Rising Suicide Rates in Prisons Call for Enhanced Clinical Assessment

Featured Article

The Lancet Psychiatry | 2024, Vol. 1, No. 7, 536 - 544.

Article Title

Worldwide incidence of suicides in prison: a systematic review with meta-regression analyses

Authors

Adrian P Mundt- Facultad de Medicina, Universidad Diego Portales, Santiago, Chile; Department of Psychiatry and Mental Health, Hospital Clínico Universidad de Chile, Santiago, Chile

Pablo A Cifuentes-Gramajo - General Directorate of the Research System, Western University Center, University of San Carlos de Guatemala, Quetzaltenango, Guatemala

Gergő Baranyi - Centre for Research on Environment, Society and Health, University of Edinburgh, Edinburgh, UK; Centre for Longitudinal Studies, Institute of Education, University College London, London, UK

Seena Fazel- Department of Psychiatry, University of Oxford, Oxford, UK; Oxford Health NHS Foundation Trust, Oxford, UK

Abstract

Background: Suicide is a leading cause of death during imprisonment. This systematic review aimed to [synthesize] available evidence of prison suicide incidence worldwide. Methods: We systematically searched the scientific literature, data repositories, and prison system reports, supplemented by correspondence with prison administrations. We included reports on people living in prison but excluded studies in preselected groups (by age or [offense] type). Absolute numbers and incidence rates of suicide mortality per 100 000 person years by sex and country were extracted from 2000 to 2021. IQRs were used to describe the suicide incidence in different world regions. Incidence rate ratios comparing suicides of people living in prison with [age-standardized] general populations were calculated. We conducted meta-regression analyses on national-level and prison-level factors to examine heterogeneity. The study protocol was pre-registered with PROSPERO, CRD42021296819. Findings: We included three scientific studies, 124 official reports, and 11 datasets from email correspondence. Between 2000 and 2021, there were 29 711 reported suicides during 91·2 million person-years of imprisonment in 82 jurisdictions worldwide (sex-specific data available for 13 289 individuals: 12 544 [94·4%] male and 745 [5·6%] female individuals). There were large variations between countries, with most studies reporting suicide rates in the range of 24–89 per 100,000 person-years in both sexes (22–86 in male individuals and 25–107 in female individuals). In meta-regression analyses, Europe (vs. other regions), high-income countries (vs. low-income and middle-income countries), and countries with lower incarceration rates (vs. those with higher incarceration rates) had higher suicide rates. Incidence rate ratios between people who are incarcerated and [age-standardized] general populations in the same jurisdictions were typically in the range of 1·9–6·0 in male and 10·4–32·4 in female individuals. Interpretation: Prison services worldwide, and particularly in Europe, should [prioritize] suicide prevention. Assessment and management of suicide risk in female individuals living in prison need particular attention due to excess mortality relative to community-based populations. Interpretation of [synthesized] data needs to be done with caution due to high heterogeneity between jurisdictions.

Keywords

Suicide; Incidence rate ratios; suicide prevention; suicide risk assessment; prisons

Summary of Research

"...Suicides are a leading cause of death among people living in prison… approximately one in ten people make at least one suicide attempt during their prison term. Individual and institutional risk factors for prison suicide have been identified, which include modifiable clinical factors single-cell occupancy, and a lack of social visits…

Suicide incidence data can inform policy and treatment, and can be used to monitor outcomes of prevention initiatives…. The primary aim of this study was to systematically review the evidence on suicide incidence in prisons worldwide. Secondary objectives were to describe differences in suicide incidence by prison and country characteristics, which can contribute to suicide prevention, policy measures, and service development for people living in prison" (p. 536).

"Observational studies reporting suicide incidence in general prison populations were examined. We included studies, suicide registries, reports, and datasets published or provided by prison administrations, from all jurisdictions internationally and in any language. We excluded studies that examined suicide attempts or other suicidal or self-harm [behaviors] and those that reported suicide incidence in any limited non-representative age groups or otherwise selected populations ([e.g.], violent [offenses] or ethnic minority status), as preselected subgroups might differ substantially in suicide risk from the general prison population… Using a predefined template, PAC-G extracted the data from included studies, registries, and reports. GB replicated 20% of the data extraction to ascertain quality. Variables were the study period (from 2000 to 2021), annual numbers of suicides, number of people living in prison for corresponding years, country, jurisdiction, and sex (male, female, all)" (p. 537).

"Using random-effects meta-analyses, the worldwide suicide incidence in prisons, pooled from 68 jurisdictions with at least five events, was 50 (95% CI 42–60; I²>99%) per 100 000 person-years of imprisonment. For the jurisdictions with sex-specific information and at least five cases for a specific sex, the pooled rates were 49 (40–60; 99%) per 100 000 person-years of imprisonment in male and 59 (39–82; 97%) in female individuals, with largely overlapping CIs (appendix pp 25–27). There was no clear difference in suicide rates between male and female populations in prison. Given the very high heterogeneity between jurisdictions, descriptive statistics were preferred to represent the data. Prison suicide incidence ranged from 3 per 100 000 person-years in the Philippines to 204 per 100 000 person-years in Luxembourg. The IQR for suicide incidence worldwide was 22–86 for male and 25–107 for female individuals in prison…

We found substantial heterogeneity between country groups, with Africa (three included countries; p<0·0001), the Americas (p<0·0001), and Asia (p=0·0002) having lower incidence than Europe. Due to high heterogeneity within regions, those findings need to be interpreted with caution" (p. 540).

"In this systematic review of 29 711 suicides in 82 jurisdictions from 2000 to 2021… prison suicide rates were typically more than 10 times higher in the female population and twice as high in the male population relative to the age [standardized] general population" (p. 541).

"This study has various limitations. The registries typically did not inform on the age of the suicide deaths. People living in prison and people living in the community have different age structures; however, this might not explain the large differences in suicide incidence. We did not have any information on the average length of prison sentences and turnover rates. Other limitations include that some countries might disproportionately misclassify suicides, and that the very high heterogeneity limits confidence in the pooled data…

This investigation allows public health and prison services in different countries to compare their national prison suicide rates with other jurisdictions separately in male and female prison populations. The study also allows for comparisons of national prison suicide rates with community-based people. The implementation of effective suicide prevention interventions needs to be informed by updated and consistently reported national incidence rates, between-country and regional comparisons. This report also identified institutional-level and national-level associations with prison suicide incidence, such as incarceration rate, occupancy level, and income group of the jurisdiction. Substantial regional differences in prison suicide incidence were found" (p. 543).

Translating Research into Practice

Implications:
"We found that higher occupancy ([i.e.], overcrowding) was associated with lower suicide incidence in between country analyses. Although solitary confinement can be reduced, overcrowding in prison could be linked to other poor outcomes, such as infectious disease outbreaks and self-harm" (p. 543).

"In summary, countries with high suicide rates in prison should review their assessment and prevention of suicide risk, and prioritise evidence-based initiatives across the criminal justice system" (p. 543).

Considerations:
"International comparisons might facilitate efforts to understand and implement more effective prevention" (p. 541).

"...Relative risks of drug use, posttraumatic stress disorder, and personality disorders are higher in the incarcerated female population (compared with the general female population) than the corresponding comparison in male individuals. This difference is related to the high threshold for female individuals to be imprisoned, which means that those entering prison are more selected than male individuals entering prison. This selection effect is associated with suicide risk, and it might include the seriousness of the index [offense] or charged [offense], and the number of life events associated with being in prison (such as separation from children)...." (p. 543).

Recommendations:
"Suicide prevention could involve addressing modifiable risk factors on an institutional level, such as appropriate single-cell use and removing access to means ([e.g.], taking away ligature points or periodically checking for medication hoarding). In addition, individual-level measures, including assessing and treating mental illness, need review and adequate resourcing" (p. 541- 542).

"Diversion of people with severe mental illness from criminal justice to mental health and addiction services should be part of any comprehensive approach. Countries and jurisdictions with very high suicide rates ([i.e.], above 100 per 100 000 person-years of imprisonment) could prioritize criminal justice-related and public health initiatives to reduce rates" (p. 542).

Other Interesting Tidbits for Researchers and Clinicians

Misclassification of Deaths:
"A relevant risk of bias could be related to the miscoding of suicides as other or unknown causes of death" (p. 542).

"...Suicide remains heavily [stigmatized], which would increase the likelihood of coding self-inflicted deaths as accidents or from natural causes ([e.g.], cardiovascular or respiratory if ligature involved or overdose), or more deaths classified as unknown cause or awaiting classification due to less capacity for investigation" (p. 543).

Research Gaps:
"Future research on near lethal suicide attempts and using the psychological autopsy approach could inform the contribution of mental illnesses underlying prison suicides, since such data are unavailable in suicide registries" (p. 543).

"To promote research and prevention implementation, [standardized] registries and timely publication of prison suicide data are essential" (p. 544).