If your father had a heart attack at age 55, does that mean you are destined to have one, too?
“No, it doesn’t mean that,” says UCI Health cardiologist Dr. Shaista Malik, medical director of the UCI Health Preventive Cardiology & Cholesterol Management Program.
“A family history of premature heart disease is a significant risk factor. But, just like other risk factors such as high blood pressure, high blood sugar or cholesterol, it can be controlled with lifestyle changes.”
Heart attack risk factor study
A recent study published in The New England Journal of Medicine sheds new light on this topic. It looked at how both genetic and lifestyle factors contribute to one’s risk of coronary artery disease. This is telling because coronary artery disease is the nation’s leading cause of death.
The study was groundbreaking because it pooled 50 known genetic markers of heart disease risk. Previously, doctors knew there was no single predictive gene, but studying multiple genetic markers hadn’t been done. The study also considered the four healthy lifestyle factors advocated by the American Heart Association:
The study found that those with a high genetic risk for heart disease almost doubled their risk for a cardiovascular event (heart attack or stroke).
The good news is that these individuals lowered their risk by nearly half (46 percent) by having a healthy lifestyle, which in this case means adhering to at least three of the four healthy lifestyle factors listed above.
Those with less genetic risk for heart disease similarly cut their overall heart-disease risk by leading a healthy lifestyle.
Heart disease genetic screening
“Our understanding of genetics is rapidly changing,” notes Malik, who is also director of the Susan Samueli Integrative Health Institute. “There’s not just one factor. There are multiple genes at work.”
She predicts that up to 200 genetic markers will be identified in the next three to five years to better test for genetic predisposition to heart disease.
A simple DNA test would then be able to give you a score classifying your genetic risk for heart disease: low, moderate or high. This screening could be done for cancers and other conditions, too.
Malik is leading a separate five-year study of cardiovascular genetic risk and coronary calcium, thanks to a $3.2 million grant from the National Institutes of Health. Her research is seeking to answer such important questions as what percentage of high-genetic-risk individuals actually end up having cardiovascular events such as heart attacks or strokes.
So what’s her take on hereditary versus lifestyle factors?
“There is a saying that genes load the gun, but environment pulls the trigger,” says Malik. “We are all predisposed to different illnesses. These genes can lay dormant or be activated by environment, which includes lifestyle, stress and even infections. Lifestyle can have a dramatic effect on what we used to think was our genetic destiny.”
How to lower your risk
If you’re aware of a family history of heart disease or have two or more of the four American Heart Association lifestyle factors, such as obesity and smoking, see your physician or a cardiologist.
It’s always best to get your situation checked out before symptoms occur.
A family history of heart disease is generally defined by having a first-degree male relative (i.e., father or brother) who had a heart attack by age 55, or a first-degree female relative (i.e., mother or sister) by age 65.
Just as important, consider lifestyle changes that improve your heart health.
“You can see changes in your risk over a short period of months,” says Malik.
It’s familiar advice, to be sure, but all can reduce your risk of a heart attack and possible premature death.