Trajectories of retention in opioid agonist therapy in a Canadian setting

Examining inequities in access to opioid agonist treatment (OAT) take-home doses (THD): A Canadian OAT guideline synthesis and systematic review

BACKGROUND

Daily supervised Opioid Agonist Treatment (OAT) medication has been identified as a barrier to treatment retention. Canadian OAT guidelines outline take-home dose (THD) criteria, yet, OAT prescribers use their clinical judgement to decide whether an individual is 'clinically stable' to receive THD. There is limited information regarding whether these decisions may result in inequitable access to THD, including in the context of updated COVID-19 guidance. The current Canadian OAT THD guideline synthesis and systematic review aimed to address this knowledge gap.

METHODS

This systematic review included a two-pronged approach. First, we searched available academic literature in Embase, Medline, and PsychINFO up until October 12th, 2022, to identify studies that compared characteristics of individuals on OAT who had and had not been granted access to THD to explore potential inequities in access. Next, we identified all Canadian national and provincial OAT guidelines through a semi-structured grey literature search (conducted between September-October 2022) and extracted all THD 'stability' and allowances/timeline criteria to compare against characteristics identified in the literature search. Data from both review arms were synthesized and narratively presented.

RESULTS

A total of n = 56 guidelines and n = 7 academic studies were included. The systematic review identified a number of patient characteristics such as age, sex, race/ethnicity, marital status, housing, employment, neighborhood income, drug use, mental health, health service utilization, as well as treatment duration that were associated with differential access to THD. The Canadian OAT THD guideline synthesis identified many of these same characteristics as 'stability' criteria, underscoring the potential for Canadian OAT guidelines to result in inequitable access to THD.

CONCLUSIONS

This two-pronged literature review demonstrated that current guidelines likely contribute to inequitable OAT THD access due primarily to inconsistent 'stability' criteria across guidelines. More research is needed to understand differential OAT THD access with a focus on prescriber decision-making and evaluating associated treatment and safety outcomes. The development of a client-centered, equity-focused, and evidence-informed decision making framework that incorporates more clear definitions of 'stability' criteria and indications for prescriber discretion is warranted.

"And this is the life jacket, the lifeline they've been wanting": Participant perspectives on navigating challenges and successes of prescribed safer supply

BACKGROUND

In 2021, 43% of drug toxicity deaths in Ontario were reported by public health units serving medium-sized urban and rural communities. Safer supply programs (SSPs) have been primarily established in large urban centres. Given this, the current study is based on an evaluation of a SSP based in a medium-sized urban centre with a large catchment area that includes rural and Indigenous communities. The aim of this research paper is to understand the challenges and successes of the nurse practitioner-led SSP from the perspective of program participants.

METHODS

Interpretive description was used to understand the experiences of 14 participants accessing a SSP. Each participant was interviewed using a semi-structured approach, and 13 of the interviewees also completed surveys accessed through Qualtrics. An iterative process using NVivo software was used to code interviews, and a constant comparative data analysis approach was used to refine and categorize codes to themes.

FINDINGS

Three overarching themes were the result of this analysis: feeling better, renewed hope, and safety. These three themes capture the experiences of participants in the SSP, including both the challenges and successes they faced.

CONCLUSION

The findings and subsequent discussion focus on both the key best practices of the program, and areas for future development and improvement. Despite barriers to services, prescribed SSPs are improving the lives of people who use drugs, and the current outcomes align with reports and evaluations from other SSPs across Canada.

Longitudinal polysubstance use patterns and non-fatal overdose: A repeated measures latent class analysis

BACKGROUND

Polysubstance use (PSU) is common among people who use opioids (PWUO) and has been associated with drug-related harms. We aimed to identify latent longitudinal PSU classes among a cohort of PWUO and characterize non-fatal overdose risks among different sub-classes over time.

METHODS

We used longitudinal data (2005-2018) from three ongoing prospective cohorts of people who use drugs in Vancouver, Canada. The primary outcome of interest was self-reported non-fatal overdose during the past six months. The primary exposure of interest was longitudinal PSU patterns among PWUO, obtained from repeated measures latent class analysis (RMLCA) of weekly substance use-related outcome indicators. Multivariable generalized estimating equations models were built to assess the association between latent PSU class membership and non-fatal overdose, adjusting for potential sociodemographic, behavioural, and structural confounders.

RESULTS

2627 PWUO were included in the analysis, and 1094 (41.6 %) had experienced at least one non-fatal overdose during the study period. RMLCA revealed five distinct latent longitudinal PSU classes, including low/infrequent use (Class 1; 30 %), primarily opioid and methamphetamine use (Class 2; 22 %), primarily cannabis use (Class 3; 15 %), primarily opioid and crack use (Class 4; 29 %), and frequent PSU (Class 5; 4 %). In comparison with Class 1 (low), membership in all latent PSU classes except Class 3 (cannabis) was associated with increased odds of non-fatal overdose: Class 2 (opioids + meth) vs. Class 1 (Adjusted odds ratios [aOR] = 2.20, 95 % confidence intervals [CI]: 1.51-3.22), Class 4 (opioids + crack) vs. Class 1 (aOR = 1.06, 95 % CI: 0.85-1.33), and Class 5 (frequent) vs. Class 1 (aOR = 2.39, 95 % CI: 1.92-2.97).

CONCLUSION

Our findings highlighted the heterogeneous characteristics of PWUO in terms of patterns of PSU and non-fatal overdose risk. The diverse nature of PWUO and the potential additive or multiplicative impact of using several substances on overdoses should be reflected across the substance use treatment continuum and care provision.

Correlates of nonfatal overdose among treatment-seeking individuals with non-heroin opioid use disorder: Findings from a pragmatic, pan-Canadian, randomized control trial

INTRODUCTION

Misuse of prescription and synthetic opioids is a primary contributor to the escalating overdose crisis in North America. However, factors associated with nonfatal overdose (NFO) in this context are poorly understood. We examined individual and socio-structural level correlates of NFO among treatment-seeking adults with an opioid use disorder (OUD) not attributed to heroin (nonheroin opioid use disorder [NH-OUD]).

METHODS

The study drew data from OPTIMA, a pan-Canadian, multicenter, pragmatic, two-arm randomized control trial comparing supervised methadone and flexible take-home dosing buprenorphine/naloxone models of care among adults with NH-OUD conducted between 2017 and 2020. We used bivariable and multivariable logistic regression to determine factors associated with a lifetime history of NFO among participants enrolled in the trial.

RESULTS

Of 267 included participants, 154 (58%) reported a NFO in their lifetime, of whom 83 (55 %) had an NFO in the last 6 months. In multivariable analyses, positive urine drug test (UDT) for methamphetamine/amphetamine (Adjusted Odds Ratio [AOR] = 2.59; 95 % confidence interval [CI]: 1.17-5.80), positive UDT for fentanyl (AOR = 2.31; 95 % CI: 1.01-5.30), receiving income assistance (AOR = 2.17; 95 % CI: 1.18-4.09) and homelessness (AOR = 2.40; 95 % CI: 1.25-4.68) were positively associated with a lifetime history of NFO.

CONCLUSIONS

We found a high prevalence of NFO history in treatment-seeking adults with NH-OUD, particularly among participants with certain drug use patterns and markers of socio-structural marginalization at the time of enrollment. Given the known impact of prior NFO on future harms, these findings highlight the need for comprehensive care approaches that address polysubstance use and social determinants of health to mitigate future overdose risk.

The Impact of Later Life Events on Cessation Motivation of Older Adults with Substance Use Disorder in Hong Kong

Life-course researchers have found that age-graded life events, such as marriage and employment, may provoke a turning point in the trajectories of substance use and motivate young adults with substance use disorder (SUD) to seek addiction treatment and cease illegal drug use. However, few studies have focused on the impact of the life events experienced by older adults with SUD in their later life on these trajectories. Even less is known about this phenomenon in non-Western contexts. Thus, we conducted interviews with 34 older individuals with SUD in Hong Kong and explored how later life events affected their motivation to cease illegal drug use. Our findings highlight the influence of age on how life events are experienced and the need for age-specific academic studies of substance use trajectories. The results also have implications for policymakers, as the criminalization and stigmatization of drug use may have a negative impact on the trajectories of substance use among older populations.

Long-term patterns of treatment use for opioid use disorder (OUD): Findings from the 18-20-year Australian Treatment Outcome Study

BACKGROUND

Opioid-related deaths continue to increase to unprecedented rates in many regions of the world. While long-term stable treatment has been shown to reduce associated morbidity and mortality, discontinuation and numerous treatment episodes are common, limiting our understanding of the common course of treatment and associated characteristics. Therefore, using an 18-20-year follow-up of people with heroin dependence, we aimed to identify i) distinct trajectories of treatment use, ii) whether baseline characteristics predict treatment trajectory group membership, and ii) if group membership is associated with characteristics at 18-20-years post-baseline.

METHODS

A total of 615 people with heroin dependence were recruited from maintenance therapy, detoxification, residential rehabilitation, or needle and syringe programs as part of the Australian Treatment Outcome Study (ATOS), a longitudinal cohort followed up on seven occasions over 18-20-years between 2001 and 2021. Of those who had complete data (n = 393), group-based trajectory modelling and a series of multinomial logistical regressions were conducted.

RESULTS

Five trajectories of treatment use were identified: i) 'long-term low treatment' (17.2%), ii) 'rapid increase with gradual decrease' (13.9%), iii) 'late increase' (17.8%), (iv) 'long-term treatment' (27.7%), and (v) 'reduced treatment' (23.5%). Entering maintenance treatment at baseline predicted trajectory group membership, while trajectory group membership was associated with demographics and the use of heroin, methamphetamine, alcohol, and benzodiazepines at 18-20-years.

CONCLUSIONS

In one of the longest cohort studies of its kind, we characterised distinct trajectories of treatment use in people with heroin dependence over 18-20-years. Clinicians should be aware of the potential impact of demographics and substance use on long-term treatment use. Despite the well-documented benefits of long-term treatment, some patients may be able to achieve abstinence from opioids without engaging in treatment over the life-course.

Characterizing opioid agonist therapy uptake and factors associated with treatment retention among people with HIV in British Columbia, Canada

Accidental overdoses are now the leading cause of death among people with HIV (PWH) in British Columbia (BC). We examined the utilization and retention of opioid agonist therapy (OAT). Adult PWH (≥19 years) with ≥ 1 OAT dispensation in BC between 2008 and 2020 were included (n = 1,515). OAT treatment episodes were formed based on specific criteria for slow-release oral morphine (SROM), methadone, injectable OAT (iOAT), and buprenorphine/naloxone. Retention in treatment was defined as any episode lasting ≥ 12 months. Logistic regression with generalized estimating equations modeled retention-associated factors. There was a 56.6% decline in OAT retention over time. Buprenorphine treatment exhibited significantly lower odds of retention (OR: 0.58; 95% CI: 0.36-0.92) compared to methadone. Conversely, no significant change in retention odds was observed for SROM (0.72; 0.33-1.54) and iOAT (0.81; 0.31-2.12). Factors associated with increased odds of retention included a 10-year increase in age (1.69; 1.46-1.95), previous retention history (1.96; 1.40-2.73), achieving OAT therapeutic dose (8.22; 6.67-10.14), and suppressed HIV viral load (1.35; 1.10-1.67). Individuals with a lifetime HCV diagnosis receiving iOAT were more likely to retain (3.61; 1.20-10.83). Each additional year on OAT during the study period was associated with a 4% increase in the odds of retention. A significant proportion of PWH had a history of OAT prescribing but experienced low retention rates. Retention outcomes were more positive for SROM and iOAT. The association between OAT medication type and retention odds may be particularly influenced by HCV diagnosis. Optimal management of opioid use disorder among PWH, with an emphasis on attaining the therapeutic dose is crucial.

The impact of relaxing restrictions on take-home doses during the COVID-19 pandemic on program effectiveness and client experiences in opioid agonist treatment: a mixed methods systematic review

BACKGROUND

The COVID-19 pandemic led to an unprecedented relaxation of restrictions on take-home doses in opioid agonist treatment (OAT). We conducted a mixed methods systematic review to explore the impact of these changes on program effectiveness and client experiences in OAT.

METHODS

The protocol for this review was registered in PROSPERO (CRD42022352310). From Aug.-Nov. 2022, we searched Medline, Embase, CINAHL, PsycInfo, Web of Science, Cochrane Register of Controlled Trials, and the grey literature. We included studies reporting quantitative measures of retention in treatment, illicit substance use, overdose, client health, quality of life, or treatment satisfaction or using qualitative methods to examine client experiences with take-home doses during the pandemic. We critically appraised studies using the Mixed Methods Appraisal Tool. We synthesized quantitative data using vote-counting by direction of effect and presented the results in harvest plots. Qualitative data were analyzed using thematic synthesis. We used a convergent segregated approach to integrate quantitative and qualitative findings.

RESULTS

Forty studies were included. Most were from North America (23/40) or the United Kingdom (9/40). The quantitative synthesis was limited by potential for confounding, but suggested an association between take-home doses and increased retention in treatment. There was no evidence of an association between take-home doses and illicit substance use or overdose. Qualitative findings indicated that take-home doses reduced clients' exposure to unregulated substances and stigma and minimized work/treatment conflicts. Though some clients reported challenges with managing their medication, the dominant narrative was one of appreciation, reduced anxiety, and a renewed sense of agency and identity. The integrated analysis suggested reduced treatment burden as an explanation for improved retention and revealed variation in individual relationships between take-home doses and illicit substance use. We identified a critical gap in quantitative measures of patient-important outcomes.

CONCLUSION

The relaxation of restrictions on take-home doses was associated with improved client experience and retention in OAT. We found no evidence of an association with illicit substance use or overdose, despite the expansion of take-home doses to previously ineligible groups. Including patient-important outcome measures in policy, program development, and treatment planning is essential to ensuring that decisions around take-home doses accurately reflect their value to clients.

Typology of laws restricting access to methadone treatment in the United States: A latent class analysis

BACKGROUND

In the United States, methadone treatment for opioid use disorder is only available at opioid treatment programs (OTPs). In addition to federal regulations, states can enact laws which shape access to OTPs. We aimed to define classes of states according to restrictiveness of state OTP laws and examine population characteristics associated with class membership.

METHODS

A set of laws was extracted from a database of statutes and regulations governing OTPs in 49 states and the District of Columbia as of June 2021. Latent class analysis of laws was used to estimate the probability of class membership for each state. Class-weighted multinomial logistic regression analysis assessed state-level correlates of class membership and adjusted Relative Risk Ratio (aRRR) and 95% confidence intervals (95%CI) were generated.

RESULTS

States (n = 50) were assigned to three classes; Class 1) High restrictiveness on patient experience, low restrictiveness on access to service (n = 13); Class 2) Medium restrictiveness on patient experience, high restrictiveness on access to service (n = 14); Class 3) Low restrictiveness on patient experience, low restrictiveness on access to service (n = 23). States with a higher probability of membership in Classes with higher restrictiveness had higher rates of unemployment (Class 1 vs Class 3, aRRR:1.24; 95%CI:1.06-1.45), and Black residents (Class 2 vs Class 3, aRRR:1.10; 95%CI:1.04-1.15), and lower likelihood of Medicaid coverage of methadone (Class 1 vs Class 3, aRRR:0.25; 95%CI:0.07-0.88). States with a higher probability of membership in Classes with higher restrictiveness also had higher rates of potential indicators for opioid use disorder treatment need, including rates of opioid dispensing (Class 1 vs Class 3, aRRR:1.06; 95%CI:1.02-1.10, Class 2 vs Class 3, aRRR:1.07; 95%CI:1.03-1.11) and HIV diagnoses attributed to injection (Class 1 vs Class 3, aRRR:3.92; 95%CI:1.25-12.22).

CONCLUSIONS

States with indicators of greater potential need for opioid use disorder treatment have the most restrictions, raising concerns about unmet treatment need.

The impact of methamphetamine use on medications for opioid use disorder (MOUD) treatment retention: a scoping review

BACKGROUND

An emerging public health threat of methamphetamine/opioid co-use is occurring in North America, including increases in overdoses related to concomitant methamphetamine/opioid use. This presents a potential risk to established treatments for opioid use disorder (i.e., medications for opioid use disorder [MOUD]). To date, few studies have examined the impact of methamphetamine use on MOUD-related outcomes, and no studies have synthesized data on MOUD retention.

METHODS

A scoping review was undertaken to examine the impact of methamphetamine use on MOUD retention. All original published research articles were searched in Embase, MEDLINE, PsychINFO, CINAHL, Scopus, Cochrane Central Register of Controlled Trials, Cochrane Database of Systematic Reviews and Cochrane Protocols, and Google scholar databases. Data were extracted into a standardized data extraction chart. Findings were presented narratively.

RESULTS

All eight included studies demonstrated an increased likelihood of treatment discontinuation or dropout among patients enrolled in MOUD who used methamphetamine. The frequency of methamphetamine use was also associated with MOUD dropout, in that those who used methamphetamine more often were more likely to discontinue MOUD. The definitions and measurements of MOUD retention varied considerably, as did the magnitude of effect size.

CONCLUSIONS

Results indicate that methamphetamine use has an undesirable impact on MOUD retention and results in an increased risk of treatment discontinuation or dropout. Strategies to identify concurrent methamphetamine use among individuals engaging in MOUD and educate them on the increased risk for dropout should be undertaken. Further research is needed to understand how MOUD retention among patients with concomitant opioid and methamphetamine use can be improved.

Trajectories of drug treatment and illicit opioid use in the AIDS Linked to the IntraVenous Experience cohort, 2014-2019

BACKGROUND

Medication for opioid use disorder (MOUD) is an effective intervention to combat opioid use disorder and overdose, yet there is limited understanding of engagement in treatment over time in the community, contextualized by ongoing substance use. We aimed to identify concurrent trajectories of methadone prescriptions, buprenorphine prescriptions, and illicit opioid use among older adults with a history of injection drug use.

METHODS

We used data on 887 participants from the AIDS Linked to the IntraVenous Experience cohort, who were engaged in the study in 2013 and attended ≥1 visit during follow-up (2014-2019). Outcomes were self-reported MOUD prescription and illicit opioid use in the last 6 months. To identify concurrent trajectories in all 3 outcomes, we used group-based multi-trajectory modeling. We examined participant characteristics, including sociodemographics, HIV status, and other substance use, overall and by cluster.

RESULTS

We identified 4 trajectory clusters: (1) no MOUD and no illicit opioid use (43%); (2) buprenorphine and some illicit opioid use (11%); (3) methadone and no illicit opioid use (28%); and (4) some methadone and illicit opioid use (18%). While prevalence of each outcome was stable across time, transitions on/off treatment or on/off illicit opioid use occurred, with the rate of transition varying by cluster. The rate of transition was highest in Cluster 3 (0.74/person-year) and lowest in Cluster 1 (0.18/person-year). We saw differences in participant characteristics by cluster, including that the buprenorphine cluster had the highest proportion of people with HIV and participants who identified as non-Hispanic Black.

CONCLUSIONS

Most participants had discontinued illicit opioid use and were also not accessing MOUD. Trajectories defined by engagement with buprenorphine or methadone had distinct sociodemographic and behavioral characteristics, indicating that tailored interventions to expand access to both types of treatment are likely needed to reduce harms associated with untreated opioid use disorder.

Outpatient Rapid Titration of Slow Release Oral Morphine for the Treatment of Opioid Use Disorder in a Canadian Setting: A Case Series

INTRODUCTION

In the midst of unprecedented opioid overdose deaths, opioid agonist therapy induction strategies that allow for rapid titration to therapeutic doses for individuals at high risk of overdose are needed. Slow release oral morphine (SROM) is an effective treatment for opioid use disorder; however, current guideline-recommended titration strategies require weeks to achieve therapeutic dose for individuals with high opioid tolerance. Individuals may be lost to care or experience overdose due to ongoing use of unregulated opioids during this time. After years of experience titrating SROM doses rapidly in the inpatient setting, we developed a protocol using short-acting morphine (MOS) to allow for rapid SROM titration in the outpatient setting.

CASES

Patients (n = 4) were eligible if they met the criteria for opioid use disorder and had evidence of high opioid tolerance. Patients received supervised MOS doses in the outpatient setting, which were consolidated into a 12-hour extended-release morphine dose (to a maximum of 500 mg) on the evening of the titration. The total titration-day MOS and 12-hour extended-release morphine were summed into the post-titration-day SROM dose, to a maximum of 1000 mg.

DISCUSSION

In the cases described, substantial reductions in unregulated fentanyl use and social gains, such as obtaining housing, employment, and enrollment in inpatient treatment programs, were observed after rapid SROM titration. No overdoses occurred during rapid SROM titration or during SROM treatment. More research is needed to determine the role for rapid SROM titrations as a stabilization option for outpatients.

Evaluation of the gap in delivery of opioid agonist therapy among individuals with opioid-related health problems: a population-based retrospective cohort study

AIMS

Although opioid-related harms have reached new heights across North America, the size of the gap in opioid agonist therapy (OAT) delivery for opioid-related health problems is unknown in most jurisdictions. This study sought to characterize the gap in OAT treatment using a cascade of care framework, and determine factors associated with engagement and retention in treatment.

DESIGN

A population-based retrospective cohort study.

SETTING

Ontario, Canada.

PARTICIPANTS

Individuals who sought medical care for opioid-related health problems or died from an opioid-related cause between 2005 and 2019.

MEASUREMENTS

Monthly treatment status for buprenorphine/naloxone or methadone OAT between 2013 and 2019 (i.e. 'off OAT', 'retained on OAT < 6 months', 'retained on OAT ≥ 6 months').

FINDINGS

Of 122 811 individuals in the cohort, 97 516 (79.4%) received OAT at least once during the study period. There was decreasing 6-month treatment retention over time. Model results indicated that males had higher odds of being on OAT each month [odds ratio (OR) = 1.26, 95% confidence interval (CI) = 1.23-1.28] but lower odds of OAT retention (OR = 0.90, 95% CI = 0.88-0.92), while the reverse was observed for older individuals (monthly: OR = 0.76 per 10-year increase, 95% CI = 0.76-0.77; retention: OR = 1.36 per 10-year increase, 95% CI = 1.34-1.38) and individuals with higher neighbourhood income (e.g. highest income quintile, monthly: OR = 0.79, 95% CI = 0.77-0.82; highest income quintile, retention: OR = 1.15, 95% CI = 1.11-1.20). Individuals residing in rural areas and with a history of mental health diagnoses had poorer outcomes overall, including lower odds of being on OAT each month (rural: OR = 0.75, 95% CI = 0.73-0.78; mental health: OR = 0.89, 95% CI = 0.87-0.92) and OAT retention (rural: OR = 0.79, 95% CI = 0.77-0.82; mental health: OR = 0.81, 95% CI = 0.78-0.83), as well as higher risk of starting/stopping OAT [rural, starting OAT: hazard ratio (HR) = 1.07, 95% CI = 1.05-1.10; mental health, starting OAT: HR = 1.20, 95% CI: 1.18-1.23; rural, stopping OAT: HR = 1.24, 95% CI: = 1.22-1.26; mental health, stopping OAT: HR = 1.11, 95% CI = 1.09-1.13]. Individuals with a history of mental health diagnoses also had a higher risk of death, regardless of OAT status (off OAT death: HR = 1.49, 95% CI = 1.33-1.66; on OAT death: HR = 1.20, 95% CI = 1.09-1.31).

CONCLUSIONS

Factors influencing engagement and declining retention in treatment with opioid agonist therapy in Ontario's health system include age, sex and neighbourhood income, as well as mental health diagnoses or residing in rural regions.

The increase in benzodiazepine-laced drugs and related risks in Canada: The urgent need for effective and sustainable solutions

The overdose crisis in Canada has continuously evolved and is increasingly challenging to contain, while efforts from governments and policymakers to address it have often fallen short and resulted in unintended consequences. One of the main repercussions has been an unprecedented rise in adulterants in the illegal drug supply, including a wide array of pharmacological and psychoactive compounds and chemicals, which has resulted in a progressively toxic drug supply. Most recently, there has been a stark increase in synthetic benzodiazepine-laced opioids (i.e., 'benzodope') in some Canadian jurisdictions. This unique combination carries distinct and amplified risks for people who use drugs including fatal and non-fatal overdoses, increased dependence and withdrawal symptoms, and places them in extremely vulnerable positions. The emergence of benzodiazepines within the illicit drug supply has substantially contributed to drug-related morbidity and mortality in Canada, and has further complicated current public health initiatives and overdose prevention efforts. This reality underscores the need for effective and sustainable policy solutions to address the evolving overdose epidemic including increased knowledge and education on the specific harms of opioid and benzodiazepine co-use (especially in regards to the complexity of opioid/benzodiazepine overdoses), scaling-up harm reduction measures, and eliminating the toxic drug supply altogether.

Acceptability, feasibility, and outcomes of a clinical pilot program for video observation of methadone take-home dosing during the COVID-19 pandemic

BACKGROUND

Methadone is one of the most utilized treatments for opioid use disorder. However, requirements for observing methadone dosing can impose barriers to patients and increase risk for respiratory illness transmission (e.g., COVID-19). Video observation of methadone dosing at home could allow opioid treatment programs (OTPs) to offer more take-home doses while ensuring patient safety through remote observation of ingestion.

METHODS

Between April and August 2020, a clinical pilot program of video observation of methadone take-home dosing via smartphone was conducted within a multisite OTP agency. Participating patients completed a COVID-19 symptom screener and submitted video recordings of themselves ingesting all methadone take-home doses. Patients who followed these procedures for a two-week trial period could continue participating in the full pilot program and potentially receive more take-home doses. This retrospective observational study characterizes patient engagement and compares clinical outcomes with matched controls.

RESULTS

Of 44 patients who initiated the two-week trial, 33 (75 %) were successful and continued participating in the full pilot program. Twenty full pilot participants (61 %) received increased take-home doses. Full pilot participants had more days with observed dosing over a 60-day period than matched controls (mean = 53.2 vs. 16.6 days, respectively). Clinical outcomes were similar between pilot participants and matched controls.

CONCLUSIONS

Video observation of methadone take-home dosing implemented during the COVID-19 pandemic was feasible. This model has the potential to enhance safety by increasing rates of observed methadone dosing and reducing infection risks and barriers associated with relying solely on face-to-face observation of methadone dosing.

Shifts in substance use patterns among a cohort of people who use opioids after delisting of OxyContin in BC, Canada: An interrupted time series study

BACKGROUND

OxyContin was delisted from Canadian provincial drug formularies in March 2012 and replaced with a reformulated tamper-resistant form of oxycodone (i.e., OxyNeo). We assessed if delisting of OxyContin was associated with changes in the use of unregulated opioids and other substances among people who use opioids (PWUO).

METHODS

Data were derived from two prospective cohort studies of people who use drugs in Vancouver, BC, Canada from 2006 to 2018. PWUO who had at least one follow-up visit before and after delisting of OxyContin were included. Outcomes of interest were self-reported regular (i.e., at least weekly) use of heroin, non-prescribed prescription opioids, cannabis, methamphetamine, crack cocaine, and powder cocaine during the previous six months. Using quasi-experimental interrupted time series, we fit generalized least squares models to assess participants' immediate and long-term substance use practices after the policy change.

RESULTS

We analyzed data from 1014 participants who contributed to 17457 visits during the study. Following the delisting of OxyContin, heroin use increased immediately by 5.17% (95% confidence intervals [CI]: 0.68 to 9.67) and over time by 0.47% (0.35 to 0.58) per month. Non-prescribed prescription opioid use increased immediately by 1.80% (0.10 to 3.50) and over time by 0.16% (0.12 to 0.19) per month. Cannabis use increased immediately by 4.37% (0.88 to 7.87) and over time by 0.11% (0.02 to 0.19) per month. Methamphetamine use did not increase immediately but increased over time by 0.10% (0.01 to 0.18) per month. Crack cocaine use decreased immediately by 6.13% (-10.94 to -1.69) but not significantly over time. Lastly, powder cocaine use did not increase immediately or over time.

CONCLUSIONS

Delisting of OxyContin in BC was not associated with a reduction in unregulated opioid use among PWUO. Our findings point to a shift in substance use patterns of PWUO post-intervention and further highlight the unintended consequences of supply-reduction interventions in addressing the opioid epidemic.

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).

Short communication: Relationship between social determinants and opioid use disorder treatment outcomes by gender

BACKGROUND

Social determinants of health (SDoH) influence health outcomes differentially across gender. Gender differences in SDoH have been identified at baseline in opioid use disorder (OUD) treatment studies, but less is known about how SDoH and gender intersect with OUD treatment trajectories. This study aims to identify social correlates of OUD treatment outcomes from five key areas of social determinants separately for men and women receiving buprenorphine for OUD.

METHODS

This is a secondary data analysis of a cross-sectional survey with medical record review conducted with patients recruited from an office based opioid treatment clinic. Participants completed surveys between July-September 2019. A 6-month prospective medical record review was conducted to determine treatment retention, substance use recurrence, and buprenorphine continuation. Chi square, T-tests, and Mann Whitney U tested differences in social factors and OUD outcomes by gender. Gender-stratified multivariable logistic and negative binomial regressions assessed predictors of OUD outcomes.

RESULTS

Among study participants (n = 142), women were significantly younger (p < 0.001), more likely to live in a safe neighborhood (p = 0.046), and less likely to be employed (p = 0.005) or have substance use recurrence during the study period (p = 0.033) than men. For women, employment (AOR=0.19, p = 0.031) and education (AOR=0.08, p = 0.040) were negatively associated with treatment retention. For men, no social factors were associated with OUD outcomes.

CONCLUSIONS

SDoH may impact OUD treatment outcomes differently by gender. Addressing MOUD stigma and implementing patient-centered care strategies may facilitate OUD treatment continuation among employed women in recovery. Gender-related social factors should be considered in OUD treatment research.

Assessing the determinants of completing OAT induction and long-term retention: A population-based study in British Columbia, Canada

BACKGROUND

Pharmacological treatments for opioid use disorder are essential, life-saving medications, yet successful induction of them and long-term retention on them is limited in many settings. Induction into opioid agonist treatment (OAT) features the highest risk of mortality throughout the treatment course, and greatest risk of discontinuation. We aimed to identify determinants of completing OAT induction and, among those completing induction, time to OAT discontinuation in British Columbia (BC), Canada.

METHODS

We conducted a retrospective study using linked population-level health administrative databases to capture all individuals in BC receiving at least one OAT dispensation from January 1, 2008, to September 30, 2018. We constructed covariates capturing client demographics, clinical history, and characteristics of the treatment episode and the primary prescribing physician. We estimated a two-part model to identify determinants of the probability of completing induction using a generalized linear mixed model with logit link and the time to OAT discontinuation among those completing induction using a Cox proportional hazards frailty model.

RESULTS

We observed 220,474 OAT episodes (73.9% initiated with methadone, 24.7% with buprenorphine, and 1.4% with slow-release oral morphine) among 45,608 individuals over the study period. Less than 60% of all OAT episodes completed induction (59.0% for methadone episodes, 56.7% for buprenorphine/naloxone, 41.0% for slow-release oral morphine) and half of all episodes that completed induction reached the minimum effective dosage (51.0% for methadone episodes [60 mg/day], 48.2% for buprenorphine/naloxone [12 mg/day], 59.4% for slow-release oral morphine [240 mg/day]). In multiple regression analysis, the adjusted odds of completing induction with buprenorphine improved over time, exceeding that of methadone in 2018: 1.46 (1.40, 1.51). For those who completed induction, buprenorphine use was associated with shorter times to discontinuation throughout the study period, but the estimated rate of discontinuation decreased over time (adjusted hazard ratio, vs. methadone in 2008: 2.50 (2.35, 2.66); in 2018: 1.79 (1.74, 1.85)).

CONCLUSION

We found low rates of completing OAT induction and, for those who did complete it, low rates of reaching the minimum effective dose.

Psychedelic use is associated with reduced daily opioid use among people who use illicit drugs in a Canadian setting

BACKGROUND

Research into the therapeutic and naturalistic uses of psychedelics for improving outcomes related to mental health disorders has generated increasing interest in recent years. While controlled clinical trials of psychedelics have signaled benefits for treating substance use disorders, this area has not been well studied in the context of naturalistic psychedelic use. This study sought to investigate the possible relationship between recent naturalistic psychedelic use and subsequent daily illicit opioid use among people who use drugs (PWUD).

METHODS

Data (2006-2018) were drawn from three harmonized prospective cohorts of community-recruited PWUD in Vancouver, Canada. We used multivariable generalized linear mixed-effects modeling (GLMM) to estimate the independent association between psychedelic use and subsequent daily illicit opioid use.

RESULTS

Among 3813 PWUD at baseline, 1093 (29%) reported daily use of illicit opioids and 229 (6%) reported psychedelic use in the past six months. Over study follow-up after adjusting for a range of potential confounders, psychedelic use remained independently associated with a significantly reduced odds of subsequent daily opioid use (Adjusted Odds Ratio: 0.45; 95% Confidence Interval: 0.29 to 0.70).

CONCLUSION

While confirmation in other settings is required, these findings align with growing evidence that psychedelic use may be associated with detectable reductions in subsequent substance use including illicit opioid use.

The use of diverted pharmaceutical opioids is associated with reduced risk of fentanyl exposure among people using unregulated drugs in Vancouver, Canada

BACKGROUND

Although non-medical use of pharmaceutical opioids (POs) is associated with a number of risks, in the context of the opioid-overdose crisis, it may have the secondary benefit of decreasing the risk of exposure to more potent opioids from unregulated sources. The aim of this study was to assess the effects of using diverted POs on fentanyl exposure.

METHODS

Using data from two prospective community-recruited cohorts of people who use drugs (PWUD) in Vancouver, Canada, we estimated the independent relationship between using diverted POs and fentanyl exposure (assessed through urine drug test [UDT]) between 2016 and 2018. We also explored if participant characteristics modified this relationship.

RESULTS

Over the study period, among 1150 participants, 241 (21.0%) reported using diverted POs in 292 (12.8%) occasions. In adjusted analyses, PWUD using diverted POs had decreased odds of fentanyl exposure (Adjusted odds ratio [AOR] = 0.70, 95% CI: 0.52-0.94). The reduced odds of fentanyl exposure persisted among participants with morphine positive UDT (AOR = 0.57, 95% CI: 0.40-0.82), but not among those with negative morphine UDT (AOR = 0.91, 95% CI: 0.54-1.55).

CONCLUSION

PWUD using diverted POs in our sample were 30% less likely to be exposed to fentanyl. This reduced likelihood was primarily observed among PWUD with morphine positive UDT, which could partially be explained by longer duration of action and lower street cost of slow-release oral morphine relative to other POs and fentanyl. Findings suggest that access to a regulated supply of pharmaceutical-grade opioids may serve to reduce fentanyl-related harms.

The impact of relaxation of methadone take-home protocols on treatment outcomes in the COVID-19 era

BACKGROUND

Background: In response to the COVID-19 pandemic, the US Substance Abuse and Mental Health Services Administration (SAMHSA) allowed for an increase in methadone take-home doses for the treatment of Opioid Use Disorder (OUD) in March 2020.

OBJECTIVE

To evaluate the effects of the SAMSHA exemption on methadone adherence and OUD-related outcomes.

METHODS

A convenience sample of 183 clients (58% female) were recruited from a methadone clinic in the fall of 2019 for a cross-sectional survey. Survey data was linked to clinical records, including urine drug testing (UDT) results for methadone and emergency department (ED) visits at the local hospital. Participants were on stable methadone dosing for 9 months prior to and following March 2020. Methadone adherence was assessed by UDTs; OUD-related outcomes were assessed by overdose events and ED visits. Logistic regression was used to assess the association between change in take-home methadone doses and outcomes.

RESULTS

Mean take-home doses increased nearly 200% (11.4 doses/30 days pre-COVID-19 vs. 22.3 post-SAMHSA exemption). ED visits dropped from 74 (40.4%) pre-COVID-19 to 56 (30.6%) post-SAMHSA exemption (p = <0.001). No significant changes were observed in either the number of clients experiencing overdose or those who experienced one or more methadone negative UDTs in the post-SAMHSA exemption period. Adjusted models did not show a significant association between changes in take-home doses and associated outcomes.

CONCLUSIONS

Despite a near-doubling of take-home methadone doses during the COVID-19 exemption period, the increase in take-home doses was not associated with negative treatment outcomes in methadone-adherent clients.

Methadone and buprenorphine discontinuation among postpartum women with opioid use disorder

BACKGROUND

The postpartum year is a vulnerable period for women with opioid use disorder, with increased rates of fatal and nonfatal overdose; however, data on the continuation of medications for opioid use disorder on a population level are limited.

OBJECTIVE

This study aimed to examine the effect of discontinuing methadone and buprenorphine in women with opioid use disorder in the year following delivery and determine the extent to which maternal and infant characteristics are associated with time to discontinuation of medications for opioid use disorder.

STUDY DESIGN

This population-based retrospective cohort study used linked administrative data of 211,096 deliveries in Massachusetts between 2011 and 2014 to examine the adherence to medications for opioid use disorder. Individuals receiving medications for opioid use disorder after delivery were included in the study. Here, demographic, psychosocial, prenatal, and delivery characteristics are described. Kaplan-Meier survival analysis and Cox regression modeling were used to examine factors associated with medication discontinuation.

RESULTS

A total of 2314 women who received medications for opioid use disorder at delivery were included in our study. Overall, 1484 women (64.1%) continued receiving medications for opioid use disorder for a full 12 months following delivery. The rate of continued medication use varied from 34% if women started on medications for opioid use disorder the month before delivery to 80% if the medications were used throughout pregnancy. Kaplan-Meier survival curves differed by maternal race and ethnicity (the 12-month continuation probability was .65 for White non-Hispanic women and .51 for non-White women; P<.001) and duration of use of prenatal medications for opioid use disorder (12-month continuation probability was .78 for women with full prenatal engagement and .60 and .44 for those receiving medications for opioid use disorder ≥5 months [but not throughout pregnancy] and ≤4 months prenatally, respectively; P<.001). In all multivariable models, duration of receipt of prenatal medications for opioid use disorder (≤4 months vs throughout pregnancy: adjusted hazard ratio, 3.26; 95% confidence interval, 2.72-3.91) and incarceration (incarceration during pregnancy or after delivery vs none: adjusted hazard ratio, 1.79; 95% confidence interval, 1.52-2.12) were most strongly associated with the discontinuation of medications for opioid use disorder.

CONCLUSION

Almost two-thirds of women with opioid use disorder continued using medications for opioid use disorder for a full year after delivery; however, the rates of medication continuation varied significantly by race and ethnicity, degree of use of prenatal medications for opioid use disorder, and incarceration status. Prioritizing medication continuation across the perinatal continuum, enhancing sex-specific and family-friendly recovery supports, and expanding access to medications for opioid use disorder despite being incarcerated can help improve postpartum medication adherence.

Characterizing the Clinical use of a Novel Video-assisted Dosing Protocol With Secure Medication Dispensers to Reduce Barriers to Opioid Treatment

OBJECTIVES

Distance and travel costs to opioid treatment programs (OTPs), especially in rural communities, are barriers to treatment for opioid use disorder. Retention rates at 12 months in our OTP are 55% (range 53%-61%). We piloted a novel treatment platform utilizing a video directly observed therapy (VDOT) smartphone app and a secure medication dispenser to support adherence with take-home doses of methadone or buprenorphine while enabling patients to maintain prosocial activities, reduce time and cost of travel, and increase retention.

METHODS

Participants (n = 58) were adults in a Vermont OTP. Inclusion criteria included travel hardship, access to Wi-Fi or cellular network, and having an iPhone 4S or Android 4.0 or greater. Patients received a dispenser, VDOT app, clinic dispensed medication, counseling, and urine drug testing. Chart reviews assessed VDOT compliance, engagement in prosocial activities, travel costs and time savings, and treatment disposition/retention. Project-associated costs were examined.

RESULTS

Of the 15,831 expected videos, 15,581 (98.4%) were received and only 10 (0.063%) showed signs of medication noncompliance with 1 (0.0064%) showing an overt attempt at diversion. About 93% of participants engaged in prosocial activities, travel time and costs were reduced 86%, median cost saved $72 weekly, median travel time saved 5.5 hours weekly and 98% of participants were in treatment 12 months later.

CONCLUSIONS

VDOT participants using dispensers showed high levels of medication ingestion integrity, had favorable clinical stability, and lower travel time and costs. These findings suggest that using VDOT with dispensers may hold promise as an innovative platform for supporting medication adherence.

High-Dose Buprenorphine Induction in the Emergency Department for Treatment of Opioid Use Disorder

Importance

Emergency departments (EDs) sporadically use a high-dose buprenorphine induction strategy for the treatment of opioid use disorder (OUD) in response to the increasing potency of the illicit opioid drug supply and commonly encountered delays in access to follow-up care.

Objective

To examine the safety and tolerability of high-dose (>12 mg) buprenorphine induction for patients with OUD presenting to an ED.

Design, Setting, and Participants

In this case series of ED encounters, data were manually abstracted from electronic health records for all ED patients with OUD treated with buprenorphine at a single, urban, safety-net hospital in Oakland, California, for the calendar year 2018. Data analysis was performed from April 2020 to March 2021.

Interventions

ED physicians and advanced practice practitioners were trained on a high-dose sublingual buprenorphine induction protocol, which was then clinically implemented.

Main Outcomes and Measures

Vital signs; use of supplemental oxygen; the presence of precipitated withdrawal, sedation, and respiratory depression; adverse events; length of stay; and hospitalization during and 24 hours after the ED visit were reported according to total sublingual buprenorphine dose (range, 2 to >28 mg).

Results

Among a total of 391 unique patients (median [interquartile range] age, 36 [29-48] years), representing 579 encounters, 267 (68.3%) were male and 170 were (43.5%) Black. Homelessness (88 patients [22.5%]) and psychiatric disorders (161 patients [41.2%]) were common. A high dose of sublingual buprenorphine (>12 mg) was administered by 54 unique clinicians during 366 (63.2%) encounters, including 138 doses (23.8%) greater than or equal to 28 mg. No cases of respiratory depression or sedation were reported. All 5 (0.8%) cases of precipitated withdrawal had no association with dose; 4 cases occurred after doses of 8 mg of buprenorphine. Three serious adverse events unrelated to buprenorphine were identified. Nausea or vomiting was rare (2%-6% of cases). The median (interquartile range) length of stay was 2.4 (1.6-3.75) hours.

Conclusions and Relevance

These findings suggest that high-dose buprenorphine induction, adopted by multiple clinicians in a single-site urban ED, was safe and well tolerated in patients with untreated OUD. Further prospective investigations conducted in multiple sites would enhance these findings.

Trajectories of Retention in Opioid Agonist Therapy and Overdose Risk During a Community-Wide Overdose Epidemic in a Canadian Setting

INTRODUCTION

Retention in opioid agonist therapy consistently has been linked with improved outcomes among people with opioid use disorder. However, less is known about the links between patterns of engagement in opioid agonist therapy over the long term and overdose risk. This study assesses the association of opioid agonist therapy retention trajectories with nonfatal overdose.

METHODS

Data were drawn from 2 community-recruited prospective cohorts of people who use drugs in Vancouver, Canada. Latent class growth analysis was used to identify trajectories of opioid agonist therapy retention among people with opioid use disorder initiating therapy, and generalized estimating equations assessed the association of these trajectories with nonfatal overdose events after opioid agonist therapy initiation.

RESULTS

Between 2005 and 2018, among 438 opioid agonist therapy initiators, 4 retention trajectories were identified: consistently high (35.6%), increasing (26.0%), consistently low (23.3%), and decreasing (15.1%) opioid agonist therapy engagement. During the study period, there were 371 nonfatal overdose events, with 179 (40.1%) participants reporting ≥1. In adjusted analysis, the consistently low (AOR=1.73, 95% CI=1.10, 2.71) and decreasing (AOR=1.87, 95% CI=1.18, 2.95) retention trajectories were positively associated with increased odds of nonfatal overdose compared with the consistently high opioid agonist therapy retention class.

CONCLUSIONS

Suboptimal trajectories of opioid agonist therapy retention were associated with an increased likelihood of nonfatal overdose. These findings suggest that reducing the barriers to sustained engagement in opioid agonist therapy will be critical to address North America's overdose epidemic.

Long term pre-treatment opioid use trajectories in relation to opioid agonist therapy outcomes among people who use drugs in a Canadian setting

BACKGROUND

Opioid agonist therapy (OAT) models are generally provided without consideration of how pre-treatment characteristics may be associated with outcome. Therefore, we aimed to first characterize longitudinal trajectories of opioid use before initiating OAT. Then we explored the impact of OAT on opioid use across these pre-treatment trajectories.

METHODS

Data were derived from three prospective cohort studies involving people who use drugs in Vancouver, Canada. Latent class growth analysis was applied to identify opioid use trajectories based on individual-level observations three years before starting OAT. Multivariable generalized linear mixed model was used to examine whether engaging in OAT was associated with lower risk of illicit opioid use among participants with different pre-treatment opioid use trajectories.

RESULTS

464 participants were included in the study between September 2005 and November 2018. Two pre-treatment opioid use trajectories were identified: high frequency users (246, 53.0%) and gradually increasing frequency users (218, 47.0%). We observed different strengths of association between OAT engagement and illicit opioid use among high frequency users (adjusted odds ratio [AOR] = 0.36, 95% Confidence Interval [CI]: 0.20 - 0.63) and gradually increasing frequency users (AOR = 0.91, 95% CI: 0.53 - 1.56). Unstable housing, any stimulant use, experiencing violence, drug dealing, sex work involvement, and incarceration were independently and positively associated with ongoing illicit opioid use.

CONCLUSIONS

Distinct pre-treatment opioid use trajectories are likely to influence treatment outcomes. Research is required to determine if tailored strategies specific to people with different pre-treatment opioid use patterns have potential to improve outcomes of OAT.

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.