OBJECTIVES:
Patients with peripheral artery disease (PAD) experience significant morbidity and mortality, at least partially related to vascular inflammation and endothelial dysfunction. The OMEGA-PAD I Trial (NCT01310270), a randomized, double-blinded, placebo-controlled trial addressed the hypothesis that short-duration, high-dose n-3 polyunsaturated fatty acids (n-3 PUFA) oral supplementation improves endothelial function (EF) and inflammation in subjects with PAD.
METHODS:
Eighty patients with stable, mild-severe claudication and ABI<0.9 received 4.1gm of fish oil (FISH) vs placebo capsules (CTL) for 1 month. The primary endpoint was EF as measured by brachial artery flow-mediated vasodilation (FMD). Secondary endpoints included biomarkers of inflammation, generation of n-3 fatty acid-derived lipid metabolites, lipid profile and walking impairment questionnaires.
RESULTS:
The FISH and CTL group were no different with regards to age, baseline EF, inflammation and lipid profiles. Following treatment, there was a significant reduction in triglycerides (-34 ± 46, p=0.0001) and an improvement in HDL (+2 ± 6, p=0.03) in the FISH group. These changes were accompanied by an increase in the omega-3 index of 4 ± 1% (p<0.00001). We observed a significant increase in the production of downstream metabolites of n-3 fatty acids including 18-, 15- and 5-hydroxy eicosapentaenoic acids and 4-hydroxy docosahexaenoic acid in the FISH group. n-3 PUFA led to a significant improvement in FMD in the FISH group (+0.7 ± 4.0%, p=0.04) and a non-significant improvement in the CTL (+0.6 ± 2.5, p=0.18) group. There were no significant differences between groups in pro-inflammatory markers or walking parameters post-treatment.
CONCLUSIONS:
High-dose, short-duration n-3 PUFA supplementation significantly improves the metabolo-lipidomic profile of patients with PAD. Longer studies are needed to assess the effects of n-3 PUFA on inflammation, vascular function, and clinical endpoints in patients with established PAD and to determine whether generation of n-3 fatty acid-derived bioactive lipid mediators is related to clinical outcomes.
The Association Between Erythrocyte n-3 Polyunsaturated Fatty Acids (n-3 PUFAs) Content and Inflammation in Male Patients With Peripheral Artery Disease (PAD)