Effect of niacin and atorvastatin on lipoprotein subclasses in patients with atherogenic dyslipidemia

This study was conducted to determine the efficacy of atorvastatin and niac in on lipoprotein subfractions in patients with atherogenic dyslipidemia. T his was a multicenter, randomized, open-label, parallel-design study of pat ients with total cholesterol > 200 mg/dl, triglycerides between 200 and 800 mg/dl, and apolipoprotein B > 110 mg/dl. Patients were randomly assigned t o atorvastatin 10 mg or immediate release niacin 3,000 mg daily for 12 week s following a low-fat diet stabilization period. Lipoprotein subclasses wer e measured by nuclear magnetic resonance spectroscopy. Atorvastatin and nia cin both significantly reduced the concentrations of very low-density lipop rotein (VLDL) particles (-31% and -29%, respectively) and small low-density lipoprotein (LDL) particles (-44% and -35%, respectively). Niacin increase d the concentration of large LDL (+75%). Atrovastatin reduced the number of LDL particles more than niacin (31% vs 14%). In patients with atherogenic dyslipidemia, both drugs had important effects on lipoprotein subfractions, which contributed to a reduction in coronary heart disease risk. The drugs equally reduced VLDL subclass levels. Niacin shifted the LDL subclass dist ribution toward the larger particles, more effectively converted patients f rom LDL phenotype B to phenotype A, and increased levels of the larger and perhaps more cardioprotective high-density lipoprotein particles. In contra st, atorvastatin preferentially lowered the concentration of small LDL part icles without increasing levels of large LDL, and more effectively, reduced LDL particle numbers. Atorvastatin had a preferred LDL effect, whereas nia cin had a preferred high-density lipoprotein effect. (C) 2001 by Excerpta M edica, Inc.