Effect of extended-release niacin on plasma lipoprotein(a) levels: A systematic review and meta-analysis of randomized placebo-controlled trials.
Level 1 - systematic review of randomized trials
Systematic review and meta-analysis of randomized placebo-controlled trials
PubMed 27733255 · doi:10.1016/j.metabol.2016.08.007
What was done
A systematic review, meta-analysis, and random-effects meta-regression were conducted on 14 randomized placebo-controlled trials (published 1998–2015) comprising 17 treatment arms and 9,013 participants (5,362 receiving extended-release niacin). The analysis assessed the effect of extended-release niacin on plasma lipoprotein(a) [Lp(a)] levels, evaluated subgroups receiving <2000 mg/day versus ≥2000 mg/day, and tested for associations with dose, treatment duration, and percentage change in HDL cholesterol.
What was found
Extended-release niacin significantly reduced plasma Lp(a) levels compared with placebo (weighted mean difference [WMD]: -22.90%, 95% CI: -27.32 to -18.48, p < 0.001; standardized mean difference: -0.66, 95% CI: -0.82 to -0.50, p < 0.001). Lower doses (<2000 mg/day; WMD: -21.85%, 95% CI: -30.61 to -13.10, p < 0.001) and higher doses (≥2000 mg/day; WMD: -23.21%, 95% CI: -28.41 to -18.01, p < 0.001) produced comparable reductions. Meta-regression found no significant association between Lp(a) changes and dose (slope: -0.0001, 95% CI: -0.01 to 0.01, p = 0.983), treatment duration (slope: -0.40, 95% CI: -0.97 to 0.17, p = 0.166), or percent change in HDL-C (slope: 0.44, 95% CI: -0.48 to 1.36, p = 0.350).
Why it matters
This meta-analysis provides a precise estimate of extended-release niacin's effect on Lp(a), demonstrating a consistent ~23% reduction that is independent of treatment duration, dose escalation beyond 2000 mg/day, or concurrent HDL-C elevation.
Limits
The abstract does not report baseline patient characteristics, baseline Lp(a) distributions, statistical heterogeneity (such as I² values), background lipid-lowering therapies, side effects, or whether the reduction in Lp(a) translated into reduced clinical cardiovascular events.
Cited by
- supports Niacin lowers circulating levels of Lipoprotein(a).