Effects of stable fish oil and simvastatin on plasma lipoproteins in patients with hyperlipidemia

The aim of this study was to investigate the effect of a stable fish oil and simvastatin on plasma lipoproteins and erythrocyte fatty acids in patients with hyperlipidemia. Eighty-eight patients with hyperlipidemia were randomized into four groups to receive: fish oil, simvastatin, fish oil + simvastatin, or low fat diet (controls) for 12 weeks. Plasma total cholesterol (TC), triglycerides (TG), low density lipoprotein cholesterol (LDL), and high density lipoprotein cholesterol (HDL) were measured before and after treatment. Intake of 9.2 g daily of stable fish oil for 12 weeks reduced plasma TG (P < 0.0001), TC (P = 0.003), LDL (P = 0.03), the LDL/HDL ratio (P = 0.003), and the TG/HDL ratio (p < 0.0001) and increased HDL (P =0.036). Eicosapentaenoic acid (P = 0.001) and docosahexaenoic acid (P = 0.009) levels in erythrocytes increased. Intake of simvastatin 10 mg daily resulted in decreased TC, LDL, and LDL/HDL ratio (P < 0.0001). Fish oil markedly potentiated the triglyceride lowering effect of simvastatin, whereas simvastatin markedly potentiated the cholesterol reducing effect of fish oil. This study showed that simvastatin therapy with addition of stable fish oil may be more beneficial in lowering plasma lipoproteins than simvastatin or fish oil alone.