New therapy reduces reoffending in male offenders with antisocial personality disorder

A new psychological therapy designed by a team of UCL-led researchers has been found to reduce rates of violence and aggression among male offenders with antisocial personality disorder (ASPD).

The study, published in The Lancet Psychiatry and funded by the National Institute for Health and Care Research (NIHR), investigated whether aggression and antisocial behaviours could be improved by a modified form of mentalisation-based treatment (MBT).

Mentalisation-based treatment is a type of therapy that helps people to understand their own thoughts and feelings, as well as those of others. 

The new treatment, known as MBT-ASPD, aims to enhance the ability of male offenders with ASPD to recognise and reflect on both their own and others' thoughts and feelings, helping to improve interpersonal interactions and decision-making.

Antisocial Personality Disorder is a mental health condition characterised by a persistent pattern of disregarding or violating the rights of others. Symptoms include deceitfulness, impulsivity, aggression, recklessness and a lack of remorse. It frequently involves criminality.

For the largest study of its kind, 157 male offenders on probation with ASPD in England and Wales received a 12-month course of MBT-ASPD alongside standard probation services. A control group of 156 participants received probation services without MBT-ASPD.

The treatment involved weekly 75-minute group therapy sessions led by two trained MBT clinicians, often supported by an expert by experience. The group enabled participants to explore social interactions including their personal values, observe how others thought about issues that concerned them, how their actions were seen by others and how their perceptions of themselves corresponded to others’ perceptions of them.

Participants also received monthly 50-minute individual therapy sessions. These sessions focused on developing mentalising skills (such as self-awareness, empathy for others, perspective taking and reflective thinking), particularly in situations of interpersonal conflict.

The results revealed that men who received MBT-ASPD had aggression levels approximately 50% lower than those in the standard probation services.  

While both groups showed a decrease in ASPD symptoms, the MBT-ASPD group showed a significantly greater decrease of 63% in the number of symptoms at the 12 months follow-up.

Additionally, men in the MBT-ASPD group committed 46% fewer offences than those in the standard probation group over a three-year follow-up period.

Chief Investigator Professor Peter Fonagy (UCL Psychology & Language Sciences) said: “Given the enormous personal and societal costs of antisocial personality disorder – including higher risk-taking, poorer health outcomes, reduced employment, and an estimated £16.7 billion annual economic burden in the UK – this study represents a major breakthrough.

“Antisocial personality disorder has historically been difficult to treat, but our findings demonstrate that a psychological intervention requiring relatively limited therapist training can meaningfully improve outcomes for individuals with this condition while also reducing their impact on society.”

Despite previous mixed results from other psychological treatments such as Cognitive Behavioural Therapy (CBT), MBT-ASPD offers a promising new approach for male offenders. The study provides some of the strongest evidence to date that structured therapy can be effective in reducing aggression and criminal behaviours among individuals with ASPD.

Co-author and lead clinician Professor Anthony Bateman (UCL Psychology & Language Sciences) said: “This study suggests that clinicians can now be more optimistic about treating individuals with antisocial traits, who are often seen as untreatable and consequently face barriers in accessing both physical and mental health care.”

Encouraged by these findings, the research team is now calling for further studies to determine whether MBT-ASPD could be beneficial for a wider range of individuals, including those involved in serious violent behaviour, such as intimate partner violence.

Co-author Dr Elizabeth Allison (UCL Psychology & Language Sciences) said: “Traditional justice methods, such as imprisonment, have not been effective in reducing reoffending in cases of domestic abuse. Future research should explore how MBT-ASPD can be adapted for individuals involved in severe violence.

“Additionally, we need to assess how variations in treatment intensity and duration influence outcomes and whether the benefits of therapy are sustained over time.”

The study was carried out in collaboration with researchers at Anna Freud, Newcastle University, King’s College London, Royal Holloway, the National Probation Service London Division, University of Prince Edward Island, Bangor University, University of Nottingham and Imperial College London.

Study limitations

While the results are promising, the study had some limitations. The design made it challenging to isolate the specific effects of MBT-ASPD from the additional attention participants received.

Data collection issues and missing data – exacerbated by COVID-19-related delays – may also have impacted the findings.

Furthermore, since the study focused on male offenders aged 21 and older under probation supervision, the results may not be directly generalisable to other populations, such as younger offenders or those outside the probation system.