Predictors of endothelial function improvement in patients with mild hypertriglyceridemia without evidence of coronary artery disease treated with purified eicosapentaenoic acid.

Background And Aims: Eicosapentaenoic acid (EPA) has been reported to reduce cardiovascular risk in patients with hypertriglyceridemia. Although several mechanisms underlying the effects of EPA have been demonstrated, those responsible for its beneficial role in patients with hypertriglyceridemia without evidence of coronary artery disease (CAD) have not been fully elucidated. We sought to clarify the main factors associated with EPA administration that led to improved endothelial function.

Methods: Forty-seven consecutive patients with mild hypertriglyceridemia (mean age, 59 ± 13 years) without evidence of CAD were prospectively enrolled and administered purified EPA (1800 mg/day). Forty-four patients who were not administered EPA were enrolled as age- and sex-matched controls. Clinical variables and flow-mediated dilation (FMD) were examined before and after 6 months of treatment. Univariate and multivariate regression analyses were performed between FMD changes and clinical variables.

Results: EPA treatment decreased triglyceride levels (from 224.6 ± 58.8 to 151.8 ± 54.5 mg/dl, p < 0.001) and increased FMD (from 4.21% ± 1.91% to 6.21% ± 2.30%, p < 0.001). Multivariate analysis showed that the change in FMD was associated with the baseline high-density lipoprotein cholesterol (HDL-C) level (β = -0.331, p = 0.027) and the change in EPA/arachidonic acid (AA) ratio (β = 0.301, p = 0.048).

Conclusions: EPA treatment improved triglyceride levels and FMD in patients with mild hypertriglyceridemia and without evidence of CAD. The baseline HDL-C level and the change in EPA/AA ratio predicted FMD improvement. The beneficial effects of EPA on triglyceride-rich lipoproteins and vascular endothelium may help improve endothelial function.