Drugs used to treat high blood pressure, angina and migraines could be linked to lower rates of violence, new research has suggested.
The study found there was a reduction in violence among people using Beta adrenergic-blocking agents (beta blockers) when they were on the medication, compared to when they were not taking it.
Scientists say that if the findings are confirmed by other studies, beta blockers – which work mainly by slowing down the heart – could be considered as a way to manage aggression and hostility in people with psychiatric conditions.
The medication is often used for anxiety and has been suggested for clinical depression and aggression, but the evidence is conflicting.
It has also been linked to an increased risk of suicidal behaviour, though evidence is inconclusive.
Seena Fazel, of the University of Oxford, and colleagues at the Karolinska Institute in Sweden looked at hospital admissions for psychiatric disorders, suicidal behaviour and deaths from suicide, and charges of violent crime.
They looked at 1.4 million beta blocker users in Sweden, comparing when they were and were not taking the medication over an eight-year period (2006-2013).
According to the research, periods on beta blocker treatment were associated with a 13% lower risk of being charged with a violent crime by the police, which remained consistent across the analyses.
Additionally, there was an 8% lower risk of hospital admission due to a psychiatric disorder as well as an 8% increased association of being treated for suicidal behaviour.
However, researchers say these associations varied depending on psychiatric diagnosis, past psychiatric problems, as well as the severity and type of the cardiac condition the beta blockers were being used to treat.
Prof Fazel said: “In a real-world study of 1.4 million persons, beta blockers were associated with reduced violent criminal charges in individuals with psychiatric disorders.
“Repurposing their use to manage aggression and violence could improve patient outcomes.”
Researchers say previous research has linked severe cardiac events to an increased risk of depression and suicide.
They add that these results might suggest the psychological distress and other disabilities associated with serious cardiac problems, rather than the beta blocker treatment, increases the risk of serious psychiatric events.
The findings are published in the journal PLOS Medicine.
The nature of the observational study mean it is not known whether the decreased risk of violent crime is due to beta blockers or to other factors that the authors could not take into account.