Effect of pravastatin on biliary lipid composition and bile acid synthesis in familial hypercholesterolaemia.

Nine patients with heterozygous familial hypercholesterolaemia were treated for eight weeks with either 40 mg pravastatin or placebo under double blind conditions. Six patients received pravastatin, a competitive inhibitor of 3-hydroxy-3-methylglutaryl-coenzyme A (HMG-CoA) reductase. Treatment with pravastatin resulted in a significant decrease in plasma cholesterol caused by a decrease in low density lipoprotein cholesterol (LDL-c) of 30% (p less than 0.005). We determined the effect of this medication on the lithogenicity of bile. Cholesterol saturation index of fasting gall bladder bile decreased with 23% (p less than 0.01) from 1.06 to 0.75 during treatment with pravastatin. A reduction of 24% (p less than 0.01) in molar percentage of biliary cholesterol was seen. After treatment the total bile acid excretion in faeces and the molar percentage of biliary bile acids were not significantly changed, suggesting that pravastatin does not influence bile acid biosynthesis to a significant extent. These findings indicate that treatment with pravastatin can decrease the incidence and complications of cholesterol gall stones.