Effect of 12‐month statin therapy on antioxidant potential of LDL and serum antioxidant vitamin concentrations

Abstract

BACKGROUND. Statins are known to cause short‐term reduction in serum lipid‐soluble antioxidant concentrations, but their long‐term effects are not known.AIM: We randomised 104 subjects with CHD and hypercholesterolaemia to receive either atorvastatin or simvastatin treatment for 52 weeks and measured the antioxidant potential of LDL and serum antioxidant vitamin concentrations.METHOD: Initial daily dose for both statins was 20 mg.RESULTS: LDL antioxidant capacity and serum α‐tocopherol, γ‐tocopherol and β‐carotene concentrations decreased by 22%–35% with both statins during the first 12 weeks' therapy (P < 0.01 for all). After 52 weeks' therapy, the concentrations of serum γ‐tocopherol in the simvastatin group and serum β‐carotene in both treatment groups returned to baseline levels, while the concentrations of serum γ‐tocopherol in the atorvastatin group and LDL antioxidant capacity and serum α‐tocopherol in both treatment groups remained reduced (P < 0.001 for all). The LDL antioxidant capacity:LDL‐cholesterol and the serum α‐tocopherol:LDL‐cholesterol ratios were significantly elevated with both statins after 12 and 52 weeks (P < 0.001 for all). Statistically significant increases were also observed for corresponding ratios of the less abundant vitamins γ‐tocopherol and β‐carotene.CONLUSIONS: Some of the decreases in serum lipid soluble antioxidant vitamins reported in short‐term statin interventions may become attenuated when therapy continues longer. The relative antioxidant capacity of LDL particles increased during the 52‐week treatment, suggesting that the oxidation resistance of LDL particles did not become impaired and that their atherogenicity did not increase.