New guidelines will recommend that approximately thirteen million more Americans use cholesterol-reducing drugs.

Issued by the American Heart Association, the new study was the product of a collaboration between researchers at Duke, Boston University and McGill University. The study examined previously available health data to determine the impact of the new guidelines, and found that the new guidelines would encourage nearly half the U.S. population between the ages of 40 and 75 to consider taking statins, which help lower cholesterol levels. This increase in the number of people who should take statins will occur because, for the first time, the guidelines will make recommendations based on an individual’s overall risk factors for heart disease instead of just their current cholesterol levels.

“When the new guidelines came out, many experts gave educated guesses about what the impact might be,” said Michael Pencina, the study’s lead author and director of biostatistics at the Duke Clinical Research Institute. “We don’t need to be guessing… we can actually quantify it and give a more scientific, a more realistic approximation.”

Pencina explained that the reason for the increased number of people recommended for statin therapy is a change in the way the guidelines look at risk. Previously, the guidelines advised people to take statins if their cholesterol levels were high. Under the new guidelines, recommendations are based on overall risk for heart disease.

Prior to the new guidelines, people with a 7.5 percent or greater chance of developing heart disease over the next 10 years are recommended to take statins.

“The new guidelines change the paradigm of treatment recommendations,” Pencina said.

The group that will see the largest increase in treatment recommendations is older men, according to the study. Under the old guidelines, 30.4 percent of men between the ages of 60 and 75 were recommended to take statins. The new guidelines recommend 87.4 use the therapy.

The new guidelines significant recommendations raise a need to further study whether statins are the best way to treat overall heart disease risk factors, not just high cholesterol, explained Dr. Eric Peterson, director of the DCRI and a co-author of the study.

“Whether it’s right, wrong or different is really not clear. There needs to be more trials in older individuals, particularly with those who have relatively normal [cholesterol levels],” Peterson said. “It seems reasonable that we might want to try to get better evidence about whether this works or not.”

Peterson also pointed out that because the new guidelines base recommendations on 10-year risk for heart disease, they may not be doing enough to help treat younger people who will be at risk further in the future.

Dr. Neil Stone, chair of the panel that wrote the new guidelines, explained that the guidelines point to other factors in addition to the 10-year risk which may indicate that a person should take statins.

“There are some people who don’t make the 7.5 percent [risk level] but have a family history of premature heart disease or an LDL [cholesterol level] above 160,” Stone said. “Clinicians, based on our guidelines, may want to treat them based on these special factors.”

About 500,000 cases of cardiovascular disease could be prevented by the new guidelines, said Dr. Ann Marie Navar-Boggan, a Duke Medicine cardiology fellow and co-author on the study. Navar-Boggan agreed that risks incurred from increased statin use are low and the benefits are high.

“While it’s true the new guidelines increase the total number of people recommended for statin therapy, I think a rigid application of the guidelines has the potential to do a lot of good in terms of decreasing the burden of cardiovascular disease going forward,” Navar-Boggan said.

Although statins do have side effects, they are already widely used and have value in preventing heart disease, according to the Food and Drug Administration.

Navar-Boggan also explained that the large number of people now being recommended to take statins can be attributed to the increase in heart disease and risk factors for heart disease.

“The fact that so many people are eligible for statin therapy really reflects the overall predicted burden of cardiovascular disease in the United States over the next 10 years,” she said.

This study on the AHA’s new statin guidelines is part of a broader research effort focusing on preventive medicine, led by Pencina.

“There’s been this group that’s trying to answer some of these fundamental questions about prevention and we’ve been collaborating for a period of time to do that,” Peterson said. “There’s a series of different other works we have in the pipeline that will address these questions.”

After an article on the study was published in the New England Journal of Medicine, the study’s results have been covered by major news organizations, including The New York Times, National Public Radio, CNN and USA Today.

Penicina said that he was pleased with the conversation which the coverage had started and hoped that the attention would fuel further research.

Navar-Boggan cautioned that there were some untrue claims that the study was funded by or linked to pharmaceutical companies circulating on social media.

“Our study was funded by independent research grants, not the pharmaceutical industry,” she said.