High Cholesterol and Lipoprotein(a): Understanding Cardiovascular Risk and Treatment
Assoc. Prof. Sezen Bağlan Uzunget, MD
Cardiologist
What Is Cholesterol?
Cholesterol is a fat-like substance essential for cell membranes, hormone production, and bile acid synthesis.
The body produces cholesterol naturally, and some is obtained from food.
Although cholesterol is necessary for normal body function, excessive levels of certain cholesterol-carrying particles can contribute to atherosclerosis, the accumulation of plaques within artery walls.
Atherosclerosis increases the risk of heart attack, ischemic stroke, and peripheral artery disease.
What Are LDL, HDL, and Triglycerides?
LDL Cholesterol
Low-density lipoprotein (LDL) carries cholesterol through the bloodstream.
An excessive number of LDL particles promotes cholesterol accumulation within arterial walls.
LDL is a causal factor in the development of atherosclerotic cardiovascular disease.
Lowering LDL cholesterol reduces the risk of cardiovascular events.
HDL Cholesterol
High-density lipoprotein (HDL) participates in transporting cholesterol from peripheral tissues toward the liver.
Low HDL cholesterol is associated with increased cardiovascular risk.
However, medications that simply increase HDL cholesterol have not consistently demonstrated a reduction in cardiovascular events.
Triglycerides
Triglycerides are another type of circulating lipid.
Elevated triglyceride levels may be associated with metabolic dysfunction and increased cardiovascular risk.
Very high triglyceride concentrations can also increase the risk of acute pancreatitis.
Why Is High Cholesterol Dangerous?
Excess LDL cholesterol contributes to the development of atherosclerotic plaques.
These plaques may cause:
- Coronary artery disease
- Myocardial infarction
- Carotid artery disease
- Ischemic stroke
- Peripheral artery disease
Atherosclerosis may progress for many years without symptoms.
Feeling healthy does not necessarily mean that elevated cholesterol is harmless.
Does High Cholesterol Cause Symptoms?
Usually not.
High LDL cholesterol generally does not cause specific symptoms.
It is commonly detected through blood testing.
Certain inherited conditions with very high cholesterol levels may cause tendon xanthomas or other visible findings.
However, their absence does not exclude high cholesterol.
What Should My LDL Cholesterol Level Be?
LDL cholesterol targets depend on an individual's overall cardiovascular risk.
Commonly used European risk-based targets include:
- Cardiovascular risk | LDL cholesterol target |
|---|---|
| Low risk | Below 116 mg/dL |
| Moderate risk | Below 100 mg/dL |
| High risk | Below 70 mg/dL, with at least 50% reduction when indicated |
| Very high risk | Below 55 mg/dL and at least 50% reduction from baseline |
Risk assessment considers age, diabetes, kidney disease, previous cardiovascular events, imaging findings, and other factors.
Patients with established atherosclerotic cardiovascular disease generally require more intensive LDL lowering than those at low risk.
What Is Lipoprotein(a)?
Lipoprotein(a), or Lp(a), is a distinct lipoprotein particle structurally related to LDL.
It consists of an LDL-like particle attached to a protein called apolipoprotein(a).
Lp(a) is not simply free LDL cholesterol. It is a separate lipoprotein particle with additional biological properties.
Lp(a) concentrations are predominantly determined by genetics.
Diet, exercise, and weight changes generally have a limited effect on Lp(a) levels.
Why Is Lipoprotein(a) Important?
Elevated Lp(a) is associated with increased risk of:
- Coronary artery disease
- Myocardial infarction
- Ischemic stroke
- Peripheral artery disease
- Calcific aortic valve stenosis
Genetic and epidemiological evidence supports a causal contribution of elevated Lp(a) to atherosclerotic cardiovascular disease and calcific aortic valve disease.
High Lp(a) can increase cardiovascular risk even when LDL cholesterol is within the normal range.
How Is Lp(a) Different from LDL Cholesterol?
- Feature | LDL cholesterol | Lipoprotein(a) |
|---|---|---|
| Main determinants | Genetics and lifestyle | Predominantly genetics |
| Response to diet | May improve | Usually limited |
| Response to statins | Substantial reduction | Usually little or no reduction |
| Atherosclerotic risk | Increased | Increased |
| Association with calcific aortic stenosis | May contribute to overall risk | Strong genetic and epidemiological association |
| Measurement | Standard lipid testing | At least once in adulthood is recommended |
Who Should Have Lp(a) Measured?
Current European guidance supports measuring Lp(a) at least once during adulthood.
Testing is particularly useful in individuals with:
- Premature coronary artery disease
- A family history of early cardiovascular disease
- A family history of elevated Lp(a)
- Familial hypercholesterolemia
- Unexpectedly early atherosclerotic disease
- Cardiovascular events despite well-controlled LDL cholesterol
- Calcific aortic valve stenosis
Testing first-degree relatives may be appropriate when elevated Lp(a) is identified.
What Is Considered a High Lp(a) Level?
Lp(a) may be reported in:
- mg/dL
- nmol/L
Commonly used categories include:
- Lp(a) concentration | General interpretation |
|---|---|
| Below 30 mg/dL | Lower Lp(a)-related risk |
| 30–50 mg/dL | Intermediate range |
| 50 mg/dL or higher | Clinically important risk-enhancing level |
In the 2025 ESC/EAS focused update, an Lp(a) concentration above 50 mg/dL (approximately 105 nmol/L) is identified as a cardiovascular risk-enhancing factor.
There is no universally accurate conversion factor between mg/dL and nmol/L.
This is because apolipoprotein(a) particle size varies among individuals.
Cardiovascular risk increases progressively with increasing Lp(a), rather than appearing suddenly at one threshold.
Does High Lp(a) Matter If My LDL Is Low?
Yes.
Low LDL cholesterol is protective, but it may not completely eliminate the additional risk associated with high Lp(a).
More intensive LDL lowering and management of other risk factors may be appropriate, depending on the individual's overall risk.
Do Statins Lower Lipoprotein(a)?
Statins effectively lower LDL cholesterol and reduce cardiovascular events.
However, they generally do not lower Lp(a).
Some studies have reported small increases in Lp(a), while others have found little overall effect.
This does not mean statins should be avoided in patients with elevated Lp(a).
When statin treatment is indicated, LDL cholesterol reduction remains especially important.
How Is High Cholesterol Treated?
Treatment combines lifestyle measures and medication when appropriate.
1. Healthy Nutrition
Reducing saturated fat, avoiding trans fats, increasing dietary fiber, and following a Mediterranean-style eating pattern may improve LDL cholesterol levels.
2. Physical Activity
Regular exercise supports cardiovascular health and risk reduction.
3. Smoking Cessation
Avoiding tobacco is essential for reducing atherosclerotic risk.
4. Statins
Statins are a cornerstone of LDL-lowering therapy.
5. Ezetimibe
Ezetimibe reduces intestinal cholesterol absorption and provides additional LDL lowering.
6. PCSK9 Inhibitors
Selected PCSK9 inhibitors substantially lower LDL cholesterol and may also reduce Lp(a) by approximately 20–30%.
However, the proportion of their clinical benefit specifically attributable to Lp(a) reduction remains uncertain.
7. Other LDL-Lowering Treatments
Bempedoic acid and inclisiran may be considered in appropriate patients.
Treatment selection depends on cardiovascular risk, LDL concentration, coexisting conditions, and tolerability.
Are There Medications Specifically Targeting Lp(a)?
Several therapies designed to reduce Lp(a) production are being investigated, including:
- Pelacarsen
- Olpasiran
- Lepodisiran
- Other RNA-based therapies
Clinical studies have demonstrated substantial Lp(a) reductions with several investigational agents.
However, reductions in Lp(a) concentration must be distinguished from proven reductions in clinical outcomes such as heart attack and stroke.
The role of these treatments depends on the results of cardiovascular outcome trials and applicable regulatory approvals.
What Is Lipoprotein Apheresis?
Lipoprotein apheresis is a procedure that removes certain lipoproteins from the bloodstream.
It may be considered in carefully selected patients with markedly elevated Lp(a) and progressive cardiovascular disease, depending on national eligibility criteria.
It is not routinely recommended for everyone with elevated Lp(a).
Should Everyone with High Lp(a) Take Aspirin?
No.
Elevated Lp(a) alone is not a universal indication for aspirin.
Decisions about antiplatelet therapy should consider established cardiovascular disease, overall risk, and bleeding risk.
Does Carotid Plaque Mean Cholesterol Medication Is Necessary?
Carotid atherosclerotic plaque is an important finding in cardiovascular risk assessment.
However, treatment decisions should not depend solely on the size of a small plaque.
LDL cholesterol, plaque burden, diabetes, hypertension, smoking, family history, Lp(a), and other risk factors should be considered together.
Patients with established atherosclerotic disease often require intensive LDL-lowering treatment.
Small incidental plaques require individualized interpretation.
Must Cholesterol Medication Be Taken for Life?
The answer depends on the underlying condition and cardiovascular risk.
Long-term treatment is frequently necessary in patients with previous myocardial infarction, coronary stents, established atherosclerotic disease, or familial hypercholesterolemia.
A normal cholesterol result while taking medication does not necessarily mean the underlying risk has disappeared.
Medication should not be discontinued without medical advice.
Frequently Asked Questions
Can diet lower Lp(a)?
Usually not substantially. Nevertheless, healthy nutrition remains important for overall cardiovascular risk reduction.
Should Lp(a) be measured every year?
Usually not. Because levels are largely genetically determined, one measurement is sufficient for many adults. Repeat testing may be useful in selected circumstances.
Is high Lp(a) inherited?
Yes. Lp(a) concentrations are predominantly genetically determined.
Can a heart attack occur despite normal LDL cholesterol?
Yes. Cardiovascular risk also depends on Lp(a), smoking, diabetes, hypertension, and other factors.
Can high Lp(a) cause aortic valve stenosis?
Elevated Lp(a) has a causal association with calcific aortic valve stenosis, although not everyone with high Lp(a) develops valve disease.
This content is intended for general educational purposes. Cholesterol treatment and interpretation of Lp(a) results should be individualized according to cardiovascular risk, clinical history, and current medical evidence.