Millions of Americans have a blood test every year to measure LDL, often called “bad” cholesterol. But new research from Northwestern Medicine suggests that another test may do a better job of identifying who needs more aggressive treatment to reduce the risk of heart attacks and strokes.
The study, published in JAMA, found that measuring apolipoprotein B (apoB) was more effective than tracking LDL or non HDL cholesterol when deciding whether to intensify cholesterol lowering therapy, including statins and other medications.
“We found that apoB testing to intensify cholesterol-lowering medication would prevent more heart attacks and strokes than current practice, and that these health benefits were achieved at a cost that represents good value for U.S. healthcare payers,” said study lead author Ciaran Kohli-Lynch, assistant professor of preventive medicine in the division of epidemiology at Northwestern University Feinberg School of Medicine.
Kohli-Lynch said this is the first comprehensive analysis to show that using apoB to guide cholesterol treatment is also cost effective.
Heart disease remains the leading cause of death in the United States and is responsible for enormous healthcare spending. Over time, tiny cholesterol carrying particles can become trapped inside artery walls, where they build up into plaques that restrict blood flow and raise the risk of heart attacks and strokes.
Why ApoB May Be a Better Measure of Heart Disease Risk
Doctors have long relied on LDL cholesterol and non HDL cholesterol levels to decide when patients should begin or intensify cholesterol lowering treatment. While those tests provide useful information, they do not fully capture a person’s cardiovascular risk.
“Research strongly shows that apolipoprotein B (apoB) is better at identifying who is at risk, because it counts the total number of harmful particles in the blood,” explained Kohli-Lynch.
Unlike standard cholesterol tests, apoB measures the number of cholesterol carrying particles that can contribute to plaque buildup. Researchers say that makes it a more direct indicator of cardiovascular risk.
Even with growing evidence supporting apoB, the test is still not commonly used in routine care. Kohli-Lynch said one reason is that measuring apoB generally requires an additional blood test beyond the standard cholesterol panel, increasing both cost and inconvenience.
“Our study asked: Is it worth spending extra money to use apoB instead of LDL to guide treatment intensification?” Kohli-Lynch said.
Computer Model Compared Three Cholesterol Testing Strategies
To answer that question, the research team created a computer simulation representing 250,000 U.S. adults who were eligible for statin therapy but did not already have cardiovascular disease.
The model compared three approaches for guiding treatment:
LDL cholesterol (goal <100 mg/dL)
Non-HDL cholesterol (goal <118 mg/dL)
ApoB (goal <78.7 mg/dL)
When patients failed to meet their target, treatment was stepped up first by using stronger statins and then by adding ezetimibe if needed.
Researchers followed each strategy over a lifetime, estimating heart attacks, strokes, life expectancy, quality of life, and healthcare costs.
The results showed that using apoB to guide treatment consistently performed better than the LDL and non HDL approaches. It improved overall health outcomes, prevented more cardiovascular events, and did so in a way the researchers determined was cost effective.
New Cholesterol Guidelines Increase the Importance of Accurate Testing
The findings come as doctors have more cholesterol lowering medications available than ever before. Earlier this year, the American Heart Association and 10 other medical organizations also released updated guidelines recommending that many people begin cholesterol lowering therapy at younger ages.
“This means it is increasingly important to accurately identify who would benefit most from intensive treatment,” Kohli-Lynch said.
Other Northwestern coauthors include Drs. John Wikins and Samuel Luebbe.
The study, titled “Cost-Effectiveness of ApoB, Non-HDL-C, and LDL-C Goals for Primary Prevention Lipid-Lowering Therapy,” was supported by the American Heart Association Career Development Award 24CDA1274989 (Dr. Kohli-Lynch).
