The Effect of Adding Plant Sterols or Stanols to Statin Therapy in Hypercholesterolemic Patients: Systematic Review and Meta-Analysis

Objective: To characterize the effect of plant sterols/stanols on serum lipids in hypercholesterolemic patients on concurrent statin therapy, we conducted a meta-analysis of randomized controlled trials. Methods: A systematic literature search of MEDLINE, EMBASE, Cochrane CENTRAL, and the Natural Medicines Comprehensive Database was conducted from the earliest possible date through May 2008. Trials were included in the analysis if they were randomized controlled trials evaluating the use of plant sterols/stanols in combination with statins in hypercholesterolemic patients that reported efficacy data on total cholesterol, low-density lipoprotein (LDL) cholesterol, high-density lipoprotein (HDL) cholesterol, or triglycerides. The weighted mean difference (WMD) of the change from baseline (in mg/dL) with 95% confidence interval (Cl) was calculated as the difference between the mean in the plant sterol/stanol groups and the control groups, using a random-effects model. Results: Eight studies (n = 306 patients) met the inclusion criteria. Upon meta-analysis, the use of plant sterols/stanols in combination with statin therapy significantly lowered total cholesterol (WMD, -14.01 mg/dL [95% Cl, -18.66 to -9.37], p < 0.0001) and LDL cholesterol (WMD, -13.26 mg/dL [95% CI, -17.34 to -9.18], p < 0.0001) but not HDL cholesterol or triglycerides. Conclusions: Based upon the current literature, we can only say that plant sterols/stanols, when administered in addition to statins, favorably affect total and LDL cholesterol with 95% confidence. Randomized trials examining the impact of plant sterols/stanols in combinatation with statins on patient morbidity and mortality are needed.