Understanding Lipoprotein(a) and Why Repeated Testing Matters
Share
Lipoprotein(a), often written as Lp(a), is a type of cholesterol particle in the blood. High levels of Lp(a) can increase the risk of heart disease and stroke. Most people have their Lp(a) level checked only once in their life because it is largely determined by genes and believed to stay stable over time. But recent studies, including the one we are discussing here, suggest the picture might be more complicated.
What Makes Lp(a) Levels Change
In theory, Lp(a) levels should not change much because they are mostly genetic. However, changes can happen for two main reasons
Biological changes can occur due to certain health conditions. For example, kidney disease, liver disease, thyroid problems, menopause, or severe inflammation can affect Lp(a) levels. Some medications, like statins, may also slightly change them
Technical changes happen when there are errors in how blood samples are taken, stored, or measured. Even using a different testing machine or method can cause differences in results.
Why This Study Was Different
This research focused on separating true biological changes from technical errors. The scientists studied 715 older adults and measured their Lp(a) levels twice, about three years apart. They used very strict testing methods: each sample was measured twice, and both tests for a person (from the first and second visit) were run side-by-side in the same lab session. This helped remove most technical errors.
What the Researchers Found
The results showed that for most people, Lp(a) levels stayed almost the same. Over 91 percent of participants stayed in the same “risk category” from the first to the second test. Only 8.4 percent moved to a higher or lower risk group, and big changes were rare.
When differences were seen, they were usually small. On average, the change was less than 1 mg/dL, which is not enough to make a big difference in lifetime heart disease risk for most people.
How Changes Affect Heart Disease Risk
The study also looked at how mistakes in measuring Lp(a) could change a person’s estimated lifetime risk for heart attack or stroke. They found that if the test underestimates your true Lp(a) by 5 mg/dL, your calculated lifetime risk might be off by about 1 percent. This is a small effect for most people. However, very large errors — for example, underestimating by 30 mg/dL — could change the risk estimate by 5 to 7 percent, which could affect treatment decisions.
When Should You Repeat an Lp(a) Test
For most people, repeating the test is not needed. But there are situations where it may be useful
-
If the first result is close to a treatment threshold
-
If you develop kidney disease, severe liver disease, or other conditions known to change Lp(a)
-
If there is a major unexpected change in your result, which could point to a technical error
-
If you are being considered for or are already on Lp(a)-lowering therapy
In these cases, a repeat test can help confirm whether the change is real.
Practical Takeaways for Patients
- Know your Lp(a): Ask your doctor if you have ever been tested. If not, one test in adulthood is usually enough.
- Don’t panic over small changes: Small differences in results are common and often not clinically important.
- Look at the big picture: Lp(a) is just one risk factor for heart disease. Your blood pressure, LDL cholesterol, lifestyle habits, and family history are also important.
- Repeat testing only when needed: Most people do not need frequent checks unless their medical situation changes.
Final Thoughts
This study reassures us that Lp(a) levels in healthy older adults are generally stable over time. Big changes are rare and often linked to technical issues rather than true biological shifts. While one lifetime measurement is still the rule for most, targeted repeat testing can be helpful in special situations. As testing technology improves, we may be able to detect real changes with even greater accuracy — helping doctors and patients make better-informed decisions about heart health.