Plant sterols lower LDL cholesterol without improving endothelial function in prepubertal children with familial hypercholesterolaemia

In adults with familial hypercholesterolaemia (FH), cholesterol lowering with statins has been shown to improve the endothelial function, a hallmark of early atherogenesis. Currently, therapeutic options for treating high cholesterol levels in FH children are limited. Plant sterols safely and effectively reduce serum cholesterol concentrations by inhibiting cholesterol absorption. Therefore, we evaluated the effect of plant sterols on cholesterol and vascular function in prepubertal children with FH. We included 41 children (5–12 years old) with FH in a double‐blind crossover trial using spreads containing 2.3 g of plant sterols (mainly sitosterol and campesterol) per 15 g spread and a placebo spread for a 4‐week period, separated by a 6‐week washout period. Lipid levels and endothelial function were assessed after both 4‐week treatment periods. Endothelial function was assessed as flow‐mediated dilation (FMD) of the brachial artery using a wall tracking system. Data were compared to those of 20 healthy controls. Intake of 2.3 g plant sterols per day decreased total cholesterol (‐11%) and low‐density cholesterol (‐14%) as compared to placebo spread in FH children. FH children treated with placebo spread were characterized by an impaired FMD compared to healthy control children (7.2 %± 3.4% versus 10.1%±4.2%, p < 0.005). However, the reduction of LDL in FH children did not improve FMD (placebo: 7.2% ± 3.4% versus plant sterols: 7.7% ± 4.1%). In conclusion, the present study shows a clear reduction of LDL cholesterol by plant sterol treatment. However, short‐term plant sterol treatment does not improve the endothelial function in FH children.