Incidence of suicide and self-harm among people with opioid use disorder and the impact of opioid agonist treatment: A retrospective data linkage study

By Samantha Colledge-Frisby, Nicola Jones, Louisa Degenhardt, Matthew Hickman, Prianka Padmanathan, Thomas Santo Jr, Michael Farrell and Natasa Gisev

Published 23 March 2023


Opioids are drugs that acts on opioid receptors in the brain and are often known for their pain-relieving qualities. People who use opioids outside the bounds of medical prescription die by suicide at nearly eight times the expected rate. Evidence also suggests people with opioid use disorder are over 23 times as likely to present to hospital with self-harm compared to matched controls.

There is evidence that opioid agonist treatment with methadone or buprenorphine can reduce the risk of suicide among people with opioid use disorder. However, less is understood about how the risk of self-harm and suicide may vary throughout different stages of treatment.

This study aimed to estimate the incidence of self-harm and suicide among people with opiate use disorder and compare rates across different time periods of opioid agonist treatment.

Research and findings

The study included 45,664 individuals who undertook opioid agonist treatment in New South Wales between 2002 and 2017. Treatment time periods were defined as the first 28 days after starting, more than 29 days after starting, the first 28 days after stopping, and more than 29 days after stopping.

Researchers used statistical models to calculate the incidence of self-harm hospitalisations and suicide across the four treatment time periods. The authors observed that:

  • Staying on treatment for more than 29 days was protective against self-harm hospitalisations and suicide.
  • The first 28 days after stopping treatment was associated with increased risk of self-harm and suicide.
  • The risk of suicide was 17 times higher in the first 28 days after stopping treatment.
  • Self-harm increased after starting treatment, compared to stable treatment periods.
  • There was no increased risk of suicide in the first 28 days after starting treatment.


This study demonstrates that opioid agonist treatment may reduce suicide and self-harm risk in people with opioid use disorder. However, periods of starting and stopping treatment are critical for targeting self-harm and suicide prevention interventions.

The study was likely to capture more severe cases of self-harm requiring hospitalisation. It is also necessary to examine whether similar high-risk periods exist for community-level self-harm.

Suicide risk assessments and management, as well as safety planning, may be valuable during these periods. Further research is needed to develop effective interventions that prevent self-harm and suicide during less stable treatment periods.