There is a risk associated with severe mental health problems and subsequent criminals for violent crime, and a number of reviews have concluded that a diagnosis of schizophrenia or bipolar disorder is associated with a higher risk. A previous elf blog written by Rebecca Syed has debated this risk.

However, the likelihood of being attacked by someone with severe mental health problems is often exaggerated in the media and this can fuel the stigma of illnesses such as psychosis.

What’s more, there is also evidence to suggest that this risk is falling (e.g. Homicide by mental health patients continues to fall, with latest figures at their lowest since 1997).

A recent study published in The Lancet by Dr Seena Fazel and colleagues, aimed to explore whether being prescribed an antipsychotic or mood stabiliser reduced the risk of patients committing violent crime.

Methods

The research team conducted a cohort observational study drawing on data from the Swedish national registers. A total sample of 82,647 patients were prescribed an antipsychotic or mood stabiliser. Data was collected for the period 1^st July 2005 to 30^th June 2010, although periods at the beginning and end of the timeframe were excluded. The primary outcome was conviction for a violent crime.

Results

• 6.5% of men (n=2,657) taking an antipsychotic or mood stabiliser were convicted of a violent crime
• 1.4% of women (n=604) taking an antipsychotic or mood stabiliser were convicted of a violent crime
• Violent crime fell by 45% in those taking an antipsychotic, compared to when not taking one (HR 0.55, 95% CI 0.47 to 0.64)
• Violent crime fell by 24% in those taking a mood stabiliser, compared to when not taking one (HR 0.76, 95% CI 0.62 to 0.93). However, this effect was only significant for people with a bipolar diagnosis
• High doses of antipsychotics had a greater effect, compared to low doses
• Depot medication compared to oral medication also had a greater effect (0.60, 95% CI 0.39 to 0.92)

Conclusions

The authors concluded:

In summary, in this large population-wide study, we recorded reductions in violent crime in patients who were prescribed antipsychotics. Rates of violent crime were also reduced in patients with bipolar disorder who were receiving mood stabilisers. Therefore in addition to the effects of antipsychotics and mood stabilisers on relapse rates, their potential effects on violence and crime should also be taken into account in decisions about management for these groups of patients.

Discussion

This is the first population based report of the positive effects of antipsychotic medication and mood stabilisers on reducing the risk of a conviction for violent crime. This paper does suggest that there is potential to reduce violent crime in those with schizophrenia and bipolar disorder if they are prescribed medication. But there could be numerous other explanations for this finding, for example:

• If more compliant with medication, is someone more likely to be engaging with community mental health services and therefore getting a variety of other support?
• Does not being prescribed a medication increase risk in other ways, for example indicating intent to commit criminal activity or a worsening social situation?

It is also worth considering whether these findings generalizable to the UK, as convictions in Sweden are not related to diagnosis, as they are in other countries, and this study focused on conviction and prescription rates.

Despite these findings, the preoccupation with violent crime often overlooks the fact that individuals with mental health problems are more likely to be victims of crime than commit it. This preoccupation with violent crime contributes to considerable stigma within our society.

Links

Fazel S, Zetterqvist J, Larsson H, Långström N, Lichtenstein P. Antipsychotics, mood stabilisers, and risk of violent crime. The Lancet, 8 May 2014. DOI: 10.1016/S0140-6736(14)60379-2. [Abstract]

Syed, R. Are you really at risk of attack by someone with schizophrenia? Mental Elf, 24 June 2014.

Banksy picture appears courtesy of: 1000 Words / Shutterstock.com