Introduction

Cholesterol is a naturally occurring substance that is found in every cell of the human body. It plays an important role in the production of hormones, vitamin D, and bile acids that help with digestion. However, too much Cholesterol in the blood can lead to health problems including heart disease and stroke. In this article, we will explore a subtype of cholesterol that is often overlooked, which is non-HDL cholesterol. If the non-HDL cholesterol is higher than the optimal range, it can lead to adverse effects and decrease the quality of human life. We will discuss in-depth what is it, what is the normal range, how is it calculated, the risks associated with high cholesterol levels, and ways to maintain healthy levels through lifestyle changes and medical treatment.

What is Non-HDL cholesterol?

The progression of cardiovascular illnesses is significantly influenced by cholesterol levels. An increased risk of developing atherosclerotic cardiovascular disease (CVD) is associated with an elevated level of lipids, especially cholesterol and triglycerides in the serum (hyperlipidemia). In the medical field, getting a lipid profile helps with disease screening, diagnosis, and treatment. A lipid panel or lipid profile consists of lipoproteins (particles made of fats and proteins) like total cholesterol, High-density lipoprotein (HDL) or good cholesterol, low-density lipoprotein (LDL) or bad cholesterol, triglycerides, VLDL, and chylomicrons. Non-HDL cholesterol is the sum of all cholesterol present in all lipoproteins like VLDL (very low-density lipoproteins), and chylomicrons.^1,2.

How is this test done?

• To measure the level of non-HDL cholesterol in your body, your doctor will recommend a lipid panel test. This measurement requires a blood sample; your doctor will recommend a fasting or non-fasting lipid test.
• If your doctor recommends a non-fasting lipid test it can be done anytime during the day and does not require fasting.
• On the other hand, if your doctor recommends you a fasting lipid test, it will require you to fast for about 12 hours or as instructed by your doctor. 
• This test is done by using a blood sample; a needle will be used to withdraw blood from a vein in either of your hands.^2,3,4,5.

Risks associated with the tests: Withdrawing blood samples may cause a little pain and make you feel lightheaded, which will subside after a few minutes. In case of bleeding, bruising or rashes at the injection site contact your healthcare professional.

What might affect test results: The test results may be affected by what you eat, the medicines that you take, smoking, alcohol consumption, and exercise. Before going for a test, you should inform your healthcare professional about your diet, medicines, drinking, and smoking habits.

Test results: The test results may vary depending on your gender, age, history, and laboratory. Your healthcare physician will explain to you what the test results mean and whether any treatment is required in case of abnormal results.

Other tests needed: If your healthcare physician suspects heart disease, he may also recommend the following tests along with a non-HDL cholesterol test.

• Electrocardiogram (ECG)
• Stress test
• Echocardiogram
• Cardiac catheterization  

Non-HDL cholesterol range^2,3

As recommended by the National cholesterol education program (NCEP III), the adult treatment panel III, recommends that the range of non-HDL cholesterol should be higher by approx 30mg/dL as compared to LDL-cholesterol. For example, if the level of LDL-cholesterol is

Calculation of Non-HDL cholesterol

The level of non-HDL cholesterol is calculated by using the following equation:

Non-HDL cholesterol (mg/dl) = TC-HDL-C

Wherein TC is total cholesterol and HDL-C is high-density lipoprotein cholesterol.²

Importance of Non-HDL cholesterol

The use of non-HDL cholesterol in clinical practice is not a new concept. A review by Baker et al. in 2010 stated that non-HDL cholesterol may help in predicting cardiovascular diseases both in the general population and in people with diabetes.⁴ 

Non-HDL cholesterol is not usually a part of the lipid panel screening, but if you have diabetes, high blood pressure, or other risk factors the chances of having a heart attack become higher than normal. In such situations, your healthcare professional may calculate non-HDL cholesterol by using the equation discussed above.

Research facts

• Non-HDL cholesterol was used in the Helsinki Heart study in 1987 to randomize patients i.e., divide patients in a study into groups so that there is no bias and an equal probability of the patients receiving a particular treatment.³
• Although the control over LDL cholesterol has improved, little attention is paid to non HDL cholesterol.  As per a survey, nearly 62% of the patients suffering from coronary artery disease (CAD) were able to achieve a goal of LDL-cholesterol3
• A review by Baker et al. in 2010 stated that high levels of non-HDL cholesterol are indicative of cardiovascular risk, and the results are sensitive even without abnormal LDL levels.⁴ 
• As opposed to LDL-cholesterol measurements which require fasting, non-HDL testing can be done in non-fasting states and thus, is useful for patients who are hospitalized.³
• Further, the utility of non-HDL cholesterol in standard clinical procedures is still debatable. A more accurate evaluation of the cardiovascular disease risk will be possible with the help of a straightforward non-HDL-C calculation in lipid profile testing, in addition to the identification of the additional risk variables.

To make non-HDL cholesterol a reliable marker, awareness about the importance of non-HDL cholesterol, how to perform and calculate non-HDL cholesterol and the treatment goals should be raised.

Conclusion

Non-HDL cholesterol is the sum of all cholesterol present in all lipoproteins like VLDL (very low-density lipoproteins), and chylomicrons. To measure the level of non-HDL cholesterol in your body, your doctor will recommend a lipid panel test. This measurement requires a blood sample; your doctor will recommend a fasting or non-fasting lipid test. The level of non-HDL cholesterol is calculated by subtracting the value of HDL cholesterol from total cholesterol. The normal range of non-HDL cholesterol should be higher by approx 30mg/dL as compared to LDL-cholesterol. The use of non-HDL cholesterol in clinical practice is not a new concept; non-HDL cholesterol may help in predicting cardiovascular diseases both in the general population and in people with diabetes. 

FAQ’s

Disclaimer: The information included at this site is for educational purposes only and is not intended to be a substitute for medical treatment by a healthcare professional. Because of unique individual needs, the reader should consult their physician to determine the appropriateness of the information for the reader’s situation.

References

1. Lee Y, Siddiqui WJ. Cholesterol levels. InStatPearls [Internet] 2021 Jul 26. StatPearls Publishing. Available at: https://www.ncbi.nlm.nih.gov/books/NBK542294/
2. Bergmann K. Non-HDL cholesterol and evaluation of cardiovascular disease risk. Ejifcc. 2010 Oct; 21(3):64. Available at: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4975250/
3. Virani SS. Non-HDL cholesterol as a metric of good quality of care: opportunities and challenges. Texas Heart Institute Journal. 2011; 38(2):160. Available at: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3066801/
4. Baker RA, Forbes RA. Non-HDL cholesterol: a new endpoint in cardio-metabolic health monitoring. The Primary Care Companion for CNS Disorders. 2010 Oct 28; 12(5):27042. Available at: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3025988/
5. Lipid panel with non-HDL cholesterol [Internet]. Health encyclopedia. University of Rochester medical center; 2023. Available at: https://www.urmc.rochester.edu/encyclopedia/content.aspx?contenttypeid=167&contentid=lipid_panel_nonhdl