Can a DNA test predict a person's future heart health? Perhaps, researchers say.
A team of Canadian researchers found that by analysing a person's entire genome, it might be possible to predict their future heart disease risk.
The so-called "polygenic risk score" analysis looks for key heart disease indicators – genetic "biomarkers" – along with an individual's entire genetic blueprint, or genome.
Prior research had already suggested that this type of analysis could determine heart attack risk for people of European descent with no prior heart attack history. But the new analysis suggests the approach can work just as well in other populations.
As lead researcher Guillaume Lettre explained, the polygenic risk score "is like having a snapshot of the whole genetic variation found in one's DNA, and [it] can more powerfully predict one's disease risk. Using the score, we can better understand whether someone is at higher or lower risk to develop a heart problem."
Lettre is an associate professor at the Montreal Heart Institute and the University of Montreal.
One US heart expert agreed that an accurate means of pinpointing heart risk is sorely needed.
Too often "the first symptom of a heart attack is the heart attack [itself]," said Dr Guy Mintz, who directs cardiovascular health at the Sandra Atlas Bass Heart Hospital in Manhasset, New York.
Using tools such as the polygenic risk score, patients at risk could be spotted sooner so that "we can apply more intense improvement in their personal cardiac risk factors at an earlier age", he reasoned.
"I would welcome using this type of precision medicine, individualised medicine, to identify children and adolescents as well as adults" at high risk for heart disease, Mintz said.
In the new analysis, Lettre's group compiled polygenic risk scores for more than 3 600 French Canadian heart disease patients. They then compared those results to those from nearly 7 400 who were heart disease-free.
The result: polygenic risk scores were just as predictively useful for French Canadians as they were for people from other genetic backgrounds, with an ability to accurately pinpoint about 6% to 7% of those tested as having a high risk for heart disease.
One caveat: The analysis was not as useful for those who had already experienced a heart attack. That might be because people with prior attacks tended to be older, and most were already taking drugs, such as statins, to lower their cardiovascular risk, the team theorised.
A sobering thought
Dr Eugenia Gianos directs women's heart health at Lenox Hill Hospital in New York City. Reviewing the findings, she said the new test "held up quite well for its predictive ability for the presence of coronary artery disease".
If the test pans out, it "could innovate how we tailor medical therapies to those at greatest risk earlier in life," she believes.
And Mintz noted that many people live with heart disease for years without knowing it.
"A sobering thought is that heart disease, [arterial] plaque, has been found at autopsy in teenagers and young adults," he said. "So, knowing early on who needs more intense surveillance and therapy could be a game-changer," Mintz explained.
"While the polygenic risk score is less accurate in predicting second heart attacks, I am not worried about that population, because we do a good job in treating this group," he said.
Lettre and his colleagues published their findings in the journal Circulation: Genomic and Precision Medicine.
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