Abstract 5144: Extended-Release Niacin Reduces LDL-C Particle Number Even In The Absence Of Changes In Total LDL-C Levels
Introduction: The importance of the number of circulating low-density lipoprotein cholesterol (LDL-C) particles, in addition to the total level of LDL-C is increasingly recognized. The effects of Extended Release Niacin (ERN) on LDL-C particle number have not been studied. The primary objective of this study was to evaluate ERN’s effects on LDL-C particle number. ERN’s effect on high-density lipoprotein cholesterol (HDL-C) particle number was a secondary objective.
Hypothesis: In patients with stable coronary artery disease (CAD) and LDL-C at goal, the addition of ERN will favorably alter LDL-C particle number.
Methods: 60 patients with stable CAD and well-controlled LDL-C levels were randomly assigned to 3 months of ERN (1g/d) or placebo in addition to their baseline medications. Particle number was analyzed by proton nuclear magnetic resonance spectroscopy at baseline and after 3 months.
Results: Baseline and follow up lipid values are shown in Table⇓. Compared to baseline, while ERN had no significant effect on total LDL-C levels, it significantly decreased the mean number of medium and small very small LDL-C particles (p=0.005). The percent change in each of these particle numbers was significantly greater in the ERN group compared to placebo as well (p<0.05 for each) ERN therapy raised HDL-C levels and also significantly shifted from small to large HDL-C particles (p<0.001). There were no significant changes in lipid values or particle numbers in the placebo-treated patients (Table⇓).
Conclusion: In patients with stable CAD and well-controlled LDL-C levels, ERN significantly reduced the number of circulating particles of the more atherogenic subtypes of LDL-C, despite having no effect on total LDL-C levels. ERN also favorably altered particle numbers of HDL-C. These findings suggest that ERN-induced alterations in particle number may contribute to its anti-atherosclerotic effects, and that these effects may not be evident from the standard lipid profile.