BACKGROUND: Although a cholesterol-lowering diet and the addition of plant sterols and stanols are suggested for the lipid management of children and adults with familial hypercholesterolemia, there is limited evidence evaluating such interventions in this population.
OBJECTIVE: To investigate the impact of cholesterol-lowering diet and other dietary interventions on the incidence or mortality of cardiovascular disease and lipid profile of patients with familial hypercholesterolemia.
METHODS: Relevant trials were identified by searching US National Library of Medicine National Institutes of Health Metabolism Trials Register and clinicaltrials.gov.gr using the following terms: diet, dietary, plant sterols, stanols, omega-3 fatty acids, fiber and familial hypercholesterolemia.
METHODS: Randomized controlled trials evaluating the effect of cholesterol-lowering diet or other dietary interventions in children and adults with familial hypercholesterolemia were included.
METHODS: Two authors independently assessed the eligibility of the included trials and their bias risk and extracted the data which was independently verified by other colleagues.
RESULTS: A total of 17 trials were finally included, with a total of 376 participants across 8 comparison groups. The included trials had either a low or unclear bias risk for most of the assessed risk parameters. Cardiovascular incidence or mortality were not evaluated in any of the included trials. Among the planned comparisons regarding patients\' lipidemic profile, a significant difference was noticed for the following comparisons and outcomes: omega-3 fatty acids reduced triglycerides (mean difference (MD): -0.27 mmol/L, 95% confidence interval (CI): -0.47 to -0.07, p < 0.01) when compared with placebo. A non-significant trend towards a reduction in subjects\' total cholesterol (MD: -0.34, 95% CI: -0.68 to 0, mmol/L, p = 0.05) and low-density lipoprotein cholesterol (MD: -0.31, 95% CI: -0.61 to 0, mmol/L, p = 0.05) was noticed. In comparison with cholesterol-lowering diet, the additional consumption of plant stanols decreased total cholesterol (MD: -0.62 mmol/L, 95% CI: -1.13 to -0.11, p = 0.02) and low-density lipoprotein cholesterol (MD: -0.58 mmol/L, 95% CI: -1.08 to -0.09, p = 0.02). The same was by plant sterols (MD: -0.46 mmol/L, 95% CI: -0.76 to -0.17, p < 0.01 for cholesterol and MD: -0.45 mmol/L, 95% CI: -0.74 to -0.16, p < 0.01 for low-density lipoprotein cholesterol). No heterogeneity was noticed among the studies included in these analyses.
CONCLUSIONS: Available trials confirm that the addition of plant sterols or stanols has a cholesterol-lowering effect on such individuals. On the other hand, supplementation with omega-3 fatty acids effectively reduces triglycerides and might have a role in lowering the cholesterol of patients with familial hypercholesterolemia. Additional studies are needed to investigate the efficacy of cholesterol-lowering diet or the addition of soya protein and dietary fibers to a cholesterol-lowering diet in patients with familial hypercholesterolemia.

OBJECTIVE: Regular intake of phytosterols (PS) is proven to dose-dependently lower LDL-cholesterol (LDL-C). Whether PS consumption can also impact low-grade inflammation is unclear. Considering the low feasibility of outcomes studies involving PS consumption, investigation of surrogate markers of atherosclerosis represents a valuable approach. This study assessed the anti-inflammatory effect of PS consumption, according to inflammatory biomarkers, mainly C-reactive protein (CRP).
RESULTS: A systematic search of Medline, Cab Abstracts, and Food Science & Technology Abstracts was conducted through January 2015. Our study selection included randomized controlled trials (RCT), involving intake of PS-enriched foods as active treatment, and measurement of plasma inflammatory biomarkers. Random-effects meta-analyses were performed using average baseline and end-of-intervention concentrations and control-adjusted absolute changes in CRP and blood lipids. There were 20 eligible RCTs including a total of 1308 subjects. The absolute change of plasma CRP levels with PS consumption was -0.10 mg/L (95%CI -0.26; 0.05), a non-significant change, and heterogeneity had borderline significance (I(2) = 29.1; p-value = 0.073). The absolute reduction of LDL-C was -14.3 mg/dL (95%CI -17.3; -11.3). Meta-regression analyses showed that both the dose and duration of PS intake significantly influenced the absolute changes in plasma CRP (β = -0.35, p = 0.0255 and β = -0.03, p = 0.0209, respectively).
CONCLUSIONS: In this meta-analysis, regular intake of PS-enriched foods did not significantly change CRP, whilst LDL-C concentrations were significantly reduced. Further studies with higher PS doses may provide more definite conclusions on a potential anti-inflammatory effect of PS intake.