Using risk-adjusted percent time in therapeutic range (TTR) can help anticoagulation control and improve patient outcomes, according to a study published in the Jan. 3 issue of Circulation: Cardiovascular Quality and Outcomes.
“While warfarin is effective, it is difficult to thin a patient's blood enough to protect them while avoiding dangerous over-anticoagulation,” the authors wrote. Excessive anticoagulation can result in a fatal bleeding event, and inadequate anticoagulation can lead to adverse events, like stroke.
To better understand the factors surrounding anticoagulation control, Adam Rose, MD, of the Boston University School of Medicine (BUSM) and Bedford VA Medical Center in Bedford, Mass., and colleagues profiled 100 VA sites using risk-adjusted TTR to understand whether site-level performance is based on quality of care or patient population.
The researchers found that TTR varied among VA anticoagulation clinics—from 38 percent to 69 percent and from poor to excellent control. And while Rose and colleagues said that the risk-adjusted model did not alter performance rankings for most sites, for other sites it made “an important difference.”
For example, an anticoagulation clinic was ranked 27th out of 100 prior to the risk-adjustment but was ranked seventh after the risk-adjustment, the authors noted. “This demonstrates the importance of adjusting TTR for case mix when profiling performance,” the authors noted.
Lastly, the researchers found that site performance on risk-adjusted TTR was consistent from year to year, which suggests that risk-adjusted TTR measures quality of care that is stable, rather than using a statistical variation.
“Our study suggests that risk-adjusted TTR should be considered for more widespread use as a performance measure as part of an effort to improve anticoagulation control and thus improve patient outcomes,” said Rose.
"As a nation, we spend vast amounts of effort and resources profiling performance regarding diabetes, blood pressure, acute coronary syndromes, cancer screening and commonly performed surgeries," Rose concluded. "Until now, we have not tried to profile performance regarding anticoagulation control. This study suggests that we can—and we should."