Peripheral artery disease (PAD) is a global health problem that affects more than two hundred million people worldwide with evidence of increasing incidence. PAD is a disease of systemic atherosclerosis and has been associated with an increased risk of adverse cardiovascular events and mortality as well as high morbidity due to claudication symptoms, impaired quality of life, and risk of amputation. Additionally, PAD has been associated with elevated levels of inﬂammation, and markers of systemic inﬂammation have been reported to predict mortality and poor surgical outcomes among this population
PAD is a disease that affects the blood vessels outside the heart and brain. Evidence from other studies suggests that omega-3s affect many steps of the atherosclerotic process. More specifically, they improve endothelial function; promote vasodilatation through relaxation of smooth muscle cells; exert antioxidant, anti-inflammatory, and antithrombotic actions; delay development of plaques and increase their stability; and decrease wall stiffening.
The level of omega-3’s can be measured using an omega-3 index test. This test is a measurement of erythrocyte membrane content of the predominant n-3 PUFA, eicosapentaenoic acid (EPA), and docosahexaenoic acid (DHA) (von Schacky, 2011). It is also a simple and accurate measurement of long-term n-3 PUFA intake and correlates strongly with plasma and tissue n-3 PUFA content. A lower omega-3 index has been associated with increased systemic inﬂammation and cardiovascular and all-cause mortality.
To study the relationship between the Omega-3 Index and PAD, a recent study compared the Omega-3 Index in 145 patients with PAD to 34 controls without PAD. The study was recently published in the March 18th edition of Lipids .
They found that the Omega-3 Index was significantly lower in the PAD patients than the controls (5% vs 6%).When they controlled for other patient characteristics that might have influenced these findings (like age, smoking, blood pressure, diabetes, drugs, etc.), the Omega-3 Index was still lower in the cases vs. the controls.
In the final analysis, for every 1% unit reduction in the Omega-3 Index, the odds of being a PAD patient increased by 39%, and for every additional pack-year of smoking the odds of being a PAD case increased by 4%.
“It is likely that the lower inflammatory burden associated with a higher Omega-3 Index may be part of the explanation for these results,” said Bill Harris, PhD, one of the study’s authors. “Whether long-term use of omega-3 supplements and/or increased consumption of oily fish could prevent the development of PAD should be examined in future studies.”