Disparities Seen in Use of Standard of Care Blood Thinners for Atrial Fibrillation

By Linda Carroll

July 29, 2021

(Reuters Health) - Minority patients with atrial fibrillation are less likely to be treated with standard of care blood thinners than white patients, a new study of U.S. Veterans Administration data suggests.

Based on data from 111,666 patients receiving treatment within the VA system, researchers found that, compared with white patients, Black patients were 26% less likely, Hispanic patients 21% less likely, and Native American/Alaska Native 25% less likely to receive direct-acting oral anticoagulants after an index diagnosis of atrial fibrillation, according to the results in JAMA Network Open.

"The biggest take-home message from this study is the finding that Black, Hispanic and American Indian/Alaska Natives are less likely to get the newer class of medications to prevent stroke from occurring," said Dr. Utibe Essien, an assistant professor at the University of Pittsburgh School of Medicine and health services researcher at the VA Pittsburgh Healthcare System Center for Health Equity Research and Promotion.

And this is occurring at the VA, where there has been really improved access to medications, Dr. Essien said. "To see this occurring in these subgroups even now is really concerning," he added.

To take a closer look at treatment received by patients with atrial fibrillation, Dr. Essien and his colleagues turned to the Race, Ethnicity and Anticoagulant Choice in Atrial Fibrillation (REACH-AF), a national, retrospective cohort of patients enrolled in the VA system with incident, nonvalvular atrial fibrillation from 2010 through 2018.

For their analysis, the researchers used administrative and clinical data from the VA Corporate Data Warehouse, which contains information on outpatient and inpatient clinical encounters including patient sociodemographic details, diagnosis codes, VAS clinic stop codes, and all prescribed medications dispensed by VA pharmacies.

The cohort comprised 111,666 patients, of whom 109,386 were men (98.0%), 2,280 were women (2.0%), and 95,493 were white (85.5%), with a mean age of 72.9 years. Other racial/ethnic groups in decreasing frequency were Black (9.2%), Hispanic (3.7%), Asian (1.6%), and AI/AN (0.5%). The majority of patients had a moderate (62.9%) or high (24.3%) stroke risk.

A total of 69,590 patients (62.3%) initiated any anticoagulant therapy within 90 days of an index atrial fibrillation diagnosis, with initiation rates lowest in Asian (52.2%) and Black (60.3%) patients, and highest in white patients (62.7%).

Among anticoagulant initiators, 45,381 (65.2%) used direct-acting oral anticoagulants, with initiation rates lowest in Hispanic (58.3%), American Indian/Alaska Native (59.8%), and Black (60.9%) patients, and highest in white patients (66.0%). Compared with white patients, the odds of initiating any anticoagulant therapy were significantly lower for Asian (adjusted odds ratio 0.82) and Black (aOR 0.90) patients.

Among initiators, the adjusted odds of direct-acting oral anticoagulant initiation were significantly lower for Hispanic (aOR 0.79), American Indian/Alaska Native (aOR 0.75), and Black (aOR 0.74) patients.

It's possible that minority patients might be less likely to initiate therapy for a variety of reasons, including distrust of the medical system as a whole, said Dr. Peter Meunnig, a professor of health policy and management at Columbia University's Mailman School of Public Health in New York City.

But the fact that among patients who are initiating therapy there are racial and ethnic disparities with regard to which anticoagulant is prescribed, "that's a big deal," Dr. Meunnig said, adding that it's important to figure out why this is happening.

"My guess is it has to do with variations in the quality of care in the VA system," Dr. Meunnig said.

SOURCE: https://bit.ly/2V2DBIO JAMA Network Open, online July 28, 2021.