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Ask a cardiologist: Family history

Q: Several people in my family had heart attacks in middle age. How can I prevent this happening to me?

A: It’s been well established since the 1950s that some families have an inherited predisposition to developing coronary artery disease (CAD) at a younger age than expected. CAD is the most common form of heart disease, when arteries in the heart are narrowed and blocked. It can lead to a heart attack.
A contemporary U.S. study involving more than 5,000 people across a range of ethnic groups found that participants with a family history of premature CAD were significantly more likely to show signs of CAD themselves.

If I were your cardiologist, I would be most interested in your first-degree relatives – your parents and siblings. I would be looking for cases of premature coronary artery disease; in a male relative, that’s younger than age 55 and for a female relative, it’s under 65. So if a close relative had a heart attack or stroke, required bypass surgery, or received angioplasty at an early age, that would be a red flag.

In general, inherited risk may also compound; if the genes are clustering in your family, you are likely to face a higher risk of heart disease. But a higher risk does not mean an accelerated risk. And risk does not mean an absolute likelihood either. There are several actions we can take to reduce your risk of having an event in spite of family history.

While assessing your family history, we would tease out any lifestyle factors such as smoking, which can amplify an inherited risk. I would incorporate all this information into one of the risk score tools that help us estimate your 10-year or 20-year risk of a major heart event. This assessment then guides us in making decisions about primary prevention — in other words, strategies or treatment to reduce the risk of developing overt coronary heart disease.

Ways to reduce risk

We always focus on lifestyle first, by counselling and trying to direct the patient toward making healthy choices. We review smoking, of course – avoiding tobacco is a no-brainer to reduce your risk. Other factors we’ll consider include blood pressure and cholesterol, which are again affected by your genes, but just as important are diet and exercise.

In many cases, exercise and diet changes are enough to reduce your risk, with the right support, commitment and time. If we think more aggressive action is required, depending on your risk, we might consider cholesterol medications such as statins and possibly Aspirin. Cholesterol is one of the main modifiable risk factors where intervention can help; there is robust research showing that if someone is at high enough risk, we should consider treatment.

With a high enough estimated risk, compounded by your family history, the tradeoff of benefits to side effects from medications tips toward the benefits.

Genetic research shows promise

One of the other most common familial predispositions to heart disease is high cholesterol that runs in some families, called familial hypercholesterolemia, or FH for short.

The good news is that through major advances in research, we’ve been able to isolate a genetic abnormality among some families with this condition. In studies about 10 years ago – identifying cohorts of patients who either had no coronary artery disease and very low cholesterol, or very high cholesterol and accelerated risk of CAD – researchers found a genetic defect that could be a drug target. Within a short time this discovery led to development of a potent new cholesterol lowering medication that appears effective in patients with FH and high cholesterol in general.

As a result of this work, now we have some new injectable anti-cholesterol medications called PCSK9 inhibitors, which should be approved in Canada soon. They seem to be quite beneficial, particularly for patients with FH, who can be sensitive to statins or just aren’t able to get their cholesterol into the normal range with statins alone.

So although it is never good when you’re told you may have inherited a genetic defect, we are privileged that today we can leverage the discoveries behind these family histories to find new treatments that may help folks with high cholesterol.

What everyone can do

You should be talking to your family about health issues – both current and in previous generations. If a grandparent died young, for example, it’s a good idea to find out why. If you come across red flags such as I’ve described above, talk to your doctor and perhaps ask for a referral to a cardiologist.

You’d be surprised when I ask about family health history how many times people say – “I never thought to ask that question.” Some people won’t know much because it was a different time when the family member had a health problem, or perhaps they don’t have that kind of relationship with their family, or they were adopted, or it’s been a while since they’ve asked about any health concerns.

But don’t worry – routine risk assessment by your doctor will still go a very long way to making healthy changes and reducing your risk as much as possible.

  • Do you have a question for our cardiologist? Send it to Unfortunately we cannot provide personal replies. Questions of general interest will be answered in future Heart and Stroke Foundation publications.

This article is for informational purposes only and is not a substitute for medical advice, a medical diagnosis or treatment from a physician or qualified healthcare professional. The Heart and Stroke Foundation of Canada assumes no responsibility or liability arising from any error in, or omission of, information, or from the use of any information or advice contained in this article.

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  1. Pingback : Demandez à un cardiologue : Étranges symptômes de maladies du cœur | Votre santé | FMCoeur Blogue

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