Another way 'good' cholesterol is good: combatting inflammation

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Testing how well “good” cholesterol particles reduce inflammation can help predict who is at increased risk of developing cardiovascular disease caused by narrowed arteries. This is based on research published today in the American Heart Association’s flagship journal Circulation.

The determination of HDL cholesterol (high density lipoprotein), known as “good cholesterol”, is already a standard part of the formulas for predicting cardiovascular risk. A new test of HDL’s anti-inflammatory function appears to provide additional information that is independent of the amount of HDL. With results confirmed in broader populations and a test developed for clinical use, adding anti-inflammatory capacity to risk assessments can improve risk outlook and help people take steps to protect themselves from heart disease.

“HDL are very complex particles with anti-atherosclerotic functions that are not only reflected in the measurement of the amount of cholesterol,” said lead study author Uwe JF Tietge, MD, Ph.D., professor and head of the department of clinical chemistry at Karolinska Institute in Stockholm, Sweden. “Atherosclerosis [plaque build-up in the arteries] The underlying cardiovascular disease is increasingly recognized as a disease with a strong inflammatory component, and a central biological function of HDL is to reduce inflammation. “

This study is the first to test whether better anti-inflammatory function of HDL particles protects against heart attacks and other serious heart-related events.

Participants included 680 white adults (mean age 59, 70% men) who lived in the Netherlands and were part of a large population study that began in 1997. All were healthy when they took part in the study. From the larger study, participants were identified who had an initial cardiovascular event before the end of the follow-up visit. HDL particles were analyzed in 340 people who had a first-time fatal or non-fatal myocardial infarction, who were diagnosed with heart problems caused by narrowing heart arteries (ischemic heart disease), or who had a procedure to open clogged coronary arteries during the mid-period Follow-up time of 10.5 years was required. These participants were assigned to a control group of 340 people of the same age (within 5 years), gender, smoking status, and HDL cholesterol level who had no cardiovascular events during follow-up.

Several laboratory tests were performed for all participants at enrollment, including measuring the ability of isolated HDL particles to reduce the inflammatory response of endothelial cells that line blood vessels (known as anti-inflammatory capacity). The researchers also measured C-reactive protein, a substance that increases with more inflammation throughout the body, and cholesterol outflow capacity, a laboratory assessment of how efficiently HDL can remove cholesterol from cells similar to those in plaque.

The researchers found:

  • The HDL anti-inflammatory capacity was significantly higher in people who remained healthy (31.6%) than in people who had a cardiovascular event (27%).
  • The association of anti-inflammatory capacity with cardiovascular events was independent of the established biomarkers for HDL cholesterol and C-reactive protein levels and was also independent of the cholesterol outflow capacity;
  • For every 22% increase in the ability of HDL particles to suppress inflammation in endothelial cells, participants were 23% less likely to have a cardiovascular event over the next decade.
  • The level of protection from increased HDL anti-inflammatory capacity was higher in women than in men; and
  • Risk prediction has been improved by adding an anti-inflammatory HDL capacity to the Framingham Risk Score or by replacing HDL cholesterol with this new measure of HDL function.

“Using a novel research tool, our results support the concept that plaque build-up in the arteries has an inflammatory component and that the biological properties of HDL particles are clinically relevant in predicting the risk of cardiovascular disease,” said Tietge.

Although the results offer interesting opportunities for improved screening, the results need to be confirmed in different populations. In addition, a simpler and hopefully automated test for anti-inflammatory properties should be developed first, the researchers said.

“HDL cholesterol is a good, well-established, simple and inexpensive biomarker of CVD risk. However, our results show that anti-inflammatory capacity or the tests used to study HDL function in general have the potential to provide clinically relevant information about cholesterol levels It also provides static HDL cholesterol measurements that are currently in use, “Tietge said.

The results also increase the possibility that drugs to improve HDL anti-inflammatory capacity can be developed and used to lower the risk of heart disease.

Study limitations to consider include that the study population was white and genetically similar such that the results are not generalizable to other races and ethnic groups. In addition, the researchers did not include stroke incidence in their analysis, so no conclusions can be drawn about HDL and stroke.

Not all “good” cholesterol is healthy

More information:
“HDL Anti-Inflammatory Capacity and Cardiovascular Events”, Circulation (2021). DOI: 10.1161 / CIRCULATIONAHA.120.050808 Provided by the American Heart Association

Quote: Another way ‘good’ cholesterol is good: Combating Inflammation (2021 April 12), accessed April 12, 2021 from https://medicalxpress.com/news/2021-04-good-cholesterol-combatting -inflammation.html

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