Background: Familial hypercholesterolemia (FH) is associated with a high risk of coronary heart disease. Pharmacological treatment and diet are both essential for the management of FH. Foods rich in plant sterols (PS) may play an important role in the treatment of patients with these disorders.
Objective: To test the effect of the intake of PS on low-density lipoprotein (LDL) concentration, endothelial function (EF) and LDL particle size in 30 patients with FH.
Design: Randomized and crossover dietary intervention study.
Setting: Tertiary outpatient care.
Subjects: Thirty-eight were recruited, but only 30 were subjected to four low-fat dietary intervention periods, each of 4 weeks.
Methods: Each intervention had a different content of cholesterol (<150 or 300 mg/day) and sitosterol (<1 or 2 g/day). Lipid response, EF and LDL particle size were analysed after the intervention.
Results: Plasma sitosterol/cholesterol ratio was higher during both plant sterol-rich periods than during the low plant sterols periods. Basal sitosterol concentrations predicted the LDL-cholesterol response during the intake of plant sterol-enriched diets. The change in LDL-cholesterol was significantly greater in subjects in the upper and intermediate tertiles of basal plasma sitosterol concentrations (-21+/-8 mg/dl, P=0.03; -19+/-7 mg/dl, P=0.04, respectively) than in subjects in the lower tertile (8+/-5 mg/dl) when they changed from a low cholesterol diet to a low cholesterol plus plant sterol diet.
Conclusion: Our study demonstrates that basal sitosterol values can predict hypolipidemic response in patients with FH.