Background: Suicide is a leading cause of death during imprisonment. This systematic review aimed to synthesise 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 offence 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-standardised 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-standardised 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 prioritise 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 synthesised data needs to be done with caution due to high heterogeneity between jurisdictions.
Funding: Agencia Nacional de Investigación y Desarrollo, Economic and Social Research Council, and Wellcome Trust.
The opioid crisis is an international public health concern. Treatments for opioid use disorder centre largely on the management of opioid withdrawal, an aversive collection of signs and symptoms that contribute to opioid use disorder. Whereas in the past 50 years more than 90 medications have been developed for depression, only five medications have been developed for opioid use disorder during this period. We posit that underinvestment has occurred in part due to an underdeveloped understanding of opioid withdrawal syndrome. This Personal View summarises substantial gaps in our understanding of opioid withdrawal that are likely to continue to limit major advancements in its treatment. There is no firm consensus in the field as to how withdrawal should be precisely defined; 10-550 symptoms of withdrawal can be measured on 18 scales. The imprecise understanding of withdrawal is likely to result in overestimating or underestimating the severity of an individual's withdrawal syndrome or potential therapeutic effects of different candidate medications. The severity of the opioid crisis is not remitting, and an international research agenda for the study and assessment of opioid withdrawal is necessary to support transformational changes in withdrawal management and treatment of opioid use disorder. Nine actionable targets are delineated here: develop a consensus definition of opioid withdrawal; understand withdrawal symptomatology after exposure to different opioids (particularly fentanyl); understand precipitated opioid withdrawal; understand how co-exposure of other drugs (eg, xylazine and stimulants) influences withdrawal expression; examine individual variation in withdrawal phenotypes; precisely characterise the protracted withdrawal syndrome; identify biomarkers of opioid withdrawal severity; identify predictors of opioid withdrawal severity; and understand which symptoms are most closely associated with treatment attrition or relapse. The US Food and Drug Administration recently established a formal indication for opioid withdrawal that has invigorated interest in drug development for opioid withdrawal management. Action is now needed to support these interests and help industry identify new classes of medications so that real change can be achieved for people with opioid use disorder.