Investigators

Michael Curtis


Supervisors

Professor Paul Dietze, Professor Mark Stoové


Background

PWID are imprisoned at higher rates than the general population. Surveys of Australian people who inject drugs in 2017 found that heroin remains the most frequently injected drug. The primary role of opioid substitution therapy (OST) is to reduce the harms associated with the use of opiates such as heroin through the encouragement of cessation, periods of abstinence or reducing the frequency of drug use. Community OST has demonstrated its effectiveness in reducing heroin use and retaining patients in treatment when compared to non-opioid-replacement therapies. Prison-based OST programs have been found to reduce in-prison IDU, in-prison needle sharing and reduce mortality. However, despite the widespread use of OST in Australian prisons, there is limited research describing typical patterns of OST utilisation during incarceration and post-release and factors that influence OST retention and uptake. 


Aims

The primary objective of this research program is to inform policy and practice to optimise OST program delivery by determining the role of OST provided in prison and post-prison release in reducing harm associated with injecting drug use. This objective will be achieved through a series of five studies that specifically aim to determine:

  • Patterns of in-prison and post-release OST use and factors associated with OST utilisation and retention during and following release from prison
  • The impact of OST on post-release patterns of drug use following release from prison
  • Whether OST participation impacts patterns of health service engagement following release from prison.
  • The impact of OST participation on post-release morbidity and mortality following release from prison 

Methods

This PhD will analyse primary and secondary linked data from the Prison and Transition Health Cohort Study (PATH). Baseline PATH interviews involved the collection of extensive substance use, physical and mental health, sociodemographic, and service engagement self-report data from soon-to-be-released male prisoners who reported regular IDU during the six months immediately prior to incarceration. Subsequent rounds of face-to-face data collection occurred three, 12 and 24 months post-release. These self-report data are supplemented by two, five and 10 year post-release data-linkage to Medicare Benefits Scheme (MBS), Pharmaceutical Benefits Scheme (PBS), Victorian mental health system, Victorian hospital and emergency departments, Victorian Alcohol and Drug Information System (ADIS), National Death Index (NDI), National Coronial Information Service, Victorian criminal justice and national housing databases. PATH data are a unique resource allowing the construction of a comprehensive picture of the impact of OST programs during incarceration and post-release on the substance use, patterns of health service utilisation and broader morbidity and mortality outcomes of this key population.

Analyses will utilise data on prospective patterns of OST exposure and outcomes of interest, while taking account of time variant factors potentially mediating the impact of OST. Fixed or random effects general linear model regression approaches will be applied to panel/cross sectional time series datasets depending upon the variables observed and unobserved, assessment of correlations between variables, and within participant variability in data. Time-to-event survival analyses and Cox regression will be applied to time-to-event outcomes of interest. 


Significance

This project will provide novel insights regarding the factors influencing OST participation and retention among people in prison and following release. The project will, for the first time, describe the impact of OST on patterns of drug use, the utilisation of health services and morbidity and mortality outcomes in this population during and after release from prison. The greatly improved understanding of the role of prison and community OST programs in preventing ongoing harms associated with IDU achieved in this research will inform policy and practice.


Progress

Candidature commenced in March 2019. 


Timeline

2019 – 2022

Contact

For more information relating to this project, please contact Michael Curtis: