Can Different Types of Cholesterol Increase Your Chances of Getting Heart Disease?

---

Joint distribution of non-HDL and LDL cholesterol and coronary heart disease risk prediction among individuals with and without diabetes, by J. Liu and colleagues. Diabetes Care 28:1916-1921, 2005.

What is the problem and what is known about it so far?

We all need some cholesterol (a waxy fat-like substance that is found in foods and produced by the body) in our blood to keep our organs working. There are different types of cholesterol; some help to keep the arteries clear, and some can cause buildup that leads to heart disease. HDL cholesterol is a "good" kind of cholesterol that helps to remove plaque from the blood by delivering it to other parts of the body (such as the liver). LDL and VLDL are "bad" cholesterols that contain triglycerides, which can stick to artery walls and cause damage to the heart. For people with diabetes, the extra glucose in their blood sticks to cholesterol particles and clogs the arteries, causing high blood pressure, strokes, and heart attacks.

Why did the researchers do this particular study?

Few studies have been done to determine which types of cholesterol can cause heart disease, especially in people with diabetes. People with diabetes are 200% more likely to develop coronary heart disease than the general population.

Who was studied?

A total of 19,381 people completed the study. The participants were white men and women who were at least 30 years old and had no history of coronary heart disease.

How was the study done?

Researchers studied the participants for 13 years. They used data from four other studies to find information about the participants' cholesterol and triglyceride levels, diabetes status, and their chances of getting coronary heart disease.

What did the researchers find?

People with diabetes were more likely to have higher LDL and VLDL, or "bad" cholesterol levels, which greatly increased their chances of getting coronary heart disease. During the 13 years of the study, more than 10% of the diabetic participants died from coronary heart disease, as compared with about 3% of participants without diabetes. Each increase in LDL or VLDL cholesterol levels caused an increased risk of getting coronary heart disease. The researchers found that participants with a combined LDL and VLDL cholesterol level of 130 mg/dl or more were the most likely to die from coronary heart disease.

What are the limitations of the study?

The researchers applied a new definition of diabetes provided by the American Diabetes Association to information that had already been collected, which could have affected the results. Because the participants were all white men and women, the results may not apply to the overall population.

What are the implications for the study?

People with diabetes should have their cholesterol checked regularly and should try to get their LDL and VLDL cholesterol levels as low as possible to reduce the risk of getting coronary heart disease. In addition to eating a healthy, low-fat diet, drugs called statins can also help to lower LDL and VLDL cholesterol levels.

For more information

Diabetes: A Practical Guide to Managing Your Health, by Rosemary Walker and Jill Rodgers (Alexandria, VA, ADA, 2005).

Non-HDL Cholesterol and Apolipoprotein B Predict Cardiovascular Disease Events Among Men With Type 2 Diabetes, by R. Jiang and colleagues. Diabetes Care 27:1991–1997, 2004.

Diabetes, Cholesterol, and Heart Disease

Statins Reduce Cholesterol, Heart Risk for People With Diabetes