Change in Severity of Mental Disorder of Remand Prisoners: An Observational Group-Based Trajectory Study

Background Mental disorder is common among prisoners; however, little is known about how illness severity changes during incarceration, and especially to what extent there are different trajectories of change. Aims Our aims were to investigate trajectories of illness severity among male and female inmates with serious mental disorders, and to investigate whether clinical or demographic variables are associated with different trajectories. Methods We carried out a retrospective cohort study of newly remanded inmates who had three or more serial measures of illness severity as measured by psychiatrists using the Clinical Global Impression-Corrections (CGI-C), and used group-based trajectory modelling to identify trajectories. We investigated whether clinical and demographic variables were associated with different groups. Results We found an overall reduction in the severity of illness (mean change in CGI-C score -0.74, SD 1.5), with women showing greater improvement than men. We identified three distinct trajectories among men and three among women, all showing improvement in illness severity. Approximately 15% of the entire cohort had full resolution of symptoms, whereas the remainder showed partial improvement. Women, younger inmates, and those with substance use disorders were more likely to have full resolution of symptoms. Conclusions Although most prisoners showed improvement, and a small proportion had full resolution of symptoms, a significant number continued to have moderately severe symptoms. There is a need for comprehensive treatment within the detention centre, but also a need for transfer to hospital for those with severe symptoms as improvement within the correctional setting tends to be modest.