The health needs of people leaving prison with a history of methamphetamine and/or opioid use

Abstract Introduction Methamphetamine use is more common than opioid use among prison entrants in some countries, including Australia, yet most research and policy focuses on opioid use. This suggests that traditional opioid‐focused interventions are no longer appropriate for the majority of this group in countries such as Australia. To inform policy and practice, we compared socio‐demographic characteristics and health needs of people leaving prison with a history of methamphetamine use and/or opioid use. Methods A cross‐sectional survey of incarcerated adults administered the World Health Organization Alcohol, Smoking and Substance Involvement Screening Test was used to identify moderate‐/high‐risk methamphetamine use (n = 909), opioid use (n = 115) or combined methamphetamine/opioid use (n = 356) before incarceration. We compared groups using modified log‐linked Poisson regression with robust error variance. Results Compared to the opioid‐only group, the methamphetamine‐only group were: significantly more often aged <25 years; significantly more likely to identify as Indigenous; significantly less likely to have a history of prior incarceration, drug injection or overdose. A significantly lower proportion of methamphetamine‐only and methamphetamine‐and‐opioid participants self‐reported current hepatitis C infection compared to opioid‐only participants. A majority of participants in all groups screened positive for current psychological distress according to the K10. Discussion and Conclusions People leaving prison with a history of methamphetamine use differ from opioid users with respect to demographics, patterns of substance use and related health concerns. Treatment and harm reduction efforts for people who experience incarceration must respond to patterns of drug use in this population, and invest at scale in coordinated, continuous services for co‐occurring substance use and mental health problems.


Key Point Summary
• Methamphetamine use is many times more prevalent than opioid use among people entering prison in Australia and other countries.• A history of injecting drug use is reported by people in prison who have used methamphetamine and/or opioids in the past.• Using opioid substitution therapies to reduce the risk of blood-borne virus transmission among people in prison will likely miss a large proportion of injecting drug users.• Increased treatment and support for both substance use and mental illness that commence in prison and continue after release into the community are urgently needed.

| INTRODUCTION
There is growing evidence of the adverse health impacts of methamphetamine use [1,2], including increased numbers of methamphetamine-related deaths [3].The use of methamphetamine has also become more prominent among people who go to prison in some countries [4] and rates of methamphetamine use are often many times higher than opioids among this group [5,6].Despite this, prison health literature overwhelmingly focusses on opioid use, including related deaths [7], injecting drug use [8], the transmission of blood-borne viruses (BBV) [9] and opioid substitution therapy [10].
More information is needed on the use of methamphetamine among people who experience incarceration to help to inform treatment strategies, relapse prevention and harm reduction efforts.To address this knowledge gap we analysed data from the Health After Release from Prison study: the largest ever prospective cohort of adults transitioning from prison to the community in Australia [11].We compared the socio-demographic characteristics and health status (BBV exposure, overdose, mental health) for people who had used opioids, methamphetamine or both drugs at moderate to high-risk levels in the 3 months prior to incarceration.

| Procedure and participants
This is a cross-sectional study using data from the baseline survey of a cohort of adults prior to their release from prison.Participants were recruited from seven prisons in Queensland between 2008 and 2010, and five prisons in Western Australia between 2013 and 2016.Adults (18 years and over, including both males and females) who were incarcerated for at least 4 weeks, and expected to be released within 6 weeks, were invited to participate in the study.Of the 3867 individuals invited, 2698 consented, a recruitment fraction of 69.8%.Those consenting then completed the baseline survey at some point in the 6 weeks prior to their expected release from prison.All individuals provided informed consent prior to participation.The survey was administered face-to-face by trained research staff not affiliated with corrective services and took 60-90 min to complete.Participants were not offered any incentive to participate in the baseline survey.
During the baseline survey, we assessed substance use in the 3 months prior to incarceration using the World Health Organization Alcohol, Smoking and Substance Involvement Screening Test (ASSIST) [12].Participants were requested to think back to their drug use in 3 months before they were incarcerated when completing the ASSIST items.Based on their responses to the ASSIST, only participants identified as having engaged in moderate or high-risk methamphetamine and/or opioid use (defined as a score of ≥4 on the ASSIST) in the 3 months before they were incarcerated were included in this analysis (n = 1380).

| Socio-demographic characteristics
At baseline age, Indigenous status, previous incarceration, current relationship status and employment/housing status in the 6 months before incarceration were selfreported.Sex was inferred from the prison where participants were recruited.

| Mental health
Participants self-reported lifetime diagnoses of mental disorder (diagnosed by a doctor, psychologist or psychiatrist) in response to questions adapted from the Australian National Health Survey [13].Those responding in the affirmative indicated if they had been diagnosed with anxiety, depression, any substance use disorder or schizophrenia.
Current psychological distress at baseline was assessed using the Kessler Psychological Distress Scale [14].Participants were classified as experiencing low/no psychological distress (score of <16) or moderate/high/ very high distress (score of ≥16), consistent with the National Health Survey [15].

| BBV and sexually transmitted infections
Participants were asked if they were currently infected with a BBV: hepatitis A, hepatitis B, hepatitis C virus (HCV) and/or HIV.Participants were also asked if they ever had any of the following sexually transmitted infections (STI): gonorrhoea, genital warts, genital herpes, chlamydia or syphilis (combined to create a single STI variable).

| BBV risk behaviours and overdose
Participants were asked if they had ever injected drugs, injected drugs in prison, injected during their current period of incarceration, shared injecting equipment, shared injecting equipment in prison and/or received a high-risk tattoo (been tattooed outside of a licensed or regulated tattooing premises).Participants were also asked whether they had ever self-harmed and whether they had ever overdosed or become unconscious as a result of taking drugs.

| Statistical analysis
Participants were assigned to one of three mutually exclusive groups: (i) methamphetamine use only ("methonly" group); (ii) opioid use only ("opioid-only" group, the reference group); and (iii) methamphetamine and opioid use ("meth-and-opioid" group).All other variables were either binary or re-coded as binary for analysis.We performed univariate modified log-linked Poisson regression with robust error variance to compute the relative risk (RR) of the opioid-only group to each other group, as previously recommended [16].We used Stata version 16 [17] for all statistical analyses.

| RESULTS
Of the 1380 eligible participants, 23% (n = 315) were female and 77% (n = 1065) were male.We assigned 909 (66%) to the meth-only group, 115 (8%) to the opioid-only group and 356 (26%) to the meth-and-opioid group based on their responses to the ASSIST, relating to their use of each drug in the 3 months prior to incarceration.The majority of the meth-only group had been incarcerated prior to their current period of incarceration (74%), had ever injected drugs (79%) and had ever engaged in highrisk tattooing (59%), with a minority having been employed in the 6 months before prison (33%) or in a current stable relationship at baseline (36%) (Table 1).
A majority (53%) of participants reported ever receiving a mental illness diagnosis, with the meth-and-opioid group having the highest proportion (65%), and the meth-only group the lowest (48%).There was no significant difference between either methamphetamine group and the opioid-only group.A majority (59%) of meth-only participants screened for moderate/high distress on the Kessler Psychological Distress Scale at baseline; this was not significantly different from the opioid-only group.

| DISCUSSION
In our cohort, a history of moderate-/high-risk methamphetamine use was far more common than a history of moderate-/high-risk opioid use.A majority reported diagnosis of a mental disorder and most reported significant psychological distress at baseline.Participants with a history of methamphetamine use were younger, more likely to be Indigenous, and less likely to inject drugs or have overdosed than their opioid-using counterparts.Nevertheless, most of these individuals require coordinated, continuous, multidisciplinary care to address underlying physical health, mental health, substance use and psychosocial needs.
Echoing previous Australian research [6], we confirmed that methamphetamine is the primary substance of concern among the majority of people entering Australian prisons, with a high proportion reporting a history of both methamphetamine use and mental illness, as well as poor psychosocial profiles.We observed substantially fewer participants reporting injecting drug use during their current sentence than those who reported ever injecting drugs, suggesting that drug use likely reduces for many during prison.The implications of this are that tolerances may decrease so that the risk of overdose is high if drug use resumes after prison, as has been observed previously [18][19][20].This, along with the high rates of mental illness we observed, means a tailored multi-disciplinary response is needed in the period after release from prison to address likely dual diagnosis, as well as providing welfare and psychosocial support at scale in the period after release from prison; aimed at preventing the poor post-release drug-related health outcomes that often occur.Improving the co-ordination of mental health and alcohol and other drug services is essential, as the siloing of these services is a perennial issue [21].
Current HCV infection prevalence was high across our sample, and while meth-only participants were the group with the lowest prevalence, this was still more than 18 times higher than Australian general population estimates [22].However as the meth-only cohort were significantly younger than their opioid-using counterparts, and the vast majority reported injecting drug use, it could be a 'matter of time' before they become infected.The high prevalence of current HCV infection across our sample highlights the importance of BBV prevention in this population; however, our findings suggesting that current opioid substitution therapy interventions [10] likely miss the large number of people using methamphetamine requiring assistance to reduce injecting, so alternatives need to be considered.
Although we did not find a significant difference between either of our methamphetamine groups and opioid-only group with respect to reporting a lifetime STI, the proportion of participants in the methamphetamine groups were at least 1.5 times higher than estimates from the Australian population [23].Given evidence that people who inject methamphetamine are at an increased risk of contracting an STI [24], additional support to address both injecting methamphetamine use and high-risk sexual behaviour is likely warranted for this group.
Treating people using opioids and methamphetamine concurrently is an ongoing challenge, with mental health morbidity highest among this group in our study.Increases internationally in concurrent opioid and methamphetamine use [25] and fatal and non-fatal overdoses involving these two drugs [26] highlight the ongoing challenges faced in preventing harm for this group.One area of urgent need is for effective pharmacotherapy options for this group, with a dearth of evidence in the area, consisting of a sole randomised controlled trial investigating the use of naltrexone to treat people with co-occurring methamphetamine and opioid use disorder showing modest efficacy [27,28].Furthermore, the poor efficacy of opioid substitution therapy when opioid use is accompanied by methamphetamine use [29], highlights the urgent need for further research to inform improved treatment options, including pharmacotherapy, for people using these drugs together.This is crucial given that the meth-and-opioid group outnumbered the opioid-only group by 3:1 in our study.
When planning services, the younger age and larger proportion of Indigenous participants in our meth-only group compared to the opioid use groups should be considered.Given the higher proportion of Indigenous participants with a history of moderate-/high-risk methamphetamine than opioid use in our study, a failure to respond to demand for methamphetamine use treatment risks compounding health and social inequities experienced by Indigenous people, who are over-represented in the criminal justice system [30,31].
Strengths of our study include the large, multi-jurisdictional sample and our use of the validated ASSIST to assess moderate-/high-risk drug use.A limitation was reliance on self-report data.Recall bias and social desirability bias, particularly where stigmatised behaviours such as drug use are involved, may result in under-reporting; however, a previous review has found that self-reports of drug use and drugrelated problems can be reliable and valid [32].Self-report data on HCV infection should be interpreted with caution because these may be influenced by testing rates, which may be lower among people who use methamphetamine when compared to opioids, and our findings are inconsistent with other research [33].For non-custodial settings, only lifetime injecting drug use data were available, so it was not possible to ascertain how close to the commencement of incarceration participants were injecting.Finally, we only recruited participants from two Australian states to our results may not be generalisable across Australia; however, these two states account for around 39% of all prisoners (and 47% of all Indigenous prisoners) in Australia [30].
A history of moderate-/high-risk methamphetamine use is far more common than opioid use among people in Australian prisons.A majority of people who use methamphetamine and/or opioids have a history of mental illness, with those using methamphetamine and opioids concurrently having the most complex mental health and BBV profile.Multi-disciplinary support is urgently needed to respond to concurrent alcohol and other drug use and mental illness in this group both during incarceration, and as they transition back into the community.