Plasma plant sterol levels do not reflect cholesterol absorption in children with Smith-Lemli-Opitz syndrome.

Abstract

To test the hypothesis that there is a correlation between the ratio of plant sterols to cholesterol in plasma and dietary cholesterol absorption in children with Smith-Lemli-Opitz syndrome (SLOS), a cholesterol synthesis disorder. We obtained measurements of cholesterol absorption with a direct radioisotope cholesterol absorption method during 9 visits of children with SLOS. We measured plasma sterols in 22 children with SLOS and 16 control children, and we measured dietary intake of cholesterol and sitosterol (n=11 SLOS). The correlations of 2 plasma plant sterol ratios (sitosterol/cholesterol and campesterol/cholesterol) with direct cholesterol absorption measurement were poor (R= -0.33 and R= -0.25, respectively), significantly lower than the published correlation in adults (R=0.73; P< .02). Although the ratios of plant sterols to cholesterol in plasma has been used as a surrogate for cholesterol absorption in adults and children, these ratios may not accurately reflect cholesterol absorption in children with SLOS. These ratios should not be used as a surrogate for cholesterol absorption in children without further validation.