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Medical AI Inquiry: You was designed to assist in medical decision-making based on the provided user questions. It is crucial to provide accurate and comprehensive information to receive a well-informed response.  Labels: OBJECTIVE, RESULTS. Meshes: Aged, Antioxidants, Apolipoprotein A-I, Apolipoprotein A-II, Coronary Stenosis, Disease Progression, Electrophoresis, Agar Gel, Female, Humans, Lipids, Lipoproteins, HDL, Male, Middle Aged, Niacin, Particle Size, Radiography, Simvastatin, Treatment Outcome, Vitamins.
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Does change in alpha1 HDL concentration predict progression in coronary artery stenosis? Context: We examined the effects of simvastatin-niacin and antioxidant vitamins on changes in high-density lipoprotein (HDL) subpopulations and alterations in coronary artery stenosis, as assessed by angiography. Lipids, lipoproteins, and HDL particles were measured on and off treatment in 123 subjects of the HDL-Atherosclerosis Treatment Study. Patients were assigned to 4 treatment groups, simvastatin-niacin, simvastatin-niacin-antioxidant vitamins, antioxidant vitamins, and placebo. Subjects were followed for 3 years on treatment and then for 2 months off treatment. Simvastatin-niacin significantly increased the 2 large apoA-I-containing HDL subpopulations, alpha1 and prealpha1, and significantly decreased the 2 smallest particles, prebeta1 and alpha3, compared with values obtained from the same patients off treatment. Adding antioxidant vitamins to the lipid-modifying agents blunted these effects (not significant). A significant negative correlation (r=-0.235; P<0.01) between the changes in alpha1 HDL particle concentration and coronary artery stenosis was noted. Subjects in the third tertile (157% increase in alpha1) had no progression of stenosis in the 3-year follow-up period, whereas subjects in the first tertile (15% decrease in alpha1) had an average of 2.1% increase in stenosis.
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Simvastatin-niacin therapy significantly increased the large apoA-I-containing alpha1 HDL particles. This increase was significantly associated with less progression of coronary stenosis even after adjusting for traditional risk factors. Final Decision: yes