Suplementación AG Omegas 3 para beneficios cardiovasculares

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Todos los estudios realizados este año, como el que ha copiado veganauta, vienen a decir que no está justificado recomendar un suplemento de DHA a los vegetarianos, por ejemplo (creo que ya se ha nombrado también):

"Do vegetarians have to eat fish for optimal cardiovascular protection? (2008)

Interest in the cardiovascular protective effects of n–3 (omega-3) fatty acids has continued to evolve during the past 35 y since the original research describing the low cardiovascular event rate in Greenland Inuit was published by Dyerberg et al. Numerous in vitro experiments have shown that n–3 fatty acids may confer this benefit by several mechanisms: they are antiinflammatory, antithrombotic, and antiarrhythmic. The n–3 fatty acids that have received the most attention are those that are derived from a fish source: namely, the longer-chain n–3 fatty acids eicosapentaenoic acid (EPA; 20:5n–3) and docosahexaenoic acid (DHA; 22:6n–3). More limited data are available on the cardiovascular effects of n–3 fatty acids derived from plants such as {alpha}-linolenic acid (ALA; 18:3n–3). Observational data suggest that diets rich in EPA, DHA, or ALA do reduce cardiovascular events, including myocardial infarction and sudden cardiac death; however, randomized controlled trial data are somewhat less clear. Several recent meta-analyses have suggested that dietary supplementation with EPA and DHA does not provide additive cardiovascular protection beyond standard care, but the heterogeneity of included studies may reduce the validity of their conclusions. No data exist on the potential therapeutic benefit of EPA, DHA, or ALA supplementation on those individuals who already consume a vegetarian diet. Overall, there is insufficient evidence to recommend n–3 fatty acid supplementation for the purposes of cardiovascular protection; however, ongoing studies such as the Alpha Omega Trial may provide further information."
http://www.ajcn.org/cgi/content/abstract/89/5/1597S

No existen datos sobre los potenciales beneficios terapéuticos de la suplemetación de EPA, DHA o ALA sobre aquellos individuos que ya llevan una dieta vegetariana. En general, hay pruebas insuficientes para recomendar la suplementación de ácidos grasos n-3 para los objetivos de protección cardiovascular; sin embargo, estudios en curso como el Alpha Omega Trial pueden proporcionar información adicional.

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OMEGA trial: No extra benefit of fish oils post-MI
30 March 2009

MedWire News: Omega-3 fatty acids do not offer patients who have had an acute myocardial infarction (MI) any further benefits over optimal medical therapy, results of the OMEGA (randomized trial of OMEGA-3 fatty acids on top of modern therapy after acute myocardial infarction) trial suggest.

The OMEGA trial resulted in ‘superimposable’ survival curves at 1 year. The primary endpoint of sudden cardiac death (SCD) occurred in 1.5% of patients given a prescription-only omega-3 fatty acid preparation and in 1.5% of patients given olive oil as a placebo.

“We had an unexpected low rate of sudden cardiac deaths,” said Dr. Jochen Senges (Heart Center Ludwigshafen, University of Heidelberg, Germany), who presented the late-breaking trial findings at the ACC.09 58th Scientific Session here in Orlando, Florida. He noted that this had resulted in the study being underpowered to detect a statistically significant difference. However, “there was no trend favoring omega-3s in this population of high-risk myocardial infarction patients on optimal treatment.” It is doubtful if longer-term treatment would alter this finding, he suggested.

The prospective, double-blind OMEGA trial was conducted in 104 centers in Germany and involved a total of 3851 patients who had an acute MI. Of these, 1940 patients were randomized to receive 1 g/day of an omega-3 fatty acid preparation containing 460 mg of eicosapentaenoic acid (EPA) and 380 mg of docosahexaenoic acid (DHA). The remaining patients were randomized to receive 1 g/day of olive oil. Treatment was for 1 year.

The mean age of randomized patients was 64 years, around 27% had diabetes, 60% had ST-elevation MI, and one quarter had a low (<45%) ejection fraction. This was a fairly typical MI population, Dr. Senges said.

Around three quarters of patients underwent primary or early percutaneous coronary intervention, and the majority was treated with an antiplatelet (aspirin, 94%; clopidogrel, 88%; glycoprotein IIb/IIIa inhibitor, 43%), antihypertensive (beta-blocker, 85%; ACE-inhibitor, 69%), and lipid-lowering agent (statin, 81%).

Secondary endpoints included the number of deaths at 1 year, re-infarction, stroke, major adverse cardiac events, arrhythmic events, progression of coronary artery disease, revascularization, PCI, coronary artery bypass grafting, and rehospitalization. No significant difference in the rates of these events was seen in the patients who received the EPA/DHA-containing omega-3 fatty acid preparation as compared to those who received placebo.

Commenting on the study for MedWire, Dr. Frans J. J. Van de Werf (Gasthuisberg University Hospital, Leuven, Belgium) said: “I think if you give optimal secondary prevention, which has been given in this trial, it is hard to get any additional benefit.”

He noted that the choice of olive oil as the placebo could have had an effect on the findings. Also it was unclear what the dietary recommendations were for the patients included in the trial. However, the results of the OMEGA trial were in line with the negative findings of two meta-analyses (BMJ 2006;332:752-60 and BMJ 2008;337:a2931) and could mark the end of omega-3 supplements being used in this clinical setting.

http://www.incirculation.net/NewsIte...tMI.aspx?mid=5
http://www.endocrinetoday.com/view.aspx?rid=38413

Aunque se realizó con personas que padecieron un infarto de miocardio, concluyó que:

El uso del Omega 3 como elemento beneficioso en la prevención de la ECV ha sido empleado desde hace mucho tiempo. En el reciente ACC se presentó un interesante estudio, el cual fue realizado con el fin de evaluar el beneficio de utilizar Ácidos Omega 3 en pacientes post Síndrome Coronario Agudo con y sin elevación del segmento ST (entre 3 y 14 días) con un total de 104 centros y más de 3800 pacientes.

Después de un severo análisis estadístico, los autores presentaron resultados que no mostraron beneficios para el grupo Omega 3 en prácticamente ninguno de los parámetros evaluados.

Resultados sobre el uso de Omega 3 en pacientes post IAM: