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Healthful Lifestyle Could Offset Genetics and Add Years
of CVD-Free Living

People who follow seven rules for healthy living—such as staying physically active and eating a healthful diet—could offset a high genetic risk of heart disease, according to new research suggesting this could mean as many as 20 extra years of life free of heart disease.

The study, published in the American Heart Association (AHA) journal Circulation, found people with high cumulative genetic risk scores for heart disease could dramatically lower that risk if they adhered to seven lifestyle modifications, called Life’s Simple 7. In addition to eating a heart-healthy diet and moving more, this includes not smoking, maintaining an appropriate weight, and keeping blood glucose, cholesterol, and blood pressure levels well managed.

The findings aren’t the first to suggest lifestyle can give a person with high genetic risk a winning edge against heart disease, but they’re the first to use a new genetic risk tool to show how much disease-free living a person might gain by taking steps to reduce that risk, says lead study author Natalie Hasbani, MPH, a doctoral candidate and graduate research assistant at the University of Texas Health Science Center at Houston.

“It’s important to communicate these risks in a way that’s truly impactful,” she says, “to put it in terms of what the information can do for me.” Translating risk reduction into an absolute measure—years lived free of disease—is something more typically done in cancer treatment research, she says. “The hope is that hearing these numbers can convince people to change their behaviors.”

This was the first study to use the tool to predict lifetime risk of heart disease and the number of years both Black and white adults might live free of it if they adhered to a set of healthful lifestyle guidelines.

Polygenic risk scores are a relatively new tool that includes all of a person’s genetic information rather than individual genes associated with a disease. The scoring is based on the total number of variants that increase heart disease risk found in a person’s genetic code, in accordance with studies that compare the genes of people who have the disease with those who don’t.

The study calculated heart disease risk for 8,372 white adults and 2,314 Black adults aged 45 and older. Overall, it found the risk of developing heart disease during a person’s remaining lifetime ranged from 16.6% for those who practiced the most healthful lifestyles to 43.1% for those with the least healthful lifestyles. People with high polygenic risk scores could lower their risk of heart disease by up to 50% by also scoring high on adherence to the healthful lifestyle recommendations, compared with their high–genetic risk peers who didn’t follow the recommendations.

The impact of a healthful lifestyle varied by race. For white adults at high genetic risk, living an ideal lifestyle offered 20.2 more years of heart disease–free living compared with those with the least healthful lifestyles. But Black adults at high risk of heart disease were able to gain only 4.5 disease-free years by living a healthful lifestyle.

However, polygenic risk scoring relies on data culled largely from people of European descent. That means it’s less reliable when used to predict risk of Black adults and others of non-European descent whose DNA isn’t well represented in the data pool, the researchers say.

“We need larger genetic association studies in Black adults if we’re going to do better in summarizing their risk,” says the study’s senior author Paul de Vries, PhD, an assistant professor at the School of Public Health of the University of Texas Health Science Center at Houston.

In a 2021 scientific statement, the AHA called for greater inclusion of people from diverse ethnicities and ancestry in medical research to create more accurate tools for identifying genetic risk of disease in these groups. Efforts are now underway to collect those data, says Donald Lloyd-Jones, MD, ScM, FAHA, the AHA’s president and chair of the department of preventive medicine at Northwestern University Feinberg School of Medicine in Chicago.

In the meantime, “applying (polygenic risk scores) to someone who’s African American or Asian just doesn’t work very well,” he cautions. “It has the potential to create real problems with health disparities until we get better data.”

Polygenic risk scores may be most useful when used to identify people younger than 40 who carry a high genetic risk of heart disease and don’t know it, Lloyd-Jones says. Decisions about whether someone should take medications such as statins to reduce heart disease risk currently are based on whether they’re likely to develop heart disease within 10 years, which isn’t typically the case for someone in their 30s but might be for someone with high genetic risk.

“We could be missing opportunities to start treatment earlier when it might have a bigger impact,” he says. “But there’s not a lot of value in genetic risk scores to date for older people. Once people reach middle age, their personal health behaviors tend to matter a lot more than whatever genes they were born with.”

The main message of this study, Lloyd-Jones says, is that “while family history or genetics are important, they don’t determine your fate. If you are at high risk, you can lower it by pursuing a healthy lifestyle. Likewise, if you’re at lower risk, you can worsen your situation by not controlling behaviors.”