 59% higher risk of stroke, suggesting that AFib alone was not responsible for the higher stroke risk.

Lower rates of health insurance, lower incomes and higher rates of risk factors for stroke, such as obesity, diabetes and smoking, likely contributed to the problem among American Indian adults, the researchers found.

Regular preventive care, including routine screening and treatment for high blood pressure, Type 2 diabetes and AFib, could reduce the higher risk for stroke in this population, Marcus said. But "there remains the challenge of determining optimal methods to actually implement these strategies in the real world that can improve people's health and lives."

If you have questions or comments about this story, please email [email protected].

American Heart Association News Stories

American Heart Association News covers heart disease, stroke and related health issues. Not all views expressed in American Heart Association News stories reflect the official position of the American Heart Association. Statements, conclusions, accuracy and reliability of studies published in American Heart Association scientific journals or presented at American Heart Association scientific meetings are solely those of the study authors and do not necessarily reflect the American Heart Association’s official guidance, policies or positions.

Copyright is owned or held by the American Heart Association, Inc., and all rights are reserved. Permission is granted, at no cost and without need for further request, for individuals, media outlets, and non-commercial education and awareness efforts to link to, quote, excerpt from or reprint these stories in any medium as long as no text is altered and proper attribution is made to American Heart Association News.

Other uses, including educational products or services sold for profit, must comply with the American Heart Association’s Copyright Permission Guidelines. See full terms of use. These stories may not be used to promote or endorse a commercial product or service.

HEALTH CARE DISCLAIMER: This site and its services do not constitute the practice of medical advice, diagnosis or treatment. Always talk to your health care provider for diagnosis and treatment, including your specific medical needs. If you have or suspect that you have a medical problem or condition, please contact a qualified health care professional immediately. If you are in the United States and experiencing a medical emergency, call 911 or call for emergency medical help immediately.