We are going to talk about genetic testing for heart disease risk. Is it a good idea? Should you get genetic testing for heart disease, and could it save your life?
Genetic testing for heart disease risk has been a hot topic for many years. It’s exciting to think that we could determine someone’s risk for heart disease from a simple blood or saliva test. And knowing the amount of risk someone has for heart disease is important because risk it is the primary factor used in deciding the aggressiveness of your prevention strategy. For example, those who are at high risk, benefit the most from prevention treatments, like statin medications. Those who are at a low risk, on the other hand, won’t get much benefit from statins.
The problem is, we don’t have tools to help us accurately assess risk.
The most common way we assess risk is to add up some of the risk factors for heart disease, like high blood pressure, cholesterol, smoking, diabetes, and age. And we usually put these into a risk calculator, the most common being the ASCVD risk score. However, there are several other risk calculators.
Adding up risk factors works well in a population or big group of people, but it doesn’t always work so well in individuals because there is a lot of variation between us. Genetic testing, if effective, would be very attractive because it would allow us to be more accurate in our risk predictions and determine your individual risk rather than just the average risk of people like you.
It is estimated that about 40-50% of the risk for heart disease is genetic or inherited. The rest being environmental and lifestyle choice. So it makes sense that genetic testing would be valuable in helping to determine your risk for future heart disease. However, just because it makes logical sense doesn’t mean it helps. We have to demonstrate in a research study that genetic testing is better than our current way of assessing risk.
But does genetic testing add additional value over traditional risk factors?
Two large studies were published in JAMA that answered the question, does genetic testing add additional value over traditional risk factors. And the answer, in both studies, was no. Genetic testing did NOT do a better job of identifying those people who are at higher risk for heart disease than the old school way of adding up the usual risk factors.
These results are disappointing. Having a simple test that could help us learn who is at higher risk for heart disease and stroke would be valuable. But as it stands now, the current models of genetic testing for heart disease, don’t make a big enough difference to justify their use in most cases.
So what does work?
What does work when the risk for heart disease is unclear, the most common example of that is when one has a family history of heart disease, in my opinion, is imaging for artery disease with either a CT calcium score or a carotid ultrasound. Not everyone needs these tests, but if you and your doctor are unsure if you are at higher risk, they can help decide how aggressive to be with your heart disease prevention strategy.
As of today, genetic testing for heart disease risk does not seem to be helpful. But we are learning new things every day, and it will be exciting to watch how genetic testing evolves to help us lead healthier lives hopefully.