A study from Louisiana State University Health Sciences Center (LSUHSC) researchers shows how fish oil may protect against stroke from ruptured carotid artery plaques. Research led by Hernan A. Bazan, MD, Assistant Professor of Surgery, Section of Vascular Surgery, at LSU Health Sciences Center New Orleans School of Medicine, has found that unstable carotid artery plaques – those in danger of rupturing and leading to a stroke – contain more inflammation and significantly less omega-3 fatty acids than asymptomatic plaques.
This suggests that increasing the levels of omega-3 fatty acids in carotid artery plaques could either prevent strokes or improve the safety of treatment. This may be accomplished by increasing dietary intake of foods rich in omega-3 fatty acids. The study is published in the journal, Vascular Pharmacology, currently online.
Can too much fish oil can thin the blood and cause bleeding?
Our bodies produce only a small amount of omega-3 fatty acids, so most of what we need has to come from eating omega-3 fatty acid-rich foods like fish (salmon, tuna, trout, herring, etc.) or from supplements. Omega-3 fatty acids have been shown to protect against cardiovascular disease, particularly heart attack and sudden cardiac death. But Arctic peoples who eat large amounts of fish oil often suffer from a different type of stroke, not caused by blood clots, but by bleeding in the brain, as too much fish oil may thin the blood.
Dr. Bazan’s team wanted to determine what the association might be with plaques in the carotid arteries, a common cause of strokes. Vulnerable plaques which can rupture in the carotid arteries may lead to transient ischemic attacks (TIAs), strokes, 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.
Dr. Bazan, an LSUHSC vascular/endovascular surgeon, in collaboration with researchers at Yale University and others at LSUHSC, 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, in collaboration with Dr. Song Hong at LSUHSC. 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,” explains Dr. Bazan in the news release, “LSUHSC research shows fish oil may protect against stroke from ruptured carotid artery 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. About 795,000 strokes occur in the US each year and about 610,000 of these are first, or new, strokes. About 185,000 occur in people who have already had a stroke.
Nearly 25% of strokes occur in people under the age of 65. Of all ischemic strokes occurring, carotid artery atherosclerotic plaques account for over a third of them. It has been noted for several decades that the southeastern United States has the highest stroke mortality in the country. It is not completely clear what factors might contribute to the higher incidence and mortality from stroke in this region.
The research was supported by the National Institutes of Health-National Center for Research Resources, an LSUHSC Cardiovascular Center Grant (“Mentoring in Cardiovascular Biology”), and the American Vascular Association.
LSU Health Sciences Center New Orleans educates Louisiana’s health care professionals. The state’s academic health leader, LSUHSC comprises a School of Medicine, the state’s only School of Dentistry, Louisiana’s only public School of Public Health, and Schools of Allied Health Professions, Nursing, and Graduate Studies.
LSUHSC faculty take care of patients in public and private hospitals and clinics throughout the region. In the vanguard of biosciences research in a number of areas in a worldwide arena, the LSUHSC research enterprise generates jobs and enormous economic impact, LSUHSC faculty have made lifesaving discoveries and continue to work to prevent, advance treatment, or cure disease. To learn more, visit http://www.lsuhsc.edu and http://www.twitter.com/LSUHSCHealth.
Why is the southeastern part of the U.S.A. hit by more strokes than other parts of the nation? Check out the articles, The Mystery of the Southeast Stroke Belt – Newsweek and The Daily Beast and U.S. Southeast ‘Stroke Belt’ Also Shows Higher Rates of Cognitive Decline.
The ‘belt’ applies to those who live in a large swath of the southeast that stretches from the Carolinas west through Louisiana and Arkansas. The region is known as the “Stroke Belt” because its residents have a 50 percent higher risk for stroke than Americans living in other parts of the country.
Is race is an added risk–or is it traditional, familiar diets and cooking ingredients? Twice as many blacks suffer strokes as whites nationally. Researchers report that blacks in the South are about 50 percent more likely to die from stroke than blacks elsewhere, according to the American Heart Association. Is it something in the soft rather than hard water or in the diet or type of fats used in frying? Yet Japan also has a high stroke rate and consumes more salt than people in the USA. See, Relation of Adult Height With Stroke Mortality in Japan.
Could blood type be a factor? Japan has a high AB blood type rate, and people with AB blood type have a 26% more risk of stroke than other blood types. Japan also has a high number of people with B type blood, which has the next highest stroke rate, at 11%. See, Blood type might be a clue to heart disease risk – USATODAY.com.