Prisons are important public-health settings: housing an estimated 11.5 million people worldwide (Fair & Walmsley, 2024). The health needs of people in prison differ markedly from people in the general population, including higher prevalence of psychiatric disorders (Fazel et al., 2016), communicable disease (such as HIV and hepatitis) (Dolan et al., 2016), non-communicable disease (such as cancer and diabetes) (Munday et al., 2019) and a shorter life expectancy (Patterson, 2013). The experience of incarceration can be further detrimental to prisoners’ health outcomes, and length of incarceration has a direct relationship with reduction in life (Patterson, 2013).
Despite the disproportionate disease burden that people in prison experience, healthcare provision is inadequate. Prison could provide a place of stability that provides the same access and quality in healthcare provision that people in the community receive. To do this, policymakers and service leads need clear and comparable data to allocate resources and provide intervention. This recent umbrella review (a review of meta-analyses) can help by summarising the breadth of evidence across conditions (Favril et al, 2024).
People in prison are disproportionately affected by health conditions, this umbrella review summarises the health status of prisoners worldwide
Methods
Favril and colleagues conducted an umbrella review of meta-analyses reporting the prevalence or incidence of mental and physical health conditions among general prison populations worldwide. They searched five databases up to October 2023. To enhance their search, they used forward citation chaining, manually searched reference lists of relevant papers, and searched grey literature.
The authors selected one best meta-analysis per condition, and extracted pooled prevalence estimates, heterogeneity (I²), and indicators of publication bias (small-study effects and excess significance).
Quality was assessed using the ROBIS (Risk of Bias in Systematic Reviews) tool, and an overall quality assessment was assigned to each health condition ranging from 0 (low quality) to 4 (high quality). The authors summarised each condition’s evidence strength across psychiatric, infectious, and non-communicable diseases. Analyses were descriptive and stratified where possible by sex, age, and national income level.
Results
Mental health conditions
- Five meta-analyses were identified reporting on eight mental health conditions
- Overall prevalence of mental health conditions ranged from 3.7% (95% CI 3.2 to 4.1) for psychotic illness to 40.4% (31.8 to 49.0) for antisocial personality disorder
- Around one in ten people were estimated to be affected by major depression (11.4% [95% CI 9.9 to 12.8]) or PTSD (9.8% [6.8 to 13.2])
- When people were admitted to prison, 23.8% (95% CI 21.0 to 26.7) met criteria for alcohol use disorder and 38.9% for drug use disorder (95% CI 31.5 to 46.2)
- In women, borderline personality disorder affected 22.7% (95% CI 17.8 to 27.7)
- Psychotic illnesses and major depression were more prevalent in low-income and middle-income countries than high-income countries, whereas PTSD was more prevalent in high-income countries.
Physical health conditions
- Seven meta-analyses were found reporting on ten physical health conditions
- Prevalences ranged from 0.6% for epilepsy (95% CI 0.3 to 0.8) to 17.7% for hepatitis C virus (95% CI 15.0 to 20.7)
- The prevalence for other blood-borne diseases were lower. The prevalence of hepatitis B was 5.2% (95% CI 2.2 to 9.3) and 3.4% for HIV (95% CI 3.2 to 3.6)
- The prevalences of bacterial sexually transmitted infections were 8.9% for chlamydia (95% CI 8.2 to 9.7), 3·3% for gonorrhoea (95% CI 2.9 to 3.8), and 2.9% for syphilis (95% CI 2·6 to 3·2).
Age and sex differences
- Women in prison exhibited higher rates of PTSD and drug use disorder, whereas antisocial personality disorder was more frequent in men
- Non-communicable diseases were more prevalent among older prisoners (≥50 years).
Quality assessment
- ROBIS Criteria:
- 33% of the studies were rated as low risk of bias.
- 25% of the studies were rated as moderate risk of bias.
- 42% of the studies were rated as high risk of bias.
- The three most common reasons for lack of bias were absence of pre-registered study protocol, no risk-of-bias assessment, and insufficient examination of heterogeneity.
- Heterogeneity was found to be high in 94% of studies.
- Small-study effects were found in 89% of studies.
- Overall quality rating was low (rated 0.9 out of 4):
- 6 (out of 4) for physical health conditions.
- 4 (out of 4) for mental health conditions.
Anti-social personality disorder and Hepatitis C were the most prevalent mental health and physical health conditions in prisoners worldwide.
Conclusions
The findings reaffirm that people in prison bear a disproportionate burden of mental and physical health conditions. The authors correctly highlight that prevalence estimates should be interpreted with caution due to small study effects and high heterogeneity in the selected study.
Given that most incarcerated individuals return to the community, prisons represent critical sites for screening, treatment, and prevention of treatable mental and physical health conditions that influence population health far beyond the prison walls.
Prisons represent critical sites for screening, treatment, and prevention of treatable mental and physical health conditions that influence population health far beyond the prison walls.
Strengths and limitations
Strengths
- This study brings awareness to a population of people whose healthcare needs are often overlooked and highlights where service provision is needed.
- Five appropriate databases were included, and grey literature was searched. Furthermore, authors bolstered their literature search using forward citation chaining and reference lists of relevant reviews.
- The authors were very transparent with their inclusion criteria which makes replication and comparison much easier.
- Multiple quality assessments for selected studies which included prevalence estimates with confidence intervals, heterogeneity, small-study effects, risk of bias (assessed by the ROBIS tool), and an overall quality assessment.
- Health conditions were only included by clinical investigation, e.g. biological markers or clinical investigation. This helps to reduce false-positives and is a more stringent tool rather than using screening tools or patient’s notes. However, clinical investigation can be difficult to come by in prisons due to demand, staff shortages and high prison population turnover. I therefore would not be surprised if the true prevalence of the health conditions is higher than stated in this review.
Limitations
- The disadvantage to including studies across different countries is that it can reduce policymakers ability to make specific changes to their national prison systems.
- The list of countries included in the analysis was not reported. It is therefore not possible to understand if the pooled prevalence is being influenced by countries that typically conduct more research. Without an understanding of the proportion of countries that are used to calculate the prevalence, it is not possible to understand how representative of the global burden these prevalences are.
- Analysis by sex, age and country income level was proposed, but the results on this are limited most likely due to the selected studies.
- Data gaps are evident for several disorders (e.g., anxiety, bipolar disorder, neurodevelopmental conditions).
This review was conducted to a high standard; but further analysis is needed for specific recommendations.
Implications for practice
- This umbrella review implemented a rigorous methodological process to analyse data from meta-analyses researching the global burden of physical and mental health conditions in prisons. Despite the selected studies having heterogeneity (a common limitation of research in prisons), this review lends itself to an accurate representation of physical and mental health conditions in prisons. It brings much needed awareness to the pressure prisons, and their healthcare staff, can be placed under.
- Prisons represent a unique opportunity to provide physical and mental healthcare support to a population of people who have experienced health inequality. With an adequate provision of resources based on reviews such as this one, prisons could implement effective screening, tailored treatment, and connections to community follow up for the highlighted conditions.
- These findings highlighted some differences in need between male and female prisons, as well as differences between countries income level. Further research and stratified analysis into this area could provide insights that would further inform resource acquisition. This review highlighted drug use disorder was higher in the female estate and acknowledged the comorbidity that is often seen with PTSD. Policymakers could therefore use these results to provide provision for trauma therapy and substance use, as well ensuring staff feel skilled to manage the interaction of PTSD and substance use.
Prisons represent an opportunity to support people with their healthcare who have been unfairly disadvantaged.
Statement of interests
Ross Nedoma declares no conflicts of interest.
Editor
Edited by Laura Hemming
Links
Primary paper
Louis Favril, Josiah Rich, Jake Hard, Seena Fazel (2024). Mental and physical health morbidity among people in prisons: an umbrella review. The Lancet Public Health, 9(4), e250-e260.
Other references
Dolan, K., Wirtz, A. L., Moazen, B., Ndeffo-mbah, M., Galvani, A., Kinner, S. A., Courtney, R., McKee, M., Amon, J. J., Maher, L., Hellard, M., Beyrer, C., & Altice, F. L. (2016). Global burden of HIV, viral hepatitis, and tuberculosis in prisoners and detainees. The Lancet, 388(10049), 1089–1102. https://doi.org/10.1016/S0140-6736(16)30466-4
Fair, H., & Walmsley, R. (2024). World Prison Population List. fourteenth edition. 1–18.
Fazel, S., Hayes, A. J., Bartellas, K., Clerici, M., & Trestman, R. (2016). Mental health of prisoners: prevalence, adverse outcomes, and interventions. The Lancet Psychiatry, 3(9), 871–881. https://doi.org/10.1016/S2215-0366(16)30142-0
Munday, D., Leaman, J., O’Moore, É., & Plugge, E. (2019). The prevalence of non-communicable disease in older people in prison: A systematic review and meta-analysis. Age and Ageing, 48(2), 204–212. https://doi.org/10.1093/ageing/afy186
Patterson, E. J. (2013). The dose-response of time served in prison on mortality: New York State, 1989-2003. American Journal of Public Health, 103(3), 523–528. https://doi.org/10.2105/AJPH.2012.301148
