Serotonin2A receptor binding potential in people with aggressive and violent behaviour.

OBJECTIVE: Indexes of brain serotonin2A (5-HT2A) density have never been investigated in a sample of humans with violent aggressive behaviour unbiased by medication use or current axis I psychiatric disorders. The objective of this study was to investigate prefrontal cortex 5-HT2A binding potential (BPND), an index of 5-HT2A density, in an unbiased sample of people with violent aggressive behaviour. METHODS: We used [18F] setoperone positron emission tomography to measure 5-HT2A BPND in the dorsolateral prefrontal cortex (primarily sampling Brodmann area 9) in 16 participants with violent aggressive behaviour and 16 healthy control participants. RESULTS: In people with violent aggressive behaviours, the slope of 5-HT2A BPND decline in the dorsolateral prefrontal cortex is 44% less than in healthy control participants (analysis of variance group by age interaction, p = 0.004). Prefrontal cortex 5-HT2A BPND was significantly lower in participants with more severe impulsivity and aggression (multiple linear regression with age and Barratt Impulsivity Scale [BIS] as predictor variables and regional 5-HT2A BPND as dependent variable; effect of BIS, dorsolateral prefrontal cortex: F1,13 = 7.95, p = 0.014). CONCLUSION: Lower prefrontal 5-HT2A BPND is related to violent aggression. Lower 5-HT2A BPND occurs at a younger age, when violent behaviour is more frequent, and is more prominent when impulsivity and aggression are more severe.