Behavior of Lp(a) and apoproteins (A1, B, C2, C3, E) during and after therapy with simvastatin

The efficacy of simvastatin in reducing plasma cholesterol is well documented. Other molecules within the apo lipoprotein family, particularly lipoprotein (a) Lp(a), have recently been found to have a predictive and/or causative role in atherosclerosis. Based on these considerations, we studied 15 patients affected by primary hypercholesterolemia to evaluate the effect of simvastatin in Lp(a) and apoprotein plasma levels (A1, B, C2, C3, E), in addition to the classic lipid parameters. Clinical and laboratory parameters were evaluated before therapy, after 12 weeks of therapy, and after 5 weeks of drug withdrawal. Simvastatin therapy produced a significant reduction in total cholesterol (CH) and LDL-CH (p < 0.0001), and a significant increase in HDL-CH (p < 0.01); no variation was observed in triglyceride (TG) levels. Simvastatin therapy further showed a significant decrease in apoC2 (p < 0.05), the apo C2/C3 ratio (p < 0.01), and apoE (p < 0.01), as well as a significant increase in Lp(a) plasma levels (p < 0.05). All of the parameters studied returned to pretreatment values 5 weeks after drug withdrawal; only HDL-CH persisted above the values reached during therapy. Our data agree with those documenting the beneficial effect of simvastatin in greatly decreasing CH and LDL-CH, but point out the need for further studies on the long-term effect of simvastatin on apoprotein molecules, such as on Lp(a), in order to fully establish its role in the secondary prevention of atherosclerosis.