Antipsychotics, mood stabilisers, and reductions in violence

In the past 25 years, evidence has accumulated that people with schizophrenia are at increased risk to commit violent crimes and, to a lesser degree, non-violent crimes compared with the general population.1 A smaller amount of evidence suggests that patients with bipolar disorder are also at increased risk of committing violent offences.2 Although both disorders are mainly treated with drugs that reduce risk of relapse, the effect of antipsychotic medications and mood stabilisers on violence has been unclear. In view of the human suffering, stigma, and costs resulting from violence by people with these disorders, the identification of humane and effective strategies to reduce such behaviours is an urgent unmet need.
In their study in The Lancet, Seena Fazel and colleagues3 used Swedish national registers to investigate whether prescriptions for antipsychotic drugs and mood stabilisers were associated with reductions in violent crime. During 2006—09, antipsychotics or mood stabilisers were prescribed to 40 937 men and 41 710 women in Sweden, of whom 2657 (6·5%) men and 604 (1·4%) women were convicted of a violent crime during the study period. Within-individual analyses were used to compare convictions for violent crime during periods when drugs were prescribed compared with periods when no prescriptions were dispensed. Violent crime was reduced by 45% in patients receiving antipsychotics (hazard ratio [HR] 0·55, 95% CI 0·47—0·64) and by 24% in patients prescribed mood stabilisers (0·76, 0·62—0·93). Depot medications (HR adjusted for concomitant oral drugs 0·60, 95% CI 0·39—0·92) and higher doses of antipsychotics were also associated with reductions in violent crime (p=0·019).