Release from prison: Examining risk factors for death among former prisoners

Background. The United States has the largest prison population and rate of incarceration in the world. Nearly all prisoners will eventually be released. Former prisoners are at high risk of death after release from prison, yet little is known about risk factors for death. The aim of this study was to determine if criminal offense type was associated with death after release among former prisoners. Specifically, we sought to determine if 1) violent crime was associated with overall mortality, death from homicide, or death from suicide; and 2) if drug crime was associated with overall mortality or death from overdose. Our goal was to identify criminal history factors associated with death after release from prison to guide interventions targeting this vulnerable population.

Methods. This was a secondary analysis of a retrospective cohort study of 30,237 prisoners released 38,809 times from Washington state prisons from July 1999 to December 2003. Our main predictor variable was criminal offense type (property, violent, drug, parole violation, and other). Covariates included age, sex, race/ethnicity, mental illness, release type, and length of incarceration. Outcome variables included overall mortality, overdose, homicide, and suicide. We used Cox proportional hazards regression to compare hazard ratios (HR) for death after release from prison. We conducted these analyses using STATA9.2.

Results. Criminal offense was not significantly associated with risk of overall mortality, overdose, homicide, or suicide. However, several covariates were significant. Latinos had decreased risk of overall mortality after release compared to whites (HR 0.56, p=0.002). For age, each year increase was associated with an increase in risk of overall mortality (HR 1.05 under age 50, p<0.001; HR 1.10 over age 50, p<0.001). As length of incarceration increased by year, risk of overall mortality decreased (HR 0.94, p=0.003). Positive history of mental illness was associated with increased risk of overall mortality (HR 1.46, p=0.015). Females had lower risk of suicide compared to males (HR 0.13, p=0.040). Lastly, blacks had higher risk of homicide and lower risk of suicide compared to whites (HR 3.16, p<0.001; HR 0.10, p=0.023).

Conclusion. Our finding that offense type was not associated with post-release mortality highlights the need for a comprehensive approach to reducing the risk of death after release from prison that does not target individuals by offense category. Further research is needed to determine additional risk factors for death among former prisoners that may span beyond the individual to the family, community and state level.