New heart attack risk calculator appears flawed

A new online tool that is supposed to help doctors calculate a patient's risk of heart attack has been experiencing problems.Leading heart organizations in the United States recently released a new set of guidelines intended to clarify rules on reducing cholesterol. However, one of the key components of that effort – an online heart attack risk calculator – has been suffering through some early glitches, hampering the rollout of what physicians and researchers had hoped would be a new, more effective way to prevent heart attacks.1

New guidelines delayed?

The new guidelines had already been somewhat controversial, with several experts and cardiovascular health organizations questioning the methods of the group that issued the rules. And the problems with the calculator, which appears to routinely overestimate the risk of future heart attacks in patients, only served to magnify those concerns.

The calculator uses several factors to determine a patient’s risk of a heart attack over the ensuing decade, with a potentiality of 7.5 percent or more being considered the threshold for the prescription of cholesterol-reducing statin medication.

But after several physicians ran test cases through the calculator, they found that it resulted in diagnoses of heightened risk for a substantial group of patients who would not normally be considered in the danger zone. That overestimation could lead to thousands of patients being prescribed medication they don’t need.

“Since the risk calculator was not previously published, it now makes sense to halt implementation of the guidelines so that independent physician scientists can evaluate the accuracy of the risk calculator,” Dr. Steven Nissen, chief of cardiovascular medicine at the Cleveland Clinic, told CNN in an email.2 “We have waited many years for these guidelines. It seems prudent to wait a little longer to make certain that the guidelines function as intended.”

Defending the calculator

The groups that developed both the guidelines and the calculator responded to the concerns quickly, saying that, while flawed, they represented an improvement in the way heart attack risk is treated.

Speaking specifically to the calculator’s glitches, spokespeople for the groups pointed out that it was not meant to be the sole factor in determining whether to prescribe statins. Instead, it is intended to be one of many considerations that physicians and patients look at when deciding on a course of treatment.

Impact on health professionals

When treating patients, the risk of heart attacks is always one of the foremost considerations for physicians, certified medical assistants and pharmacy technicians. And having accurate guidelines and tools to figure out risk is imperative. The hope is that as these new rules are assessed it will lead to a better understanding of the risks, and allow medical professionals to be more accurate in their prescriptions.

1 Kolata, Gina, “Risk Calculator for Cholesterol Appears Flawed,” The New York Times, Nov. 17, 2013. http://www.nytimes.com/2013/11/18/health/risk-calculator-for-cholesterol-appears-flawed.html?_r=0
2 Hayes, Ashley, “Does Calculator Overstate Heart Attack Risk?” CNN.com, Nov. 18, 2013. http://www.cnn.com/2013/11/18/health/cholesterol-calculator/

Join the conversation