By Steven Reinberg and Ernie Mundell HealthDay reporters
MONDAY, November 16, 2020 (HealthDay News) – Does highly concentrated fish oil help the heart or not?
Previous research on a prescription fish medicine called Vascepa, announced earlier this year, suggested it could be of real value for heart patients.
But the results of a study of another such drug called Epanova, released on Sunday, are disappointing: researchers found no benefit from taking the drug for a variety of heart health outcomes compared to taking a placebo pill that contains only corn oil .
“Many people continue to take fish oil supplements to help prevent heart disease [new] Study was not effective for this purpose, “said co-researcher Dr. A. Michael Lincoff in an American Heart Association press release.
He is vice chairman of research in the cardiovascular medicine division of the Heart, Vascular and Thoracic Institute at the Cleveland Clinic.
The research was presented on Sunday at the AHA’s annual virtual meeting. It was also published concurrently in the Journal of the American Medical Association.
The new study was funded by AstraZeneca, which makes Epanova. AstraZeneca announced on Friday that the Phase III trial would be halted due to disappointing results.
The conflicting results of studies of the two different prescription drugs, Vascepa and Epanova, create confusion as to whether or not heart patients really benefit from the nutrient.
“The question of whether omega-3s improve health is important for patients, doctors and the healthcare system,” noted Dr. Gregory Curfman, who wrote an editorial on the study. “Even in the COVID-19 era, cardiovascular diseases are the leading cause of death in the USA”
“Given the current uncertain state of knowledge, neither patients nor doctors can trust that omega-3 fatty acids have any health benefits,” he said.
That probably won’t stop Americans from buying the supplements: “In 2019 the world market for omega-3 fatty acids reached $ 4.1 billion and is expected to double by 2025,” said Curfman.
The new study focused on Epanova, which contains a combination of two omega-3 carboxylic acids – eicosapentaenoic acid [EPA] and docosahexaenoic acid [DHA].
More than 13,000 patients treated at centers around the world were given either Epanova or a placebo pill with corn oil. All patients had conditions that put them at “high cardiovascular risk”. For example, they were treated with cholesterol-lowering statins and either had blockages in the coronary arteries or arteries in the brain or legs, or were at risk for heart disease due to conditions such as diabetes or lifestyle risk factors such as smoking.
The study began in 2014. The study ended in January 2020, said Lincoff’s group.
During this period, over 1,600 patients suffered some type of cardiac event. But using Epanova did not reduce deaths from heart disease, heart attacks, strokes, the need for stents or bypass surgery, or hospitalization for angina.
The treatment even had a downside: researchers say the use of the prescription fish oil appeared to be linked to an increase in the risk of the common heart rhythm disorder called atrial fibrillation.
But if Epanova doesn’t seem to be of any benefit, why did heart patients who were given another prescription omega-3 drug, Vascepa, seem to have had a health boost?
According to Curfman, the answer could be in experimental design.
Vascepa contains a form of purified EPA known as icosapentethyl. The clinical study that appeared to confirm the effectiveness of Vascepa lasted 5 years. The researchers found that when compared to placebo – in this case mineral oil – taking the drug was linked to a 25 percent reduction in a variety of heart events.
“Why did these two high-quality clinical studies, both of which used the same high dose of omega-3 fatty acids, come up with conflicting results?” Asked Curfman.
Choosing the placebo – mineral oil or corn oil – could help explain the discrepancy, he said. Perhaps Vascepa “did not reduce the risk of cardiovascular events, but instead the comparator mineral oil increased the risk of cardiovascular events,” Curfman theorized. That could create the illusion that Vascepa helped patients, he reflected.
There is some evidence that mineral oil can increase LDL cholesterol levels, Curfman noted.
But at the moment, the theory that the choice of placebo influenced the results of the Vascepa study has not been tested, he said.
“Only a new clinical trial of icosapentethyl versus corn oil would definitely answer the question, but it’s unlikely that private industry will do that,” said Curfman.
Therefore, he added, “the FDA should require a post-marketing clinical trial of high-dose icosapentethyl versus corn oil in patients at risk for cardiovascular events.”
There is more on the benefits of fish oil supplements at the American Heart Association.
SOURCE: American Heart Association Annual Meeting, press release, Nov. 15, 2020; Journal of the American Medical Association, November 15, 2020