Changes in substance use in relation to opioid agonist therapy among people who use drugs in a Canadian setting.
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ABSTRACT: Background
Although previous studies have shown that opioid agonist therapy (OAT) is linked to reductions in illicit opioid use, less is known about how OAT impacts the use of other psychoactive substances. We aimed to examine the changes in use of different substances by comparing patterns before and after initiating OAT.Methods
Data for this study was derived from three ongoing prospective cohorts involving people who use drugs in Vancouver, Canada from 1996 to 2018. We assessed use patterns for heroin, illicit prescription opioid, cocaine, crack cocaine, crystal methamphetamine, cannabis, daily alcohol use, and benzodiazepines. Segmented regression was conducted to compare the trends of substance use between pre-treatment and post-treatment periods.Results
The study included 1107 participants. After OAT engagement, we observed an immediate decline in the proportion as well as a decreasing trend for heroin (Adjusted Odds Ratio (AOR): 0.80, 95% confidence interval (CI): 0.77, 0.83), illicit prescription opioid (AOR: 0.87, 95% CI: 0.83, 0.90), and benzodiazepines (AOR: 0.73, 95 % CI: 0.67, 0.80). There was no significant difference comparing the pre-treatment and post-treatment trends for cocaine, crack cocaine, crystal methamphetamine, and cannabis. However, higher growth slope was noted during the post-treatment period for daily alcohol use (P = 0.016).Conclusions
We observed significant reduction in illicit opioids use following OAT initiation, but not for stimulant and cannabis. The increasing problematic use of alcohol may pose challenges to the safety and effectiveness of OAT. Development of comprehensive and tailored treatment strategies is needed for poly-substance users accessing OAT.
SUBMITTER: Dong H
PROVIDER: S-EPMC7462099 | biostudies-literature |
REPOSITORIES: biostudies-literature
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Project description:Background and Aims: Little is known about how the expansion of opioid agonist therapy (OAT) and emergence of fentanyl in the illicit drug supply in North America has influenced non-fatal opioid overdose (NFOD) risk. Therefore, we sought to identify patterns of substance use and addiction treatment engagement (i.e., OAT, other inpatient or outpatient treatment) prior to NFOD, as well as the trends and correlates of each pattern among people who use drugs (PWUD) in Vancouver, Canada. Methods: Data were derived from participants in three prospective cohorts of PWUD in Vancouver in 2009-2016. Observations from participants reporting opioid-related NFOD in the previous six months were included. A latent class analysis was used to identify classes based on substances used at the time of last NFOD and addiction treatment engagement in the month prior to the last NFOD. Multivariable generalized estimating equations estimated the correlates of each class membership. Results: In total, 889 observations from 570 participants were included. Four distinct classes were identified: (1) polysubstance use (PSU) and addiction treatment engagement; (2) PSU without treatment engagement; (3) exposure to unknown substances, mostly without treatment engagement; and (4) primary heroin users without treatment engagement. The class of exposure to unknown substances appeared in 2015 and became the dominant group (76.9%) in 2016. In multivariable analyses, the odds of membership in the class of primary heroin users decreased over time (adjusted odds ratio [AOR]: 0.74, 95% confidence interval [CI]: 0.68-0.81). Conclusions: Changing profiles of PWUD reporting opioid-related NFOD were seen over time. Notably, there was a sudden increase in reports of overdose following exposure to unknown substances since 2015, the majority of whom reported no recent addiction treatment engagement. Further study into patterns of substance use and strategies to improve addiction treatment engagement is needed to improve and focus overdose prevention efforts.
| S-EPMC7377957 | biostudies-literature
Project description:BackgroundOpioid agonist treatment (OAT) reduces many of the harms associated with opioid dependence. We use mathematical modelling to comprehensively evaluate the overall health benefits of OAT in people who inject drugs in Perry County (KY, USA), Kyiv (Ukraine), and Tehran (Iran).MethodsWe developed a dynamic model of HIV and hepatitis C virus (HCV) transmission, incarceration, and mortality through overdose, injury, suicide, disease-related and other causes. The model was calibrated to site-specific data using Bayesian methods. We evaluated preventable drug-related deaths (deaths due to HIV, HCV, overdose, suicide, or injury) averted over 2020-40 for four scenarios, added incrementally, compared with a scenario without OAT: existing OAT coverage (setting-dependent; community 4-11%; prison 0-40%); scaling up community OAT to 40% coverage; increasing average OAT duration from 4-14 months to 2 years; and scaling up prison-based OAT.OutcomesDrug-related harms contributed differentially to mortality across settings: overdose contributed 27-47% (range of median projections) of preventable drug-related deaths over 2020-40, suicide 6-17%, injury 3-17%, HIV 0-59%, and HCV 2-18%. Existing OAT coverage in Tehran (31%) could have a substantial effect, averting 13% of preventable drug-related deaths, but will have negligible effect (averting <2% of preventable drug-related deaths) in Kyiv and Perry County due to low OAT coverage (<4%). Scaling up community OAT to 40% could avert 12-24% of preventable drug-related deaths, including 13-22% of overdose deaths, with greater effect in settings with significant HIV mortality (Tehran and Kyiv). Improving OAT retention and providing prison-based OAT would have a significant additional effect, averting 27-51% of preventable drug-related deaths.InterpretationOAT can substantially reduce drug-related harms, particularly in settings with HIV epidemics in people who inject drugs. Maximising these effects requires research and investment into achieving higher coverage and provision and longer retention of OAT in prisons and the community.FundingUK National Institute for Health Research, US National Institute on Drug Abuse.
| S-EPMC8255389 | biostudies-literature
Project description:ImportanceDrug use and incarceration have a substantial impact on rural communities, but factors associated with the incarceration of rural people who use drugs (PWUD) have not been thoroughly investigated.ObjectiveTo characterize associations between recent incarceration, overdose, and substance use disorder (SUD) treatment access among rural PWUD.Design, setting, and participantsFor this cross-sectional study, the Rural Opioid Initiative research consortium conducted a survey in geographically diverse rural counties with high rates of overdose across 10 US states (Illinois, Wisconsin, North Carolina, Oregon, Kentucky, West Virginia, Ohio, Massachusetts, New Hampshire, and Vermont) between January 25, 2018, and March 17, 2020, asking PWUD about their substance use, substance use treatment, and interactions with the criminal legal system. Participants were recruited through respondent-driven sampling in 8 rural US regions. Respondents who were willing to recruit additional respondents from their personal networks were enrolled at syringe service programs, community support organizations, and through direct community outreach; these so-called seed respondents then recruited others. Of 3044 respondents, 2935 included participants who resided in rural communities and reported past-30-day injection of any drug or use of opioids nonmedically via any route. Data were analyzed from February 8, 2022, to September 15, 2023.ExposureRecent incarceration was the exposure of interest, defined as a report of incarceration in jail or prison for at least 1 day in the past 6 months.Main outcomes and measuresThe associations between PWUD who were recently incarcerated and main outcomes of treatment use and overdose were examined using logistic regression.ResultsOf 2935 participants, 1662 (56.6%) were male, 2496 (85.0%) were White; the mean (SD) age was 36 (10) years; and in the past 30 days, 2507 (85.4%) reported opioid use and 1663 (56.7%) reported injecting drugs daily. A total of 1224 participants (41.7%) reported recent incarceration, with a median (IQR) incarceration of 15 (3-60) days in the past 6 months. Recent incarceration was associated with past-6-month overdose (adjusted odds ratio [AOR], 1.38; 95% CI, 1.12-1.70) and recent SUD treatment (AOR, 1.62; 95% CI, 1.36-1.93) but not recent medication for opioid use disorder (MOUD; AOR, 1.03; 95% CI, 0.82-1.28) or currently carrying naloxone (AOR, 1.02; 95% CI, 0.86-1.21).Conclusions and relevanceIn this cross-sectional study of PWUD in rural areas, participants commonly experienced recent incarceration, which was not associated with MOUD, an effective and lifesaving treatment. The criminal legal system should implement effective SUD treatment in rural areas, including MOUD and provision of naloxone, to fully align with evidence-based SUD health care policies.
| S-EPMC10636631 | biostudies-literature
Project description:BackgroundMethamphetamine use is common among persons with opioid use disorder. This study evaluated associations between methamphetamine use and treatment with agonist medications for opioid use disorder (MOUD, specifically buprenorphine, and/or methadone) in U.S. rural communities.MethodsThe Rural Opioid Initiative (ROI) is a consortium spanning 10 states and 65 rural counties that included persons who reported past 30-day use of opioids and/or injection drug use between 1/2018 and 3/2020. Analyses were restricted to participants who had ever used opioids and had data on past 30-day methamphetamine use. Multivariable models examined the relationship between methamphetamine use and utilization of agonist MOUD.ResultsAmong 2899 participants, 2179 (75.2%) also reported recent methamphetamine use. Persons with methamphetamine use compared to those without were younger, more likely to have injected drugs, be unhoused, criminal justice involved, and less likely to have health insurance. Adjusted for age, sex, race, and study site, recent methamphetamine use was associated with lower relative odds of past 30-day methadone treatment (aOR=0.66; 95% CI: 0.45-0.99) and fewer methadone treatment days (aIRR=0.76; 0.57-0.99), but not past 30-day buprenorphine receipt (aOR=0.90; 0.67-1.20), buprenorphine treatment days in past 6 months: aIRR=0.88; 0.69-1.12) or perceived inability to access buprenorphine (aOR=1.12; 0.87-1.44) or methadone (aOR=1.06; 0.76-1.48).ConclusionMethamphetamine use is common among persons who use opioids in rural U.S. areas and negatively associated with current treatment and retention on methadone but not buprenorphine. Future studies should examine reasons for this disparity and reduce barriers to methadone for persons who use opioids and methamphetamine.
| S-EPMC10599300 | biostudies-literature
Project description:Background and aimGlobally, nearly one in five people who inject drugs (PWID) are living with HIV, and the rate of new HIV infections in PWID is increasing in some settings. Early diagnosis is crucial for effective HIV control. We reviewed the evidence on the association between opioid agonist therapy (OAT) and HIV testing uptake among PWID.MethodsWe conducted a systematic review searching MEDLINE, Scopus, Web of Science, Cochrane Central Register of Controlled Trials and PsycINFO for studies published from January 2000 to March 2019. Reference lists and conference proceedings were hand-searched. Observational and intervention studies were eligible for inclusion. Risk of bias was assessed using the Risk of Bias in Non-Randomised Studies of Interventions (ROBINS-I) tool. Meta-analyses were conducted using random-effects models.ResultsOf 13 373 records identified, 11 studies from Australia, Europe, Malaysia and the United States were included. All studies had at least a serious risk of bias, largely due to confounding and selection bias, making it difficult to draw causal conclusions from the evidence. Ten studies provided data on the association between current OAT use and recent HIV testing. Six showed a positive association, while four provided little evidence of an association: pooled odds ratio (OR) = 1.71, 95% confidence interval (CI) = 1.28-2.27. Looking at having ever been on OAT and having ever been HIV tested, seven studies showed a positive association and three showed either weak or no evidence of an association: pooled OR = 3.82, 95% CI = 2.96-4.95.ConclusionsOpioid agonist therapy may increase uptake of HIV testing among people who inject drugs, providing further evidence that opioid agonist therapy improves the HIV treatment care cascade.
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Project description:IntroductionRetention 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.MethodsData 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.ResultsBetween 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.ConclusionsSuboptimal 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.
| S-EPMC7978040 | biostudies-literature
Project description:HIV-infected drug users have increased age-matched morbidity and mortality compared with HIV-infected people who do not use drugs. Substance-use disorders negatively affect the health of HIV-infected drug users, who also have frequent medical and psychiatric comorbidities that complicate HIV treatment and prevention. Evidence-based treatments are available for the management of substance-use disorders, mental illness, HIV and other infectious complications such as viral hepatitis and tuberculosis, and many non-HIV-associated comorbidities. Tuberculosis co-infection in HIV-infected drug users, including disease caused by drug-resistant strains, is acquired and transmitted as a consequence of inadequate prescription of antiretroviral therapy, poor adherence, and repeated interfaces with congregate settings such as prisons. Medication-assisted therapies provide the strongest evidence for HIV treatment and prevention efforts, yet are often not available where they are needed most. Antiretroviral therapy, when prescribed and adherence is at an optimum, improves health-related outcomes for HIV infection and many of its comorbidities, including tuberculosis, viral hepatitis, and renal and cardiovascular disease. Simultaneous clinical management of multiple comorbidities in HIV-infected drug users might result in complex pharmacokinetic drug interactions that must be adequately addressed. Moreover, interventions to improve adherence to treatment, including integration of health services delivery, are needed. Multifaceted, interdisciplinary approaches are urgently needed to achieve parity in health outcomes in HIV-infected drug users.
| S-EPMC4855280 | biostudies-literature
Project description:BackgroundPeople with substance use disorders generally have unhealthy diets, including limited intake of fruit and vegetables. Evidence shows substantial health benefits from increasing fruit and vegetable consumption on various indicators and possibly also psychological distress. A pilot study has indicated that supplementation with fruit smoothie could be promising also among people receiving opioid agonist therapy for opioid dependence. FruktBAR will compare the efficacy of added fruit smoothie supplementation to people receiving opioid agonist therapy compared to standard treatment without added supplementation.MethodsFruktBAR is a multicentre, randomised controlled trial. The trial will aim to recruit 302 patients receiving opioid agonist therapy. The intervention involves daily supplementation with 250 ml fruit smoothie including a variety of fruits such as apple, pineapple, mango, bananas, orange, blueberries, passion fruit, coconut, lime, and blackcurrant. The main endpoints are 16 weeks after intervention initiation. Participants will be included and followed up during and after the intervention. The target group will be patients with opioid dependence receiving opioid agonist therapy from involved outpatient clinics in Bergen and Stavanger, two of the largest cities in Norway. The main outcome is psychological distress assessed with Hopkins Symptom Checklist (SCL-10) at the end of the intervention period 16 weeks after initiation, and will be compared between the intervention and control arms. Secondary outcome measures are changes in fatigue, physical functioning assessed with a 4-minute step-test, health-related quality of life, biochemical indicators of inflammation, and biochemical indicators of fruit intake.DiscussionThis study will inform on the relative advantages or disadvantages of fruit supplementation in addition to the current medically and psychologically oriented treatment of people receiving opioid agonist therapy. If the supplementation is efficacious, it can be considered for further scale-up.Trial registrationRegistered 2022-02-08 in ClinicalTrials.gov , identifier NCT05229770.
| S-EPMC9441043 | biostudies-literature
Project description:Rates of sexually transmitted infections (STI) and unplanned pregnancy are high among youth. While the intersection between drug and alcohol use and unprotected sex is well recognized, few studies have examined the relationship between substance use patterns and unprotected sex among high risk-populations such as street-involved youth.Data were derived from the At-Risk Youth Study (ARYS), a prospective cohort of street-involved youth from Vancouver, Canada. Generalized estimating equations (GEE) were used to examine substance use patterns that were independently associated with unprotected sex, defined as (vaginal or anal) sexual intercourse without consistent condom use.Between September 2005 and May 2013, 1,026 youth were recruited into the ARYS cohort and 75% (n = 766) reported engaging in recent unprotected sex at some point during the study period. In a multivariable analysis, female gender (adjusted odds ratio [AOR] = 1.46, 95% confidence interval [CI]: 1.18-1.81), Caucasian ancestry (AOR = 1.38, 95% CI: 1.13-1.68), being in a stable relationship (AOR = 4.64, 95% CI: 3.82-5.65), having multiple sex partners (AOR = 2.60, 95% CI: 2.18-3.10) and the following substance use patterns were all independently associated with recent unprotected sex: injection or non-injection crystal methamphetamine use (AOR = 1.21, 95% CI: 1.03-1.43), injection or non-injection cocaine use (AOR = 1.20, 95% CI: 1.02-1.41), marijuana use (AOR = 1.23, 95% CI: 1.02-1.49), ecstasy use (AOR = 1.23, 95% CI: 1.01-1.48) and alcohol use (AOR = 1.31, 95% CI: 1.11-1.55) (all p < 0.05).Unprotected sex was prevalent among street-involved youth in this setting, and independently associated with female gender and a wide range of substance use patterns. Evidence-based and gender-informed sexual health interventions are needed in addition to increased access to youth-centered addiction treatment services. STI testing and linkages to healthcare professionals remain important priorities for street-involved youth, and should be integrated across all health and social services.
| S-EPMC4700772 | biostudies-other
Project description:BackgroundPeople who inject drugs (PWID) are at high risk of hepatitis C virus (HCV) infection. Trends in HCV incidence and associated risk factors among PWID recruited between 1996 and 2012 in Vancouver, Canada were evaluated.MethodsData were derived from a long-term cohort of PWID in Vancouver. Trends in HCV incidence were evaluated. Factors associated with time to HCV infection were assessed using Cox proportional hazards regression.ResultsAmong 2,589, 82% (n = 2,121) were HCV antibody-positive at enrollment. Among 364 HCV antibody-negative participants with recent (last 30 days) injecting at enrollment, 126 HCV seroconversions were observed [Overall HCV incidence density: 8.6 cases/100 person-years (py); 95% confidence interval (95% CI): 7.2, 10.1; HCV incidence density among those with injecting during follow-up: 11.5 cases/100 py; 95% CI 9.7, 13.6]. The overall HCV incidence density declined significantly from 25.0/100 py (95% CI: 20.2, 30.3) in 1996-99, as compared to 6.0/100 py (95% CI: 4.1, 8.5) in 2000-2005, and 3.1/100 py (95% CI: 2.0, 4.8) in 2006-2012. Among those with injecting during follow-up, the overall HCV incidence density declined significantly from 27.9/100 py (95% CI: 22.6, 33.6) in 1996-99, as compared to 7.5/100 py (95% CI: 5.1, 10.6) in 2000-2005, and 4.9/100 py (95% CI: 3.1, 7.4) in 2006-2012. Unstable housing, HIV infection, and injecting of cocaine, heroin and methamphetamine were independently associated with HCV seroconversion.ConclusionsHCV incidence has dramatically declined among PWID in this setting. However, improved public health strategies to prevent and treat HCV are urgently required to reduce HCV-associated morbidity and mortality.
| S-EPMC4045728 | biostudies-literature