Patients may become unnecessarily depressed by common heart medicine

"We found that beta blockers led to slightly higher levels of depression symptoms in patients who had had a heart attack but were not suffering from heart failure. At the same time, beta blockers have no life-sustaining function for this group of patients," says Philip Leissner, a doctoral student in cardiac psychology and the study's first author.

Beta blockers are drugs that block the effects of adrenaline on the heart and have been used for decades as a basic treatment for all heart attack patients. In recent years, their importance has started to be questioned as new, successful treatments have begun to be developed. This is mainly the case for heart attack patients whose heart has a normal pumping function even after the attack, i.e. people who do not suffer from heart failure.

The researchers wanted to look at the side effects of beta blockers, that is, whether they affect anxiety and depression levels. This is because older research and clinical experience suggests that beta blockers are linked to negative side effects such as depression, difficulty sleeping and nightmares.

Earlier this year, a major national study was conducted in Sweden (DOI:10.1056/NEJMoa2401479), which found that those who received beta-blocking drugs were not protected from relapse or death compared to those who did not receive the drug. Leissner and his colleagues based their research on these findings and conducted a sub-study. It ran from 2018 to 2023 and involved 806 patients who had had a heart attack but no problems with heart failure. Half were given beta blockers and the other half were not. About 100 of the patients receiving beta blockers had been taking them since before the study, and the researchers observed more severe symptoms of depression in them.

"Most doctors used to give beta blockers even to patients without heart failure, but as the evidence in favour of doing so is no longer so strong, this should be reconsidered. We could see that some of these patients appear to be more at risk of depression. If the drug doesn't make a difference to their heart, then they are taking it unnecessarily and at risk of becoming depressed," adds Leissner.