Coronary artery disease (CAD) is a condition in which there’s a buildup of plaque (cholesterol deposits) in the arteries that supply blood to your heart. This buildup can lead to reduced blood flow and, in some cases, a heart attack or stroke. CAD is more likely to develop in people over 60 years old with a family history of the disease.

According to the Centers for Disease Control (CDC), CAD is the most common type of heart disease. It’s sometimes called coronary heart disease or ischemic heart disease.

Both lifestyle and genetics contribute to CAD. Smoking and obesity can increase your risk, and so might your genes.

Read on to learn how your family history affects your disease risk and what you can do about it.

Coronary artery disease by the numbers

According to the CDC:

  • More than 360,000 people died due to CAD in the United States in 2019.
  • About 18.2 million adults, or about 6.7 percent, ages 20 years and older have CAD.
  • Adults under 65 years old account for about 2 in 10 deaths from CAD.

What you eat, how much you exercise, and whether you smoke are critical clues in assessing your risk for CAD. Other conditions such as obesity, hypertension, and hyperlipidemia (high cholesterol) are also indicators.

But recent research has also shown that genetics are important, too. CAD is estimated to be 40 to 60 percent heritable. People with a family history are about 1.5 times more likely to develop CAD than those without a family history.

So what’s a family history? Doctors consider you to have a family history if premature heart disease is present in first-degree relatives before age 55 in men or 65 in women. A first-degree relative is a parent, sibling, or child.

Family history is a powerful predictor of CAD. About one-third of patients with CAD have a first-degree relative with the disease.

But family-based studies on CAD have their limits. It can be challenging to separate shared lifestyle factors in families from genetic factors you can pass down. For example, people in the same family may have similar diets or habits that contribute to coronary artery disease, independent of their genetics.

Thanks to large-scale genetic sequencing, scientists can now identify gene variants common in people with CAD. As of 2017, researchers had found about 60 specific gene variants that may be related to your risk of developing CAD. According to a 2021 review, that number has since grown to over 200.

These variants play a role in controlling your blood pressure and processing lipids (fats) in your blood, such as cholesterol. A 2016 review of studies suggests that the cumulative effect of several of these gene variants is what causes an increased risk of CAD.

It’s important to understand that these genes don’t mean that you definitely will develop CAD. They just mean that your risk may be higher. Whether you develop CAD will also depend on lifestyle factors.

Early genetic research on CAD focused almost exclusively on European and North American populations, where most data were available. In recent years, researchers have been able to gain a more global picture of the genetics of CAD. Variants responsible for CAD may vary by ethnicity, but there is not enough research to draw any conclusions.

CAD health disparities do exist among racial and ethnic groups.

A 2015 review of studies found that CAD disproportionately affects some races and ethnicities. In the United States, prevalence was highest among people identified as African American, Hispanic, Native American or Alaskan Native. It was lower among people identified as white, Asian, or Pacific Islander.

According to a 2020 study, this may be due to disparities in access to quality medical care.

More research is needed to fully understand how genetics and ethnicity interact to affect CAD risk.

In addition to having a first-degree relative with CAD, several factors can put you at risk for the disease. These include:

  • being a postmenopausal woman
  • being a man over 45 years old
  • high blood pressure
  • high cholesterol
  • smoking
  • being overweight or having obesity
  • having diabetes

Will I have coronary artery disease if my parents have it?

Genetics do not define your health outcome, but they’re a good reason to assess your lifestyle and risk factors.

Just because a parent has CAD does not mean you’ll have it. However, if one or both parents (or other first-degree relatives) has premature CAD, your chances of developing the condition are higher.

It’s best to discuss your health history with a healthcare professional so they’re aware of it. They can give you advice about how you can prevent developing CAD yourself. They may also prescribe preventive medication.

How likely am I to pass CAD down to my children?

It’s not a foregone conclusion that you will pass down CAD. That said, research indicates that CAD is 40 to 60 percent heritable, so there is a possibility of passing down the disease. This is especially true if you or your partner have or develop premature CAD.

How can I prevent coronary artery disease if it runs in my family?

Living a lifestyle with health-promoting benefits can help prevent, reduce the chance of (mitigate), or delay the onset of serious diseases, including heart disease. Positive lifestyle choices include:

A healthcare professional may recommend genetic testing if you have a first-degree relative with premature CAD and you have high cholesterol, or in other circumstances that increase your risk.

It’s best to let your healthcare team know about your family history of CAD as soon as possible. They can better assess your risk and help you take action if needed.

Can genetic testing reveal coronary artery disease?

Genetic testing can help you assess your likelihood of developing CAD, but it cannot help make a diagnosis. Your healthcare team will perform several tests before making a diagnosis.

Genetic testing can help identify people at risk for heart disease who would be good candidates for statin therapy. Statins are medications that help regulate your cholesterol, reducing your risk of plaque buildup in your arteries.

Coronary artery disease can be life threatening, so it’s important to know your risk of developing it. It’s more common in people over 60 years old and those with a first-degree relative with premature CAD.

If you have a family history of CAD, your healthcare team may recommend genetic testing to assess your risk of developing it. Testing can also help you and your team determine if you need medication to lower your risk of a heart attack.

CAD is heritable, so family history can be a strong indicator that you may develop it. If you or your partner has or develops premature CAD, it’s more likely that your children may develop the disease.

It’s important to see a healthcare professional and discuss your family history and concerns. Together, you can determine an appropriate prevention or treatment plan.