University researchers have developed a new model to help individuals at risk of stroke select the best preventative drug — based in part on cost effectiveness.
The model, co-authored by Dr. Geoff Barnes, a clinical lecturer of cardiovascular medicine and vascular medicine, and Deborah Levine, an associate professor of internal medicine, focused on drugs for one type of irregular heartbeat — nonvalvular atrial fibrillation — which can lead to strokes.
This irregular heartbeat happens when disruptive electrical activity triggers unusual contractions of the heart’s main pumping chambers, called the ventricles. When the ventricles are triggered, the heart doesn’t pump blood through the body as efficiently, which can cause clotting. These clots, in turn, make their way to vessels in the brain, potentially forming blockages that lead to strokes.
Currently, two classes of drugs are available to treat the condition — a cheaper anticoagulant known as a warfarin, which has been around for decades, and a new, more expensive line known as dabigatran.
Barnes said the two treatment options have left many Americans with irregular heartbeats facing a difficult economic choice.
Beyond the drugs themselves, he noted the issue has also been challenging because prescription prices vary depending on health care coverage. Barnes said this makes a cost-conscious model especially important. Their model is unique, he said, because it also considers the patient’s perspective on cost, as opposed to prior studies that only considered cost from a societal or insurance perspective.
“The importance of this decision comes from a patient’s perspective, as we discuss with them the affordability of these decisions based on their personal situations,” he said.
Along with patient perspective, the model draws on several other factors — how well the drugs prevent stroke, the possibilities of side effects and the cost of the pills — to determine the advantage and disadvantages of each.
Overall, Barnes and Levine said the team found that the prescription drug coverage a patient has matters most in terms of cost and benefits. Those without coverage, according to the study, could pay thousands of dollars for more effective drugs such as dabigatran, which may not always be worthwhile.
Barnes said many patients in that category are those who receive coverage through Medicare Part D. Under Medicare Part D, throughout much of the year, patients’ prescription costs are covered; however, at a set point, patients’ prescription coverage is exhausted and they must pay out of pocket.
“For the first part of the year, our patients have good coverage,” Barnes said. “By the late fall, when faced with the ‘donut hole,’ many patients will pay thousands of dollars per pill … unfortunately, patients will try to stretch out their prescriptions, not taking them every day, skipping doses.”
However, the study found that patients with prescription drug coverage, including Medicare Part D, had overall costs savings when choosing the more expensive dabigatran over warfarin.
This was primarily because of the effectiveness both drugs have on stroke, and also because they eliminated the need for more frequent blood draws and visits to the clinic that users of warfarin sometimes require.
However, Levine said she thought many of the patients facing issues with Medicare Plan D will see some changes moving forward due to recent changes in federal health care policy.
“Under the Affordable Care Act, this coverage gap known as the ‘donut hole’ will slowly be closed by 2020,” she said.
In terms of how a physician might use the model, Levine said she hoped clinicians would consider criteria for selecting a drug beyond going only physical well-being, and include metrics for cost and patient affinity.
“Certainly, we have to weigh the patient’s values and preferences when making these decisions about which drugs to choose,” she said.