By Aaron Allen, The Seattle Medium
For more than a century, medical research has predominantly focused on people of European descent, leaving significant gaps in understanding health conditions that affect Black and Brown communities. This lack of inclusive research has contributed to stark healthcare disparities and limited knowledge about treatments tailored to these groups, often resulting in poorer health outcomes.
One area where this gap is especially evident is in the study of atrial fibrillation (AFib), an irregular heart rhythm more common in older adults. While AFib can be diagnosed with an electrocardiogram (EKG) and managed with treatments like beta-blockers and electrical cardioversion, studies on its effects in Black adults remain scarce. A recent study led by Dr. Vid Yogeswaran, a cardiologist at the University of Washington School of Medicine, that was published on Oct. 30 in JAMA Network Open, seeks to address this gap by examining nearly 5,000 Black adults. The study’s findings reveal that each 10-beat-per-minute increase in resting heart rate is associated with a 9% greater risk of developing AFib—an association that highlights the urgent need for more diverse health research.
“This study is useful because, among Black adults, we know little about risk factors for cardiovascular disease—and specifically for AFib, which can lead to heart failure, stroke, dementia, and death,” said Dr. Yogeswaran. “Paradoxically, Black adults have a lower reported clinical prevalence of atrial fibrillation than White adults but have a much higher risk of AFib-associated consequences such as stroke and death.”
Historically, most health research in cardiology and other fields has focused primarily on White, European populations, overlooking the impact of conditions like AFib in other racial and ethnic groups. Dr. Yogeswaran pointed to a recent shift in the field toward studying more diverse populations.
“Most of those studies, like a lot of things in health care and cardiology, have really focused on populations of European descent,” she explained. “My mentor, Dr. James Floyd, is involved with several multiethnic cohort studies. So, they’re longitudinal population-based studies that take place across the United States that help us understand different risk factors for cardiovascular disease across diverse racial groups. The Jackson Heart Study is one of those large population-based research studies. They’re based out of a multi-county area in the greater Jackson, Mississippi area, and they’ve been following over 5,000 Black adults for more than 20 years. The study has been helpful in improving our understanding of cardiovascular risk factors unique to Black adults.”
AFib is the most common sustained cardiac arrhythmia in the U.S., affecting between 0.4% and 1% of the population. Known risk factors include high blood pressure, obesity, obstructive sleep apnea, diabetes, excessive alcohol consumption, and smoking—all of which are more common in Black adults than in White adults. Many of these risk factors are shaped by lifestyle, socioeconomic, and environmental influences, along with historical inequities that have left certain communities more vulnerable to these conditions.
“It’s not necessarily just aging, but essentially a lot of different changes to that top chamber of the heart, whether it’s obesity, whether it’s smoking, diabetes, sleep apnea, even hypothetically just being 28 and drinking a lot of alcohol can cause some structural changes and can lead to atrial fibrillation,” said Yogeswaran. “There are also some people that are genetically more likely to have atrial fibrillation. For a multitude of reasons, changes in the electricity and the structure of that top chamber (cardiac atria) may lead to atrial fibrillation.”
AFib is also a significant risk factor for stroke and dementia, which highlights the importance of early detection and management to prevent severe complications.
“The mechanism behind it (AFib) is really complicated,” says Yogeswaran. “But I do think one thing that’s important is a lot of people across different racial and ethnic groups may not recognize the signs of having atrial fibrillation. Some people can feel an irregular heart rate or feel like their heart is racing. I also think a lot of people don’t know that atrial fibrillation can lead to stroke. Sometimes, patients who come in for the first time discover they have atrial fibrillation after they’ve had a bad stroke. They tell us they didn’t notice any prior signs or didn’t understand the signs. My research interest is trying to figure out what early risk factors or signs can be used to detect which patients will be high risk for developing AFib.”
In addition to highlighting AFib’s risks, Dr. Yogeswaran’s study reflects a broader effort to address healthcare disparities and advance heart health for Black and Brown communities. Although her recent study was not specifically designed to directly confront these disparities, it builds foundational knowledge about cardiovascular risks for underrepresented populations.
“There are maybe 100 articles that have looked at resting heart rate as a risk factor for AFib, but none of them have focused on Black adults,” said Yogeswaran.
The limited representation of people of color in health studies restricts the medical community’s ability to provide Black and Brown communities with vital, data-driven information about their unique health risks.
“There are so many horrible health care disparities that disproportionately affect people of color, which is something that many of us want to try to fix by studying populations of color,” says Dr. Yogeswaran. “I think one way to fix those disparities is to help figure out whether there are unique risk factors in people of color. So, this study does not specifically say atrial fibrillation is more common in Black adults than we think, but it is saying resting heart rate is a risk factor that is important in Black adults, and Black adults with a high resting heart rate need to understand that they have a higher risk of atrial fibrillation.”
