Effects of simvastatin on plasma lipid, lipoprotein and apolipoprotein concentrations in hypercholesterolaemia

The effect of 24 weeks of treatment with simvastatin, a new HMG coenzyme A reductase inhibitor (dosages of 20 and 40 mg day-1) on serum lipid, lipoprotein and apolipoprotein A-I and B concentrations as well as safety parameters and subjective side effects were studied in 11 patients with familial (FH) and 10 patients with polygenic hypercholesterolaemia (P-HC). The effects on plasma lipoprotein and apolipoprotein concentrations had already been achieved after four weeks in both groups and then remained during the study. In FH, mean fasting plasma total cholesterol concentration decreased from 10.51 to 6.71 mmol l-1 (36%), and in P-HC from 6.55 to 4.54 mmol l-1 (31%) at 24 weeks (P less than 0.001). Mean plasma low density lipoprotein (LDL) cholesterol concentrations also decreased, in FH from 8.87 to 5.05 mmol l-1 (43%) and in P-HC from 4.97 to 3.12 mmol l-1 (37%) at 24 weeks (P less than 0.001). Furthermore, apolipoprotein B concentrations decreased significantly from 2.21 to 1.57 g l-1 (29%) (less than 0.001) in FH and from 1.53 to 1.09 g l-1 (29%) (P less than 0.01) in P-HC. Plasma high density lipoprotein (HDL) cholesterol increased in both FH and P-HC during treatment. Increases were seen in both the subfractions HDL2 and HDL3. Simvastatin was well tolerated. No serious clinical or laboratory adverse effects were observed. It is concluded that 24 weeks of treatment with simvastatin in doses up to 40 mg day-1 effectively reduces plasma total and LDL cholesterol concentrations without causing subjective or significant objective side effects. Thus, simvastatin may be of great interest in future studies for prevention of coronary heart disease due to hypercholesterolaemia.