Photo Credit: Marco

The following is a summary of “Mentalisation-based treatment for antisocial personality disorder in males convicted of an offence on community probation in England and Wales (Mentalization for Offending Adult Males, MOAM): a multicentre, assessor-blinded, randomised controlled trial,” published in the March 2025 issue of Lancet Psychiatry by Fonagy et al.  

Antisocial personality disorder poses significant health and social challenges, with limited evidence for effective treatments. Mentalization-based treatment (MBT) antisocial personality disorder (ASPD) helps regulate thoughts and emotions to reduce problematic behaviors.  

Researchers conducted a retrospective study to assess the clinical and cost-effectiveness of MBT-ASPD vs probation in reducing aggression over 12 months.  

They performed a Mentalization for Offending Adult Males (MOAM) trial, 2-group, assessor-masked, randomized controlled trial in England and Wales and enrolled males aged ≥21, convicted of an offence, under National Probation Service supervision, meeting DSM-5 criteria for antisocial personality disorder, and scoring ≥15 on the Overt Aggression Scale-Modified (OAS-M). The participants were screened in 3 stages and randomly allocated (1:1) them to MBT-ASPD plus probation or probation alone, stratified by site, age, probation order type, and remaining probation duration and offered the MBT-ASPD group 12 months of weekly 75-min group therapy and monthly 50-min individual sessions. The aggression was measured using the OAS-M at 12 months and analyzed the data using a linear mixed-effects model, adjusting for baseline at each follow-up (months 3, 6, 9, 12, 15, 18, 21, 24).  

The results showed that between Jan 2, 2016, and Aug 31, 2018, 1,946 individuals were referred, and 313 were randomly allocated (157 to MBT-ASPD plus probation, 156 to probation alone). The mean age was 34.2 years (SD 9.3); 247 (79%) identified as White British, Irish, or White Other, 30 (10%) as Black British, and 29 (9%) as Mixed. At 12 months, mean OAS-M scores were higher in the probation group (186 [SD 153]) than in the MBT-ASPD group (90 [SD 126]), with an adjusted mean difference of –73.5 (95% CI –113.7 to –33.2); P <0.0001, effect size 0.74 while, 7 deaths and 1 presumed death occurred, all in the probation group, none trial-related. 

Investigators found MBT-ASPD to be a promising intervention for antisocial personality disorder in a forensic population and suggested further research to assess its generalizability and long-term effects.  

Source: thelancet.com/journals/lanpsy/article/PIIS2215-0366(24)00445-0/abstract