Beta Blockers Associated With Decreased Violence

The use of beta blockers, a common class of blood pressure medication, may be associated with reductions in violence, a study in PLOS Medicine suggests.

“As a psychiatrist, I noticed an inconsistent use of beta blockers for various indications, including in people who were aggressive, hostile, and at elevated risk of perpetrating violence toward others. So we did a literature review and noticed a few small, randomized, controlled trials that suggested some promising findings for violence prevention, and we wanted to follow this up,” senior author Seena Fazel, M.D., M.B.Ch.B., told Psychiatric News. He is a professor of forensic psychiatry and a Wellcome Trust Senior Research Fellow in Clinical Science at the University of Oxford, and an honorary consultant forensic psychiatrist at Oxford Health National Health Service Foundation Trust.

Fazel and colleagues analyzed data from more than 1.4 million people aged 15 years and older in Sweden’s national health care, mortality, and crime registers who had beta blocker prescriptions. The researchers followed the study population from 2006 through 2013, collecting data on whether the individuals filled their beta blocker prescriptions, had records of hospitalizations for psychiatric disorders other than self-injury or suicide attempts, had records of suicidal behaviors or died by suicide, or had charges of violent crime. The beta blockers included in the study were atenolol, bisoprolol, carvedilol, labetalol, metoprolol, pindolol, propranolol, and sotalol.

“Repurposing common medications used for physical health conditions has been an area of interest in mental health as the pipeline for new psychotropic medications has been slow in the last decade, and some large pharmaceutical companies have stopped their R&D programs in mental health. Thus we were interested in whether there were associations [between beta blocker use and] common psychiatric conditions, such as depression and anxiety,” Fazel explained.

The researchers used a within-individual study design wherein they compared outcomes during times when the individuals were taking beta blockers with the same outcomes during times when the individuals were not taking beta blockers.

Periods on beta blocker treatment were associated with a 13% lower risk of being charged with a violent crime by the police. The researchers offered several possible explanations for this, including mild sedation or reduced adrenergic activity that ultimately results in decreased reactions such as “fight or flight” in response to stressful situations.

Periods on beta blocker treatment were associated with an 8% lower risk of being hospitalized because of a psychiatric disorder. However, in a secondary analysis that separated the risks of hospitalizations for psychotic, depressive, and anxiety disorders, the results were more nuanced: The researchers found reduced risk for psychotic and depressive disorders during beta blocker treatment periods, but not for hospitalizations for anxiety disorder—a condition for which beta blockers are often prescribed off label.

Although the findings do not support beta blockers as a treatment for anxiety, Fazel said he would not consider deprescribing them in patients who take them for that purpose.

“The findings need to be considered in light of trial evidence, as well as alternatives, their availability and suitability, and individual preferences,” Fazel said. “One caveat is that we examined hospital admissions for anxiety disorders, so our findings are not necessarily generalizable to anxiety, which is less severe.”

Periods on beta blocker treatment were associated with an 8% increased risk of being treated for suicidal behavior or dying by suicide. However, the increased risk occurred in people who had a history of psychiatric hospitalizations or suicidal behavior, and overall, their risk of suicidal behaviors or dying by suicide was 0.7%. The researchers wrote that people who have a history of psychiatric problems may be at risk of suicidal behaviors or dying by suicide when they experience a cardiac condition or event because cardiac conditions and events themselves are associated with an increased risk of dying by suicide.

This study was supported by the Wellcome Trust, the Swedish Research Council for Health Working Life and Welfare, the American Foundation for Suicide Prevention, and the Karolinska Institutet. ■