A new genetic test might help doctors identify individuals facing an increased risk of heart attacks "long before they have them," Gina Kolata writes for the New York Times.

A new genetic test may predict heart disease risk

A new genetic test, known as a polygenic risk score, analyzes thousands of genetic variants to assess heart disease risk. While each genetic variant may only partially contribute to risk, evidence suggests that the variants combined might indicate which patients are likely to have heart attacks.

"Cardiologists hope to use such tests, which cost about $150 and are not typically covered by health insurance, to identify people most likely to have heart attacks long before they have them," Kolata writes. "Some doctors envision testing children as part of routine pediatric care."

Individuals identified as high risk would receive aggressive treatment. Meanwhile, patients who are identified as low risk may be spared from unnecessary treatment.

"There's a real unmet need to identify high-risk people very early in life," said Nicholas Marston, a cardiologist at Brigham and Women's Hospital who has studied polygenic risk scores and been involved in trials for pharmaceutical companies that make cholesterol medicines. "We know the solution to preventing heart disease is getting your bad cholesterol as low as possible for as long as possible."

Currently, guidelines largely reserve cholesterol-lowering statin treatments for individuals ages 40 and older. However, "high cholesterol levels damage blood vessels slowly, over a period of decades," Kolata notes. A polygenic risk score may help doctors determine which patients have a high enough risk for early intervention.

Sadiya Sana Khan of Northwestern University underscored the need for more research. In her new study, she found that CT scans of the heart were better predictors of risk in middle-aged to older adults. "But that leaves a question about how to manage risk in young people, who almost never have visible plaque on a CT scan, even if they are at greater danger for a heart attack later in life," Kolata writes.

"We need more studies that focus on younger people with follow-up over several decades," Khan said.

In particular, Khan questioned whether young adults identified as high risk will be more likely to have a heart attack later in life or if they will simply be "needlessly worried about their hearts," Kolata writes.

Ultimately, experts believe polygenic risk scores are likely here to stay. Researchers at Geisinger are creating strategies for introducing them, including clinical trial planning.

"I predict it will be part of routine care," said Christa Martin, Geisinger's chief scientific officer. "We will treat it no differently than cholesterol screening or screening for diabetes." (Kolata, New York Times, 5/30)

2 health equity challenges for precision medicine

By Regina Lohr and Rachael Peroutky 

New genetic and genomic tests regularly enter the market with a promise to improve care — but should we use them? Typically, the only factor considered when answering that question is "does the test work?"

But that's often a grey area — and not just because of sparse clinical evidence. Even when there seems to be clear clinical evidence, inequities in healthcare may prevent providers from seeing the full picture of whether a certain test is right for their patient.

Inaccurate risk scores could further widen health disparities 

One serious flaw with genetic tests, including polygenic risk scores, is that they typically rely on non-diverse gene databases. The lack of representation is especially concerning for cardiovascular genetic tests as a person's race can impact their lifetime risk. For this reason, the test clinicians currently use to drive treatment decisions includes race as a factor.

Supplementing or replacing this existing clinical test with genetic tests may lead to under- or over-estimating risk scores for underrepresented communities — leading to even greater health disparities.

Affordability may limit access for some patients

Affordability is another challenge at play. Healthcare innovations tend to increase costs for all patients, but only some actually stand to benefit.

While the prices of genetic tests are falling, the total cost for patients who want to receive these tests can be much higher. For example, genetic testing may require a visit with a specialist, a trip to an out-of-network lab, and an appointment with a genetic counselor. For those with robust insurance coverage or the ability to pay out of pocket, this might be worth it. For others, it won't even be an option.

Still, in many cases, genetic tests demonstrate a net benefit and fulfill the promise of precision medicine to support diagnosis and treatment decisions. As innovation continues, providers from all specialties will have to consider the benefits and risks of genetic tests. We don't have all the answers yet, but we do know that we can never leave health equity out of the equation.  

The Advisory Board is currently developing a framework to help healthcare leaders weigh the risks and benefits of genetic and genomic tests. Stay tuned for more insights over the summer and join us for a deep dive into these questions at our Clinical Innovation Summit held August 22 and 23 in Minneapolis, where we'll discuss how to think about affordability and access differently to ensure that all patients are able to take advantage of important evolutions in care. (Fatumo et al., Nature Medicine, 2/2022)