Treatment with omega-3 polyunsaturated fatty acids does not improve endothelial function in patients with type 2 diabetes and very high cardiovascular risk: A randomized, double-blind, placebo-controlled study (Omega-FMD).

BACKGROUND AND AIMS: Numerous recent studies conducted in different clinical settings have focused on the benefits of omega-3 polyunsaturated fatty acids (n-3 PUFAs) in the prevention of cardiovascular diseases. There is limited evidence that patients with type 2 diabetes (T2D) and very high cardiovascular risk can also benefit from a high dose of n-3PUFAs, especially those on optimal medical therapy as recommended by the guidelines. The aim of the present study was to assess the impact of high-dose n-3 PUFA treatment on endothelial function in patients with T2D and established atherosclerotic cardiovascular disease (ASCVD). METHODS: We conducted a prospective randomized double-blind, placebo-controlled, 2-center study, in which endothelial function was measured using flow-mediated dilation (FMD) and nitroglycerin-mediated dilation (NMD). Serum fatty acids composition was measured by gas chromatography. All measurements were done at baseline and after 3 months of treatment with PUFAs at a dose of 2 g/d (n = 36) or placebo (n = 38). RESULTS: The majority of the study population was treated with optimal medical therapy. Despite significantly higher concentrations of eicosapentaenoic acid (EPA) and docosahexaenoic acid in the n-3 PUFA group after 3-month treatment, we did not observe significant changes in endothelial function indices (FMD and NMD). However, in regression analysis, only baseline FMD was associated with EPA concentration before 3 months of n-3 PUFA treatment. CONCLUSIONS: Three months of high-dose n-3 PUFA treatment in very high-risk patients with ASCVD and T2D did not improve the endothelial function indices.

Treatment with high-dose n-3 PUFAs has no effect on platelet function, coagulation, metabolic status or inflammation in patients with atherosclerosis and type 2 diabetes.

BACKGROUND: Despite numerous studies on cardioprotective effects of omega-3 polyunsaturated fatty acids (n-3 PUFAs), there is limited evidence for n-3 PUFA-mediated effects, especially at its higher dose, on cardiovascular risk in patients with type 2 diabetes (DM2) and established atherosclerosis. PURPOSE: To investigate the effect of daily treatment with a higher dose (2 g) of n-3 PUFAs on platelet function, coagulation parameters, fibrin clot properties, markers of systemic inflammation and metabolic status, in patients with atherosclerotic vascular disease and DM2 who receive optimal medical therapy. METHODS: We conducted a prospective, double-blind, placebo-controlled, randomized, double-center study, in which thrombin generation (plasma thrombogenic potential from automated thrombogram), fibrin clot properties (plasma fibrin clot permeability; lysis time), platelet aggregation (light transmission aggregometry with adenosine diphosphate and arachidonic acid used as agonists), HbA1c, insulin level, lipid profiles, leptin and adiponectin levels, as well as markers of systemic inflammation (i.e., hsCRP, IL-6, TNF-α, ICAM-1, VCAM-1, and myeloperoxidase) were determined at baseline and at 3 months after treatment with 2 g/day of n-3 PUFAs (n = 36) or placebo (n = 38). Moreover, we assessed serum fatty acids of the phospholipid fraction by gas chromatography both at baseline and at the end of the study. RESULTS: Majority of patients were treated with optimal medical therapy and achieved recommended treatment targets. Despite higher serum levels of eicosapentaenoic acid (EPA) (by 204%; p < 0.001) and docosahexaenoic acid (DHA) (by 62%; p < 0.0001) in n-3 PUFA group at the end of treatment no changes in platelet aggregation, thrombin generation, fibrin clot properties or markers of systemic inflammation were observed. No intergroup differences in the insulin, HbA1c and lipid levels were found at the end of the study. There was no change in adiponectin and leptin in interventional group, however leptin increased in control group (p = 0.01), therefore after study period leptin levels were lower in the interventional group (p = 0.01). Additionally, resolvin D1 did not differ between interventional and control group. CONCLUSIONS: In conclusion, our study demonstrated that in patients with long-standing, well-controlled DM2 and atherosclerotic disease the treatment with a high dose of n-3 PUFAs (namely, 1 g/day of EPA and 1 g/day of DHA for 3 months) does not improve coagulation, metabolic, and inflammatory status when measured with the specified tests. The study was registered in ClinicalTrials.gov; identifier: NCT02178501. Registration date: April 12, 2014.