A new Northwestern Medicine study suggests a rarely used cholesterol test, apoB, could better guide treatment and prevent more heart attacks and strokes than today’s standard tests. Researchers also found the approach offers good value for the U.S. health care system.
A cholesterol test that most Americans have never heard of could help prevent more heart attacks and strokes than the standard blood work doctors order today, according to new research from Northwestern Medicine.
The study, published April 8 in JAMA, found that a blood test called apolipoprotein B, or apoB, outperformed traditional measures of low-density lipoprotein (LDL) and non-HDL cholesterol when used to guide cholesterol-lowering treatment such as statins.
The analysis shows that shifting to apoB-based care could save lives and money, according to lead author Ciaran Kohli-Lynch, an assistant professor of preventive medicine in the division of epidemiology at Northwestern University Feinberg School of Medicine.
“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,” Kohli-Lynch said in a news release.
For decades, doctors have relied on LDL, often called “bad cholesterol,” and non-HDL cholesterol levels to decide when to start or increase cholesterol medications. These tests measure how much cholesterol is circulating in the blood, but they do not directly count the particles that carry cholesterol and can lodge in artery walls.
Those particles, when they get stuck in arteries, can form plaques that build up over time and eventually block blood flow, leading to heart attacks and strokes. Heart disease remains the leading cause of death in the United States and a major driver of health care spending.
ApoB offers a different lens on risk. Each cholesterol-carrying particle that can contribute to plaque has one apoB protein, so measuring apoB effectively counts the total number of potentially harmful particles in the blood.
“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,” Kohli-Lynch added.
Despite that evidence, apoB testing is rarely used in routine care. It is not part of the standard cholesterol panel, and ordering it typically means an extra test, which can add cost and complexity to a clinic visit. That has raised a key question for doctors, patients and insurers: Is the added effort and expense worth it?
“Our study asked: Is it worth spending extra money to use apoB instead of LDL to guide treatment intensification?” added Kohli-Lynch.
To explore that question, the Northwestern team built a large computer simulation model representing 250,000 U.S. adults who were eligible for statins but did not yet have cardiovascular disease. The model allowed the researchers to compare, over a simulated lifetime, how different testing strategies would affect health outcomes and costs.
They examined three approaches to guiding treatment:
– Using LDL cholesterol with a goal of less than 100 milligrams per deciliter
– Using non-HDL cholesterol with a goal of less than 118 milligrams per deciliter
– Using apoB with a goal of less than 78.7 milligrams per deciliter
In each strategy, if a patient did not meet the assigned goal, treatment was stepped up. Doctors in the model first intensified therapy by prescribing stronger statins, then added another cholesterol-lowering drug, ezetimibe, if needed.
The simulation tracked heart attacks, strokes, life expectancy, quality of life and health care costs for each strategy over time.
ApoB-guided care came out ahead. According to the study, using apoB targets to decide when to intensify treatment improved population health and saved more lives than relying on LDL or non-HDL goals alone, while still being cost-effective for the U.S. health care system.
The findings arrive at a moment when cholesterol management is becoming more complex. Over the past decade, the number of available cholesterol-lowering medications has grown, giving doctors more tools but also more decisions to make about who should receive aggressive treatment and when.
At the same time, the American Heart Association and 10 other medical organizations issued new cholesterol guidelines earlier this year that recommend starting cholesterol-lowering therapy at younger ages for many patients who are at risk.
“This means it is increasingly important to accurately identify who would benefit most from intensive treatment,” Kohli-Lynch added.
By more precisely flagging people whose arteries are loaded with harmful particles, apoB testing could help clinicians focus powerful therapies on those who stand to gain the most, while sparing others from unnecessary medication.
The study did not change clinical guidelines on its own, but it adds economic evidence to a growing scientific case for apoB. Previous research has linked higher apoB levels to greater cardiovascular risk, even when LDL appears normal. The new work suggests that building apoB into routine decision-making could be a smart investment for health systems.
For patients, the research underscores that the familiar cholesterol numbers on a lab report may not tell the whole story. In the future, a more detailed look at the particles behind those numbers could become part of standard care, especially for people at higher risk of heart disease.
What happens next will depend on how quickly professional societies, insurers and clinicians respond to the new evidence. If apoB testing becomes more widely adopted, a once obscure lab value could play a central role in preventing some of the nation’s most common and deadly cardiovascular events.
Source: Northwestern University