A man examining the label on a bottle of medication. Share on Pinterest
Beta-blockers may not help reduce additional cardiovascular health risks for people after they’ve had a heart attack. grandriver/Getty Images
  • A new study has found that taking beta-blockers after a heart attack may not reduce additional cardiovascular health risks.
  • The study found that beta-blockers made no difference in improving cardiovascular risks beyond a year following a heart attack.
  • The data also showed that long-term treatment with beta-blockers wasn’t associated with improved cardiovascular outcomes during an average monitoring period of 4.5 years.

People with high blood pressure are sometimes treated with beta-blockers in cases where other medications have not worked.

Also known as beta-adrenergic blocking agents, beta-blockers work by blocking the effects of the hormone epinephrine, a.k.a. adrenaline.

Beta-blockers are also widely used to lessen the risk of further heart attacks or death.

However, a large new study published in Heart, an international peer-reviewed journal that keeps cardiologists up to date with research advances in cardiovascular disease, suggests that this is not warranted in patients who don’t have heart failure.

In the study, researchers in Sweden found no difference in the risks between patients taking beta-blockers more than a year after their heart attack and those who weren’t on these drugs.

In fact, evidence in this study suggests that beta-blocker treatment beyond one year of heart incidents for patients without heart failure was not associated with improved cardiovascular outcomes.

The real-time data also showed that long-term treatment with beta-blockers wasn’t associated with improved cardiovascular outcomes during an average monitoring period of 4.5 years.

Evidence from this nationwide study suggests that beta-blocker treatment beyond one year of myocardial infarction (MI) for patients without heart failure or left ventricular systolic dysfunction (LVSD) was not associated with improved cardio outcomes.

“It is an eye-opening study,” said the research team’s lead scientist, Gorav Batra, MD, from the Department of Medical Sciences, Cardiology, Uppsala University, Uppsala, Sweden. “People have been taking Beta Blockers for decades,” he said. “The problem is that care has changed a lot in the last decade. Our heart attack patients are not the same as they were 30 years back.”

Most of the current evidence is based on the results of clinical trials that predate major changes to the routine care of heart attack patients, Batra told Healthline.

“But because it is just an observational study, we cannot act on it. We need randomized trials. And we do have a randomized study that we expect to be completed next year,” he said.

Professor Ralph Stewart and Dr. Tom Evans, of Green Lane Cardiovascular Services, Auckland, New Zealand (Aotearoa), stated in a linked editorial on the study that “[This] study raises an important question directly relevant to the quality of care—do patients with a normal [functioning heart] benefit from long term beta-blocker therapy after [heart attack]? To answer this question, more evidence from large randomized clinical trials is needed.”

The researchers looked at 43,618 adults who had had a heart attack between 2005 and 2016 that required hospital treatment, and whose details had been entered into the national Swedish register for coronary heart disease (SWEDEHEART).

None of the people had heart failure or left ventricular systolic dysfunction (LVSD), a common and serious complication of myocardial infarction that leads to greatly increased risks of sudden death and heart failure.

Of the participants in the study, 34,253 of them were prescribed beta-blockers and were still taking them 1 year after hospital discharge, while 9,365 hadn’t been prescribed these drugs.

Their average age was 64 and around 1 in 4 were women.

The researchers were looking to see if there were any differences between the two groups in terms of deaths from any cause and rates of further heart attacks, revascularization (a procedure to restore blood flow to parts of the heart), or hospital admission for heart failure.

Some 6,475 (19%) of those on beta blockers, and 2,028 (22%) of those who weren’t on the medication, died from various causes, had another heart attack, required unscheduled revascularisation, or were admitted to the hospital for heart failure.

And after accounting for potentially influential factors, including demographics and relevant co-existing conditions, there was no discernible difference in the rates of these events between the two groups.

Elizabeth Klodas, MD, FACC, is a preventative cardiologist and founder of Step One Foods, a food company she created for her cardio patients.

She tells Healthline that she agrees with Batra and that the new research highlights the need for healthcare professionals to approach cardio care differently than they have in the past.

“Care has changed substantially over the last several decades,” Klodas tells Healthline. “I question why we still do it this way. Our goal is to do no harm, to achieve the best health for our patients, and that is not necessarily found in a bottle in your medicine cabinet.”