Addition of marine omega-3 fatty acids to statins in familial hypercholesterolemia does not affect in vivo or in vitro endothelial function.

Background: Prestatin trials reported positive effects of omega-3 polyunsaturated fatty acids (n-3 PUFA) in cardiovascular disease, whereas recent studies and meta-analyses have not reproduced these results. The effect of n-3 PUFA in patients with familial hypercholesterolemia (FH), a group with particularly high risk of cardiovascular disease, is not well established.

Objective: We investigated the effect of n-3 PUFA in the early stage of atherosclerosis in FH patients by evaluating in vivo (peripheral arterial tonometry [PAT]) and in vitro (plasma asymmetric dimethylarginine and E-selectin) endothelial function.

Methods: This was a double-blind, placebo-controlled cross-over study with 34 FH patients on statin treatment (mean age 46.6 years). In random order, all individuals were treated for 3 months with high-dose n-3 PUFA (2 g, ×2) and 3 months placebo (olive oil, 2 g ×2), separated by a 3-month washout period. Anthropometric data, blood samples, and PAT were collected at 4 time points.

Results: There were no significant changes in reactive hyperemia index measured by PAT after n-3 PUFA compared with placebo, median reactive hyperemia index after n-3 PUFA was 1.98 and after placebo 1.96 (P = .51). No significant changes were detected in the soluble endothelial marker asymmetric dimethylarginine (in 2 different assays) when comparing n-3 PUFA and placebo (P = .92 and .14, respectively). Finally, the level of E-selectin did not change significantly during the trial (P = .26).

Conclusion: Addition of n-3 PUFA to standard lipid-lowering treatment in genetically verified FH patients did not affect the in vivo endothelial function or soluble endothelial markers.