Millions of Americans get a blood test each year to measure LDL, often called “bad” cholesterol. But new research from Northwestern Medicine suggests that another test may better identify who needs more aggressive treatment to reduce the risk of heart attacks and strokes.
The study, published in JAMThey found that measuring apolipoprotein B (apoB) was more effective than tracking LDL or non-HDL cholesterol in deciding whether to intensify cholesterol-lowering therapy, including statins and other medications.
“We found that apoB testing to intensify cholesterol-lowering medications 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 the study’s senior author, Ciaran Kohli-Lynch, an 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, small cholesterol-carrying particles can become trapped inside the walls of your arteries, where they build up, forming plaques that restrict blood flow and increase the risk of heart attacks and strokes.
Why ApoB may be a better measure of heart disease risk
Doctors have long relied on LDL and non-HDL cholesterol levels to decide when patients should start or intensify cholesterol-lowering treatment. While such tests provide useful information, they do not fully capture a person’s cardiovascular risk.
“Research clearly 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,” Kohli-Lynch explained.
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 typically requires an additional blood test to the standard cholesterol panel, adding to 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.
A computer model compared three cholesterol testing strategies
To answer that question, the research team created a computer simulation representing 250,000 American adults who were eligible for statin therapy but did not yet have cardiovascular disease.
The model compared three approaches to guide treatment:
- LDL cholesterol (target
- Non-HDL cholesterol (target
- ApoB (target
When patients failed to reach their goal, treatment was intensified by first using stronger statins and then adding ezetimibe if necessary.
The researchers followed each strategy throughout life, estimating heart attacks, strokes, life expectancy, quality of life, and health care costs.
The results showed that using apoB to guide treatment performed consistently better than LDL and non-HDL approaches. It improved overall health outcomes, prevented more cardiovascular events, and did so in a way that researchers determined was cost-effective.
New Cholesterol Guidelines Increase Importance of Accurate Testing
The findings come as doctors have more cholesterol-lowering drugs available than ever before. Earlier this year, the American Heart Association and 10 other medical organizations also released updated guidelines recommending that many people start 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 co-authors include Drs. John Wikins and Samuel Luebbe.
The study, titled “Cost-effectiveness of ApoB, non-HDL-C, and LDL-C targets for lipid-lowering therapy in primary prevention,” was supported by American Heart Association Career Development Award 24CDA1274989 (Dr. Kohli-Lynch).