April 19, 2019 by John Fernandez
Who Benefits from a ‘Polypill’? Research Points to CT Scans for Answers
While scientists work to develop a single pill that will reduce the overall risk of heart attacks and heart disease, research led by senior investigator Khurram Nasir, M.D., MPH, director of wellness and prevention research at Baptist Health Medical Group, indicates only people with calcium in their arteries may benefit from the so-called “polypill.” That research is being published today in the Journal of the American College of Cardiology (JACC).
The “polypill” combines three or more medications, such as aspirin, blood thinners and blood pressure medicines, into one pill. Some experts believe giving this treatment to everyone over the age of 50 or to people with specific risk factors for heart disease would significantly reduce the overall number of heart attacks and cardiovascular deaths in this population over the long run.
Other experts are concerned that giving the polypill to an entire population will expose a lot of people, who are unlikely to develop heart disease, to potential side effects. They also warn this would unnecessarily increase the overall costs of heart disease prevention.
Dr. Nasir and his fellow researchers found that using a CT scan to reveal the amount of calcium in a person’s coronary arteries can identify people who are most and least likely to benefit from polypill treatment ahead of time.
“Although the concept of combining well-proven medications in a single pill for ease of use is an attractive option, it comes with the risk of over-treating a lot of individuals who may not benefit or need these medications,” Dr. Nasir said.
The scan gives doctors a simple number – a Coronary Artery Calcium (CAC) score – that places people in low, moderate, or high-risk groups before they develop any symptoms. The CAC score corresponds to whether someone is likely to develop heart disease.
For the research published today in JACC, Dr. Nasir and lead author Márcio Sommer Bittencourt, M.D., from Brigham and Women’s Hospital, show that the CAC score is a good indicator of those who may benefit from taking the polypill. They looked at thousands of patients in their Multi-Ethnic Study of Atherosclerosis (MESA) study and separated out those patients who would qualify to take the polypill, based on their age and risk factors for developing heart disease.
Of those in the MESA study who would qualify to take the polypill, only those with CAC scores greater than 100 had experienced a heart attack or other cardiovascular event 7.5 years into the study. People with a CAC score between 1 and 100 had moderate risk. Those with a CAC score of 0, showing no evidence of plaque in their arteries, theoretically could safely defer polypill treatment, the researchers found.
“The most important finding of our study is that it shows the majority of individuals who may meet criteria for these medications have no atherosclerosis, or plaque buildup, in the arteries of the heart; have a less than one-in-1,000 chance per year of having a heart attack; and may not benefit from the polypill,” Dr. Nasir said.
But, he says, giving this potentially effective prevention treatment to the 15-20 percent of people who experience the majority of heart attacks makes more sense.
He adds that this more targeted approach will be more cost effective as well. “These [CT] scans cost approximately $75 to $100, and the research suggests only 20 high-risk individuals with moderate calcium scores would need to be scanned and treated over five years to prevent one adverse cardiovascular event,” he said.
In an accompanying editorial in JACC, William Wijns, M.D., Ph.D. and Dan Rusinaru, M.D., Ph.D. of the Cardiovascular Research Centre Aalst in Belgium, acknowledged the study’s significance. “The results of this analysis are of great interest,” they wrote. They describe use of the CAC score to guide treatment as an “innovative approach” but raise some concerns, including the limited availability of the scanning technology in emerging countries and the amount of radiation exposure from the scan, which they describe as low but still greater than a chest X-ray.
Dr. Nasir and his colleagues describe the amount of radiation as low – equivalent to the amount of radiation delivered by a mammogram to both breasts.
Because coronary artery disease can develop over time, further research is needed to show how often patients with lower risk need to return for re-evaluation, Dr. Nasir says.
And while researchers debate these findings, it’s important to note the polypill is not yet available to patients. Clinical trials are underway to determine whether the combination of these proven medications into one pill is effective overall.
“While this research is exciting to the medical community and has the potential to change the way we manage heart disease in the future, we don’t want people to think they should stop taking their medication,” he said. “Dr. Nasir’s research will help us figure out down the road which of our patients may benefit from combined medications in a single pill and who we may recommend less intensive therapy, such as lifestyle changes and regular check ups, to manage their risks.”