New Risk Calculator for Cardiovascular Disease Could Leave Millions Ineligible for Medication

The researchers predict an additional 107,000 heart attacks and strokes over the next 10 years.

Statins, hailed as a wonder drug upon their introduction 35 years ago, have revealed a long list of unexpected side effects as the decades have passed.roger ashford/Shutterstock

A new calculator for assessing cardiovascular risks like heart attack and stroke may make nearly 16 million people ineligible for blood pressure and cholesterol medications.

According to a new study published in the Journal of the American Medical Association, the risk calculator is better calibrated and more precise than previous versions, but if current treatment guidelines for cholesterol and blood pressure therapy don’t change with it, the calculator could have unintended consequences, according to research from Harvard Medical School.

In November 2023, the American Heart Association (AHA) released a new risk calculator called “predicting risk of cardiovascular disease events” (PREVENT), which was developed as a result of population changes and shifts in cardiovascular disease trends over the past two decades. It now provides 10-year risk estimates for 30-to-70-year-old patients and 30-year estimates for 30-t-59-year-old patients.

Like the previous tool, PREVENT uses standard cardiovascular measures, like cholesterol and high blood pressure, but includes new factors, like kidney function, blood sugar, and urine protein. These metrics of kidney disease were included because Type 2 diabetes and kidney disease are known to coexist with cardiovascular disease and obesity. The updated calculator also excluded race as a factor.

Although the AHA unveiled the calculator, the organization has not yet endorsed it, nor has the American College of Cardiology. However, according to a press release, that hasn’t stopped some clinicians from using it to guide patient care.

Potential Clinical Effects of the New Calculator

The Harvard Medical School analysis noted that the differences in recommendations between the calculator and current treatment standards could make 15.8 million people ineligible for treatment.

The researchers based their projections on a cross-sectional sample of over 7,700 participants between the ages of 30 and 79 from the National Health and Nutrition Examination Survey (NHANES). They compared the previous 2013 calculator against the 2023 PREVENT calculator to determine risk and outcomes for cardiovascular disease events.

The analysis showed that the PREVENT risk calculator would reclassify nearly half of the U.S. population into lower-risk categories, and less than 0.5 percent would be reclassified into higher-risk categories. More than 14 million people would no longer qualify for statins, and 2.6 million would no longer qualify for blood pressure medications.

Men between 50 and 69 would be most affected by the change, and black men more so than white. Using the PREVENT calculator, according to the researchers, could mean an additional 107,000 heart attacks and strokes over the next 10 years.

“The takeaway from our study is that updating risk estimation without reconsidering treatment thresholds has the potential to change recommended care for millions of Americans,” Dr. James Diao, the study’s first author, said in the press release.

Weighing the Risks

Estimating an individual’s 10-year risk for having a heart attack or stroke is a key part of preventing cardiovascular disease among healthy individuals and ensuring it doesn’t recur in patients with a history of cardiac events. However, estimations must be highly individualized to control a disease that claims more lives than any other in the United States.

The authors expressed concern about how this new calculator may affect those previously eligible for statins and other medications.

“I would be concerned if we only change one side of this equation without reexamining the other side, which is the treatment threshold,” senior author Raj Manrai said in the press release.

The researchers noted that under the new risk calculator, fewer statin prescriptions could mean 57,000 fewer new-onset diabetes cases, as statins are linked to a heightened risk of diabetes. However, lack of treatment may put those newly ineligible at greater risk of cardiovascular events.

Ultimately, the researchers said that the decision to treat is up to the patient and the doctor and must go beyond a risk calculator.

“The sort of nuanced decision-making that needs to occur at the physician’s office means that after a careful conversation, two people with the same estimated level of risk might end up on different treatment regimens,” Manrai said. “And that’s a good thing.”