Gregory M. Marcus
People of American Indian ancestry have significantly greater risk for atrial fibrillation compared with white, black, Hispanic and Asian individuals, according to a study published in Circulation.
Researchers found that the overall incidence of AF in American Indian people was 7.49 per 1,000 person-years compared with 6.89 per 1,000 person-years for people of any other race or ethnicity (P < .0001).
Sensitivity analyses were restricted to individuals with encounters in only EDs or inpatient hospital units, and to adults aged at least 35 years who had at least two hospital visits produced similar results, according to the researchers.
“We were surprised to find that American Indians experienced a higher risk of AF compared to every other racial and ethnic group,” Gregory M. Marcus, MD, MAS, endowed professor of AF research at the University of California, San Francisco, said in a press release. “Understanding the mechanisms and factors by which American Indians experience this higher risk may help investigators better understand the fundamental causes of atrial fibrillation that prove useful to everyone at risk for AF, regardless of their race or ethnicity.”
In other findings, researchers found that the elevated risk for AF was attenuated by the presence of diabetes and chronic kidney disease in the American Indian group.
“This may suggest that the presence of these two processes contributes some pathophysiology related to AF risk that may be similar to the heightened risk inherent among American Indians,” the researchers wrote. “It is also important to note that there was no evidence of any other statistically significant interactions despite the inclusion of millions of patients.”
Researchers used data from the Healthcare Cost and Utilization Project California State Databases to identify more than 16 million California residents aged at least 18 years, who received care in an ED, inpatient hospital unit or ambulatory surgery setting between 2005 and 2011. According to the study, approximately 0.6% of the cohort was American Indian, 57.2% was white, 8% was black, 25.6% was Hispanic and 8.6% was Asian.
Patients with preexisting AF were excluded from the analysis.
“The heightened risk of AF in American Indians persisted after multivariable adjustment for known conventional confounders and mediators, suggesting that an unidentified characteristic, including possible genetic or environmental factors, may be responsible,” Marcus and colleagues wrote. – by Scott Buzby
Disclosure s : Marcus reports he received research support from Baylis, Eight, Jawbone and Medtronic and is a consultant for and holds equity in InCarda. The other authors report no relevant financial disclosures.