Cholesterol Screening, Coronary Calcium, and Statins: A Practical Guide

This article is for general education only and not personal medical advice. Decisions should always be made with your own physician, using your specific history and risk profile.

Most heart attacks don’t really come “out of nowhere.” They develop over years of cholesterol-driven plaque quietly building up in the arteries.

The good news! we have clear, evidence-based guidance from the American Heart Association (AHA) and American College of Cardiology (ACC) on who should be screened, which tests add value, and when to start treatment. (AHA Journals)

In this article, I’ll walk through:

1. Who should be screened for cholesterol and how often

2. Which blood and imaging tests are worth considering, and when

TLDR

Atherosclerosis continues to be a top health concern. Early screening and aggressive treatment can vastly reduce your risk of heart attack and stroke. Make sure to talk with your physician about optimizing your risk.

Who should be screened?

Routine lab screening: AHA/ACC framework

A standard fasting (or non-fasting) lipid panel typically includes:

• Total cholesterol

• LDL (“bad”) cholesterol

• HDL (“good”) cholesterol

• Triglycerides

• Non-HDL cholesterol (total minus HDL), which bundles all atherogenic particles
  

The 2018 AHA/ACC/Multi-Society Cholesterol Guideline and the 2019 ACC/AHA Primary Prevention Guideline recommend: 

• Adults 20–39 years

Periodic cholesterol screening, especially if there are risk factors (family history of premature ASCVD, hypertension, diabetes, smoking, obesity, inflammatory conditions).

• Adults 40–75 years

Cholesterol testing plus 10-year ASCVD risk calculation using the ACC/AHA Pooled Cohort Equation, for adults 40–79.

Treatment decisions are based on LDL levels, overall 10-year risk, and “risk enhancers” (family history, metabolic syndrome, CKD, inflammatory diseases, elevated Lp(a), etc.).

• Adults >75 years

More individualized decisions. AHA/ACC guidelines emphasize weighing potential benefit versus polypharmacy, frailty, and life expectancy.

Red flags for earlier / more frequent screening

Independent of age, I consider earlier or more aggressive screening if there is:

• Strong family history of early heart attack or stroke (men <55, women <65)

• Known or suspected familial hypercholesterolemia

• Diabetes, chronic kidney disease, inflammatory/autoimmune disease, HIV

• Smoking, uncontrolled hypertension, metabolic syndrome

• History of preeclampsia or pregnancy-related hypertension

Advanced labs: ApoB and Lp(a) in the guideline era

ApoB (Apolipoprotein B)

ApoB reflects the number of atherogenic particles (LDL, VLDL, remnants). The AHA/ACC guidelines list elevated ApoB as a risk-enhancing factor, particularly in the setting of high triglycerides or metabolic syndrome (think smaller beta coefficient in the regression – important but less than LDL).

Lp(a) – Lipoprotein(a)

Lp(a) is largely genetic and independently raises cardiovascular risk. Approximately 20% of the population has elevated levels. The AHA supports at least once-in-a-lifetime testing in adults. There are no current specific treatments for elevated Lp(a) currently but several treatments in clinical trials.

Imaging: guided by AHA/ACC recommendations

Coronary artery calcium (CAC) scanning

What it is
A low-dose, non-contrast CT that quantifies calcified plaque in the coronary arteries and generates a CAC score.

Where it fits in AHA/ACC guidelines

The 2018 Cholesterol Guideline and 2019 Primary Prevention Guideline give a Class IIa recommendation (“reasonable to do”) for CAC scoring in adults at borderline (5–7.4%) or intermediate (7.5–19.9%) 10-year ASCVD risk when the decision about statin therapy is uncertain. 

In practice:

• CAC = 0

  AHA/ACC guidelines note that a CAC of 0 can justify deferring or delaying statin therapy in some borderline or intermediate-risk adults.

  CAC > 0 (or >100)

Suggests some coronary plaque; guidelines favor statin therapy.

Pros

• Non-invasive, no contrast

• Modest radiation (often comparable to a mammogram, ~0.2-2 mSv)

• Provides a concrete number that can personalize and motivate treatment

Tradeoffs

• Out-of-pocket cost in many systems

• Some radiation exposure

• Does not visualize non-calcified/”soft” plaque

• Adds less value in clearly low-risk or clearly high-risk patients (where decisions are already clear)
  

In a prevention-focused practice, CAC is especially useful for:

• Adults 40–70 with borderline/intermediate 10-year risk

• Patients reluctant about starting statins

• People with strong family history but equivocal standard risk calculators
  

Other imaging (and why it’s usually not first-line for screening)

Under AHA/ACC guidance, the main imaging tool for asymptomatic risk refinement is CAC. Other modalities are more situational:

CT coronary angiography (CCTA) – higher radiation (~1.5 to 3 mSv and contrast; reserved for patients with symptoms or higher suspicion of obstructive disease. It can identify “soft plaque” not seen on CAC which is more common in certain ethnic groups.

Stress testing – meant to detect flow-limiting blockages, not overall plaque burden; not recommended as a screening tool in asymptomatic adults.

In part 2, I’ll discuss treatment options and why you shouldn’t wait!