|
Tuesday, March 17, 2015. The March 2015 issue of the journal Nutrition Research published the discovery of scientists at Japan's Tokai University School of Medicine of a protective effect for the omega-3 fatty acid eicosapentaenoic acid (EPA) against the risk of intracerebral hemorrhage, which is characterized by bleeding in the brain.
"Omega-3 fatty acids, including eicosapentaenoic acid, prevent ischemic stroke," write Yoshimori Ikeya and colleagues. "The preventive effect has been attributed to an antithrombic effect induced by elevated EPA and reduced arachidonic acid (AA) levels. However, the relationship between intracranial hemorrhage and
omega-3 fatty acids has not yet been elucidated."
The study included 70 men and women whose first intracerebral hemorrhage had occurred within 30-60 days, matched with 66 control subjects with no stroke history. Fasting blood samples were analyzed for plasma EPA, docosahexaenoic acid (DHA), arachidonic acid and other factors. Dietary questionnaire responses provided information concerning the participants' intake of fish (the most common source of omega-3 fatty acids) as well as other information.
Subjects who had been diagnosed with intracerebral hemorrhage had significantly higher diastolic blood pressure and other factors, lower EPA levels, and a lower average ratio of EPA to AA. Further analysis of the data revealed that low EPA was a risk factor for those aged 65 years and older.
While omega-3 fatty acids have been linked with protection against ischemic stroke, their ability to help reduce blood clotting has led to speculation that the fatty acids could increase the risk of hemorrhagic stroke, which the current finding contradicts. Dr Ikeya and colleagues note that intracerebral hemorrhages are believed to be caused by the rupture of small penetrating arteries and that changes induced by chronic hypertension can reduce these arteries' compliance (ability to distend with pressure). In addition to the antihypertensive effect of EPA, atherosclerotic plaques readily incorporate the fatty acid, resulting in plaque that has less inflammation and greater stability. "We suspect that atherosclerosis, lower compliance, and the instability of the walls of the small penetrating arteries in the brain that are produced by lower EPA concentrations eventually induce intracerebral hemorrhages," the authors write.
"Lower EPA concentrations and EPA/AA ratios were found to be risk factors for intracerebral hemorrhage in addition to previously known risk factors such as blood pressure, alcohol consumption, and lifestyle," they conclude.
|
