Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Fish oil does not lower risk of heart problems for patients with implantable defibrillators

15.06.2005


Even though previous research has shown that fatty acids from fish oil reduce the risk of sudden cardiac death, patients with implantable defibrillators who took fish oil supplements did not see a reduction in serious heart rhythm abnormalities, according to a study in the June 15 issue of JAMA.



Since the original observations that Greenland Eskimos eating a diet high in omega-3 polyunsaturated fats (PUFAs) from sea mammals and fish had an unexpectedly low risk of cardiac death, multiple lines of evidence have suggested that omega-3 PUFAs have antiarrhythmic properties, according to background information in the article. Several clinical trials have shown that dietary changes or supplements to increase omega-3 PUFA intake result in a reduced risk of sudden death without a consistent change in risk of heart attack.

Merritt H. Raitt, M.D., of Oregon Health and Science University and the Portland VA Medical Center, Portland, Ore., and colleagues conducted a study to determine if fish oil supplements would have antiarrhythmic properties in patients with a recent episode of sustained ventricular arrhythmia. The double-blind, placebo-controlled trial was performed at 6 U.S. medical centers with enrollment from February 1999 until January 2003. The study included 200 patients with an implantable cardioverter defibrillator (ICD) and a recent episode of sustained ventricular tachycardia (VT) or ventricular fibrillation (VF). Patients were randomly assigned to receive fish oil, 1.8 g/d, 72 percent omega-3 PUFAs, or placebo and were followed up for a median of 718 days.


The researchers found that at 6, 12, and 24 months, 46 percent, 51 percent, and 65 percent of patients randomized to receive fish oil had ICD therapy for VT/VF compared with 36 percent, 41 percent, and 59 percent for patients randomized to receive placebo. In the subset of 133 patients whose qualifying arrhythmia was VT, 61 percent, 66 percent, and 79 percent of patients in the fish oil group had VT/VF at 6, 12, and 24 months compared with 37 percent, 43 percent, and 65 percent of patients in the control group. Recurrent VT/VF events were more common in patients randomized to receive fish oil.

"This study was undertaken to better understand the previously observed reduction in sudden death mortality after myocardial infarction associated with fish oil supplementation. The fact that we were not able to demonstrate an antiarrhythmic effect of fish oil does not call into question the potential benefits of fish oil or dietary fish intake in patients who have had a myocardial infarction. Instead, our results suggest that the mechanism of benefit, if due to antiarrhythmic properties, may not be due to the suppression of reentrant VT or VF. The lack of benefit and the suggestion that fish oil supplementation may increase the risk of VT or VF in some patients with ICDs can reasonably be interpreted as evidence that the routine use of fish oil supplementation in patients with ICDs and recurrent ventricular arrhythmias should be avoided," the authors conclude.

Christine Pashley | EurekAlert!
Further information:
http://www.jamamedia.org

More articles from Studies and Analyses:

nachricht New study: How does Europe become a leading player for software and IT services?
03.04.2017 | Fraunhofer-Institut für System- und Innovationsforschung (ISI)

nachricht Reusable carbon nanotubes could be the water filter of the future, says RIT study
30.03.2017 | Rochester Institute of Technology

All articles from Studies and Analyses >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Can the immune system be boosted against Staphylococcus aureus by delivery of messenger RNA?

Staphylococcus aureus is a feared pathogen (MRSA, multi-resistant S. aureus) due to frequent resistances against many antibiotics, especially in hospital infections. Researchers at the Paul-Ehrlich-Institut have identified immunological processes that prevent a successful immune response directed against the pathogenic agent. The delivery of bacterial proteins with RNA adjuvant or messenger RNA (mRNA) into immune cells allows the re-direction of the immune response towards an active defense against S. aureus. This could be of significant importance for the development of an effective vaccine. PLOS Pathogens has published these research results online on 25 May 2017.

Staphylococcus aureus (S. aureus) is a bacterium that colonizes by far more than half of the skin and the mucosa of adults, usually without causing infections....

Im Focus: A quantum walk of photons

Physicists from the University of Würzburg are capable of generating identical looking single light particles at the push of a button. Two new studies now demonstrate the potential this method holds.

The quantum computer has fuelled the imagination of scientists for decades: It is based on fundamentally different phenomena than a conventional computer....

Im Focus: Turmoil in sluggish electrons’ existence

An international team of physicists has monitored the scattering behaviour of electrons in a non-conducting material in real-time. Their insights could be beneficial for radiotherapy.

We can refer to electrons in non-conducting materials as ‘sluggish’. Typically, they remain fixed in a location, deep inside an atomic composite. It is hence...

Im Focus: Wafer-thin Magnetic Materials Developed for Future Quantum Technologies

Two-dimensional magnetic structures are regarded as a promising material for new types of data storage, since the magnetic properties of individual molecular building blocks can be investigated and modified. For the first time, researchers have now produced a wafer-thin ferrimagnet, in which molecules with different magnetic centers arrange themselves on a gold surface to form a checkerboard pattern. Scientists at the Swiss Nanoscience Institute at the University of Basel and the Paul Scherrer Institute published their findings in the journal Nature Communications.

Ferrimagnets are composed of two centers which are magnetized at different strengths and point in opposing directions. Two-dimensional, quasi-flat ferrimagnets...

Im Focus: World's thinnest hologram paves path to new 3-D world

Nano-hologram paves way for integration of 3-D holography into everyday electronics

An Australian-Chinese research team has created the world's thinnest hologram, paving the way towards the integration of 3D holography into everyday...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Marine Conservation: IASS Contributes to UN Ocean Conference in New York on 5-9 June

24.05.2017 | Event News

AWK Aachen Machine Tool Colloquium 2017: Internet of Production for Agile Enterprises

23.05.2017 | Event News

Dortmund MST Conference presents Individualized Healthcare Solutions with micro and nanotechnology

22.05.2017 | Event News

 
Latest News

How herpesviruses win the footrace against the immune system

26.05.2017 | Life Sciences

Water forms 'spine of hydration' around DNA, group finds

26.05.2017 | Life Sciences

First Juno science results supported by University of Leicester's Jupiter 'forecast'

26.05.2017 | Physics and Astronomy

VideoLinks
B2B-VideoLinks
More VideoLinks >>>