HDL’s anti-inflammatory function is impaired in ACS
MedWire News: The anti-oxidative capacity of high-density lipoprotein (HDL) cholesterol is reduced in acute coronary syndrome (ACS) but not in stable coronary artery disease (CAD), US research shows.
Parin Patel (University of Pennsylvania, Philadelphia) and co-investigators measured the HDL inflammatory index (HII) - a measure of how well HDL can prevent the oxidation of LDL in a cell-free environment - in 193 patients undergoing angiography for symptoms of CAD.
Of these, 99 had no angiographic CAD (controls), 51 had chronic CAD (≥70% vessel stenosis), and 43 had ACS (≥20% vessel stenosis and ischemia or infarction).
The findings, published in the Journal of the American College of Cardiology, show that ACS patients had significantly higher mean HII, and therefore less anti-oxidative capacity than controls (1.57 vs 1.17) or those with chronic CAD (1.57 vs 1.11). There were no significant differences between mean HII in chronic CAD and control patients.
On multivariate analysis, higher HII was associated with a significantly increased risk for ACS compared with controls, such that the risk increased 3.8-fold with each standard deviation increase in HII. Additionally, individuals with higher HII had a 4.8-fold increased risk for ACS compared with having chronic CAD.
"Our results are the first to our knowledge to demonstrate decreased HDL anti-inflammatory capacity in the setting of ACS," write the authors.
"The question remains, then, whether HDL with reduced anti-inflammatory capacity is a contributor or innocent bystander in acute CAD," they add.
"Improved HDL function remains an important therapeutic target, and our findings may aid in assessing therapies that increase HDL mass and also improve HDL function, in both chronic disease states and acute clinical syndromes," concludes the team.
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By Nikki Withers