A new study from researchers at the University of Birmingham in the United Kingdom has shown a treatment gap in certain patients with atrial fibrillation (AFib), a finding that concerns healthcare providers because the condition is associated with a five-fold increase in stroke risk.

The study, published in Heart, has revealed disparities in the way patients with different types of AFib are treated. Those with paroxysmal AFib are significantly less likely to receive anticoagulants that prevent stroke than those with persistent of permanent AFib, the study shows.

Researchers analyzed records of 14 million patients from nearly 650 surgeries that took place between 2000 and 2015. The data showed that though the proportion of AFib patient prescribed anticoagulants increased, paroxysmal AFib patients were prescribed fewer in 2015, which resulted in a treatment gap of 13 percent.

The findings are problematic because more patients are at risk for having a stroke that could have been prevented.

“While the anticoagulant treatment gap has narrowed over the years, from 15 percent in 2000 to 13 percent in 2015, over the same period a diagnosis of paroxysmal AFib became three times more common,” said study author Nicola Adderley, PhD, a research fellow at the university, in a statement. "This means that the number of paroxysmal AFib patients missing out on anticoagulants is greater now than 16 years ago. Paroxysmal AFib patients should be given the same priority for stroke prevention as other AFib patients.”