For half a century beta blockers have been used to help patients with cardiovascular problems manage their abnormal heart rhythms, but a new study tracking over a million people has found the common drug may also reduce aggression and violent behavior.
Although beta blockers were originally developed back in the 1960s as a treatment for angina, a heart condition, the drugs have since been repurposed for a number of different uses, from glaucoma to migraine. Perhaps most interesting has been the use of beta blockers for psychiatric conditions such as anxiety and PTSD.
Because beta blockers work by disrupting the activity of hormones like adrenaline and noradrenaline the drugs are thought to be useful in treating a variety of behavioral problems, but until now most research has only focused on small cohorts or anecdotal data.
Propranolol, a commonly prescribed beta blocker, has long been informally used by musicians and performers as a tool to manage stage fright. In some sports beta blockers have even been banned, classified as performance-enhancing due to their ability to reduce tremors. In 2008, a double-gold Olympic medallist was stripped of his awards for shooting after a positive drug test to beta blockers.
This new study took a big picture approach at the subject, looking at 1.4 million health records from patients treated with beta blockers. Each patient was followed for up to eight years, and the researchers focused on associations between beta blocker use and psychiatric problems, violent crime and suicidal behavior.
Interestingly, the researchers found no evidence beta blocker use is effective at reducing rates of anxiety, at least from the perspective of anxiety-related hospital admissions. However, the study did detect signs the drug could be linked to a 13% lower risk of violent crime charges.
“In a real-world study of 1.4 million persons, β-blockers were associated with reduced violent criminal charges in individuals with psychiatric disorders," said Seena Fazel, a researcher from the University of Oxford working on the study. "Repurposing their use to manage aggression and violence could improve patient outcomes.”
Susana P. Gaytán Guía, from the University of Seville, called the new study rigorous and well-balanced. According to Gaytán Guía the findings are clinically valuable and should inform future studies into potential new uses for the common heart medicines.
“It seems to me to be a very rigorous study with a very large study population, and well balanced by gender, so the prospects for future research and clinical use that it proposes should be very much taken into account," said Gaytán Guía. "Specifically, in their study of the whole population, they found no consistent links between β-blockers and psychiatric outcomes, while they did, and this seems to me very relevant, with reductions in violence. It prompts us to think about possible therapeutic avenues, proposing, therefore, that the use of β-blockers to control aggression and violence be explored further."
Exactly how beta blockers could be specifically influencing aggressive behavior is still unclear. The researchers speculate a number of potential mechanisms, from the drugs acting as mild sedatives to them suppressing adrenergic activity in stressful situations.
Ultimately, the researchers concluded more study is warranted to better understand the potential impact of these drugs on aggressive behaviors. And if further validated, the drugs could be useful in managing aggression in psychiatric patients.
The new study was published in PLOS Medicine.
Source: PLOS