Disparities Seen in Uptake of DOACs for VTE

Even in a commercially insured population of patients hospitalized for venous thromboembolism (VTE), certain groups are lagging behind in terms of prescriptions for direct oral anticoagulants (DOACs), a new US study shows.

Although there was a large overall increase in DOAC prescriptions over time, black patients and those who had a low household income were less likely to receive them, Ashwin Nathan, MD (Hospital of the University of Pennsylvania, Philadelphia), reported Friday at the American Heart Association’s Quality of Care and Outcomes Research (QCOR) 2019 Scientific Sessions in Arlington, VA.

“We as treating providers need to be cognizant of these inequities that may exist and do whatever we can to mitigate them,” Nathan told TCTMD. “One of the things this study emphasizes is the importance of efforts to ensure that all races, ethnicities, and socioeconomic groups are treated equally and fairly.”

Chair of the QCOR meeting Adrian Hernandez, MD (Duke Clinical Research Institute, Durham, NC), pointed out that there are often racial, socioeconomic, and other types of disparities in how novel innovations in medicine—like DOACs—are rolled out.

“This is another example of that, where treatments for preventing complications after venous thromboembolism [are] not reaching everyone in the same fashion,” he told TCTMD. “And so we do need to find other ways to address the racial and socioeconomic disparities or inequities here.”

The findings were published simultaneously online in Circulation: Cardiovascular Quality and Outcomes.

Big Increase in DOAC Use

Use of DOACs—both for stroke prevention in A-fib and for the treatment and prevention of VTE—has grown dramatically over the past decade, and Nathan et al wanted to see whether there have been any inequities in terms of adoption—in this case, for patients with VTE.

Using OptumInsight’s Clinformatics Data Mart, which contains administrative claims from commercially insured Americans, the investigators looked at data on 14,140 patients who had an incident diagnosis of VTE between 2010 and 2016, and a first filled prescription for an oral anticoagulant within 30 days of discharge. The analysis excluded patients with other indications for oral anticoagulation.

Overall, 74.2% of patients received a vitamin K antagonist, with the rest receiving a DOAC. However, the rate of DOAC use increased over time from just 0.1% in 2010 to 65.6% in 2016.

Both race/ethnicity and socioeconomics were found to influence uptake. After adjustment for potential confounders, black patients were less likely than their white counterparts to be prescribed a DOAC (OR 0.86; 95% CI 0.77-0.97), consistent with a prior study in patients with A-fib. Such a difference was not seen for Asian or Hispanic patients.

In addition, having an annual household income > $100,000 versus < $40,000 was associated with a greater likelihood of being prescribed a DOAC (OR 1.50; 95% CI 1.33-1.69).

‘We Have Work to Do’

Both Nathan and Hernandez said it’s likely that a combination of factors explain the observed disparities.

Nathan pointed out that prior studies have shown that black patients may have reduced access to specialty care and that there are differences in health insurance coverage across demographic groups. Also, he said, implicit bias could be playing a role.

As Nathan and his colleagues explain in the paper, “Studies suggest many healthcare providers demonstrate signs of implicit bias, with positive attitudes towards white patients and negative attitudes towards patients of color. The presence of implicit bias among providers may contribute to the reduced likelihood of DOAC therapy in black patients with VTE, as they may preferentially prescribe novel, more expensive therapeutics to white patients due to perceptions of higher socioeconomic status and ability to afford the medication.

“In addition,” they continue, “it has been previously demonstrated that provider interactions with patients of color are less patient-centered, with fewer requests for patient input about treatment decisions in general.”

In addition to implicit bias, Hernandez cited issues involving access, environment, and health literacy as being possibly involved in the inequities seen in the study.

“Do [patients] have access to the right coverage for using these therapies? Are they in the healthcare environments that can routinely understand and implement these new therapies and new evidence more quickly?” he said. In addition, for certain groups of patients, “there may not be as much awareness in terms of choices they have for improving their health or preventing future health problems.”

Hernandez said the medical community has to make sure that no patient groups are being left behind when new medical products are introduced.

“We shouldn’t be a number of years out and then find out that we missed the boat, like in this case,” he said. “As new things come up, we should be much more proactive and measure it quickly, and ensure the trajectories are similar across different groups.”

This study, Hernandez said, “highlights that we have work to do in terms of closing the gap for inequities.”