Incidence and factors associated with discontinuation of opioid agonist therapy among people who inject drugs in Australia

Deimplementation in the provision of opioid agonist treatment to achieve equity of care for people engaged in treatment: a qualitative study

BACKGROUND

Deimplementation, the removal or reduction of potentially hazardous approaches to care, is key to progressing social equity in health. While the benefits of opioid agonist treatment (OAT) are well-evidenced, wide variability in the provision of treatment attenuates positive outcomes. During the COVID-19 pandemic, OAT services deimplemented aspects of provision which had long been central to treatment in Australia; supervised dosing, urine drug screening, and frequent in-person attendance for review. This analysis explored how providers considered social inequity in health of patients in the deimplementation of restrictive OAT provision during the COVID-19 pandemic.

METHODS

Between August and December 2020, semi-structured interviews were conducted with 29 OAT providers in Australia. Codes relating to the social determinants of client retention in OAT were clustered according to how providers considered deimplementation in relation to social inequities. Normalisation Process Theory was then used to analyse the clusters in relation to how providers understood their work during the COVID-19 pandemic as responding to systemic issues that condition OAT access.

RESULTS

We explored four overarching themes based on constructs from Normalisation Process Theory: adaptive execution, cognitive participation, normative restructuring, and sustainment. Accounts of adaptive execution demonstrated tensions between providers' conceptions of equity and patient autonomy. Cognitive participation and normative restructuring were integral to the workability of rapid and drastic changes within the OAT services. Key transformative actors included communities of practice and "thought leaders" who had long supported deimplementation for more humane care. At this early stage of the pandemic, providers had already begun to consider how this period could inform sustainment of deimplementation. When considering a future, post-pandemic period, several providers expressed discomfort at operating with "evidence-enough" and called for narrowly defined types of data on adverse events (e.g. overdose) and expert consensus on takeaway doses.

CONCLUSIONS

The possibilities for achieving social equity in health are limited by the divergent treatment goals of providers and people receiving OAT. Sustained and equitable deimplementation of obtrusive aspects of OAT provision require co-created treatment goals, patient-centred monitoring and evaluation, and access to a supportive community of practice for providers.

Discontinuation of opioid agonist treatment following release from prison in a cohort of men who injected drugs prior to imprisonment in Victoria, Australia: A discrete-time survival analysis

BACKGROUND

Retention in opioid agonist treatment (OAT) following release from prison is associated with improved outcomes, however factors associated with post-release OAT discontinuation in Australia are poorly understood. We examined post-release OAT discontinuation in a cohort of men who engaged in approximately monthly injecting drug use (IDU) prior to imprisonment in Victoria, Australia.

METHODS

Longitudinal data were used to calculate incidence of first-event post-release OAT discontinuation among men released from prison receiving OAT, and single-event discrete-time survival methods were used to estimate associations with post-release OAT discontinuation.

RESULTS

Among 110 participants, 55 OAT discontinuations were observed in the two years post-release, an overall crude incidence rate (IR) of 46 per 100 person-years (PY) (95 % confidence interval [95 %CI]: 36-60 per 100PY). Incidence was greatest between release from prison and first follow-up (IR: 84 per 100PY, 95 %CI: 62-116 per 100PY). Initiating OAT during index imprisonment (versus transitioning from community OAT; adjusted hazard rate [AHR]: 2.17, 95 %CI: 1.14-4.13) and identifying as Aboriginal and/or Torres Strait Islander (AHR: 4.95, 95 %CI: 2.00-12.25) were associated with an increased hazard of OAT discontinuation.

CONCLUSION

In a cohort of men with recent histories of IDU released from prison receiving OAT, half reported OAT discontinuation within two years of release from prison, with incidence of discontinuation greatest soon after prison-release. Targeted support for men who initiate OAT during episodes of imprisonment and Aboriginal and/or Torres Strait Islander peoples is necessary to reduce incidence of OAT discontinuation among people at greatest risk of discontinuation.

Incidence of primary hepatitis C virus infection among people who inject drugs in Australia pre- and post-unrestricted availability of direct acting antiviral therapies

AIMS

The 2016 Global Health Sector Strategy (GHSS) on viral hepatitis aims to reduce new hepatitis C virus (HCV) infections by 80% by 2030, including a 30% reduction by 2020. This study aimed to estimate primary HCV incident infection among a national sample of people who inject drugs (PWID) before and after the introduction of unrestricted access to HCV direct-acting antiviral (DAA) therapy via Australia's Pharmaceutical Benefits Scheme in 2016.

DESIGN

A simple deterministic linkage method identified repeat respondents in serial cross-sectional surveys conducted among PWID. Two separate retrospective cohorts of HCV antibody-negative respondents were created, corresponding to the pre- (2010-15) and post- (2016-21) DAA time-periods.

SETTING AND PARTICIPANTS

This study took place in Australia. Among 757 PWID retained (376 pre-DAA, 381 post-DAA), more than half were male (60%), the majority were heterosexual (80%), the median age was 40 years (interquartile range = 33-46 years) and the predominant drugs last injected were heroin (24%), pharmaceutical opioids (27%) and methamphetamine (41%).

MEASUREMENTS

The primary outcome was HCV seroconversion, defined as a negative HCV antibody test result followed by a positive HCV antibody result. Time to primary incident HCV infection was estimated using the person-years (PY) method.

FINDINGS

A total 97 of 376 (2010-15) and 41 of 381 (2016-21) HCV seroconversions were identified. Primary HCV incidence more than halved, from 13.6 per 100 PY [95% confidence intervals (CI) = 11.2, 16.6] in 2010-15 to 5.4 per 100 PY (95% CI = 3.9, 7.3) in 2016-21. The decline was independent of observed differences in demographic and drug use characteristics over the two time-periods (adjusted hazard ratio = 0.47, 95% CI = 0.31-0.69, P < 0.001).

CONCLUSIONS

Australia has had a 53% reduction in primary hepatitis C virus (HCV) incidence among people who inject drugs following unrestricted availability of HCV direct acting antiviral therapy in March 2016. Given that PWID are the predominant population at risk of HCV infection in Australia, findings add to the evidence that Australia has probably met its 2020 Global Health Sector Strategy subtarget of a 30% decline in new infections.

Modeling the population-level impact of opioid agonist treatment on mortality among people accessing treatment between 2001 and 2020 in New South Wales, Australia

BACKGROUND AND AIMS

The individual-level effectiveness of opioid agonist treatment (OAT) in reducing mortality is well established, but there is less evidence on population-level benefits. We use modeling informed with linked data from the OAT program in New South Wales (NSW), Australia, to estimate the impact of OAT provision in the community and prisons on mortality and the impact of eliminating excess mortality during OAT initiation/discontinuation.

DESIGN

Dynamic modeling.

SETTING AND PARTICIPANTS

A cohort of 49 359 individuals who ever received OAT in NSW from 2001 to 2018.

MEASUREMENTS

Receipt of OAT was represented through five stages: (i) first month on OAT, (ii) short (1-9 months) and (iii) longer (9+ months) duration on OAT, (iv) first month following OAT discontinuation and (v) rest of time following OAT discontinuation. Incarceration was represented as four strata: (i) never or not incarcerated in the past year, (ii) currently incarcerated, (iii) released from prison within the past month and (iv) released from prison 1-12 months ago. The model incorporated elevated mortality post-release from prison and OAT impact on reducing mortality and incarceration.

FINDINGS

Among the cohort, mortality was 0.9 per 100 person-years, OAT coverage and retention remained high (> 50%, 1.74 years/episode). During 2001-20, we estimate that OAT provision reduced overdose and other cause mortality among the cohort by 52.8% [95% credible interval (CrI) = 49.4-56.9%] and 26.6% (95% CrI =22.1-30.5%), respectively. We estimate 1.2 deaths averted and 9.7 life-years gained per 100 person-years on OAT. Prison OAT with post-release OAT-linkage accounted for 12.4% (95% CrI = 11.5-13.5%) of all deaths averted by the OAT program, primarily through preventing deaths in the first month post-release. Preventing elevated mortality during OAT initiation and discontinuation could have averted up to 1.4% (95% CrI =  0.8-2.0%) and 3.0% (95% CrI = 2.1-5.3%) of deaths, respectively.

CONCLUSION

The community and prison opioid agonist treatment program in New South Wales, Australia appears to have substantially reduced population-level overdose and all-cause mortality in the past 20 years, partially due to high retention.

Gaps in hepatitis C virus prevention and care for HIV-hepatitis C virus co-infected people who inject drugs in Canada

BACKGROUND

People who inject drugs (PWID) living with HIV are a priority population for eliminating hepatitis C virus (HCV) as a public health threat. Maximizing access to HCV prevention and treatment strategies are key steps towards elimination. We aimed to evaluate engagement in harm reduction programs and HCV treatment, and to describe injection practices among HIV-HCV co-infected PWID in Canada from 2003 to 2019.

METHODS

We included Canadian Coinfection Cohort study participants who reported injecting drugs between 2003 and 2019 in Quebec, Ontario, Saskatchewan, and British Columbia, Canada. We investigated temporal trends in HCV treatment uptake, efficacy, and effectiveness; injection practices; and engagement in harm reduction programs in three time periods based on HCV treatment availability: 1) interferon/ribavirin (2003-2010); 2) first-generation direct acting antivirals (DAAs) (2011-2013); 3) second-generation DAAs (2014-2019). Harm reduction services assessed included needle and syringe programs (NSP), opioid agonist therapy (OAT), and supervised injection sites (SIS).

RESULTS

Median age of participants (N = 1,077) at cohort entry was 44 years; 69% were males. Province-specific HCV treatment rates increased among HCV RNA-positive PWID, reaching 16 to 31 per 100 person-years in 2014-2019. Treatment efficacy improved from a 50 to 70% range in 2003-2010 to >90% across provinces in 2014-2019. Drug injecting patterns among active PWID varied by province, with an overall decrease in cocaine injection frequency and increasing opioid injections. In the most recent time period (2014-2019), needle/syringe sharing was reported at 8-22% of visits. Gaps remained in engagement in harm reduction programs: NSP use decreased (58-70% of visits), OAT engagement among opioid users was low (8-26% of visits), and participants rarely used SIS (1-15% of visits).

CONCLUSION

HCV treatment uptake and outcomes have improved among HIV-HCV coinfected PWID. Yet, this population remains exposed to drug-related harms, highlighting the need to tie HCV elimination strategies with enhanced harm reduction programs to improve overall health for this population.

Prevalence and correlates of multiple non-fatal opioid overdoses among people who inject drugs who utilise needle syringe programs in Australia

BACKGROUND

Non-fatal overdose (NFOD) is a major cause of morbidity among people who inject drugs (PWID) and multiple NFOD is associated with increased risk of fatal overdose. Despite this, few studies have examined the prevalence and correlates of drug-specific multiple NFOD. The current study aimed to determine the prevalence and correlates of recent multiple non-fatal opioid overdose (NFOOD) among PWID who access needle syringe programs (NSPs) in Australia.

METHODS

The Australian Needle and Syringe Program Survey is conducted annually and was conducted at 46 sites across Australia in 2019. Participation involves completion of a self-administered questionnaire and a capillary dried blood spot for HIV and hepatitis C virus testing. In 2019, respondents who reported a minimum of one NFOOD in the previous 12 months (recent NFOOD) were asked to complete supplementary questions regarding their last NFOOD. Bivariate and multivariate logistic regression were used to determine factors independently associated with multiple recent NFOOD.

RESULTS

A total of 222 respondents reported recent NFOOD. Respondents were predominantly male (59%), one third (39%) were aged less than 39 years and 73% reported last injecting heroin at their last NFOOD. One in two respondents (48%, n = 107) reported multiple opioid overdoses (median 3, interquartile range 2-5). The odds of reporting multiple NFOOD were higher among respondents who reported injecting in a public location at their last NFOOD (adjusted odds ratio [AOR] 2.10, 95% CI 1.14-3.90, p = 0.018) and benzodiazepine use in the 12 h prior to NFOOD (AOR 2.74, 95% CI 1.50-4.99, p = 0.001).

CONCLUSIONS

Multiple NFOOD was prevalent among PWID who utilised NSPs who reported recent NFOOD. Public injecting and benzodiazepine use were associated with increased risk of multiple NFOOD, and there is a need for interventions specifically targeting PWID who report these high risk injecting practices.