Abstract
OBJECTIVE: Beyond lipid-lowering properties, statins decrease sympathetic nervous activity. Due to the limited number of studies and included participants, a meta-analysis of randomized, placebo-controlled studies using microneurography (MSNA) was performed to assess sympatholytic effect of statins. METHODS: We conducted a comprehensive search of online databases (Cochrane, Embase, and EBSCO) for published human studies up to April 2014. Randomized controlled trials (parallel and crossover design) were eligible for inclusion if results of statins versus placebo treatments on sympathetic activity were measured with MSNA. RESULTS: Data from five studies with a total number of subjects n = 82 were included into the meta-analysis. MSNA expressed as bursts/min and as bursts/100 heartbeats was lower in the statin group than in the placebo group with a mean difference of -4.37 95% CI (-7.03; -1.70), p < 0.0013 and -5.85 95% CI (-7.56; -4.13), p < 0.0001, respectively. No significant publication bias was observed. Meta-regression revealed no significant effect of baseline total cholesterol or dose of statin. No change in blood pressure and heart rate was observed. CONCLUSIONS: Published data show that regardless of type and dose, statins reduce sympathetic activity measured by microneurography. The role of decreased sympathetic outflow during statin therapy on clinical end points needs to be clarified.