You may have been told time and time again that to avoid heart disease, making healthy lifestyle choices are key—from eating well, exercising regularly, avoiding cigarettes and managing your weight. But exactly how much time do these changes buy us?
New research – published in January in the American Heart Association journal Circulation – found healthy living and lifestyle modifications could secure as much as 20 extra years of life, free of heart disease.
Researchers discovered people with high cumulative polygenic risk scores (a method used to learn about someone’s risk of developing a disease) for heart disease could significantly reduce their risk if they followed seven lifestyle changes, known as Life’s Simple 7 (LS7): physical activity, eating a healthy diet, refraining from smoking, losing weight, and maintaining appropriate blood pressure, cholesterol and blood sugar levels.
Natalie Hasbani, MPH, lead author of the study and research assistant at UTHealth School of Public Health, told Seasons that while other research already explores how these lifestyle changes can lower the risk of heart disease, this study is the first to use a genetic risk tool. Using such a method shows how much someone could live heart disease-free if they implement lifestyle changes.
“The purpose of this and the hope is by telling people a little bit more in concrete, absolute risk terms what could happen if they make those changes,” Hasbani said. “It’s pretty impactful when you read something that says, I have a really high genetic susceptibility for something, but I can change that risk by 20 years.”
Understanding the study
Researchers analyzed data from participants of the Atherosclerosis Risk in Communities study and calculated heart disease risk for 8,372 white adults and 2,314 black adults, all aged 45 and older, using polygenic risk scores.
According to Hasbani, polygenic risk scores are a tool that includes all of a person’s genetic information, rather than individual genes connected with a disease. The scoring is calculated based on the total number of variants found in a person’s genetic code that increase heart disease risk, while using studies that compare the genes of people who have the disease with those who don’t.
“We’re taking your genetic information or summarizing it into a single risk score, very similar to any other risk factors,” she said. “We’re just doing that at the genetic level and creating something that can tell you whether or not you’re at high or low risk.”
The researchers concluded the risk of developing heart disease during a person’s remaining lifetime ranged from 16.6% for individuals who practiced Life’s Simple 7 to 43.1% for individuals with a poor practice of LS7.
Hasbani adds people with high polygenic risk scores could still lower their risk of heart disease by up to 50% if they strictly follow healthy lifestyle recommendations compared to those who don’t follow them.
“A higher score means that you just potentially have a higher grouping of genes that might be putting you at risk without being super specific about what those genes are,” she said. “But the good news is just because you have a high polygenic score, that doesn’t mean you are predestined to have coronary artery disease.”
How race plays a role
Hasbani notes the study was the first to use polygenic risk scores as a tool to predict lifetime risk for heart disease and the impacts on both black and white adults.
Researchers found white adults with high polygenic risk scores that followed healthy lifestyle factors from LS7 gained 20.2 more years of heart disease-free living compared to those with poor lifestyle habits. However, black adults – with high polygenic risk scores for heart disease – were only able to gain 4.5 years more of disease-free living by following healthy habits.
However, polygenic risk scores have largely relied on data from populations of European ancestry and descent, Hasbani said, so when using this data, it’s less reliable to predict the risk for black adults and others who have a different genetic makeup.
Last July, American Heart Association officials called for more inclusion of people from different ethnicities, ancestries and races in genomic research.
Yet, while the data only included white and black adults, Hasbani said, in general, following healthy lifestyle behaviors or Life’s Simple 7 could have benefits despite racial or ethnic make-up.
“We can still estimate across all populations how lifestyle influences you regardless of genetic risk,” she said. “You can get almost 10 years of your life back if you have an ideal lifestyle versus an intermediate or poor lifestyle, and that applies pretty much across the board to everybody.”
Inherited risk factors also play a role
If a particular disease runs in the family, you may have inherited factors that can put you at risk for developing that disease as well, according to the Genetic Science Learning Center at the University of Utah.
Coronary artery disease is a chronic disease that has one of the strongest heritabilities, Hasbani said.
“Family history plays a very strong role in coronary heart disease,” she said, “and is one of the number one predictors that we look at from a clinical standpoint to say, you probably have an inherited component to this disease.”
However, she said polygenic risk factors are emerging and in a way replace some of that information acquired from family history because it includes data and details at the genetic level.
What we can learn from the study
While family history, genetics and intersecting identities like race and culture play significant roles in heart disease risk, Hasbani believes implementing healthy lifestyle behaviors is also key.
“My hope is to give people a peace of mind, and that if you are at high risk for something, it’s not the end all be all,” she said. “My hope is that people can look at this number and be a little more motivated to change what they’ve been doing.”