Your Heart Health: What Family History Tells You

It is good that you are actively thinking about what steps you can take to prevent history from repeating itself. Although cardiovascular disease (CVD)—the number one killer and a leading cause of premature, permanent disability in the US—may be more common in families with a positive family history of CVD, the outlook is far from hopeless.

Scientists have established that several risk factors—both modifiable (such as diet, physical activity level, and tobacco use) and nonmodifiable (such as age and genetics)—play a role in the development of CVD. Moreover, scientists are not even sure if the increased risk of developing CVD in someone with a family history of the disease is solely a result of a shared genetic predisposition or if it simply represents a greater exposure to the same harmful environmental influences.

Genetics and Cardiovascular Risk

The Human Genome Project was completed in 2003. The project was a scientific undertaking to identify all the genes in human DNA. It was done to assess specific genes to determine individual disease risk. Examples of genetic influences on cardiovascular risk that researchers studied included the following:

• Genes that appear to predispose a person to congenital heart disease (defects present at birth)
• Apolipoproteins B and E, which are proteins that combine with a lipid that affect blood cholesterol concentrations
• The angiotensinogen gene variant, an alteration in the hormone angiotensinogen, which is associated with high blood pressure
• Homocysteine, an amino acid which contributes to atherosclerosis by irritating vascular endothelial cells lining the blood vessels
• C-reactive protein, a protein that is a marker of inflammation and may predict future cardiovascular risk

However, while genetic and protein markers may identify enhanced CVD risk (and would allow for targeted prevention) further confirmation is required before widespread clinical use is appropriate.

What is known is that CVD occurs more commonly in families with a positive family history of the condition. This means that your risk of CVD is increased if any of your immediate relatives, such as siblings, parents, or children, have or had heart disease, a heart attack, or stroke, especially before age 50.

How Knowing Your Family History Can Help

Research clearly demonstrates that family history of CVD is an independent predictor of disease. One study looking at CVD in families in Utah found that while only 14% of families had a strong positive family history of coronary artery disease (CAD), these same people accounted for 72% of all CAD events, such as heart attack and coronary bypass surgery.

And, while only 11% of families had a positive family history of stroke, 86% of all early strokes occurred in these families. Since major cardiovascular risks (such as smoking and excessive alcohol consumption) may be less prevalent in Utah than in other states, these results may not apply throughout the country.

Nonetheless, because family members share not only the same positive family history, but also other modifiable risk factors, family history can help doctors capture the underlying complexities of both genetic and environmental influences leading to the appearance of disease.

Perhaps most important, people at risk for CVD because of their genetic makeup can benefit from modifying their behavior. For instance, quitting smoking is projected to decrease CAD to a greater extent in men with a positive family history of CAD compared to men without a positive family history.

Thus, family history is an important tool used by doctors to evaluate the risk of CVD.

What to Do If You Think You Might Be at Risk

In the future, as the genetic basis of CVD is unraveled, doctors may be able to diagnose disease based on tests for genetic markers.

In the meantime, while a family history of CVD does not doom you to the same fate, you are at a higher risk. Therefore, modifying certain risk factors for CVD, may help you reduce your risk of disease. These modifiable risk factors include the following:

• Quitting smoking—the single, most important risk factor that you can change
• Reducing the total fat, trans fat, and saturated fat in your diet
• Increasing fiber in your diet
• Controlling your blood pressure
• Controlling diabetes
• Exercising regularly—aim for at least 30 minutes per day on most days of the week
• Maintaining an ideal body weight
• Managing your stress
• Moderating your alcohol intake—1 or less drinks per day for women, 2 or less drinks per day for men
• Controlling cholesterol—lowering total cholesterol, LDL, and triglyceride levels while elevating HDL levels

Some doctors may also recommend taking aspirin daily or other medications. Talk to your doctor to find out if this is suitable for you.

Remember, prevention is key. Keep in mind, too, that if you have a family history of CVD, your children are at an increased risk as well. But you can set them on the right path to a healthful lifestyle. Children learn from example. So, if they see you eating right, not smoking, and getting plenty of exercise, they will be more likely to follow your lead.

Revision Information

• Reviewer: Michael Woods, MD, FAAP
• Review Date: 02/2017
• Update Date: 03/06/2015