Millions may get wrong cholesterol test, study finds

A new comparison of three cholesterol testing strategies

Millions of Americans have blood drawn every year to measure LDL, the cholesterol fraction commonly labeled “bad,” and the result is used to decide who should start or intensify cholesterol-lowering therapy. A study published in JAMA and led by Northwestern Medicine researchers argues that a different test, one that measures apolipoprotein B (apoB), identifies more of the people who would benefit from treatment and does so at a cost the researchers describe as good value for U.S. healthcare payers.

Lead author Ciaran Kohli-Lynch, an assistant professor of preventive medicine in the division of epidemiology at Northwestern University Feinberg School of Medicine, said the analysis is the first comprehensive one to show that apoB-guided therapy is not just more effective but also cost effective. The Times of India reported the same finding, drawing on the ScienceDaily summary of the JAMA paper.

Why apoB may capture risk that standard tests miss

Standard lipid panels report LDL cholesterol and non-HDL cholesterol. Both express the amount of cholesterol circulating in the blood, but they do not directly count the number of particles carrying that cholesterol. Kohli-Lynch, quoted by ScienceDaily, said apoB is a stronger predictor because “it counts the total number of harmful particles in the blood,” the very particles that can lodge in artery walls and build into plaques.

The Times of India framed the same distinction by saying traditional tests “measure the amount of cholesterol, but apoB measures the vehicles carrying it.” Both outlets relied on the same Northwestern press material; the framing differs in emphasis but not in substance.

Heart disease remains the leading cause of death in the United States and a major driver of healthcare spending, according to the Northwestern summary. Even modest improvements in identifying high-risk patients can therefore translate into large numbers of prevented events at a population level.

How the researchers modeled the three strategies

To compare the testing approaches, the team built a computer simulation of 250,000 U.S. adults who were eligible for statin therapy but did not already have cardiovascular disease. Three treatment strategies were run in parallel, each with a defined target:

• LDL cholesterol, with a goal of less than 100 mg/dL.
• Non-HDL cholesterol, with a goal of less than 118 mg/dL.
• ApoB, with a goal of less than 78.7 mg/dL.

When a simulated patient did not meet their assigned target, treatment was stepped up first by switching to higher-intensity statins and then by adding ezetimibe if needed. The simulation followed each virtual patient over a lifetime, tracking heart attacks, strokes, life expectancy, quality-adjusted life years, and healthcare costs.

What the model found

Across those outcomes, the apoB strategy “consistently outperformed” the LDL and non-HDL approaches, according to ScienceDaily, preventing more cardiovascular events and improving overall health outcomes at a cost the researchers classified as cost effective. The Times of India reported the same conclusion, noting that the price point “represents excellent value for the U.S. healthcare system.”

Neither outlet provided absolute numbers for events prevented, life-years gained, or incremental cost-effectiveness ratios in the excerpts reviewed, so the precise magnitude of the projected benefit cannot be confirmed from the available material. The framing of “more events prevented” and “cost effective” is what the press materials and reporting actually state.

Why testing choices matter more now

The findings arrive as clinicians have more cholesterol-lowering medications available than at any previous point, and as the American Heart Association and ten other medical organizations have released updated guidelines recommending that many people begin cholesterol-lowering therapy at younger ages. Kohli-Lynch told ScienceDaily that this combination makes it “increasingly important to accurately identify who would benefit most from intensive treatment.”

The Times of India summarized the same dynamic, saying the new tools and rules represent a “shift in the way doctors treat people with heart problems,” particularly with the addition of newer cholesterol-lowering drugs. The two outlets agree on the underlying point: with more patients eligible for treatment, the test used to select them carries more weight.

Practical obstacles to broader apoB use

Despite the evidence cited in the JAMA paper, apoB is not part of routine lipid screening in most U.S. clinical settings. Kohli-Lynch told ScienceDaily that the main reason is logistical: “measuring apoB generally requires an additional blood test beyond the standard cholesterol panel, increasing both cost and inconvenience.” That is the practical question the study set out to answer: whether the extra cost of an additional test is justified by the health gains.

The Times of India echoed the same barrier, describing an extra draw and an extra charge. Neither outlet reported specific pricing for apoB testing in the United States or named major commercial laboratories that offer it on a routine basis. Whether insurers or large lab networks move to include apoB in standard panels will be a separate decision from the cost-effectiveness calculation.

Study details and funding

The paper is titled “Cost-Effectiveness of ApoB, Non-HDL-C, and LDL-C Goals for Primary Prevention Lipid-Lowering Therapy” and was supported by American Heart Association Career Development Award 24CDA1274989, held by Kohli-Lynch. Other Northwestern coauthors listed in the ScienceDaily summary are Drs. John Wilkins and Samuel Luebbe. The study was a modeling exercise rather than a randomized trial, which is a common approach for cost-effectiveness questions because it can project lifetime outcomes for large hypothetical populations.

How the two outlets differ

ScienceDaily and the Times of India wellness section drew on the same Northwestern press material and the underlying JAMA paper, so their core claims are aligned: apoB-guided therapy is projected to prevent more cardiovascular events than LDL- or non-HDL-guided therapy, and to be cost effective at a population level. The differences are editorial. ScienceDaily is more detailed on methodology, listing the specific mg/dL and mg/dL-equivalent targets, the stepwise intensification with statins and ezetimibe, and the funding award. The Times of India piece leans on analogy (“the vehicles carrying it”) and on broader context about the growing toolbox of cholesterol drugs and earlier treatment initiation.

The Times of India’s separate photostory on high cholesterol versus high blood pressure, also listed among the sources, provides background on how cholesterol differs from hypertension but is not directly connected to the Northwestern study; its inclusion here is for context only. Doctors quoted in that piece, including Dr. P. Ashok Kumar of KIMS Hospitals in Bengaluru, stress that high cholesterol and high blood pressure are mechanistically distinct but commonly co-occur, and that controlling both measurably reduces cardiovascular risk, a point consistent with the rationale for better risk stratification in the JAMA paper.

What is not in the sources

Several details a reader might expect cannot be confirmed from the supplied excerpts. The sources do not report the absolute number of heart attacks or strokes projected to be prevented, the incremental cost per quality-adjusted life year, the year of publication beyond “earlier this year” for the AHA guideline update, or statements from independent cardiologists not affiliated with Northwestern. The JAMA paper itself is referenced but not directly quoted beyond the title and authors listed by ScienceDaily. Any inference about real-world clinical uptake, insurance coverage, or changes to U.S. preventive care guidelines should be treated as outside what these sources verify.