Published: 08-05-2014 09:49 | Updated: 08-05-2014 09:50

Antipsychotics associated with reduced rate of violent crime

People who use antipsychotic medication to treat psychiatric illness are nearly half as likely to commit a violent crime compared to when they are not using such medication, according to a new study by researchers at Karolinska Institutet and the University of Oxford. The use of mood stabilising drugs is also associated with a reduced rate of violent crime. The findings are published in The Lancet.

Antipsychotic medication (such as clozapine or risperidone) and mood stabilising medication (such as lithium or carbamazepine) are used to treat a variety of disorders, but are most commonly associated with the treatment of schizophrenia, bipolar disorder, and related disorders that affect up to 2% of the general population. Although evidence suggests that people who use these medications are at less risk of relapse and re-hospitalisation for their illness, there has been very little evidence for these drugs' effects on real-world adverse outcomes, such as reducing violent behaviour, despite increasing prescription rates in many countries.

In the current study, researchers used Swedish national health registries to study the psychiatric diagnoses, and any subsequent criminal convictions, in over 80,000 patients (40,937 men and 41,710 women) who were prescribed antipsychotic or mood stabilising medication, from 2006 to 2009. In the four years studied between 2006 and 2009, 6.5% (2657) of the men, and 1.4% (604) of women were convicted of a violent crime. Compared with periods when participants were not on medication, violent crime fell by 45% in patients receiving antipsychotics, and by 24% in patients prescribed mood stabilisers.

The study was funded by The Wellcome Trust, the Swedish Prison and Probation Service, the Swedish Research Council, and the Swedish Research Council for Health, Working Life and Welfare.

Publication

Antipsychotics, mood stabilisers, and risk of violent crime
Seena Fazel, Johan Zetterqvist, Henrik Larsson, Niklas Långström, Paul Lichtenstein
The Lancet, online 8 May 2014, http://dx.doi.org/10.1016/S0140-6736(14)60379-2