Atorvastatin calcium: OTHER ACTIONS
In a three-month study in hyperlipidemic patients, atorva-statin-induced reductions in lipoprotein levels (LDL-C, triglycerides, VLDL-C) were accompanied by significant changes in hemorheology and atherothrombotic parameters . Plasma viscosity, factor VII activity and red blood cell sedimentation were significantly reduced in all patients; however, these changes were most evident for patients with type IIb dyslipidemia. These data suggest that reductions in elevated triglyceride levels may favourably alter these hemor-heological parameters. Atorvastatin also decreased arachi-donic-induced whole blood platelet aggregation in all patients. There were no changes in other hemorheological parameters such as fibrinogen levels and plasminogen activator inhibitor-1 activity. Increased plasma viscosity, elevated levels of factor VII and platelet aggregation have been suggested to be associated with the development of atherosclerosis . Studies with other HMG-CoA reductase inhibitors have also demonstrated beneficial effects on hemorheological parameters. birth control pills
In another study, atorvastatin was reported to improve endothelial dysfunction in patients with primary hypercholesterolemia . Following six months of treatment, ator-vastatin significantly lowered plasma levels of LDL-C and triglycerides; this was accompanied by an improvement in flow-mediated dilation induced by reactive hyperemia, as assessed by brachial ultrasound.
In animal studies, atorvastatin has been shown to attenuate the development and cholesteryl ester enrichment of atherosclerotic lesions. In hypercholesterolemic rabbits, atorvas-tatin significantly reduced the discernible atherosclerotic lesions in the descending thoracic aorta and reduced subendothelial platelet deposition in mildly injured vessels . In rabbits with pre-established atherosclerosis and nearly normal plasma cholesterol, atorvastatin reduced the cholesteryl ester enrichment of the iliac-femoral artery by 37% and of the thoracic aorta by 27% to 41% without changing the extent of thoracic aortic lesions and incidence of fibrous plaques. Iliac-femoral lesion cross-sectional area and mono-cyte-macrophage content were reduced by 40% and 60%, respectively . These studies suggest beneficial, but as yet clinically unproven, antiatherosclerotic properties of atorvas-tatin.