Effects of simvastatin on blood lipids, vitamin E, coenzyme Q10 levels and left ventricular function in humans

Background As statin therapy has been reported to reduce antioxidants such as vitamin E and coenzyme Q(10) and there are indications that this reduction may cause impairment of left ventricular function (LVF), we studied the influence of simvastatin on LVF and serum vitamin E and coenzyme Q(10) levels in humans. Material and methods We assessed the effect of simvastatin on left ventricular function and coenzyme Q(10) levels in 21 (11 male, 10 female) hypercholesterolaemic subjects (mean age = 56 years) with normal LVF, over a period of 6 months. Subjects were re-tested after a 1-month wash-out period (7 months). Echocardiography was performed on all subjects before commencement of simvastatin (20 mg day(-1)), and at 1, 3, 6 and 7 months after initiation of treatment. Fasting blood samples were also collected at these intervals to assess lipids, apoproteins, vitamin E and coenzyme Q(10). Results Serum lipids showed the expected reductions. Plasma vitamin E and coenzyme Q(10) levels were reduced by 17 +/- 4% (P < 0.01) and 12 +/- 4% (P < 0.03) at 6 months. However, the coenzyme Q(10)/LDL-cholesterol ratio and vitamin E/LDL-cholesterol ratio increased significantly. Left ventricular ejection fraction (EF) decreased transiently after 1 month, while no significant change was observed at 3 and 6 months. Other markers of left ventricular function did not change significantly at any time point. Conclusion Despite reduced plasma vitamin E and coenzyme Q(10), 20 mg of simvastatin therapy is associated with a significantly increased coenzyme Q(10)/LDL-cholesterol ratio and vitamin E/LDL-cholesterol ratio. Simvastatin treatment is not associated with impairment in left ventricular systolic or diastolic function in hypercholesterolaemic subjects after 6 months of treatment.