Expanding access to diacetylmorphine and hydromorphone for people who use opioids in Canada

'I don't chase drugs as much anymore, and I'm not dead': Client reported outcomes associated with safer opioid supply programs in Ontario, Canada

INTRODUCTION

The ongoing opioid overdose crisis, which has killed over 30,000 people in Canada since 2016, is driven by the volatility of an unregulated opioid drug supply comprised primarily of fentanyl. The Canadian government has recently funded safer opioid supply (SOS) programs, which include off-label prescriptions of pharmaceutical-grade opioids to high risk individuals with the goal of reducing overdose deaths.

METHODS

In 2021, we examined the implementation and adaption of four SOS programs in Ontario. These programs use a primary care model and serve communities experiencing marginalisation. We conducted semi-structured interviews with program clients. We present the results of a thematic analysis with the aim of describing clients' self-reported impact of these programs on their health and well-being.

RESULTS

We interviewed 52 clients between June and October 2021 (mean age 47 years, 56% men, 17% self-identified Indigenous, 14% living with HIV). Our results indicate multifaceted pathways to improved self-reported health and well-being among clients including changes to drug use practices, fewer overdoses, reduced criminalised activity, improved trust and engagement in health care, and increased social stability (e.g., housing).

DISCUSSION AND CONCLUSION

Most clients reported that the intervention saved their life because of the reduced frequency of overdoses. Findings suggest that SOS programs improved clients' health outcomes and increase opportunities for engagement in health services. Our results provide insight into the mechanisms behind some of the emergent evidence on the impact of safer supply prescribing.

People who inject oral morphine favor experimentation with injectable opioid substitution

BACKGROUND

The French Addictovigilance network has observed the existence of the intravenous use of oral morphine capsules among people suffering from opioid use disorders. According to persons who inject morphine, these capsules are easy to dissolve and then inject, giving them the image of an "injectable" opioid substitution treatment (OST). In France, validated OSTs are only available orally, so dissolving morphine capsules represents the only alternative for patients who are not sufficiently relieved by oral forms. This practice presents risks related to the potential persistence of particles of the oral galenic in the injectable solution, despite its filtration, but also risks-notably of overdose-related to the pharmacological effects of opioids and to variations of the quantities of morphine extracted during the dissolution of the capsules. We conducted an online survey among the people concerned to collect data on their needs and expectations regarding a possible injectable substitution.

METHOD

An anonymous online survey including all voluntary respondents residing in France and using oral morphine intravenously was conducted in partnership with the Psychoactif harm reduction organization, from 23/03/2020 to 01/04/2021.

RESULTS

The analysis of the 157 exploitable questionnaires showed that 41% of the respondents obtained their drugs only from illegal markets. The others received, regularly or occasionally, medical prescriptions, reimbursed in 84% of cases. For 78% of the respondents, injection was the most frequent route of morphine administration, with 3.8 ± 2 injections per day. 56% of the respondents were receiving an OST, on prescription (79%), monthly (86%), in addition to morphine. Skenan® capsules were the most frequently used (81%) and 47.2% of the respondents had already experienced injection-related complications. 95% of the respondents were in favor of experimenting with an injectable morphine substitution. Those who never received medical prescriptions were the youngest (< 25 years) respondents, they reported only occasional use of morphine, and always intravenously.

CONCLUSION

Oral morphine capsules dissolved and injected intravenously are not a safe and sustainable injectable substitution. Respondents wish to be able to benefit from an injectable substitution with a formulation adapted to the intravenous route. The availability of an injectable substitution would facilitate harm reduction and entry into care for the people concerned, particularly the youngest who have never received morphine prescriptions.

A Case report of a continuous ambulatory drug delivery (CADD) pump to deliver opioid agonist treatment in an acute care setting

BACKGROUND

People with substance use disorder are at risk of complications of drug use and frequent hospitalization and may continue to use substances during admission to acute care. Acute care harm reduction strategies including oral or injectable prescription opioids may aid in care retention and improve health outcomes in this patient population.

CASE PRESENTATION

A 58-year-old woman with refractory opioid use disorder was admitted to hospital for management of dysphagia secondary to esophageal stricture. She received injectable opioid agonist therapy using a continuous ambulatory drug delivery (CADD) pump in order to facilitate completion of her hospital admission.

CONCLUSIONS

The patient successfully received acute medical care with the use of a CADD pump for consistent, patient-controlled opioid administration, with the support of an interdisciplinary team and by respecting the patient's own substance use goals.

Perinatal Injectable Opioid Agonist Therapy (iOAT) Administration: A Case Series

OBJECTIVES

Untreated opioid use disorder (OUD) in pregnancy may lead to adverse outcomes for the individual and fetus. Injectable opioid agonist therapy (iOAT) is the highest intensity treatment for severe refractory OUD currently available; however, research on perinatal administration is limited. We present the first known case series of 13 pregnant or postpartum participants who received intravenous hydromorphone while admitted to the Families in Recovery (FIR) unit, an in-patient perinatal stabilization unit in Canada.

METHODS

Patients who received iOAT at FIR between 2019 and 2022 were invited to participate. Prospectively enrolled participants completed a self-report sociodemographics and exposures survey. Medical/social backgrounds of participants at admission, iOAT and other opioid agonist therapy administration, and health/social outcomes of mother and infant at discharge were collected on all participants via retrospective maternal and infant medical chart review.

RESULTS

Participants initiated iOAT while pregnant (n = 5) or postpartum (n = 8) and received iOAT for 23 days on average. At discharge, 8 participants underwent planned transition to community with infant in their care and a discharge plan including outpatient prescriptions, housing arrangements, follow-up appointments, and supportive programming. All infants received oral morphine after delivery and were discharged in good health.

CONCLUSIONS

This is the first known case series of iOAT administration in the peripartum. The cases illustrate iOAT as an option that can achieve OUD stabilization in perinatal individuals to support patient engagement and retention in care.

Impact of safer supply programs on injection practices: client and provider experiences in Ontario, Canada

OBJECTIVES

Fentanyl has contributed to a sharp rise in the toxicity of the unregulated drug supply and fatal overdoses in Canada. It has also changed injection practices. Injection frequency has increased as a result and so has equipment sharing and health-related risks. The aim of this analysis was to explore the impact of safer supply programs on injection practices from the perspective of clients and providers in Ontario, Canada.

METHODS

The data set included qualitative interviews with 52 clients and 21 providers that were conducted between February and October 2021 across four safer supply programs. Interview excerpts discussing injection practices were extracted, screened, coded and then grouped into themes.

RESULTS

We identified three themes, each theme corresponding to a change in injection practices. The first change was a decrease in the amount of fentanyl used and a decrease in injection frequency. The second change involved switching to injecting hydromorphone tablets instead of fentanyl. Finally, the third change was stopping injecting altogether and taking safer supply medications orally.

CONCLUSION

Safer supply programs can contribute to reducing injection-related health risks in addition to overdose risks. More specifically, they have the potential to address disease prevention and health promotion gaps that stand-alone downstream harm reduction interventions cannot address, by working upstream and providing a safer alternative to fentanyl.

Intravenous misuse of slow-release oral morphine capsules: how much morphine is injected?

BACKGROUND

The injection of morphine from morphine sulfate capsules containing sustained-release microbeads (Skenan®) is a practice frequently described by French intravenous opioid users. They seek an injectable form of substitution for heroin. Depending on how the syringe is prepared, the morphine rates may vary. The dosage of the capsule, the temperature of the dissolving water and the type of filter used have been identified as the parameters most likely to influence the final quantity of morphine in solution before intravenous injection. The aim of our study was to determine the amounts of morphine actually injected, according to the different preparation modalities described by people who inject morphine and the harm reduction equipment made available to them.

METHODS

Different morphine syringes were prepared by varying the dosage of the capsule (100 or 200 mg), the temperature of the dissolving water before adding morphine, ambient (≈ 22 °C) or heat (≈ 80 °C) and four filtration devices: risk reduction Steribox® cotton, risk reduction filter "Sterifilt®", "Wheel" filter and cigarette filter. The quantification of the morphine in the syringe body was carried out by liquid phase chromatography coupled with a mass spectrometry detector.

RESULTS

The best extraction yields were obtained with heated water, independently of dosages (p < 0.01). Yields of 100 mg capsules varied according to the filter (p < 0.01) and the water temperature (p < 0.01), with maximum yields obtained for solutions dissolved in heated water, then filtered with the "Wheel" filter (83 mg). The yields of the 200 mg capsules varied according to the temperature of the water (p < 0.01), without difference according to the filter used (p > 0.01), and maximum yields obtained for solutions dissolved in heated water (95 mg).

CONCLUSIONS

No procedure for dissolving Skenan® led to the complete dissolution of the morphine it contains. Whatever the variations in preparation conditions, the extraction rates of the 200 mg morphine capsules were lower than those of 100 mg, without the risk reduction filters adversely impacting morphine extraction. Offering an injectable substitution to persons who inject morphine would make it possible to reduce the risks and damage, particularly overdoses, associated with variations in dosage due to preparation methods.

Long-Term Stability of Hydromorphone in Human Plasma Frozen at −20°C for Three Years Quantified by LC-MS/MS

The long-term stability of drugs under normal laboratory storage conditions (−20°C) for years is important for research purposes, clinical re-evaluation, and also for forensic toxicology. To evaluate the stability of the analgesic opioid hydromorphone, 44 human frozen plasma samples of a former clinical trial were reanalyzed after at least three years. Blood samples were disposed using solid-phase extraction with an additional substitution of stable isotope labelled hydromorphone as an internal standard. Hydromorphone concentrations were determined by ultra-performance liquid chromatography (UPLC) with gradient elution, followed by tandem mass spectrometry with electrospray ionization. Calibration curves demonstrated linearity of the assay in the concentration range of 0.3–20 ng/mL hydromorphone. The limit of detection of the hydromorphone plasma concentration was 0.001 ng/mL, and the lower limit of quantification was 0.3 ng/mL. Intra- and interassay errors did not exceed 16%. The percentage deviation of the measured hydromorphone plasma concentrations between the reanalysis and the first analysis was −1.07% ± 14.8% (mean ± SD). These results demonstrate that hydromorphone concentration in human plasma was stable when the samples were frozen at −20°C over three years. This finding is of value for re-evaluations or delayed analyses for research purposes and in pharmacokinetic studies, such as in forensic medicine.

Endogenous opiates and behavior: 2020

This paper is the forty-third consecutive installment of the annual anthological review of research concerning the endogenous opioid system, summarizing articles published during 2020 that studied the behavioral effects of molecular, pharmacological and genetic manipulation of opioid peptides and receptors as well as effects of opioid/opiate agonists and antagonists. The review is subdivided into the following specific topics: molecular-biochemical effects and neurochemical localization studies of endogenous opioids and their receptors (1), the roles of these opioid peptides and receptors in pain and analgesia in animals (2) and humans (3), opioid-sensitive and opioid-insensitive effects of nonopioid analgesics (4), opioid peptide and receptor involvement in tolerance and dependence (5), stress and social status (6), learning and memory (7), eating and drinking (8), drug abuse and alcohol (9), sexual activity and hormones, pregnancy, development and endocrinology (10), mental illness and mood (11), seizures and neurologic disorders (12), electrical-related activity and neurophysiology (13), general activity and locomotion (14), gastrointestinal, renal and hepatic functions (15), cardiovascular responses (16), respiration and thermoregulation (17), and immunological responses (18).

Naloxone protection, social support, network characteristics, and overdose experiences among a cohort of people who use illicit opioids in New York City

Background

Despite increased availability of take-home naloxone, many people who use opioids do so in unprotected contexts, with no other person who might administer naloxone present, increasing the likelihood that an overdose will result in death. Thus, there is a social nature to being “protected” from overdose mortality, which highlights the importance of identifying background factors that promote access to protective social networks among people who use opioids.

Methods

We used respondent-driven sampling to recruit adults residing in New York City who reported recent (past 3-day) nonmedical opioid use (n = 575). Participants completed a baseline assessment that included past 30-day measures of substance use, overdose experiences, and number of “protected” opioid use events, defined as involving naloxone and the presence of another person who could administer it, as well as measures of network characteristics and social support. We used modified Poisson regression with robust variance to estimate unadjusted and adjusted prevalence ratios (PRs) and 95% confidence intervals (CIs).

Results

66% of participants had ever been trained to administer naloxone, 18% had used it in the past three months, and 32% had experienced a recent overdose (past 30 days). During recent opioid use events, 64% reported never having naloxone and a person to administer present. This was more common among those: aged ≥ 50 years (PR: 1.18 (CI 1.03, 1.34); who identified as non-Hispanic Black (PR: 1.27 (CI 1.05, 1.53); experienced higher levels of stigma consciousness (PR: 1.13 (CI 1.00, 1.28); and with small social networks (< 5 persons) (APR: 1.14 (CI 0.98, 1.31). Having a recent overdose experience was associated with severe opioid use disorder (PR: 2.45 (CI 1.49, 4.04), suicidality (PR: 1.72 (CI 1.19, 2.49), depression (PR: 1.54 (CI 1.20, 1.98) and positive urinalysis result for benzodiazepines (PR: 1.56 (CI 1.23, 1.96), but not with network size.

Conclusions

Results show considerable gaps in naloxone protection among people who use opioids, with more vulnerable and historically disadvantaged subpopulations less likely to be protected. Larger social networks of people who use opioids may be an important resource to curtail overdose mortality, but more effort is needed to harness the protective aspects of social networks.

Xylazine detected in unregulated opioids and drug administration equipment in Toronto, Canada: clinical and social implications

BACKGROUND

The North American opioid overdose crisis is driven in large part by the presence of unknown psychoactive adulterants in the dynamic, unregulated drug supply. We herein report the first detection of the psychoactive veterinary compound xylazine in Toronto, the largest urban center in Canada, by the city's drug checking service.

METHODS

Toronto's Drug Checking Service launched in October 2019. Between then and February 2021, 2263 samples were submitted for analysis. The service is offered voluntarily at harm reduction agencies that include supervised consumption services. Samples were analyzed using gas chromatography-mass spectrometry or liquid chromatography-high resolution mass spectrometry. Targeted and/or untargeted screens for psychoactive substances were undertaken.

RESULTS

In September 2020, xylazine was first detected by Toronto's Drug Checking Service. Among samples analyzed from September 2020 to February 2021 expected to contain fentanyl in isolation (610) or in combination with methamphetamine (16), xylazine was detected in 46 samples (7.2% and 12.5% of samples, respectively). Samples were predominantly drawn from used drug equipment. Three of the samples containing xylazine (6.5%) were associated with an overdose.

CONCLUSION

We present the first detection of xylazine in Toronto, North America's fourth-largest metropolitan area. The increased risk of overdose associated with use of xylazine and its detection within our setting highlights the importance of drug checking services in supporting rapid responses to the emergence of potentially harmful adulterants. These data also highlight the clinical challenges presented by the dynamic nature of unregulated drug markets and the concomitant need to establish regulatory structures to reduce their contribution to overdose morbidity and mortality.

Investigating a bidirectional relationship between overdose and provision of injection initiation assistance among persons who inject drugs in Vancouver, Canada and Tijuana, Mexico

BACKGROUND

Individuals who initiate injection drug use often receive assistance from an injection-knowledgeable peer. Persons who assist peers in injection initiation events often inject frequently, which heightens overdose risk. As such, overdose and injection initiation events may be correlated. To explore a potential relationship, we assessed temporal associations between experiencing a non-fatal overdose and assisting others in initiating injection drug use among persons who inject drugs in two North American cities - Vancouver, Canada and Tijuana, Mexico.

METHODS

From 2014 to 2018, this retrospective cohort study included people who inject drugs from Vancouver (n=1332) and Tijuana (n=666) who completed a baseline and six-month follow-up interview. Within each site, we assessed bidirectional temporal associations using two separate multivariable logistic regression models: for model 1, recent provision of injection initiation assistance (at six months) was the outcome and recent overdose (at baseline) was the exposure; for model 2, recent overdose (at six months) was the outcome and recent provision of injection initiation assistance (at baseline) was the exposure. Both models adjusted for potential confounders.

RESULTS

Vancouver-based participants reporting overdose at baseline had 163% greater odds of reporting provision of injection initiation assistance at follow-up (adjusted Odds Ratio [aOR] 2.63; 95% Confidence Interval [CI] 1.41-4.90); while participants reporting provision of injection initiation assistance at baseline had 89% greater odds of reporting a non-fatal overdose at follow-up (aOR 1.89; 95% CI 1.00-3.57). Among Tijuana-based participants, we did not observe a statistically significant association in either direction.

CONCLUSION

Findings in Vancouver suggest that injection initiation assistance and overdose are bidirectionally-associated phenomena. The present findings highlight the need for interventions that ensure that persons who provide injection initiation assistance are given overdose prevention support, both for themselves and for those they assist to initiate injection drug use. While our Tijuana-based results did not suggest a bidirectional relationship, preventative approaches should nonetheless be undertaken.

"I wanted to close the chapter completely … and I feel like that [carrying naloxone] would keep it open a little bit": Refusal to carry naloxone among newly-abstinent opioid users and 12-step identity

BACKGROUND

12-step programs aim to address drug-related harms, like opioid overdose, via abstinence. However, abstaining from opioids can diminish tolerance, which increases risk for overdose death upon resumption. A recent study found that desire to abstain from drugs inhibited willingness to participate in take-home naloxone programming, which was linked to perceptions of harm reduction strategies being tied to drug use. In the present study, we uncovered a similar phenomenon occurring among newly-abstinent participants who were refusing to carry naloxone.

METHODS

This study is an analysis of broader qualitative data collected throughout Southern California among persons who use opioids, including those recently abstinent. Preliminary analysis revealed that those newly abstinent refused to accept naloxone at the end of interviews, and so we began probing about this (N=44). We used thematic analysis and author positionality to explicate the emergent phenomenon and applied social identity theory to conceptualize findings.

RESULTS

Mechanisms underlying naloxone refusal included its tie to a drug-using identity that newly-abstinent participants were attempting to retire. Carrying naloxone was also viewed as pointless due to doubt of witnessing an overdose again. Furthermore, the thought of being equipped with naloxone was not believed to be congruent with an abstinent identity, e.g. "me carrying it [naloxone] is making me feel like I'm going to be hanging out with people that are doing it [using drugs]."

CONCLUSION

Recent detoxification heightens vulnerability to overdose, which other newly-abstinent peers might be positioned to respond to as bonds are formed through 12-step identity formation. However, naloxone is often refused by this group due to perceived 12-step identity clash. While some treatment spaces distribute naloxone, 12-step identity associated behavioral expectations appear to conflict with this strategy. Reframing these disconnects is essential for expanding the lifesaving naloxone community safety net.

A multi-methods and longitudinal study of patients' perceptions in injectable opioid agonist treatment: Implications for advancing patient-centered methodologies in substance use research

BACKGROUND

Patients' perceptions are vital to the delivery and evaluation of substance use treatment. They are most frequently collected at one time-point and measured using patient satisfaction questionnaires or qualitative methodologies. Interestingly, the findings of these studies often diverge, as satisfaction scores tend to be highly positive, while qualitative findings suggest dissatisfaction and areas for improvement. This divergence limits current understandings of patients' perceptions and their potential change over time in treatment.

OBJECTIVE

This study explores the relationship between open-ended positive and negative perceptions of treatment and patient satisfaction scores over time.

METHODS

The RUTH (Research on the Utilization of Therapeutic Hydromorphone) prospective cohort study included 131 participants receiving injectable diacetylmorphine or hydromorphone in Canada's first injectable opioid agonist treatment (iOAT) program. The study collected the Client Satisfaction Questionnaire (CSQ-8) at eight time-points over an 18-month period. Following a multi-methods approach, the study complemented the CSQ-8 with open-ended positive and negative comments of iOAT. The research team analyzed these comments thematically at each time-point to develop positive and negative perception themes. We then used growth curve modeling to explore the relationship between positive and negative perception themes and patient satisfaction over time.

FINDINGS

Over the eight time-points, six positive and eight negative perception themes emerged, broadly reflecting structural (e.g., expansion of iOAT), process (e.g., schedules), relational (e.g., interactions with providers), and outcome-related (e.g., met/unmet needs) perceptions of iOAT. On average, participants reported high satisfaction (grand mean = 29.2 out of 32), and scores did not significantly change over time. However, we did find significant unexplained variation within participants in their satisfaction trajectories and between participants in their initial satisfaction scores. In conditional growth curve models, the theme "unfavorable interactions with providers" had the strongest independent effect on overall satisfaction trajectories.

CONCLUSIONS

This study provides an example of how open-ended comments can be integrated with patient satisfaction questionnaire data to gather a comprehensive and patient-centered evaluation of substance use treatment. Considering the iOAT context specifically, relational dynamics and daily treatment access were significant predictors of patient satisfaction over time and may be attributes of iOAT that require further investigation.

Take home injectable opioids for opioid use disorder during and after the COVID-19 Pandemic is in urgent need: a case study

Background

In North America the opioid poisoning crisis currently faces the unprecedented challenges brought by the COVID-19 pandemic, further straining people and communities already facing structural and individual vulnerabilities. People with opioid use disorder (OUD) are facing unique challenges in response to COVID-19, such as not being able to adopt best practices (e.g., physical distancing) if they’re financially insecure or living in shelters (or homeless). They also have other medical conditions that make them more likely to be immunocompromised and at risk of developing COVID-19. In response to the COVID-19 public health emergency, national and provincial regulatory bodies introduced guidance and exemptions to mitigate the spread of the virus. Among them, clinical guidance for prescribers were issued to allow take home opioid medications for opioid agonist treatment (OAT). Take Home for injectable opioid agonist treatment (iOAT) is only considered within a restrictive regulatory structure, specific to the pandemic. Nevertheless, this risk mitigation guidance allowed carries, mostly daily dispensed, to a population that would not have access to it prior to the pandemic. In this case it is presented and discussed that if a carry was possible during the pandemic, then the carry could continue post COVID-19 to address a gap in our approach to individualize care for people with OUD receiving iOAT.

Case presentation

Here we present the first case of a patient in Canada with long-term OUD that received take home injectable diacetylmorphine to self-isolate in an approved site after being diagnosed with COVID-19 during a visit to the emergency room where he was diagnosed with cellulitis and admitted to receive antibiotics.

Conclusion

In the present case we demonstrated that it is feasible to provide iOAT outside the community clinic with no apparent negative consequences. Improving upon and making permanent these recently introduced risk mitigating guidance during COVID-19, have the potential not just to protect during the pandemic, but also to address long-overdue barriers to access evidence-based care in addiction treatment.

Service delivery models for injectable opioid agonist treatment in Canada: 2 sequential environmental scans

BACKGROUND

Injectable opioid agonist treatment (iOAT) is an emerging evidence-based option in the continuum of care for opioid use disorder in parts of Canada. Our study objective was to identify and describe iOAT programs operating during the ongoing opioid overdose crisis.

METHODS

We conducted 2 sequential environmental scans. Programs were eligible to participate if they were in operation as of Sept. 1, 2018, and Mar. 1, 2019. Information was collected over 2-3 months for each scan (September-October 2018, March-May 2019). Programs that participated in the first scan and newly established programs were invited to participate in the second scan. The scans included questions about location, service delivery model, clinical and operational characteristics, numbers and demographic characteristics of clients, and program barriers and facilitators. Descriptive analysis was performed.

RESULTS

We identified 14 unique programs across the 2 scans. Eleven programs located in urban centres in British Columbia and Ontario participated in the first scan. At the time of the second scan, 2 of these programs were on hold and 2 of 3 newly established programs were in Alberta. The total capacity of all participating programs was 420 clients at most. Four service delivery models were identified; iOAT was most commonly integrated within existing health and social services. All programs offered hydromorphone, and 1 program also offered diacetylmorphine. In the first scan, 73% of clients (133/183) were male; the mean age of clients was 47 years. Limited capacity, pharmacy operations and lack of diacetylmorphine access were among the most frequently reported barriers. The most commonly reported facilitators included client-centred care, client relationships and access to other health and social support.

INTERPRETATION

Evidence indicates that iOAT can be successfully implemented using diverse service delivery models. Future work should facilitate scale-up of this evidence-based treatment where gaps persist in high-risk communities.

Supervised consumption service use and recent non-fatal overdose among people who inject drugs in Toronto, Canada

BACKGROUND

Aiming to reducing overdose mortality, over 40 supervised drug consumption services (SCS) presently operate in Canada. Arguments against SCS include the potential for increased non-fatal overdoses mediated by risk compensation. This study estimates associations between SCS use and recent non-fatal overdose among people who inject drugs (PWID).

METHODS

We analyzed cross-sectional baseline data collected between November 2018 and March 2020 from a cohort of adult PWID in Toronto, Canada. Recent non-fatal overdose was self-reported over the previous six months. The primary exposure was frequency of SCS use, self-reported as the proportion of injections performed at an SCS (all or most [75-100%], some [26-74%], few [≤25%], or none) in the previous six months. The prevalence of recent overdose was compared between all unique pairs of groups based on their frequency of SCS use and expressed as covariate-adjusted prevalence ratios (PR) estimated using modified Poisson regression.

RESULTS

Among 701 PWID (median [IQR] age, 40 [33 to 49]; 64.3% cisgender men; 56.8% injecting daily), most reported SCS use (all/most, 26.2%; some, 30.9%; few, 29.4%) versus no use (13.5%), with 38.6% reporting a recent overdose. From adjusted regression analyses, more frequent SCS use was not statistically significantly associated with overdose when compared to either no SCS use or less frequent use. Associations between SCS use frequency and overdose were notably smaller among SCS clients compared to associations between SCS clients and non-users (e.g., all/most versus none: PR, 1.43 [95% CI, 0.93 to 2.21]; all/most versus some: PR, 0.94 [95% CI, 0.75 to 1.17]; all/most versus few: PR, 1.15 [95% CI, 0.89 to 1.48]).

CONCLUSION

Findings did not indicate statistically significant associations between SCS use frequency and recent non-fatal overdose, particularly among SCS clients who may be more comparable. Nevertheless, overdose was common, underscoring the need to prevent non-fatal overdose and associated morbidity.

Motivations to initiate injectable hydromorphone and diacetylmorphine treatment: A qualitative study of patient experiences in Vancouver, Canada

BACKGROUND

Within the context of the ongoing overdose crisis and limitations of conventional opioid treatments, the scale-up of injectable hydromorphone (HDM) and diacetylmorphine (DAM) as evidenced-based treatments is currently underway in some settings in Canada. Past research has underscored the importance of treatment initiation in shaping onward treatment trajectories, however structural factors that influence participants' motivations to access injectable HDM or DAM have not been fully characterized. This study examines peoples' motivations for accessing HDM/DAM treatment and situates these within the social and structural context that shapes treatment delivery by employing the concept of structural vulnerability.

METHODS

Fifty-two individuals enrolled in injectable HDM/DAM programs were recruited from four community-based clinical programs in Vancouver, Canada to participate in qualitative semi-structured interviews. Approximately 50 h of ethnographic fieldwork was also completed in one clinical setting, and one-on-one with participants public spaces. Interview transcripts and ethnographic fieldnotes were analyzed through a structural vulnerability lens with a focus on treatment initiation.

RESULTS

Participants' previous experiences and perceptions of other drug treatments (e.g. methadone) foregrounded their initiation of injectable HDM/DAM. Social and structural factors (e.g. fentanyl-adulterated drug supply, poverty, drug criminalization) influenced participants' motivations to address immediate physical risks and their initial perception of this treatment's ability to align with their opioid use experiences. Similar social and structural factors that drive immediate physical risks, were also evidenced in participants' motivations to make changes in their daily lives and to address broader opioid use goals.

CONCLUSION

Participants descriptions of their motivations to initiate HDM/DAM highlight how structural vulnerabilities shaped participants' experiences initiating injectable HDM/DAM.