Patients taking statin drugs achieve better blood lipid profiles with added phytosterols, meta-analysis shows
- Meta-analysis of 15 randomized, controlled trials involving 500 patients treated with statin drugs
- Plant sterol/stanol supplementation from 1.8 to 6 g/day
- Median study duration is 6 weeks (range 4 to 85 weeks)
- Significant reduction in total and LDL cholesterol compared to statin treatment alone
This meta-analysis was conducted to evaluate the overall effect of plant sterol- and/or stanol-enriched diets on blood lipid profiles in patients treated with statins.
The researchers completed a literature search (PubMed, Cochrane library and ClinicalTrials.gov databases) to find relevant clinical trials published up to December 2015. Inclusion criteria included randomized, controlled trials at least 4 weeks in duration that evaluated the effect of plant sterols or stanols in patients taking statin drugs. The trials were also required to report net changes for at least one of four lipid endpoints: total cholesterol, low-density lipoprotein (LDL) cholesterol, high-density lipoprotein (HDL) cholesterol or triglycerides. When more than one follow-up time point was mentioned, data from the longest period were used.
A total of 15 clinical trials with 500 participants met the inclusion criteria and were included in the meta-analysis. Treatment dosages ranged from 2 to 6 g/day (sterols) and 1.8 to 3 g/day (stanols) with or without other dietary or lifestyle guidance. The duration of study interventions ranged from 4 to 85 weeks with a median of 6 weeks.
Results are reported as the weighted mean difference (WMD) with 95% confidence intervals (CI). Heterogeneity was assessed with I-squared (I2) and Cochrane’s Q tests. Publication bias and subgroup analyses were also performed.
The authors report no statistical heterogeneity in total cholesterol, LDL cholesterol, HDL cholesterol and triglyceride analyses (I2 = 0% for all) and thus used a fixed-effect model for analyses. No publication bias was reported.
Results indicate that the sterol- or stanol-enriched diets significantly (P<.05) reduced total cholesterol (WMD: 0.30 mmol/L ; 95% CI -0.36 to -0.25, P<.05) and LDL cholesterol (WMD: 0.30 mmol/L; 95% CI -0.35 to -0.25, P<.05) compared to statin treatment alone. No significant effect was reported for changes in HDL cholesterol or triglycerides. These results persisted in the subgroup analysis.
These findings indicate that, for patients treated with statin drugs, a diet enriched with plant sterols or stanols additionally lowers total cholesterol and LDL-cholesterol levels beyond that achieved by statin drugs alone.