As of 2018, there were over 11 million people imprisoned globally. Suicide and self-harm rates have been found to be markedly elevated among imprisoned individuals, however there is much less literature reporting on risk factors for suicide and self-harm following prison release. The immediate post-release period has been found to be a particularly high-risk period for suicide and self-harm. Since many more people are released into the community every year than people kept imprisoned, released prisoners' health is a matter of public health concern. With the societal impact of this topic in mind, this systematic review aims to collate the risk factors for suicide and self-harm upon release from prison.

PubMed, PsycINFO, MEDLINE, and Cochrane were systematically searched using keywords relating to prison release, self-harm and suicide for articles published since 1/1/12. Studies were included if they reported data on risk factors for self-harm or suicide and followed prespecified inclusion criteria. Articles were screened by the author and uncertainty was settled by two independent reviewers. Included studies were evaluated using standardised quality assessment tools. Quantitative data were narratively synthesised due to a high level of heterogeneity in between studies.

248 articles were identified in total. 10 articles were included, reporting data on self-harm and suicide risk factors from 5 countries. Studies ranged from moderate (n = 2) to high quality (n = 8). Risk factors were categorised into the following: demographic characteristics, psychiatric history, conviction type, and imprisonment history. Risk factors which did not fit into any of these categories were categorised into an ”other” group. It was found that there were many non-modifiable factors such as violent convictions, female sex, Indigenous (Torres Strait Islander or Aboriginal) ethnicity, and single relationship status which increase self-harm or suicide risk upon release.

To our knowledge, this is the first systematic review to collate the risk factors for suicide and self-harm following prison release. The results show a complex variety of risk factors. The high mortality rate in this group necessitates the need for strategies to intervene before community re-entry. Study into risk factors post-release may guide identification of at-risk groups to target with proactive, coordinated care pre- and post-release. It is likely this will require a multifactorial approach including health, social and community programmes.