Same-visit hepatitis C testing and treatment to accelerate cure among people who inject drugs (the QuickStart Study): a cluster randomised cross-over trial protocol.

INTRODUCTION: Despite universal access to government-funded direct-acting antivirals (DAAs) in 2016, the rate of hepatitis C treatment uptake in Australia has declined substantially. Most hepatitis C is related to injecting drug use; reducing the hepatitis C burden among people who inject drugs (PWID) is, therefore, paramount to reach hepatitis C elimination targets. Increasing DAA uptake by PWID is important for interrupting transmission and reducing incidence, as well as reducing morbidity and mortality and improving quality of life of PWID and meeting Australia's hepatitis C elimination targets. METHODS AND ANALYSIS: A cluster randomised cross-over trial will be conducted with three intervention arms and a control arm. Arm A will receive rapid hepatitis C virus (HCV) antibody testing; arm B will receive rapid HCV antibody and rapid RNA testing; arm C will receive rapid HCV antibody testing and same-day treatment initiation for HCV antibody-positive participants; the control arm will receive standard of care. The primary outcomes will be (a) the proportion of participants with HCV commencing treatment and (b) the proportion of participants with HCV achieving cure. Analyses will be conducted on an intention-to-treat basis with mixed-effects logistic regression models. ETHICS AND DISSEMINATION: The study has been approved by the Alfred Ethics Committee (number HREC/64731/Alfred-2020-217547). Each participant will provide written informed consent. Reportable adverse events will be reported to the reviewing ethics committee. The findings will be presented at scientific conferences and published in peer-reviewed journals. TRIAL REGISTRATION NUMBER: NCT05016609. TRIAL PROGRESSION: The study commenced recruitment on 9 March 2022 and is expected to complete recruitment in December 2024.

Stigma, and factors associated with experiencing stigma, while visiting health-care services among samples of people who use illegal drugs in Australia.

INTRODUCTION: People who inject drugs experience stigma across multiple settings, including when accessing health-care services, however, comparatively little is known about experiences of stigma towards other groups of people who use illegal drugs. This paper examines experience of, and factors associated with, stigma among two samples of people who use illegal drugs when visiting both specialist alcohol and other drug (AOD) and general health-care services. METHODS: Australians who regularly (i.e., ≥monthly) inject drugs (n = 879; illicit drug reporting system [IDRS]) or use ecstasy and/or other illegal stimulants (n = 700; ecstasy and related drugs reporting system [EDRS]) were surveyed between April and July 2022 about past 6-month experience of stigma in the above services. Multi-variable regression analyses were performed to determine the socio-demographic, drug use and health factors associated with stigma. RESULTS: Experiences of stigma in general health-care services were more common among IDRS (40%) than EDRS (24%; p < 0.001) participants, however, experiences were comparable in specialist AOD health-care settings (22% and 20%, respectively; p = 0.687). Gender identity and experiencing high psychological distress were associated with experiencing stigma across both samples. Past-year overdose was associated with experiencing stigma among the IDRS sample, while unstable housing and incomplete high school education were associated with experiencing stigma in the EDRS sample. DISCUSSION AND CONCLUSIONS: Experiences of stigma when accessing health-care services are relatively common across different populations of people who use illegal drugs. Our findings highlight the multiple and intersecting dimensions of stigma and provide further support for recent calls for a universal precautions approach to stigma in health care.

High COVID-19 vaccine uptake following initial hesitancy among people in Australia who inject drugs.

BACKGROUND: Previous studies have reported high COVID-19 vaccine hesitancy among people who inject drugs. We aimed to examine COVID-19 vaccine coverage, motivations and barriers to vaccination, and factors associated with uptake among this population in Australia, 1.5 years after vaccine rollout commenced. METHODS: In June-July 2022, 868 people (66.0 % male, mean age 45.6 years) who regularly inject drugs and reside in an Australian capital city reported the number of COVID-19 vaccine doses they had received and their primary motivation (if vaccinated) or barrier (if unvaccinated) to receive the vaccine. We compared vaccine uptake to Australian population estimates and used logistic regression to identify factors associated with ≥ 2 dose and ≥ 3 dose uptake. RESULTS: Overall, 84.1 % (n = 730) had received at least one COVID-19 vaccine dose, 79.6 % (n = 691) had received ≥ 2 doses, and 46.1 % (n = 400) had received ≥ 3 doses. Participants were less likely to be vaccinated than the Australian general population (prevalence ratio: 0.82, 95 % confidence interval [CI]: 0.76-0.88). Key motivations to receive the vaccine were to protect oneself or others from COVID-19, while barriers pertained to vaccine or government distrust. Opioid agonist treatment (adjusted odds ratio [aOR]: 2.49, 95 % CI: 1.44-4.42), current seasonal influenza vaccine uptake (aOR: 6.76, 95 % CI: 3.18-16.75), and stable housing (aOR: 1.58, 95 % CI: 1.02-2.80) were associated with receipt of at least two vaccine doses. Participants aged ≥ 40 years (versus < 40 years; aOR: 1.66, 95 % CI: 1.10-2.53) or who reported a chronic health condition (aOR: 1.71, 95 % CI: 1.18-2.47) had higher odds of receiving at least three vaccine doses. CONCLUSION: We observed higher COVID-19 vaccine uptake than expected given previous studies of vaccine acceptability among people who inject drugs. However, it was lower than the general population. People who inject drugs and reside in unstable housing are a subpopulation that require support to increase vaccine uptake.

"No-one just does drugs during business hours!": evaluation of a 24/7 primary needle and syringe program in St Kilda, Australia.

BACKGROUND: Primary needle and syringe programs (NSPs) have been integral for the prevention of blood-borne virus (BBV) transmission among people who inject drugs. Despite this, many people who inject drugs face barriers accessing these services, particularly after-hours when most services are closed. To our knowledge, the St Kilda NSP, in Melbourne, Victoria, is the only primary NSP providing 24/7 dedicated stand-alone face-to-face services for people who inject drugs in Australia. We conducted an evaluation of the St Kilda NSP to assess its role and effectiveness in meeting client needs. METHODS: Mixed research methods were used to conduct the evaluation. We analysed four quantitative data sets including the Victorian Needle and Syringe Program Information System data; NSP 'snapshot' survey data; and St Kilda NSP records of after-hours contacts and naloxone training events. Qualitative interviews were conducted with 20 purposively selected NSP clients, which were focused on individual needs, expectations and experiences accessing the service. Interviews were audio recorded and transcribed, and data were analysed thematically. A convergent research design was used to merge the five data sets. RESULTS: St Kilda NSP had 39,898 service contacts in 2018; 72% of contacts occurred outside business hours. Similarly, of 1,185,000 sterile needles and syringes dispatched, 71% were distributed outside business hours. Participants described valuing the after-hours service because drug use patterns did not always align with standard NSP opening hours and after-hours access afforded anonymity when collecting injecting equipment. Narratives highlighted several additional benefits of the 24/7 service, including: access to safer sex equipment; material support; naloxone training; referrals to specialist services; face-to-face emotional and social support from a non-judging worker; and for women involved in sex work in particular, being able to seek refuge when feeling unsafe on the streets. CONCLUSIONS: Our study provides evidence of the social and health benefits (beyond that of preventing BBV transmission) that can be gained through the provision of 24/7 primary NSP services. Findings support the need for the establishment of after-hours primary NSPs in other areas of Australia where active street-based drug markets operate outside business hours and concentrated numbers of people who inject drugs live and spend time.

Injecting drug use and hepatitis C virus infection independently increase biomarkers of inflammatory disease risk which are incompletely restored by curative direct-acting antiviral therapy.

Background: Hepatitis C virus (HCV) infections are more prevalent in people who inject drugs (PWID) who often experience additional health risks. HCV induces inflammation and immune alterations that contribute to hepatic and non-hepatic morbidities. It remains unclear whether curative direct acting antiviral (DAA) therapy completely reverses immune alterations in PWID. Methods: Plasma biomarkers of immune activation associated with chronic disease risk were measured in HCV-seronegative (n=24) and HCV RNA+ (n=32) PWID at baseline and longitudinally after DAA therapy. Adjusted generalised estimating equations were used to assess longitudinal changes in biomarker levels. Comparisons between community controls (n=29) and HCV-seronegative PWID were made using adjusted multiple regression modelling. Results: HCV-seronegative PWID exhibited significantly increased levels of inflammatory biomarkers including soluble (s) TNF-RII, IL-6, sCD14 and sCD163 and the diabetes index HbA1c as compared to community controls. CXCL10, sTNF-RII, vascular cell adhesion molecule-1 and lipopolysaccharide binding protein (LBP) were additionally elevated in PWID with viremic HCV infection as compared to HCV- PWID. Whilst curative DAA therapy reversed some biomarkers, others including LBP and sTNF-RII remained elevated 48 weeks after HCV cure. Conclusion: Elevated levels of inflammatory and chronic disease biomarkers in PWID suggest an increased risk of chronic morbidities such as diabetes and cardiovascular disease. HCV infection in PWID poses an additional disease burden, amplified by the incomplete reversal of immune dysfunction following DAA therapy. These findings highlight the need for heightened clinical surveillance of PWID for chronic inflammatory diseases, particularly those with a history of HCV infection.

Approaches and reporting of alcohol and other drug testing for injured patients in hospital-based studies: A systematic review.

ISSUE: Hospital alcohol and/or other drug (AOD) testing is important for identifying AOD-related injuries; however, testing methods vary. This systematic review aimed to examine biological AOD testing methods from hospital-based studies of injured patients and quantify what proportion reported key information on those testing methods. APPROACH: Observational studies published in English from 2010 onwards involving biological AOD testing for injured patients presenting to hospital were included. Studies examining single injury causes were excluded. Extracted data included concentration thresholds for AOD detection (e.g., lower limits of detection, author-defined cut-offs), test type (e.g., immunoassay, breathalyser) and approach (e.g., routine, clinical discretion), timing of testing, sample type and the proportion of injured cases tested for AODs. KEY FINDINGS: Of 83 included studies, 76 measured alcohol and 37 other drugs. Forty-nine studies defined blood alcohol concentration thresholds (ranging from 0 to 0.1 g/100 mL). Seven studies defined concentration thresholds for other drugs. Testing approach was reported in 39/76 alcohol and 18/37 other drug studies. Sample type was commonly reported (alcohol: n = 69/76; other drugs: n = 28/37); alcohol was typically measured using blood (n = 60) and other drugs using urine (n = 20). Studies that reported the proportion of cases tested (alcohol: n = 53/76; other drugs: n = 28/37), reported that between 0% and 89% of cases were not tested for alcohol and 0% and 91% for other drugs. Timing of testing was often unreported (alcohol: n = 61; other drugs: n = 30). IMPLICATIONS AND CONCLUSION: Variation in AOD testing methods alongside incomplete reporting of those methods limits data comparability and interpretation. Standardised reporting of testing methods will assist AOD-related injury surveillance and prevention.

A narrative systematic review of associations and temporality between use of methamphetamine, ecstasy/MDMA, or cocaine with anxiety or depressive symptoms.

OBJECTIVE: Anxiety and depression are prevalent mental health problems in people who use illicit stimulants. Improved understanding of the temporal relationship between methamphetamine, ecstasy/MDMA, or cocaine use with anxiety or depression informs public health interventions and treatment options for those experiencing this co-occurrence. This narrative systematic review sought to examine associations and temporality between the use of methamphetamine, ecstasy/MDMA, or cocaine, with anxiety or depressive symptoms. Method Systematic searches of 4 electronic databases were conducted up to August 2023. Study eligibility included the measurement of anxiety and/or depressive symptoms, and frequency of illicit stimulant use (methamphetamine, cocaine, or ecstasy/MDMA) at two separate time points, with data analysis of the association between these variables. The Joanna Briggs Critical Appraisal Checklist was utilised to assess quality. Data was extracted, and a narrative synthesis incorporating an eight-criteria framework to assess associations was conducted. Results 4432 studies were screened for eligibility; 11 studies (3 RCTs and 8 prospective cohort studies) were included. Evidence for an association between depressive symptoms and methamphetamine use was demonstrated in six studies, with temporal evidence in three studies supporting methamphetamine use preceding depressive symptoms. Three studies reported an association between cocaine use and depressive symptoms. Evidence for associations with any of the illicit stimulants and anxiety symptoms was lacking. CONCLUSIONS: There was some evidence to support a case for temporality, particularly for methamphetamine use and depressive symptoms. Investing in longitudinal studies is pivotal to understanding the dynamic and reciprocal relationship between illicit stimulant use and anxiety or depressive symptoms. A limitation of the study was the variation in the measurement and analysis of outcomes.

Prevalence of alcohol and other drug detections in non-transport injury events.

OBJECTIVE: To measure the prevalence of alcohol and/or other drug (AOD) detections in suspected major trauma patients with non-transport injuries who presented to an adult major trauma centre. METHODS: This registry-based cohort study examined the prevalence of AOD detections in patients aged ≥18 years who: (i) sustained non-transport injuries; and (ii) met predefined trauma call-out criteria and were therefore managed by an interdisciplinary trauma team between 1 July 2021 and 31 December 2022. Prevalence was measured using routine in-hospital blood alcohol and urine drug screens. RESULTS: A total of 1469 cases met the inclusion criteria. Of cases with a valid blood test (n = 1248, 85.0%), alcohol was detected in 313 (25.1%) patients. Of the 733 (49.9%) cases with urine drug screen results, cannabinoids were most commonly detected (n = 103, 14.1%), followed by benzodiazepines (n = 98, 13.4%), amphetamine-type substances (n = 80, 10.9%), opioids (n = 28, 3.8%) and cocaine (n = 17, 2.3%). Alcohol and/or at least one other drug was detected in 37.4% (n = 472) of cases with either a blood alcohol or urine drug test completed (n = 1263, 86.0%). Multiple substances were detected in 16.6% (n = 119) of cases with both blood alcohol and urine drug screens (n = 718, 48.9%). Detections were prevalent in cases of interpersonal violence (n = 123/179, 68.7%) and intentional self-harm (n = 50/106, 47.2%), and in those occurring on Friday and Saturday nights (n = 118/191, 61.8%). CONCLUSION: AOD detections were common in trauma patients with non-transport injury causes. Population-level surveillance is needed to inform prevention strategies that address AOD use as a significant risk factor for serious injury.

The National Naloxone Reference Group: A collective voice on take-home naloxone policy and practice in Australia.

The National Naloxone Reference Group has played a key role in the development of take-home naloxone programs, policy and practice in Australia. In this commentary we detail the origins of the group, some of its main achievements since its inception and its future directions in light of the major policy changes around naloxone that have recently occurred in Australia.

Parents who inject drugs: Demographics, care arrangements and correlates for child placement in out-of-home care.

INTRODUCTION: Children in families affected by substance use disorders are at high risk of being placed in out-of-home care (OOHC). We aimed to describe the characteristics of parents who inject drugs and identify correlates associated with child placement in OOHC. METHODS: We used baseline data from a community-based cohort of parents who inject drugs (SuperMIX) from Melbourne, Australia. Participants were recruited via convenience, respondent-driven and snowball sampling from April 2008 to November 2020, with follow-up until March 2021. To explore correlates associated with child placement to OOHC, we used multivariable logistic regression and assessed for potential interactions between gender and a range of relevant covariates. RESULTS: Of the 1067 participants, 611 (57%) reported being parents. Fifty-six percent of parents reported child protection involvement. Almost half (49%) had children in OOHC. Nearly half of the parents lived in unstable accommodation (44%) and many of them experienced moderate-severe levels of anxiety (48%) and depression (53%). Female or non-binary gender, identifying as Aboriginal or Torres Strait Islander, experiencing assault and having more children were associated with child removal to OOHC. Of the 563 participants who reported their own childhood care status, 135 (24%) reported they had been removed to OOHC. DISCUSSION AND CONCLUSIONS: We identified high rates of child placement in OOHC among parents who inject drugs. There is a need for targeted health and social services, that are gender and culturally responsive, in addition to systems-level interventions addressing social inequities, such as housing, to support parents to care for their children.

Prevalence of Alcohol and Other Drug Use in Patients Presenting to Hospital for Violence-Related Injuries: A Systematic Review.

Substance use is a risk factor for being both a perpetrator and a victim of violence. The aim of this systematic review was to report the prevalence of acute pre-injury substance use in patients with violence-related injuries. Systematic searches were used to identify observational studies that included patients aged ≥15 years presenting to hospital after violence-related injuries and used objective toxicology measures to report prevalence of acute pre-injury substance use. Studies were grouped based on injury cause (any violence-related, assault, firearm, and other penetrating injuries including stab and incised wounds) and substance type (any substance, alcohol only, drugs other than alcohol only), and they were summarized using narrative synthesis and meta-analyses. This review included 28 studies. Alcohol was detected in 13%-66% of any violence-related injuries (five studies), 4%-71% of assaults (13 studies), 21%-45% of firearm injuries (six studies; pooled estimate = 41%, 95% CI: 40%-42%, n = 9,190), and 9%-66% of other penetrating injuries (nine studies; pooled estimate = 60%, 95% CI: 56%-64%, n = 6,950). Drugs other than alcohol were detected in 37% of any violence-related injuries (one study), 39% of firearm injuries (one study), 7%-49% of assaults (five studies), and 5%-66% of penetrating injuries (three studies). The prevalence of any substance varied across injury categories: any violence-related injuries = 76%-77% (three studies), assaults = 40%-73% (six studies), firearms = n/a, other penetrating injuries = 26%-45% (four studies; pooled estimate = 30%, 95% CI: 24%-37%, n = 319).Overall, substance use was frequently detected in patients presenting to hospital for violence-related injuries. Quantification of substance use in violence-related injuries provides a benchmark for harm reduction and injury prevention strategies.

Distribution of rapid HCV antibody self-test kits via needle/syringe dispensing machines: Implementation and evaluation of the Vend-C pilot study in Melbourne, Australia.

Recent guidance from the World Health Organization strongly recommended hepatitis C virus (HCV) self-testing. We implemented the Vend-C pilot study to explore the effectiveness and feasibility of distributing rapid HCV antibody self-test kits to people who inject drugs via needle/syringe dispensing machines (SDMs). Over a 51-day study period between August and September 2022, we distributed HCV antibody self-test kits via two SDMs. During the study period, 63 self-test kits were dispensed, averaging 1.2 self-test kits per day. Our access methods for evaluation questionnaires failed to attract participants (n = 4). We implemented the Vend-C pilot study in direct response to recent WHO recommendations. While self-test kits were effectively distributed from the two SDMs, our evaluation methodology failed. Consequently, we cannot determine the success of linkage to care. Even so, with HCV treatment numbers dropping in Australia, innovative engagement solutions are needed, and considering the number of self-test kits provided in our pilot, the model could have an important future place in HCV elimination efforts.

Prevalence and incidence of emergency department presentations and hospital separations with injecting-related infections in a longitudinal cohort of people who inject drugs.

People who inject drugs are at risk of acute bacterial and fungal injecting-related infections. There is evidence that incidence of hospitalizations for injecting-related infections are increasing in several countries, but little is known at an individual level. We aimed to examine injecting-related infections in a linked longitudinal cohort of people who inject drugs in Melbourne, Australia. A retrospective descriptive analysis was conducted to estimate the prevalence and incidence of injecting-related infections using administrative emergency department and hospital separation datasets linked to the SuperMIX cohort, from 2008 to 2018. Over the study period, 33% (95%CI: 31-36%) of participants presented to emergency department with any injecting-related infections and 27% (95%CI: 25-30%) were admitted to hospital. Of 1,044 emergency department presentations and 740 hospital separations, skin and soft tissue infections were most common, 88% and 76%, respectively. From 2008 to 2018, there was a substantial increase in emergency department presentations and hospital separations with any injecting-related infections, 48 to 135 per 1,000 person-years, and 18 to 102 per 1,000 person-years, respectively. The results emphasize that injecting-related infections are increasing, and that new models of care are needed to help prevent and facilitate early detection of superficial infection to avoid potentially life-threatening severe infections.

Biases in the collection of blood alcohol data for adult major trauma patients in Victoria, Australia.

BACKGROUND: In-hospital alcohol testing provides an opportunity to implement prevention strategies for patients with high risk of experiencing repeated alcohol-related injuries. However, barriers to alcohol testing in emergency settings can prevent patients from being tested. In this study, we aimed to understand potential biases in current data on the completion of blood alcohol tests for major trauma patients at hospitals in Victoria, Australia. METHODS: Victorian State Trauma Registry data on all adult major trauma patients from 1 January 2018 to 31 December 2021 were used. Characteristics associated with having a blood alcohol test recorded in the registry were assessed using logistic regression models. RESULTS: This study included 14 221 major trauma patients, of which 4563 (32.1%) had a blood alcohol test recorded. Having a blood alcohol test completed was significantly associated with age, socioeconomic disadvantage level, preferred language, having pre-existing mental health or substance use conditions, smoking status, presenting during times associated with heavy community alcohol consumption, injury cause and intent, and Glasgow Coma Scale scores (p<0.05). Restricting analyses to patients from a trauma centre where blood alcohol testing was part of routine clinical care mitigated most biases. However, relative to patients injured while driving a motor vehicle/motorcycle, lower odds of testing were still observed for patients with injuries from flames/scalds/contact burns (adjusted OR (aOR)=0.33, 95% CI 0.18 to 0.61) and low falls (aOR=0.17, 95% CI 0.12 to 0.25). Higher odds of testing were associated with pre-existing mental health (aOR=1.39, 95% CI 1.02 to 1.89) or substance use conditions (aOR=2.33, 95% CI to 1.47-3.70), and living in a more disadvantaged area (most disadvantaged quintile relative to least disadvantaged quintile: aOR=2.30, 95% CI 1.52 to 3.48). CONCLUSION: Biases in the collection of blood alcohol data likely impact the surveillance of alcohol-related injuries. Routine alcohol testing after major trauma is needed to accurately inform epidemiology and the subsequent implementation of strategies for reducing alcohol-related injuries.

Injection Drug Use Frequency Before and After Take-Home Naloxone Training.

Importance: Concerns that take-home naloxone (THN) training may lead to riskier drug use (as a form of overdose risk compensation) remain a substantial barrier to training implementation. However, there was limited good-quality evidence in a systematic review of the association between THN access and subsequent risk compensation behaviors. Objective: To assess whether THN training is associated with changes in overdose risk behaviors, indexed through injecting frequency, in a cohort of people who inject drugs. Design, Setting, and Participants: This cohort study used prospectively collected self-reported behavioral data before and after THN training of participants in The Melbourne Injecting Drug User Cohort Study (SuperMIX). Annual interviews were conducted in and around Melbourne, Victoria, Australia, from 2008 to 2021. SuperMIX participants were adults who regularly injected heroin or methamphetamine in the 6 months preceding their baseline interview. The current study included only people who inject drugs who reported THN training and had participated in at least 1 interview before THN training. Exposure: In 2017, the SuperMIX baseline or follow-up survey began asking participants if and when they had received THN training. The first THN training date that was recorded was included as the exposure variable. Subsequent participant interviews were excluded from analysis. Main Outcomes and Measures: Injecting frequency was the primary outcome and was used as an indicator of overdose risk. Secondary outcomes were opioid injecting frequency, benzodiazepine use frequency, and the proportion of the time drugs were used alone. Fixed-effects generalized linear (Poisson) multilevel modeling was used to estimate the association between THN training and the primary and secondary outcomes. Time-varying covariates included housing status, income, time in study, recent opioid overdose, recent drug treatment, and needle and syringe coverage. Findings were expressed as incidence rate ratios (IRRs) with 95% CIs. Results: There were 1328 participants (mean [SD] age, 32.4 [9.0] years; 893 men [67.2%]) who completed a baseline interview in the SuperMIX cohort, and 965 participants completed either a baseline or follow-up interview in or after 2017. Of these 965 participants, 390 (40.4%) reported THN training. A total of 189 people who inject drugs had pretraining participant interviews with data on injecting frequency and were included in the final analysis (mean [SD] number of interviews over the study period, 6.2 [2.2]). In fixed-effects regression analyses adjusted for covariates, there was no change in the frequency of injecting (IRR, 0.91; 95% CI, 0.69-1.20; P = .51), opioid injecting (IRR, 0.95; 95% CI, 0.74-1.23; P = .71), benzodiazepine use (IRR, 0.96; 95% CI, 0.69-1.33; P = .80), or the proportion of reported time of using drugs alone (IRR, 1.04; 95% CI, 0.86-1.26; P = .67) before and after THN training. Conclusions and Relevance: This cohort study of people who inject drugs found no evidence of an increase in injecting frequency, along with other markers of overdose risk, after THN training and supply. The findings suggest that THN training should not be withheld because of concerns about risk compensation and that advocacy for availability and uptake of THN is required to address unprecedented opioid-associated mortality.

Identifying the Most Effective Recruitment Strategy Using Financial Reimbursements for a Web-Based Peer Network Study With Young People Aged 16-18 Years: Protocol for a Randomized Controlled Trial.

BACKGROUND: Peers are an important determinant of health and well-being during late adolescence; however, there is limited quantitative research examining peer influence. Previous peer network research with adolescents faced methodological limitations and difficulties recruiting young people. OBJECTIVE: This study aims to determine whether a web-based peer network survey is effective at recruiting adolescent peer networks by comparing 2 strategies for reimbursement. METHODS: This study will use a 2-group randomized trial design to test the effectiveness of reimbursements for peer referral in a web-based cross-sectional peer network survey. Young people aged 16-18 years recruited through Instagram, Snapchat, and a survey panel will be randomized to receive either scaled group reimbursement (the experimental group) or fixed individual reimbursement (the control group). All participants will receive a reimbursement of Aus $5 (US $3.70) for their own survey completion. In the experimental group (scaled group reimbursement), all participants within a peer network will receive an additional Aus $5 (US $3.70) voucher for each referred participant who completes the study, up to a maximum total value of Aus $30 (US $22.20) per participant. In the control group (fixed individual reimbursement), participants will only be reimbursed for their own survey completion. Participants' peer networks are assessed during the survey by asking about their close friends. A unique survey link will be generated to share with the participant's nominated friends for the recruitment of secondary participants. Outcomes are the proportion of a participant's peer network and the number of referred peers who complete the survey. The required sample size is 306 primary participants. Using a multilevel logistic regression model, we will assess the effect of the reimbursement intervention on the proportion of primary participants' close friends who complete the survey. The secondary aim is to determine participant characteristics that are associated with successfully recruiting close friends. Young people aged 16-18 years were involved in the development of the study design through focus groups and interviews (n=26). RESULTS: Participant recruitment commenced in 2022. CONCLUSIONS: A longitudinal web-based social network study could provide important data on how social networks and their influence change over time. This trial aims to determine whether scaled group reimbursement can increase the number of peers referred. The outcomes of this trial will improve the recruitment of young people to web-based network studies of sensitive health issues. INTERNATIONAL REGISTERED REPORT IDENTIFIER (IRRID): DERR1-10.2196/44813.

Trends and psychosocial correlates of same day polysubstance use among people who inject drugs in Australia, 2012-2022.

BACKGROUND: Polysubstance use is associated with negative health and social outcomes among people who inject drugs. We aimed to describe trends in polysubstance use and identify psychosocial correlates and associated drug use risk behaviours. We defined polysubstance use as intentional same day use of more than one of three drug classes: opioids, other non-opioid depressants (hereafter 'depressants'), and stimulants. METHODS: We used 10 years (2012-2022, excluding 2020) of data from annual surveys in Australian capital cities with people who inject drugs (N=5657) to construct five mutually exclusive polysubstance use profiles: opioid-depressant, opioid-stimulant, stimulant-depressant, opioid-stimulant-depressant, and single drug class use. We examined time trends using the Mann Kendall test and identified correlates using multinomial logistic regression. RESULTS: Same day polysubstance use was relatively common among this sample (43.6%). Opioid-depressant use was the most frequent polysubstance use profile, but this decreased over the study period (32.6% to 13.3%, p<0.001). This aligned with observed decreases in use of pharmaceutical opioids (p<0.001), opioid agonist treatment (p=0.007), and benzodiazepines (p=0.001). There was no evidence for any trend in the other polysubstance use profiles, although single drug class use increased (51.9% to 64.7%, p=0.031). The different polysubstance use profiles were variously associated with psychosocial factors, including unstable housing and very high psychological distress, and other drug use risk behaviours, including non-fatal overdose, receptive and/or distributive needle sharing, and reusing one's own needles. CONCLUSION: Same day polysubstance use has remained relatively common among this sample over time, although the typology has changed. Collectively, our findings point to diverse drug use patterns among people who inject drugs and reiterate the need for a range of harm reduction, treatment, and support options.

Correlates of poor oral health related quality of life in a cohort of people who use methamphetamine in Australia.

OBJECTIVES: Methamphetamine use impacts oral health, but little is known about its impacts on oral health related quality of life (OHRQoL). In this study we examined OHRQoL in a cohort of people who use methamphetamine and assessed associations with sociodemographic, behavioural, psychosocial and dental service utilisation correlates. A secondary aim was to examine the relationship between methamphetamine route of administration and OHRQoL, to test whether smoking the drug is associated with reduced OHRQoL. METHODS: Cross-sectional analysis was performed, using data from VMAX, a cohort of people who use methamphetamine at least monthly in Victoria, Australia (n = 194). Utilising the oral health impact profile (OHIP-14), we assessed three OHRQoL outcomes: OHIP-14 prevalence, OHIP-14 extent and OHIP-14 severity. Regression analyses examined associations between independent variables and the three OHIP-14 outcome measures. RESULTS: A significant segment of the cohort (35%) reported poor OHRQoL. Overall, no statistically significant association was detected between methamphetamine route of administration and the three OHIP-14 outcomes. Participants living in rural areas, with moderate-to-severe self-reported depression and with methamphetamine dependence had significantly worse OHRQoL levels, which persisted after adjusting for other covariates. CONCLUSION: Overall, VMAX cohort participants reported reduced OHRQoL levels. Our findings highlight the need for upstream interventions to improve the OHRQoL of people who use methamphetamine, with specific focus on those living in rural locations. Further research on the links between OHRQoL and mental health among people who use methamphetamine is required.

The eliminate hepatitis C (EC) experience study: baseline characteristics of a cohort of people who inject drugs in Melbourne, Australia.

OBJECTIVES: Direct-acting antivirals provide an opportunity to eliminate hepatitis C virus (HCV) as a public health threat in Australia, yet barriers to care remain. In this study, we use baseline data from a longitudinal cohort of people who inject drugs to understand differences in participant characteristics and explore experiences of stigma, health service utilisation and health literacy between three care cascade groups. DESIGN: Cross-sectional. SETTING: Community and private primary healthcare services in Melbourne, Australia. PARTICIPANTS: Participants completed baseline surveys between 19 September 2018 and 15 December 2020. We recruited 288 participants; the median age was 42 years (IQR: 37-49 years) and 198 (69%) were male. At baseline, 103 (36%) self-reported being 'not engaged in testing', 127 (44%) had HCV RNA positivity but were 'not engaged in treatment' and 58 (20%) were 'engaged in HCV treatment'. OUTCOME MEASURES: Descriptive statistics were used to present the baseline demographics, health service utilisation and experiences of stigma data. We explored differences in these scales between participant demographics using χ2 test or fisher's exact tests, and differences between health literacy scores using one-way analysis of variance tests. RESULTS: A majority were in regular contact with multiple health services, and most had previously been identified as at-risk of HCV. In the 12 months preceding baseline, 70% reported any experiences of stigma related to injecting drug use. Assessment of health literacy data identified gaps for those 'not engaged in testing' and 'not engaged in treatment' across two relevant domains: 'ability to appraise health information' and 'ability to actively engage with healthcare providers'. CONCLUSION: In eliminate hepatitis C experience, lower HCV testing and treatment may be explained by experiences of stigmatisation or gaps in health literacy. Enhanced interventions targeting people who inject drugs to promote HCV care are needed.