Research suggests that increasing the levels of omega-3 fatty acids in carotid artery plaques could help prevent stroke. The researchers found that unstable carotid artery plaques in danger of rupturing and leading to a stroke contain significantly less omega-3 fatty acids than asymptomatic plaques.

According to the Centers for Disease Control and Prevention, stroke is the third leading cause of death in the United States, as well as a leading cause of serious long-term disability. Of the 795,000 strokes that occur in the US each year about 610,000 of these are new strokes. Approximately 185,000 strokes occur in people who have already had a stroke. Nearly 25% of strokes occur in people under the age of 65. Carotid artery atherosclerotic plaques account for over a third of all ischemic strokes.

Our omega-3 fatty acid requirements come from eating omega-3 fatty acid-rich foods like fish (salmon, tuna, trout, herring, etc.) or from supplements. Omega-3 fatty acids are known to protect against cardiovascular disease.

Plaques in the carotid arteries are a common cause of stroke. Vulnerable plaques which can rupture in the carotid arteries may lead to transient ischemic attacks (TIAs), stroke, or vision loss by affecting the artery to the retina. The mechanisms leading to plaque rupture are still not fully understood but inflammation within the plaque is beginning to be recognized as an important cause of plaque rupture.

The researchers analyzed plaques from 41 patients who underwent carotid endarterectomy (CEA) to remove plaque buildup in their arteries. Twenty-four patients were asymptomatic and 17 were symptomatic, having had neurological symptoms. All of the fats in the plaques were assessed with mass spectrometry. The team was measuring the amounts of docosahexaenoic acid (DHA) and eicosapentaenoic acid (EPA), the components of long-chain omega-3 polyunsaturated fatty acids. The plaques of asymptomatic patients contained more than twice as much DHA as the symptomatic patients, and about one and a half times as much EPA. Significantly less inflammation was also seen in the carotid atherosclerotic plaques from asymptomatic patients.

"In the future, a study to address whether supplementation with dietary omega-3 polyunsaturated fatty acids prevents carotid-related events in patients with moderate or high-grade carotid stenosis will help answer whether this is a formidable therapeutic target for the prevention of stroke," says study leader Hernan A. Bazan.
References:
1. Hernan A. Bazan, et al. Diminished omega-3 fatty acids are associated with carotid plaques from neurologically symptomatic patients: Implications for carotid interventions. Vascular Pharmacology, doi:10.1016/j.vph.2009.08.003.