[Prevalence of mental disorders in French prisons: A systematic review]

The prevalence of psychiatric disorders among prisoners remains a major public health issue worldwide. In France, despite the increasing number of persons who are incarcerated (+30% between 1992 and 2002 with a 120% prison overcrowding), and a historical concern about the mental health of persons in detention and its management, no systematic review has been published on this subject. The aim of this article is to present the results of a systematic review of the literature on the prevalence of psychiatric disorders in French prisons.

The reporting of this systematic review conforms to the PRISMA (Preferred Reporting Items for Systematic reviews and Meta-Analyses) checklist. We searched the PubMed and Web of Science databases. We used combinations of keywords relating to prison (prison*, jail*, inmate*), to psychiatry ("mental health", psychiatr*), and to France (France, French). This work was completed with a search through the digital libraries of the École des Hautes Études en Santé Publique (EHESP) and of the Système Universitaire de Documentation (Sudoc) to obtain data from academic works and the gray literature. References cited in studies included in this review were also examined. All references published up to September 2022, written in English or French, presenting the results of original quantitative studies on the prevalence of psychiatric disorders in correctional settings were included. Two researchers independently extracted data from included references according to a pre-established protocol.

Among 501 records identified, a total of 35 papers based on 24 epidemiological studies met the eligibility criteria for inclusion in this review: 16 were cross-sectional, 7 retrospective and 1 both cross-sectional and retrospective. All papers were published between 1999 and 2022. We found one European study, 5 international studies, 18 regional or local studies. Of these, 21 studies had all-male or mixed gender samples (but when the sample was mixed gender, it was always at least 92% male). Almost half of the studies (n=11) involved a small sample of fewer than 500 persons. Half of the studies involved a sample of recently incarcerated persons: 6 involved a random sample of persons in detention, and 1 involved a sample of people incarcerated for more than 5 years. The last 5 studies focused on persons aged over 50 years and incarcerated for more than one year (n=1), incarcerated for sexual offences (n=2), placed in disciplinary cells (n=1) or in a special wing for radicalized or suspected radicalized individuals (n=1). Nine studies used standardized and validated diagnostic tools. According to the 4 studies involving representative samples and using standardized and validated diagnostic tools, the prevalence of the following psychiatric disorders was: 29.4-44.4% for anxiety disorders, 5-14.2% for PTSD, 28-31.2% for mood disorders, 6.9-17% for psychotic disorders, 32% for personality disorders and 11% for ADHD.

This systematic review of the literature highlights the high prevalence of psychiatric disorders in French prisons. The data collected are in line with international studies. The great methodological heterogeneity of the papers included in this review calls for further rigorous research to better understand the rates of mental disorders in French prisons and to explore their determinants.