Inhibition of Dietary Cholesterol Absorption During Lovastatin (Mevinolin) Treatment

Abstract

Dietary butter was replaced by egg yolks in hypercholesterolaemic subjects treated with lovastatin (mevinolin) in order to record the effect of dietary cholesterol loading on serum cholesterol levels and cholesterol metabolism. The increase in cholesterol intake by 530 mg/day caused no change in total serum cholesterol, lipoprotein cholesterol or cholesterol precursor levels. Outputs of faecal bile acids were unchanged and those of neutral sterols were increased to the extent of the increase in dietary cholesterol intake, indicating that cholesterol synthesis was unchanged. Serum non-cholesterol sterol levels and sterol balance data did not suggest changes in cholesterol absorption or synthesis during the high cholesterol diet. In contrast to that in butter-fed control subjects, cholesterol absorption efficiency was significantly decreased by 25% in the cholesterol-fed patients. Calculations revealed that, owing to the decreased absorption efficiency, the increase in the intestinal cholesterol pool by dietary cholesterol was associated with increased dietary, decreased biliary and unchanged total amounts of absorbed cholesterol. Thus, impairment of cholesterol absorption by lovastatin may render a strict limitation in dietary cholesterol intake unnecessary during long term treatment.