Rates, causes, and risk factors for death among justice-involved young people in Australia: a retrospective, population-based data linkage study

Abstract

Background

Children and adolescents exposed to the youth justice system have poor health profiles, but little is known about their subsequent mortality. We aimed to examine mortality outcomes in a large, state-wide cohort of young people in Australia who had contact with the youth justice system.

Methods

We linked youth justice records in the state of Queensland, Australia from July 1, 1993, to June 30, 2014, with adult correctional records and the National Death Index, for records up to Jan 31, 2017. We calculated all-cause and cause-specific crude mortality rates per 100 000 person-years, and age-standardised and sex-standardised mortality ratios with 95% CIs. Calculations were performed for the whole cohort and in subgroups defined by sex, Indigenous status, and youth justice history. We used survival analysis to identify demographic and criminal justice factors associated with all-cause mortality.

Findings

Of 49 011 individuals in the study sample, 321 were excluded due to data linkage or data quality issues and 20 were excluded as they did not have an age or date of birth recorded, which resulted in 48 670 (99·3%) participants. 11 897 (24·4%) participants were female, 36 773 (75·6%) were male, and 13 250 (27·2%) were Indigenous. During a median of 13·5 years (IQR 8·4–18·4) of follow-up, we observed 1431 (2·9%) deaths among the 48 670 participants. Median age at end of follow-up was 28·6 years (IQR 23·6–33·6). The most common causes of death were suicide (495 [34·6%]), transport accidents (244 [17·1%]), and accidental drug poisoning (209 [14·6%]). The all-cause crude mortality rate was 218·9 deaths (95% CI 207·9–230·6) and the all-cause standard mortality ratio was 4·2 (3·9–4·4). In multivariable analyses, mortality rates were higher for males (adjusted hazard ratio [aHR] 1·5 [95% CI 1·3–1·7]); those who had been subject to community supervision (aHR 1·3 [1·1–1·5]), or detention (aHR 2·1 [1·8–2·4]) versus charge only; and those under adult correctional supervision in the community (aHR 1·9 [1·5–2·4]) versus unsupervised. More than half of the observed deaths occurred before 25 years of age, and very few (1·6%) occurred in custody.

Interpretation

Justice-involved young people are at markedly increased risk of premature death from largely preventable causes. Reducing the burden of preventable death among these young people will require coordinated, multi-sectoral responses that extend beyond the criminal justice system.

Funding

National Health and Medical Research Council, Australia.