The effect of high-dose ascorbate supplementation on plasma lipoprotein(a) levels in patients with premature coronary heart disease

Abstract

Study objective: To determine the efficacy of high-dose ascorbate supplementation in lowering lipoprotein(a) [Lp(a)] levels in patients with premature coronary heart disease (CHD).

Design: Randomized, double-blind, placebo-controlled trial.

Setting: Outpatient clinic.

Patients: Forty-four patients with documented premature CHD, defined as confirmed myocardial infarction and/or angiographically determined stenosis of 50% or greater in at least one major coronary artery before age 60 years.

Interventions: Patients were block randomized on the basis of age, gender, and screening Lp(a) concentrations to receive ascorbate 4.5 g/day or placebo for 12 weeks.

Measurements and main results: High-dose ascorbate was well tolerated and produced a marked elevation in mean plasma ascorbate levels (+1.2 mg/dl; p < 0.001). Multiple linear regression analysis revealed no significant effect of supplementation on postintervention Lp(a) levels (p = 0.39) in a model that included treatment group assignment, and baseline Lp(a) levels.

Conclusions: Our findings do not support a clinically important lowering effect of high-dose ascorbate on plasma Lp(a) in patients with premature CHD.