Objective
Incarcerated individuals exhibit higher suicide rates compared to the general population. Investigating risk factors aids in developing effective public policies and interventions. The goal of this study was to assess and analyze factors predicting both suicidal thoughts and suicide attempts in a population of male incarcerated individuals who engage in the use of multiple psychoactive substances.

Method
A cross-sectional observational study was conducted. A total of 174 male individuals deprived of liberty participated in the study, all of whom were serving a closed regime sentence during the data collection steps. Participants were assessed with the following instruments: the “Addiction Severity Index” (ASI-6) and the “Barratt Impulsiveness Scale” (BIS-11).   

Results
Amongst our sample, prevalences of 36.7% in suicidal ideation and of 16.0% in suicide attempts were found. Impulsivity (OR = 1.098, 95% CI: 1.008 – 1.197), social support (OR = 0.281, 95% CI: 0.085 – 0.925), witnessing someone being killed or beaten (OR = 5.173, 95% CI: 2.143 – 12.486), cigarette use (OR = 3.309, 95% CI: 1.063 – 10.293), and cocaine use (OR = 2.678, 95% CI: 1.040 – 6.897) were also found to be associated with suicidal ideation. No significant associations were found between drug use and suicide attempts.

Conclusion
A high prevalence of suicidal behaviors was observed in the study’s sample, with findings demonstrating that impulsivity moderately differentiates the groups ‘with’ and ‘without’ suicidal ideation. Traumatic life events and substance use were also associated with suicide ideation, while social support was established as a protective factor for it.