Impact of cannabis use during stabilization on methadone maintenance treatment

Perspectives regarding cannabis use: Results from a qualitative study of individuals engaged in substance use treatment in Georgia and Connecticut

Objective

Cannabis use is increasingly pervasive throughout the U.S. People in treatment for substance use disorders (SUD) may be especially at-risk of harm due to this changing context of cannabis in the U.S. This study's objective was to qualitatively describe experiences and beliefs around cannabis among people who had entered treatment for any SUD in the past 12-months.

Methods

From May to November of 2022, we conducted 27 semi-structured interviews (n=16 in Georgia, n=11 in Connecticut) with individuals in treatment for SUD in Georgia and Connecticut. Interviews were recorded, transcribed, and thematically analyzed using an emergent approach.

Results

All participants had used cannabis in the past. Four themes emerged from the interviews. Participants: (1) perceived cannabis as an important contributor to non-cannabis substance use initiation in adolescence; (2) viewed cannabis as a substance with the potential to improve health with fewer side effects than prescription medications; (3) expressed conflicting opinions regarding cannabis as a trigger or tool to manage cravings for other non-cannabis substances currently; and 4) described concerns related to negative legal, social service, and treatment-related consequences as well as negative peer perception relating to the use of cannabis.

Conclusion

Although participants described cannabis's important role as an initiatory drug in adolescence and young adulthood, many felt that cannabis was a medicinal substance for a range of health challenges. These findings suggest SUD treatment clinicians should address medicinal beliefs related to cannabis among their clients and emphasizes the need for research on cannabis use and SUD treatment outcomes.

Cannabis donation as a harm reduction strategy: a case study

BACKGROUND

The United States (US) continues to experience unprecedented rates of overdose mortality and there is increased need to identify effective harm reduction practices. Research from Canada describes cannabis donation through harm reduction agencies as an adjunctive strategy to mitigate the negative consequences of more harmful drugs. This case study describes the operational logistics, feasibility, and potential benefits of a cannabis donation program that was operated through a harm reduction program in rural Michigan.

CASE PRESENTATION

We applied a community driven research approach to gather information from harm reduction program staff about the implementation and evolution of cannabis donation efforts in Michigan. We also examined 20-months (September 2021 through May 2023) of administrative data from a cannabis company to compare the sale and donation of cannabis products. Ten cannabis-experienced harm reduction clients received cannabis donations, with clinical staff determining client interest and appropriateness, and providing weekly pick-up or delivery. To expand product availability and sustainability, we examined administrative data from a commercialcannabis company that volunteered to provide donations. This administrative data suggests that while flower products constitute most of the adult and medical sales, edible, oil, and topical products predominated donations. Further, cost analysis suggests that donations represent only 1% of total gross sales and account for much less than the expected yearly donation amount.

CONCLUSIONS

Research suggests there is potential to reduce alcohol and drug use related harms of more dangerous substances through substitution with cannabis. This case study is the first to document cannabis donation as a harm reduction practice in the US and suggests potential for sustainability dependent on state laws. Findings from this case study provide a starting point for inquiry into cannabis donation as a harm reduction strategy in the US; future research is needed to fully understand the individual-level outcomes, public health impacts, necessary legal regulations, and best practices for cannabis donation programs through harm reduction organizations.

Neurocognitive Dysfunctions in People with Concurrent Cannabis Use and Opioid Dependence: A Cross-Sectional, Controlled Study

Cannabis and opioid co-dependence is independently associated with cognitive impairments. We examined neurocognitive dysfunctions in people with concurrent opioid dependence with cannabis dependence (OD+CD) or cannabis use (OD+CU) compared to those with only opioid dependence (OD) and healthy controls (HC). We selected adult participants, any sex, who met the diagnosis of OD (N = 268), OD+CU (N = 58), and OD + CD (N = 115). We recruited 68 education-matched HC. We administeredStandard progressive matrices (SPM), Wisconsin card sorting test (WCST), Iowa gambling task (IGT), Trail making tests A and B (TMT), and verbal and visual working memory 1-, 2-backtests. 496 (97.5%) were men, and 13 (2.5%) were women. In WCST, OD and OD+CD had significantly higher non-perseverative errors than HC. OD+CD group completed significantly lesser categories than HC. In verbal working memory 2-back, HC scored significantly fewer errors than OD and OD +CD. All patient groups, OD, OD+CU, and OD+CD, scored higher commission errors than HC in visual working memory 1-back. OD and OD+CD scored higher commission and total errors than the controls. OD+CU showed lesser error score than HC in TMT B. Cannabis and opioid co-dependence contribute to cognitive impairments, especially in working memory and executive functions.

The impact of cannabis on non-medical opioid use among individuals receiving pharmacotherapies for opioid use disorder: a systematic review and meta-analysis of longitudinal studies

Background: The relationship between cannabis use and the risk of returning to using opioids non-medically during treatment for opioid use disorder (OUD) remains unclear.Objective: We sought to quantify the impact of cannabis use on the risk of non-medical opioid use among people receiving pharmacotherapies for OUD.Methods: A comprehensive search was performed using multiple databases from March 1 to April 5 of 2023. Eligible studies longitudinally assessed the association between cannabis use and non-medical opioid use among people with OUD receiving treatment with buprenorphine, methadone, or naltrexone. We utilized a random-effects model employing the restricted maximum likelihood method. A sensitivity analysis was conducted to understand potential differences between each OUD treatment modality.Results: A total of 10 studies were included in the final meta-analysis. There were 8,367 participants (38% female). The average follow-up time across these studies was 9.7 months (SD = 3.77), ranging from 4 to 15 months. The pharmacotherapies involved were methadone (76.3%) buprenorphine (21.3%), and naltrexone (2.4%). The pooled odds ratio did not indicate that cannabis use significantly influenced non-medical opioid use (OR: 1.00, 95% CI: 0.97-1.04, p = .98). There is evidence of moderate heterogeneity and publication bias.Conclusion: There was no significant association between cannabis use and non-medical opioid use among patients receiving pharmacotherapies for OUD. These findings neither confirm concerns about cannabis increasing non-medical opioid use during MOUD, nor do they endorse its efficacy in decreasing non-medical opioid use with MOUD. This indicates a need for individualized approaches for cannabis use and challenges the requirement of cannabis abstinence to maintain OUD pharmacotherapies.

Implications of Cannabis Legalization on Substance-Related Benefits and Harms for People Who Use Opioids: A Canadian Perspective

In 2018, Canada enacted the Cannabis Act, becoming only the second country (after Uruguay) to legalize the recreational consumption of cannabis. Although there is ongoing global disagreement on the risk-benefit profile of cannabis with increasing legalization in many parts of the world, the evidence of rising cannabis use prevalence postlegalization has been consistent. In contrast, postlegalization changes in various cannabis-related metrics have been inconsistent in Canada and other parts of the world. Furthermore, the implications of cannabis legalization on substance-related harms and benefits for people who use unregulated drugs, particularly opioids, remain unclear. Finally, although Canada did not legalize cannabis to address the opioid crisis, there is rising scientific and popular interest in the therapeutic potential of cannabis to mitigate opioid-related harms. This perspective highlights the implications of cannabis legalization on substance-related benefits and harms for people who use opioids, the current state of Canadian research, and suggestions for future directions.

"Breaking bud": the effect of direct chemical modifications of phytocannabinoids on their bioavailability, physiological effects, and therapeutic potential

Tetrahydrocannabinol (THC) and cannabidiol (CBD) are the two "major cannabinoids". However, their incorporation into clinical and nutraceutical preparations is challenging, owing to their limited bioavailability, low water solubility, and variable pharmacokinetic profiles. Understanding the organic chemistry of the major cannabinoids provides us with potential avenues to overcome these issues through derivatization. The resulting labile pro-drugs offer ready cannabinoid release in vivo, have augmented bioavailability, or demonstrate interesting pharmacological properties in their own right. This review identifies and discusses a subset of these advanced derivatization strategies for the major cannabinoids, where the starting material is the pure phytocannabinoid itself, and the final product either a cannabinoid pro-drug, or a novel pharmacoactive material.

The Cannabis-Dependent Relationship Between Methadone Treatment Dose and Illicit Opioid Use in a Community-Based Cohort of People Who Use Drugs

Background: Methadone maintenance treatment (MMT) is an effective treatment for opioid use disorder. However, subtherapeutic dosing may lead to continued opioid use by failing to suppress opioid withdrawal and craving. Preclinical and pilot experimental research suggests that cannabinoids may reduce opioid withdrawal and craving. We sought to test whether the association between low methadone dose and illicit opioid use differs according to concurrent cannabis use patterns. Methods: Data for this study were derived from two community-recruited cohorts of people (≥18 years old) who use illicit drugs in Vancouver, Canada. We used generalized estimating equations to estimate the adjusted association between lower daily MMT dose (<90 mg/day) and daily illicit opioid use, testing for interaction between dose and daily cannabis use. Results: Between December 2005 and December 2018, 1389 participants reported MMT enrolment and were included in the study. We observed a significant interaction (p<0.01) between daily cannabis and lower MMT dose on concurrent daily illicit opioid use: lower MMT doses increased the odds of daily illicit opioid use by 86% (adjusted odds ratio [AOR]=1.86, 95% confidence interval [CI]=1.61-2.16) during periods of no or low-frequency cannabis use and by 30% during periods of daily cannabis use (AOR=1.30, 95% CI=1.01-1.67). Discussion: This study provides preliminary observational evidence that cannabis may mitigate some of the negative effects of subtherapeutic MMT dosing, guiding future clinical investigations into the safety and efficacy of cannabis and cannabinoids as adjunct treatment for MMT.

Methadone Dose, Cannabis Use, and Treatment Retention: Findings From a Community-based Sample of People Who Use Unregulated Drugs

OBJECTIVES

Lower daily methadone dose is negatively associated with retention in methadone maintenance treatment (MMT). Cannabis use during MMT is common, with many patients reporting its use for opioid withdrawal mitigation. We sought to test whether the association between lower MMT dose and treatment retention differs by concurrent high-frequency cannabis use in a community sample of people on MMT.

METHODS

We obtained data from participants initiating MMT in 2 community-recruited prospective cohorts of people who use drugs in Vancouver, Canada. We built multivariable Cox frailty models to estimate the relationships between MMT dose (<90 mg/d vs ≥90 mg/d) and time to treatment discontinuation. We included an interaction term to test whether high-frequency (≥daily) cannabis use modified the measured effect of lower treatment dose on treatment retention.

RESULTS

Between December 2005 and December 2018, 829 participants (54.1%) initiated at least 1 MMT episode and were included in the analysis. Lower MMT dose was strongly positively associated with treatment discontinuation regardless of concurrent high-frequency cannabis use (interaction P > 0.05). Structural factors including homelessness and incarceration were significantly and positively associated with treatment discontinuation.

CONCLUSIONS

Although we previously found the magnitude and strength of the relationship between lower MMT dose and high-frequency unregulated opioid use to be tempered during high-frequency cannabis use periods, this effect measure modification does not appear to translate to time retained in treatment. Cannabis-based interventions to promote retention in MMT are unlikely to produce long-term benefit without addressing external factors that place MMT patients at increased risk of treatment discontinuation.

Alleviation of opioid withdrawal by cannabis and delta-9-tetrahydrocannabinol: A systematic review of observational and experimental human studies

BACKGROUND

While six U.S. states have already officially authorized cannabinoids to substitute opioids and treat opioid use disorder, the therapeutic benefits of cannabinoids remain unclear, especially when weighted against their adverse effects.

METHODS

We conducted a systematic review of studies examining the association between opioid withdrawal and cannabis use or delta-9-tetrahydrocannabinol (THC) administration. We searched multiple databases from inception to July 30, 2022, and assessed study quality.

RESULTS

Eleven studies were identified, with a total of 5330 participants, of whom 64 % were male. Nine observational studies examined the association between cannabis use and opioid withdrawal. Two randomized, placebo-controlled clinical trials (RCTs) investigated the withdrawal-alleviating effects of dronabinol, a synthetic form of THC. Four observational studies found an association between cannabis use and the alleviation of opioid withdrawal; one reported exacerbation of opioid withdrawal symptoms; and four reported no association. RCTs reported that THC alleviated opioid withdrawal, albeit with dose-dependent increases in measures of abuse liability, dysphoria, and tachycardia. There was high heterogeneity in measurements of opioid withdrawal and the type and dose of opioid at baseline.

CONCLUSIONS

Although there is preliminary evidence that cannabis and its main psychoactive constituent, THC, may alleviate opioid withdrawal, these effects are likely to have a narrow therapeutic window. Further, the potential of cannabinoids to alleviate opioid withdrawal is determined by complex interactions between patient characteristics and pharmacological factors. Collectively, these findings have clinical, methodological, and mechanistic implications for treating opioid withdrawal during cannabinoid use, and for efforts to alleviate opioid withdrawal using non-opioid therapeutics.

Cannabinoids—Perspectives for Individual Treatment in Selected Patients: Analysis of the Case Series

Cannabinoids can be successfully used in the treatment of many symptoms and diseases; however, most often they are not the drugs of first choice. They can be added to the primary therapy, which can improve its effectiveness, or be introduced as the basic treatment when the conventional methods have failed. Small clinical trials and case reports prove the benefits of applying medicinal cannabis in various indications; however, clinical trials in larger groups of patients are scarce and often controversial. Due to limited scientific evidence, it is essential to conduct further experimental trials. Understanding the role of endocannabinoids, as well as the composition of cannabis containing both phytocannabinoids and terpenes plays an important role in their clinical use. The clinical effects of cannabinoids depend, among other things, on the activity of the endocannabinoid system, the proportion of phytocannabinoids, such as Δ9-tetrahydrocannabinol (THC) and cannabidiol (CBD), and the dosage used. The article discusses the role of phytocannabinoids and the potential of using them in different clinical cases in patients suffering from chronic pain, opioid dependence, depression and migraine, who did not respond to the conventional therapeutic methods. In each of the presented cases, the implementation of cannabinoids altered the course of the disease and resulted in symptom relief. Every decision to introduce cannabinoids to the treatment should be made individually with careful attention paid to details. Additionally, it is worth taking care of good clinical communication and education so that the implemented therapy is safe, effective and properly perceived by the patient.

The impact of marijuana use on cocaine use outcomes among patients in methadone maintenance treatment across five trials of contingency management

OBJECTIVE

Cocaine use is prevalent among patients in methadone maintenance and a risk factor for poor treatment outcomes. Contingency management (CM) decreases cocaine use in this population, but little is known about its efficacy when marijuana use is present prior to or during treatment.

METHOD

Data from five randomized CM trials (N = 557) were used to evaluate whether: (a) marijuana frequency (none, low, or high) prior to or during treatment impacts cocaine use outcomes and (b) marijuana use differentially impacts cocaine outcomes with standard care (SC) + CM versus SC alone.

RESULTS

Relative to no marijuana use, low (β = .28, p < .01) and high marijuana use (β = .32, p < .05) during treatment were associated with roughly 1 week shorter duration of cocaine abstinence on average. Low marijuana use (β = .71, p < .05) during treatment was associated with a lower proportion of negative cocaine samples during treatment relative to no marijuana use. Treatment group by marijuana use (before or during treatment) interactions on duration and proportion of cocaine abstinence during treatment were not significant. For longer term outcomes, in SC + CM, marijuana use during treatment did not impact cocaine abstinence 6 months post-baseline. In SC, low (OR = .44, p < .05) and high (OR = .26, p < .001) marijuana use during treatment decreased odds of cocaine abstinence at 6 months post-baseline relative to no use.

CONCLUSIONS

Findings highlight the benefits of SC + CM and abstaining from marijuana use during active treatment. At 6 months postbaseline, SC + CM evidenced similar cocaine abstinence regardless of marijuana use levels during treatment, while those with low and high marijuana use showed decreased abstinence rates in SC only. (PsycInfo Database Record (c) 2022 APA, all rights reserved).

The prevalence and pattern of cannabis use among patients attending a methadone treatment clinic in Nairobi, Kenya

BACKGROUND

Cannabis use during methadone treatment may negatively impact treatment outcomes. The aim of this study was to determine the prevalence and pattern of cannabis use among patients attending a methadone treatment clinic in Nairobi, Kenya.

METHODS

This was a retrospective study of 874 patients on methadone therapy at a methadone maintenance treatment clinic in Nairobi, Kenya from December 2014 to November 2018. Data on sociodemographic characteristics and drug use patterns based on urine drug screens was collected from patient files. Data was analyzed using Statistical Package for the Social Sciences (SPSS) for windows version 23.0.

RESULTS

Point prevalence of cannabis use was 85.8% (95% CI, 83.3 - 88.0) at baseline and 62.7% (95% CI, 59.5 - 65.8) during follow-up. A pattern of polysubstance use was observed where opioids, cannabis and benzodiazepines were the most commonly used drugs. The mean age of the patients was 35.3 (SD 9.0) years with the majority being male, unemployed (76%), (51.4%) had reached primary level of education, and (48.5%) were divorced or separated. University education was associated with reduced risk for cannabis use OR = 0.1 (95% CI, 0.02-0.8, p = 0.031).

CONCLUSION

Cannabis use is prevalent among patients attending a methadone treatment clinic in Kenya, suggesting need for targeted interventions to address the problem of cannabis use during methadone treatment.

Weeding out the truth: a systematic review and meta-analysis on the transition from cannabis use to opioid use and opioid use disorders, abuse or dependence

BACKGROUND AND AIMS

The idea that cannabis is a 'gateway drug' to more harmful substances such as opioids is highly controversial, yet has substantially impacted policy, education and how we conceptualize substance use. Given a rise in access to cannabis products and opioid-related harm, the current study aimed to conduct the first systematic review and meta-analysis on the likelihood of transitioning from cannabis use to subsequent first-time opioid use, opioid use disorders (OUD), dependence or abuse.

METHODS

Following Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines, pubMed/MEDLINE, Scopus, EMBASE, PsychINFO, Cochrane Central Register of Controlled Trials and Informit Health Collection were searched for full-text articles assessing the likelihood of transitioning from cannabis to subsequent opioid use, and from opioid use to OUD, abuse or dependence given prior cannabis use. Analysis of subpopulations within studies were discussed narratively, and E-values were calculated to assess the potential influence of unmeasured confounding.

FINDINGS

Six studies provided relevant data from the United States, Australia and New Zealand between 1977 and 2017, a total sample of 102 461 participants. Random-effects analysis of the adjusted pooled effect size indicates that the likelihood of transitioning from cannabis to opioid use, relative to non-cannabis users, is odds ratio (OR) = 2.76, 95% confidence interval (CI) = 2.26-3.36, whereas the likelihood of transitioning from opioid use to OUD, abuse or dependence given prior cannabis use is OR = 2.52, 95% CI = 1.65-3.84. While the evidence was determined to be of low quality with moderate risk of bias, E-values suggest that these findings are robust against unmeasured confounding.

CONCLUSION

A systematic review and meta-analysis found that while people who use cannabis are disproportionately more likely to initiate opioid use and engage in problematic patterns of use than people who do not use cannabis, the low quality of the evidence must be considered when interpreting these findings.

Prevalence of Cannabis Use and Cannabis Route of Administration among Massachusetts Adults in Buprenorphine Treatment for Opioid Use Disorder

BACKGROUND

Recent prevalence estimates of cannabis use among individuals receiving medication treatment for OUD (MOUD) are lacking, and no study has characterized cannabis route of administration (cROA) in this population. These knowledge gaps are relevant because cannabis' effects and health outcomes vary by cROA and the availability and perceptions of cROA (e.g., vaping devices) are changing.

METHODS

The Vaping In Buprenorphine-treated patients Evaluation (VIBE) cross-sectional survey assessed the prevalence and correlates of cannabis use and cROA among adults receiving buprenorphine MOUD from 02/20 to 07/20 at five community health centers in Massachusetts, a state with legal recreational and medical cannabis use.

RESULTS

Among the 92/222 (41%) respondents reporting past 30-day cannabis use, smoking was the most common cROA (75%), followed by vaping (38%), and eating (26%). Smoking was more often used as a single cROA vs. in combination others (p = 0.01), whereas vaping, eating, and dabbing were more often used in combination with another cROA (all p < 0.05). Of the 39% of participants reporting multiple cROA, smoking and vaping (61%), and smoking and eating (50%), were the most prevalent combinations. Nonwhite race (vs. white) and current cigarette smoking (vs. no nicotine use) were associated with past 30-day cannabis use in multiple logistic regression.

CONCLUSIONS

Prevalence of past 30-day cannabis use among individuals receiving buprenorphine MOUD in Massachusetts in 2020 was nearly double the prevalence of cannabis use in Massachusetts' adult general population in 2019 (21%). Our data are consistent with state and national data showing smoking as the most common cROA.

Green Hope: Perspectives on Cannabis from People who Use Opioids

While states are implementing policies to legalize cannabis for medical or recreational purposes, it remains a Schedule 1 controlled substance with no medical uses according to US federal law. The perception of cannabis depends on social and cultural norms that impact political institutions involved in implementing policy. Because of negative social constructions, such as the "gateway hypothesis," legalization of cannabis has been slow and contentious. Recent studies suggest that cannabis can help combat the opioid epidemic. This paper fills a gap in our understanding of how cannabis is viewed by people who are actively misusing opioids and not in treatment. Using ethnographic methods to recruit participants living in a state that legalized cannabis and a state where cannabis was illegal, survey and interview data were analyzed informed by a social constructionist lens. Findings from their "insider perspective" suggest that for some people struggling with problematic opioid use, cannabis can be beneficial.

Cannabis Significantly Reduces the Use of Prescription Opioids and Improves Quality of Life in Authorized Patients: Results of a Large Prospective Study

OBJECTIVES

This article presents findings from a large prospective examination of Canadian medical cannabis patients, with a focus on the impacts of cannabis on prescription opioid use and quality of life over a 6-month period.

METHODS

The Tilray Observational Patient Study took place at 21 medical clinics throughout Canada. This analysis includes 1,145 patients who had at least one postbaseline visit, with follow-up at 1, 3, and 6 months. Instruments included a comprehensive cannabis use inventory, the World Health Organization Quality of Life Short Form (WHOQOL-BREF), and a detailed prescription drug questionnaire.

RESULTS

Participants were 57.6% female, with a median age of 52 years. Baseline opioid use was reported by 28% of participants, dropping to 11% at 6 months. Daily opioid use went from 152 mg morphine milligram equivalent (MME) at baseline to 32.2 mg MME at 6 months, a 78% reduction in mean opioid dosage. Similar reductions were also seen in the other four primary prescription drug classes identified by participants, and statistically significant improvements were reported in all four domains of the WHOQOL-BREF.

CONCLUSIONS

This study provides an individual-level perspective of cannabis substitution for opioids and other prescription drugs, as well as associated improvement in quality of life over 6 months. The high rate of cannabis use for chronic pain and the subsequent reductions in opioid use suggest that cannabis may play a harm reduction role in the opioid overdose crisis, potentially improving the quality of life of patients and overall public health.

Medical Cannabis for the Management of Pain and Quality of Life in Chronic Pain Patients: A Prospective Observational Study

OBJECTIVE

To evaluate the short-term and long-term effects of plant-based medical cannabis in a chronic pain population over the course of one year.

DESIGN

A longitudinal, prospective, 12-month observational study.

SETTING

Patients were recruited and treated at a clinic specializing in medical cannabis care from October 2015 to March 2019.

SUBJECTS

A total of 751 chronic pain patients initiating medical cannabis treatment.

METHODS

Study participants completed the Brief Pain Inventory and the 12-item Short Form Survey (SF-12), as well as surveys on opioid medication use and adverse events, at baseline and once a month for 12 months.

RESULTS

Medical cannabis treatment was associated with improvements in pain severity and interference (P < 0.001) observed at one month and maintained over the 12-month observation period. Significant improvements were also observed in the SF-12 physical and mental health domains (P < 0.002) starting at three months. Significant decreases in headaches, fatigue, anxiety, and nausea were observed after initiation of treatment (P ≤ 0.002). In patients who reported opioid medication use at baseline, there were significant reductions in oral morphine equivalent doses (P < 0.0001), while correlates of pain were significantly improved by the end of the study observation period.

CONCLUSIONS

Taken together, the findings of this study add to the cumulative evidence in support of plant-based medical cannabis as a safe and effective treatment option and potential opioid medication substitute or augmentation therapy for the management of symptoms and quality of life in chronic pain patients.

Cannabis use in patients treated for opioid use disorder pre- and post-recreational cannabis legalization in Canada

Background

As the legalization of recreational cannabis becomes more widespread, its impact on individuals with substance use disorders must be studied. Amidst an ongoing opioid crisis, Canada’s legalization of recreational cannabis in October 2018 provides an important setting for investigation. We examined changes to cannabis use patterns in patients receiving medication-assisted treatment (MAT) for opioid use disorder (OUD) following legalization.

Methods

This study includes cross-sectional data from 602 participants recruited 6 months pre-legalization and 788 participants recruited 6 months post-legalization, providing information on cannabis use. Regression analysis was used to estimate the association between legalization and cannabis use patterns. We collected longitudinal urine drug screens (UDSs) detecting cannabis-metabolites for 199 participants recruited pre-legalization and followed prospectively post-legalization. Conditional logistic regression was used to assess the association between legalization and UDS results.

Results

Past-month cannabis use was self-reported by 54.8 and 52.3% of participants recruited pre- and post-legalization, respectively. Legalization was not associated with changes in any measured cannabis characteristics: cannabis use (OR 0.91, 95% CI 0.73–1.13), days of use/month (B -0.42, 95% CI - 2.05-1.21), money spent, or cannabis source. There was no association between legalization and prevalence of cannabis use on UDS (OR 1.67, 95% CI 0.93–2.99) or percentage of cannabis-positive UDSs (OR 1.00, 95% CI 0.99–1.01). Participants overwhelmingly reported that legalization would have no impact on their cannabis use (85.7%).

Conclusions

Amongst patients treated for OUD, no significant change in cannabis use was observed following legalization; however, high rates of cannabis use are noted.

Factors associated with health-related cannabis use intentions among a community sample of people who inject drugs in Los Angeles and San Francisco, CA 2016 to 2018

OBJECTIVE

Cannabis motivations have been studied extensively among patients of medicinal cannabis dispensaries, but less is known about motivations in community samples of opioid-using people who inject drugs. Our objective is to describe cannabis use motivations associated with self-treatment of physical pain, emotional issues, and as an opioid substitute.

METHODS

Data come from 6-month follow-up interviews with people who inject drugs who participated in a study on the efficacy of an injection initiation prevention intervention in Los Angeles and San Francisco, California from 2016-18. The analytic sample consists of 387 people who inject drugs who reported past-month cannabis use. We developed multivariable logistic regression models by reported cannabis use motivations: physical pain relief, emotional problems, and opioid substitute.

RESULTS

The most common cannabis use motivations reported by people who inject drugs was to "get high," relieve physical pain and emotional problems, and reduce opioid use. In separate multivariate models, using cannabis for physical pain relief was associated with higher odds of using cannabis as a substitute for opioids; cannabis for emotional problems was associated with being diagnosed with depression; and cannabis as a substitute for opioids was associated with non-prescribed, non-injection methadone use.

CONCLUSION

People who inject drugs reported using cannabis for health-related motivations. This motivation aligns with health needs and suggests the acceptability of cannabis use for health reasons in this population. Studies to determine the medical effectiveness of cannabis products for these common health and mental health needs among people who inject drugs are needed.

Prospects for the Use of Cannabinoids in Psychiatric Disorders

Increasing evidence suggests an essential role of the endocannabinoid system in modulating cognitive abilities, mood, stress, and sleep. The psychoactive effects of cannabis are described as euphoric, calming, anxiolytic, and sleep-inducing and positively affect the mood, but can also adversely affect therapy. The responses to cannabinoid medications depend on the patient's endocannabinoid system activity, the proportion of phytocannabinoids, the terpenoid composition, and the dose used. There is some evidence for a therapeutic use of phytocannabinoids in psychiatric conditions. THC and CBD may have opposing effects on anxiety. Current guidelines recommend caution in using THC in patients with anxiety or mood disorders. In a small number of clinical trials, cannabinoids used to treat cancer, HIV, multiple sclerosis, hepatitis C, Crohn's disease, and chronic neuropathic pain report decreases in anxiety or depression symptoms and presented sedative and anxiolytic effects. Several studies have investigated the influence of potential genetic factors on psychosis and schizophrenia development after cannabis use. THC may increase the risk of psychosis, especially in young patients with an immature central nervous system. There is limited evidence from clinical trials that cannabinoids are effective therapy for sleep disorders associated with concomitant conditions. There is evidence for a possible role of cannabis as a substitute for alcohol and drugs, also in the context of the risks of opioid use (e.g., opioid-related mortality). In this narrative review of the recent evidence, we discuss the prospects of using the psychoactive effects of cannabinoids in treating mental and psychiatric disorders. However, this evidence is weak for some clinical conditions and well-designed randomized controlled trials are currently lacking. Furthermore, some disorders may be worsened by cannabis use.

Cannabis Use and Nonfatal Opioid Overdose among Patients Enrolled in Methadone Maintenance Treatment

BACKGROUND

Some ecological studies found lower rates of opioid overdose in states with liberalized cannabis legislation, but results are mixed, and the association has not been analyzed in individuals. We quantified the association between cannabis use and nonfatal opioid overdose among individuals enrolled in methadone maintenance treatment (MMT) for opioid use disorder (OUD).

METHODS

We recruited a convenience sample of individuals enrolled in four MMT clinics in Washington State and southern New England who completed a one-time survey.Descriptive statistics and multivariate logistic regression compared the prevalence and risk of nonfatal opioid overdose in the past 12 months between participants reporting frequent (at least weekly) or infrequent (once or none) cannabis use in the past month.

RESULTS

Of 446 participants, 35% (n = 156) reported frequent cannabis use and 7% (n = 32) reported nonfatal opioid overdose in the past year. The prevalence of nonfatal opioid overdose was 3% among reporters of frequent cannabis use, and 9% among reporters of infrequent/no use (p = 0.02). After imputing missing data and controlling for demographic and clinical factors, the likelihood of self-reported nonfatal opioid overdose in the past year was 71% lower among reporters of frequent cannabis use in the past month (adjusted RR = 0.29, 95% CI 0.10-0.80, p = 0.02).

CONCLUSIONS

Among individuals enrolled in MMT, frequent cannabis use in the past month was associated with fewer self-reported nonfatal opioid overdoses in the past year. Methodological limitations caution against causal interpretation of this relationship. Additional studies are needed to understand the prospective impact of co-occurring cannabis on opioid-related outcomes.

The relationship between cannabis use and patient outcomes in medication-based treatment of opioid use disorder: A systematic review

Despite high rates of cannabis use during medication-based treatment of opioid use disorder (MOUD), uncertainty remains around how cannabis influences treatment outcomes. We sought to investigate the relationship between cannabis use during MOUD and a number of patient outcomes. We searched seven databases for original peer-reviewed studies documenting the relationship between cannabis use and at least one primary outcome (opioid use, treatment adherence, or treatment retention) among patients enrolled in methadone-, buprenorphine-, or naltrexone-based therapy for OUD. In total, 41 articles (including 23 methadone, 7 buprenorphine, 6 naltrexone, and 5 mixed modalities) were included in this review. For each primary outcome area, there was a small number of studies that produced findings suggestive of a supportive or detrimental role of concurrent cannabis use, but the majority of studies reported that cannabis use was not statistically significantly associated with the outcome. No studies of naltrexone treatment demonstrated significantly worse outcomes for cannabis users. We identified methodological shortcomings and future research priorities, including exploring the potential role of adjunct cannabis use for improving opioid craving and withdrawal during MOUD. While monitoring for cannabis use may help guide clinicians towards an improved treatment plan, cannabis use is unlikely to independently threaten treatment outcomes.

"That's No Longer Tolerated": Policing Patients' Use of Non-opioid Substances in Methadone Maintenance Treatment

The current overdose crisis in the United States emphasizes the importance of providing substance use treatment programs that are not only effective but tailored to meet the specific needs of the populations they serve. While Methadone Maintenance Treatment (MMT) is considered to be among the best strategies for reducing rates of opioid-involved overdose, its ability to attract and maintain patients may be hindered by a recent focus on policing the non-opioid substance use of people on the program. This paper uses interview data from treatment providers to examine how clinicians conceptualize and organize MMT in regards to patients' use of non-opioid drugs. Responses demonstrate that some treatment providers are increasingly monitoring their patients' use of non-opioid substances and punishing them for infractions, up to and including discharge from treatment. This approach will likely result in increasing rates of patient dropout and a lack of new admissions among people who use non-opioid substances. This article argues that including non-opioid substances in MMT's mandate restricts its ability to improve public health, including by preventing overdoses, and recommends instead that MMT adopt a more individualized approach, shaped by the needs and goals of the patient rather than those of the clinician.

The association of cannabis use late in pregnancy with engagement and retention in perinatal substance use disorder care for opioid use disorder: A cohort comparison

BACKGROUND

Prenatal use of cannabis and opioids are increasing and very concerning. Engagement and retention in comprehensive, perinatal substance use disorder (PSUD) care are associated with better outcomes for mothers and babies. We compared the characteristics and engagement in care among women with opioid use disorder who used cannabis late in pregnancy versus those who didn't.

METHODS

The primary outcome, "overall engagement and retention in PSUD care" included: utilization of substance use treatment prenatally, negative screening/toxicology at delivery (excluding cannabis), and attendance at expected prenatal and postpartum visits. Cannabis use late in pregnancy was objectively assessed at delivery via maternal urine drug screen and/or neonatal meconium/cord toxicology. Between-group comparisons utilized chi square, t-test or Mann-Whitney. Associations were assessed using Spearman Rho and two multivariate, binary logistic regressions for cannabis use and the primary outcome.

RESULTS

18.0% (85/472) consumed cannabis late in pregnancy. Women of color, younger women, and those diagnosed with concurrent cannabis use disorder were more likely to consume cannabis. Engagement and retention in PSUD care was not associated with cannabis use, but rather, with prescribed pharmacotherapy for psychiatric disorders. The use of prescribed buprenorphine+naloxone was associated with cannabis avoidance late in pregnancy.

CONCLUSIONS

Cannabis use late in pregnancy, compared to none, did not impact engagement and retention in our PSUD program. Adjunctive psychotropic medication and/or buprenorphine+naloxone prescription were associated with cannabis avoidance suggesting the use and interactions of pharmacotherapies in an opioid dependent population is complex. A shared decision-making process during PSUD care is warranted.

The emergence of innovative cannabis distribution projects in the downtown eastside of Vancouver, Canada

The ongoing overdose crisis in the United States and Canada has highlighted the urgent need for innovative interventions to reduce drug-related harms. This, in turn, has led to increased interest in the potential of cannabis as a harm reduction strategy. While Canada has recently legalized cannabis, meaningful barriers to accessing legal cannabis remain for people who use drugs (PWUD) from marginalized communities. In the Downtown Eastside of Vancouver, Canada, innovative, grassroots cannabis distribution programs that dispense cannabis and cannabis products from unregulated sources to PWUD for free have recently emerged. In this study, we draw upon 23 in-depth qualitative interviews and ethnographic fieldwork with PWUD who access these programs. We found that these distribution programs play an important function in bridging access to cannabis for PWUD in a structurally disadvantaged neighborhood and do so by implementing few restrictions on who can access, providing a variety of cannabis products that would otherwise be inaccessible, and distributing cannabis at no cost. In addition, many people reported the program spaces provided an avenue to socialize and connect. Most of our participants reported that legal cannabis was inaccessible both through the legal medical and non-medical systems. Considering Canadian governments have made important regulatory changes in regards to cannabis, understanding emerging patterns and the structural barriers to accessing legal cannabis will be critical to maximizing the potential uses of cannabis as a harm reduction tool and ensuring equitable access to structurally disadvantaged populations. Examining the impact of cannabis use on PWUD and ensuring these groups have access to cannabis is an important component in determining whether cannabis deregulation reduces drug-related harms.

Pregabalin Abuse in Combination With Other Drugs: Monitoring Among Methadone Patients

INTRODUCTION

In recent years, there has been an increase in the non-medical use of psychoactive prescription drugs including pregabalin (PGB). Studies have shown that multiple drug users and patients in methadone treatment programs administered PGB at high dosages in order to achieve euphoria, reduce withdrawal symptoms, or potentiate the effects of methadone. For these reasons, accurate toxicological monitoring is required for these high-risk individuals.

MATERIALS AND METHODS

The present study investigated whether PGB could be detected in the hair samples of 250 patients with a history of opiate dependency, and under toxicological surveillance assess their compliance with methadone maintenance therapy.

RESULTS

Opiates were found in 54/250 of all hair samples, while cannabis was present in 74/250 patients, cocaine was detected in 21/250 patients, and benzodiazepines without prescription were identified in 49/250 patients. As expected, methadone was present in all 250 patients (100%). PGB without prescription was found in the hair samples of 35/250 patients (14%). Of these, 91.43% were male, 48.57% were <30 y old, and 45.71% were between ages 30 and 50 y. There were no apparent associations among PGB use, daily methadone dosage, and duration of methadone maintenance therapy. Psychiatric comorbidities were present in 25.71% of the patients abusing PGB. Anxiety (55.56%) and depression (33.33%) were the most prevalent psychiatric disorders.

DISCUSSION

Most of the patients taking PGB (57.14%) used other drugs (especially opiates) concurrently. The utility of hair analysis is explained by easy and rapid sample collection and the ability of the hair to reflect long-term drug use and incorporate drug metabolites. The findings of this study suggested that PGB has significant potential for abuse by high-risk populations such as opioid users and patients with dual diagnosis. These risks are particularly high in cases of poly-drug use and drug intake that are not in compliance with prescription guidelines.

Trends in Opioid Misuse among Marijuana Users and Non-Users in the U.S. from 2007-2017

Prescription-opioid misus e continues to be a significant health concern in the United States. The relationship between marijuana use and prescription-opioid misuse is not clear from the extant literature. This study examined national trends in prescription-opioid misuse among marijuana users and non-users using the 2007-2017 National Survey on Drug Use and Health. Cochran-Armitage tests were used to assess the statistical significance of changes in the yearly prevalence of prescription-opioid misuse and marijuana use. Multivariable logistic regression was used to examine the association between prescription-opioid and marijuana use adjusting for sociodemographic characteristics. From 2007 to 2017, marijuana use increased, while prescription-opioid misuse declined. Larger declines in prescription-opioid misuse were found among marijuana users than non-users. Marijuana ever-use was significantly associated with prescription-opioid misuse. Specifically, marijuana ever-users had higher odds of prescription-opioid misuse (ever-misuse [OR: 3.04; 95% CI, 2.68-3.43]; past-year misuse [OR: 3.44; 95% CI, 3.00-3.94]; and past-month misuse [OR: 4.50; 95% CI, 3.35-6.05]) compared to marijuana never-users. Similar results were found for the association of past-year and past-month marijuana use with prescription-opioid misuse. This study provides data on trends and associations about opioid misuse among marijuana users and non-users in a changing social environment of drug use in the United States. Future research should consider whether there is a causal relationship between marijuana use and prescription opioid misuse.

Does Cannabis Use Influence Opioid Outcomes and Quality of Life Among Buprenorphine Maintained Patients? A Cross-sectional, Comparative Study

OBJECTIVES

Use of various psychoactive substances can influence outcomes of patients on opioid agonist treatment (OAT). While use of alcohol and cocaine has shown to adversely affect OAT results, associated cannabis use shows mixed results. This study aimed to assess the pattern of cannabis use among opioid-dependent patients maintained on buprenorphine. Additionally, the study compared the dose of buprenorphine, opioid-related craving and withdrawals, productivity, and also quality of life between those with and without recent (past 90-day) cannabis use.

METHODS

We collected data on demographic and drug use details in 100 randomly selected adult male patients attending a community drug treatment clinic, who were stabilized on buprenorphine for more than 3 months. Other measures included scores on World Health Organization (WHO)-Alcohol, Smoking and Substance Involvement Screening Tool and WHO-Quality of Life-Brief (WHOQOL-Bref) version.

RESULTS

The average duration of maintenance treatment with buprenorphine was 96 months, with excellent compliance for buprenorphine (86.92 ± 9.58 days in 90 days). Thirty-five per cent had used cannabis in past 90 days, with lifetime use of cannabis in 77%. Participants using cannabis currently were on lower doses of buprenorphine (mean dose per day: 7.9 mg vs 8.9 mg; P = 0.04). Yet, there was no significant difference in the rates of opioid use or opioid withdrawals and craving between the 2 groups. Compliance to OAT, number of days of employment, daily earning, and WHOQOL-Bref scores in all domains were comparable between those with and without cannabis use. Duration of cannabis use, current use of alcohol, and dose of buprenorphine predicted current cannabis use in multivariable logistic regression analysis.

CONCLUSIONS

Cannabis use does not negatively influence opioid outcomes among patients receiving buprenorphine maintenance treatment. There is no difference in productivity and quality of life between individuals maintained on buprenorphine with and without current cannabis use.

The association between health conditions and cannabis use in patients with opioid use disorder receiving methadone maintenance treatment

BACKGROUND

Cannabis is the most commonly used substance among patients in methadone maintenance treatment (MMT) for opioid use disorder. Current treatment programmes neither screen nor manage cannabis use. The recent legalisation of cannabis in Canada incites consideration into how this may affect the current opioid crisis.

AIMS

Investigate the health status of cannabis users in MMT.

METHOD

Patients were recruited from addiction clinics in Ontario, Canada. Regression analyses were used to assess the association between adverse health conditions and cannabis use. Further analyses were used to assess sex differences and heaviness of cannabis use.

RESULTS

We included 672 patients (49.9% cannabis users). Cannabis users were more likely to consume alcohol (odds ratio 1.46, 95% CI 1.04-2.06, P = 0.029) and have anxiety disorders (odds ratio 1.75, 95% CI 1.02-3.02, P = 0.043), but were less likely to use heroin (odds ratio 0.45, 95% CI 0.24-0.86, P = 0.016). There was no association between cannabis use and pain (odds ratio 0.98, 95% CI 0.94-1.03, P = 0.463). A significant association was seen between alcohol and cannabis use in women (odds ratio 1.79, 95% CI 1.06-3.02, P = 0.028), and anxiety disorders and cannabis use in men (odds ratio 2.59, 95% CI 1.21-5.53, P = 0.014). Heaviness of cannabis use was not associated with health outcomes.

CONCLUSIONS

Our results suggest that cannabis use is common and associated with psychiatric comorbidities and substance use among patients in MMT, advocating for screening of cannabis use in this population.

DECLARATION OF INTEREST

None.

Cannabis use during methadone maintenance treatment for opioid use disorder: a systematic review and meta-analysis

BACKGROUND

Rates of cannabis use among patients receiving methadone maintenance therapy are high, and cannabis use may be associated with outcomes of methadone maintenance therapy. We examined the effect of cannabis use on opioid use in patients receiving methadone maintenance therapy to test the hypothesis that cannabis use is associated with a reduction in opioid use.

METHODS

In this systematic review, we searched MEDLINE/PubMed, Embase, PsycINFO, CINAHL and ProQuest Dissertations and Theses Global from inception to July 12, 2018. We summarized the effects of cannabis use on opioid use during methadone maintenance therapy and treatment retention. We conducted meta-analyses using a random effects model.

RESULTS

We included 23 studies in our review. We performed a meta-analysis of 6 studies, with a total number of participants of 3676, examining use of cannabis and opioids during methadone maintenance therapy. Owing to high heterogeneity, we described the studies qualitatively but provide the forest plots as supplemental material. The overall quality of evidence was very low, with a high risk of bias, owing to the nature of observational studies.

INTERPRETATION

We found no consensus among studies that cannabis use is associated with reduced opioid use or longer treatment retention when used during methadone maintenance therapy in patients with opioid use disorder. PROSPERO Registration: CRD42015029372.

Reduced urinary opioid levels from pain management patients associated with marijuana use

Aim: Marijuana use has been postulated to modulate opioid use, dependence and withdrawal. Broad target drug testing results provide a unique perspective to identify any potential interaction between marijuana use and opioid use. Materials & methods: Using a dataset of approximately 800,000 urine drug test results collected from pain management patients of a time from of multiple years, creatinine corrected opioid levels were evaluated to determine if the presence of the primary marijuana marker 11-nor-carboxy-tetrahydrocannabinol (THC-COOH) was associated with statistical differences in excreted opioid concentrations. Results & conclusion: For each of the opioids investigated (codeine, morphine, hydrocodone, hydromorphone, oxycodone, oxymorphone, fentanyl and buprenorphine), marijuana use was associated with statistically significant lower urinary opiate levels than in samples without indicators of marijuana use.

Medicinal Properties of Cannabinoids, Terpenes, and Flavonoids in Cannabis, and Benefits in Migraine, Headache, and Pain: An Update on Current Evidence and Cannabis Science

BACKGROUND

Comprehensive literature reviews of historical perspectives and evidence supporting cannabis/cannabinoids in the treatment of pain, including migraine and headache, with associated neurobiological mechanisms of pain modulation have been well described. Most of the existing literature reports on the cannabinoids Δ⁹ -tetrahydrocannabinol (THC) and cannabidiol (CBD), or cannabis in general. There are many cannabis strains that vary widely in the composition of cannabinoids, terpenes, flavonoids, and other compounds. These components work synergistically to produce wide variations in benefits, side effects, and strain characteristics. Knowledge of the individual medicinal properties of the cannabinoids, terpenes, and flavonoids is necessary to cross-breed strains to obtain optimal standardized synergistic compositions. This will enable targeting individual symptoms and/or diseases, including migraine, headache, and pain.

OBJECTIVE

Review the medical literature for the use of cannabis/cannabinoids in the treatment of migraine, headache, facial pain, and other chronic pain syndromes, and for supporting evidence of a potential role in combatting the opioid epidemic. Review the medical literature involving major and minor cannabinoids, primary and secondary terpenes, and flavonoids that underlie the synergistic entourage effects of cannabis. Summarize the individual medicinal benefits of these substances, including analgesic and anti-inflammatory properties.

CONCLUSION

There is accumulating evidence for various therapeutic benefits of cannabis/cannabinoids, especially in the treatment of pain, which may also apply to the treatment of migraine and headache. There is also supporting evidence that cannabis may assist in opioid detoxification and weaning, thus making it a potential weapon in battling the opioid epidemic. Cannabis science is a rapidly evolving medical sector and industry with increasingly regulated production standards. Further research is anticipated to optimize breeding of strain-specific synergistic ratios of cannabinoids, terpenes, and other phytochemicals for predictable user effects, characteristics, and improved symptom and disease-targeted therapies.

Medical cannabis patterns of use and substitution for opioids & other pharmaceutical drugs, alcohol, tobacco, and illicit substances; results from a cross-sectional survey of authorized patients

BACKGROUND

A 239-question cross-sectional survey was sent out via email in January 2017 to gather comprehensive information on cannabis use from Canadian medical cannabis patients registered with a federally authorized licensed cannabis producer, resulting in 2032 complete surveys.

METHODS

The survey gathered detailed demographic data and comprehensive information on patient patterns of medical cannabis use, including questions assessing the self-reported impact of cannabis on the use of prescription drugs, illicit substances, alcohol, and tobacco.

RESULTS

Participants were 62.6% male (n = 1271) and 91% Caucasian (n = 1839). The mean age was 40 years old, and pain and mental health conditions accounted for 83.7% of all respondents (n = 1700). Then, 74.6% of respondents reported daily cannabis use (n = 1515) and mean amount used per day was 1.5 g. The most commonly cited substitution was for prescription drugs (69.1%, n = 953), followed by alcohol (44.5%, n = 515), tobacco (31.1%, n = 406), and illicit substances (26.6%, n = 136). Opioid medications accounted for 35.3% of all prescription drug substitution (n = 610), followed by antidepressants (21.5%, n = 371). Of the 610 mentions of specific opioid medications, patients report total cessation of use of 59.3% (n = 362).

CONCLUSIONS

This study offers a unique perspective by focusing on the use of a standardized, government-regulated source of medical cannabis by patients registered in Canada's federal medical cannabis program. The findings provide a granular view of patient patterns of medical cannabis use, and the subsequent self-reported impacts on the use of opioids, alcohol, and other substances, adding to a growing body of academic research suggesting that increased regulated access to medical and recreational cannabis can result in a reduction in the use of and subsequent harms associated with opioids, alcohol, tobacco, and other substances.

High-intensity cannabis use is associated with retention in opioid agonist treatment: a longitudinal analysis

BACKGROUND AND AIMS

Cannabis use is common among people on opioid agonist treatment (OAT), causing concern for some care providers. However, there is limited and conflicting evidence on the impact of cannabis use on OAT outcomes. Given the critical role of retention in OAT in reducing opioid-related morbidity and mortality, we aimed to estimate the association of at least daily cannabis use on the likelihood of retention in treatment among people initiating OAT. As a secondary aim we tested the impacts of less frequent cannabis use.

DESIGN

Data were drawn from two community-recruited prospective cohorts of people who use illicit drugs (PWUD). Participants were followed for a median of 81 months (interquartile range = 37-130).

SETTING

Vancouver, Canada.

PARTICIPANTS

This study comprised a total of 820 PWUD (57.8% men, 59.4% of Caucasian ethnicity, 32.2% HIV-positive) initiating OAT between December 1996 and May 2016. The proportion of women was higher among HIV-negative participants, with no other significant differences.

MEASUREMENTS

The primary outcome was retention in OAT, defined as remaining in OAT (methadone or buprenorphine/naloxone-based) for two consecutive 6-month follow-up periods. The primary explanatory variable was cannabis use (at least daily versus less than daily) during the same 6-month period. Confounders assessed included: socio-demographic characteristics, substance use patterns and social-structural exposures.

FINDINGS

In adjusted analysis, at least daily cannabis use was positively associated with retention in OAT [adjusted odds ratio (aOR) = 1.21, 95% confidence interval (CI) = 1.04-1.41]. Our secondary analysis showed that compared with non-cannabis users, at least daily users had increased odds of retention in OAT (aOR = 1.20, 95% CI = 1.02-1.43), but not less than daily users (aOR = 1.00, 95% CI = 0.87-1.14).

CONCLUSIONS

Among people who use illicit drugs initiating opioid agonist treatment in Vancouver, at least daily cannabis use was associated with approximately 21% greater odds of retention in treatment compared with less than daily consumption.

Commentary on Socias et al. (2018): Clinical research perspectives on cannabis use in opioid agonist treatment

Research is needed to determine clinical criteria as to who should be using cannabis therapeutically, how to implement therapeutic use of cannabis in opioid agonist treatment (OAT) settings optimally, and other behavioral approaches to improving OAT retention and outcomes.

Patterns of medicinal cannabis use, strain analysis, and substitution effect among patients with migraine, headache, arthritis, and chronic pain in a medicinal cannabis cohort

BACKGROUND

Medicinal cannabis registries typically report pain as the most common reason for use. It would be clinically useful to identify patterns of cannabis treatment in migraine and headache, as compared to arthritis and chronic pain, and to analyze preferred cannabis strains, biochemical profiles, and prescription medication substitutions with cannabis.

METHODS

Via electronic survey in medicinal cannabis patients with headache, arthritis, and chronic pain, demographics and patterns of cannabis use including methods, frequency, quantity, preferred strains, cannabinoid and terpene profiles, and prescription substitutions were recorded. Cannabis use for migraine among headache patients was assessed via the ID Migraine™ questionnaire, a validated screen used to predict the probability of migraine.

RESULTS

Of 2032 patients, 21 illnesses were treated with cannabis. Pain syndromes accounted for 42.4% (n = 861) overall; chronic pain 29.4% (n = 598;), arthritis 9.3% (n = 188), and headache 3.7% (n = 75;). Across all 21 illnesses, headache was a symptom treated with cannabis in 24.9% (n = 505). These patients were given the ID Migraine™ questionnaire, with 68% (n = 343) giving 3 "Yes" responses, 20% (n = 102) giving 2 "Yes" responses (97% and 93% probability of migraine, respectively). Therefore, 88% (n = 445) of headache patients were treating probable migraine with cannabis. Hybrid strains were most preferred across all pain subtypes, with "OG Shark" the most preferred strain in the ID Migraine™ and headache groups. Many pain patients substituted prescription medications with cannabis (41.2-59.5%), most commonly opiates/opioids (40.5-72.8%). Prescription substitution in headache patients included opiates/opioids (43.4%), anti-depressant/anti-anxiety (39%), NSAIDs (21%), triptans (8.1%), anti-convulsants (7.7%), muscle relaxers (7%), ergots (0.4%).

CONCLUSIONS

Chronic pain was the most common reason for cannabis use, consistent with most registries. The majority of headache patients treating with cannabis were positive for migraine. Hybrid strains were preferred in ID Migraine™, headache, and most pain groups, with "OG Shark", a high THC (Δ9-tetrahydrocannabinol)/THCA (tetrahydrocannabinolic acid), low CBD (cannabidiol)/CBDA (cannabidiolic acid), strain with predominant terpenes β-caryophyllene and β-myrcene, most preferred in the headache and ID Migraine™ groups. This could reflect the potent analgesic, anti-inflammatory, and anti-emetic properties of THC, with anti-inflammatory and analgesic properties of β-caryophyllene and β-myrcene. Opiates/opioids were most commonly substituted with cannabis. Prospective studies are needed, but results may provide early insight into optimizing crossbred cannabis strains, synergistic biochemical profiles, dosing, and patterns of use in the treatment of headache, migraine, and chronic pain syndromes.

The role of cannabinoids in pain control: the good, the bad, and the ugly

Cannabinoids appear to possess many potential medical uses, which may extend to pain control. A narrative review of the literature has found a variety of studies testing botanical and synthetic cannabinoids in different pain syndromes (acute pain, cancer pain, chronic noncancer pain, fibromyalgia pain, migraine, neuropathic pain, visceral pain, and others). Results from these studies are mixed; cannabinoids appear to be most effective in controlling neuropathic pain, allodynia, medication-rebound headache, and chronic noncancer pain, but do not seem to offer any advantage over nonopioid analgesics for acute pain. Cannabinoids seem to work no better than placebo for visceral pain and conferred only modest analgesic effect in cancer pain. Cannabinoids do many good things - they appear to be effective in treating certain types of pain without the issues of tolerance associated with opioids. Negatively, marijuana currently has a very murky legal status all over the world - laws regulating its use are inconsistent and in flux. Thus, both patients and prescribers may be unsure about whether or not it is an appropriate form of pain control. Cannabinoid-based analgesia has been linked to potential memory deficits and cognitive impairment. A great deal more remains to be elucidated about cannabinoids which may emerge to play an important role in the treatment of neuropathic and possibly other painful conditions. There remains a great deal more to learn about the role of cannabinoids in pain management.

The impact of cannabis use on patients enrolled in opioid agonist therapy in Ontario, Canada

Background

With the Canadian government legalizing cannabis in the year 2018, the potential harms to certain populations—including those with opioid use disorder—must be investigated. Cannabis is one of the most commonly used substances by patients who are engaged in medication-assisted treatment for opioid use disorder, the effects of which are largely unknown. In this study, we examine the impact of baseline and ongoing cannabis use, and whether these are impacted differentially by gender.

Methods

We conducted a retrospective cohort study using anonymized electronic medical records from 58 clinics offering opioid agonist therapy in Ontario, Canada. One-year treatment retention was the primary outcome of interest and was measured for patients who did and did not have a cannabis positive urine sample in their first month of treatment, and as a function of the proportion of cannabis-positive urine samples throughout treatment.

Results

Our cohort consisted of 644 patients, 328 of which were considered baseline cannabis users and 256 considered heavy users. Patients with baseline cannabis use and heavy cannabis use were at increased risk of dropout (38.9% and 48.1%, respectively). When evaluating these trends by gender, only female baseline users and male heavy users are at increased risk of premature dropout.

Interpretation

Both baseline and heavy cannabis use are predictive of decreased treatment retention, and differences do exist between genders. With cannabis being legalized in the near future, physicians should closely monitor cannabis-using patients and provide education surrounding the potential harms of using cannabis while receiving treatment for opioid use disorder.

Cessation of Injecting and Preceding Drug Use Patterns Among a Prospective Cohort of Street-Involved Youth

PURPOSE

Injection drug use is prevalent among street-involved youth, but patterns of cessation are poorly described. We identified drug use patterns preceding injection cessation among street-involved youth.

METHODS

From September 2005 to May 2015, we collected data from the At-Risk Youth Study, a prospective cohort of street-involved youth in Vancouver, Canada, and limited the sample to actively injecting youth. The primary outcome was cessation of injecting self-reported at semiannual follow-up visits. We used Cox regression to identify drug use patterns preceding cessation.

RESULTS

Among 383 youth, 65% were male, mean age was 22.3 (standard deviation, 2.5; range, 15-30) years, and 171 (45%) ceased injecting for 6 months or more (crude incidence density 22 per 100 person-years; 95% confidence interval [CI], 19-26). Youth who ceased were less likely to have injected daily (adjusted hazard ratio [AHR], .40; 95% CI, .28-.56), injected heroin (AHR, .40; 95% CI, .29-.56), or injected crystal methamphetamine (AHR, .43; 95% CI, .31-.59) before cessation. Noninjection heroin use was positively associated with injection cessation (AHR, 1.52; 95 CI, 1.12-2.08). Addiction treatment was not associated with cessation. At the time of cessation, 101 (59%) youth continued to use "hard" noninjection drugs such as heroin and crystal methamphetamine.

CONCLUSIONS

Periods of injection cessation were common but frequently accompanied by ongoing noninjection drug use. Findings indicate that trajectories of injection drug use among youth are complex and highlight the need to further explore relationships between ongoing noninjection drug use and injection cessation.

Rationale for cannabis-based interventions in the opioid overdose crisis

Background

North America is currently in the grips of a crisis rooted in the use of licit and illicit opioid-based analgesics. Drug overdose is the leading cause of accidental death in Canada and the US, and the growing toll of opioid-related morbidity and mortality requires a diversity of novel therapeutic and harm reduction-based interventions. Research suggests that increasing adult access to both medical and recreational cannabis has significant positive impacts on public health and safety as a result of substitution effect. Observational and epidemiological studies have found that medical cannabis programs are associated with a reduction in the use of opioids and associated morbidity and mortality.

Aims and Methods

This paper presents an evidence-based rationale for cannabis-based interventions in the opioid overdose crisis informed by research on substitution effect, proposing three important windows of opportunity for cannabis for therapeutic purposes (CTP) to play a role in reducing opioid use and interrupting the cycle towards opioid use disorder: 1) prior to opioid introduction in the treatment of chronic pain; 2) as an opioid reduction strategy for those patients already using opioids; and 3) as an adjunct therapy to methadone or suboxone treatment in order to increase treatment success rates. The commentary explores potential obstacles and limitations to these proposed interventions, and as well as strategies to monitor their impact on public health and safety.

Conclusion

The growing body of research supporting the medical use of cannabis as an adjunct or substitute for opioids creates an evidence-based rationale for governments, health care providers, and academic researchers to consider the implementation and assessment of cannabis-based interventions in the opioid crisis.

Association between cannabis use and methadone maintenance treatment outcomes: an investigation into sex differences

Background

Cannabis will soon become legalized in Canada, and it is currently unclear how this will impact public health. Methadone maintenance treatment (MMT) is the most common pharmacological treatment for opioid use disorder (OUD), and despite its documented effectiveness, a large number of patients respond poorly and experience relapse to illicit opioids. Some studies implicate cannabis use as a risk factor for poor MMT response. Although it is well established that substance-use behaviors differ by sex, few of these studies have considered sex as a potential moderator. The current study aims to investigate sex differences in the association between cannabis use and illicit opioid use in a cohort of MMT patients.

Methods

This multicentre study recruited participants on MMT for OUD from Canadian Addiction Treatment Centre sites in Ontario, Canada. Sex differences in the association between any cannabis use and illicit opioid use were investigated using multivariable logistic regression. A secondary analysis was conducted to investigate the association with heaviness of cannabis use.

Results

The study included 414 men and 363 women with OUD receiving MMT. Cannabis use was significantly associated with illicit opioid use in women only (OR = 1.82, 95% CI 1.18, 2.82, p = 0.007). Heaviness of cannabis use was not associated with illicit opioid use in men or women.

Conclusions

This is the largest study to date examining the association between cannabis use and illicit opioid use. Cannabis use may be a sex-specific predictor of poor response to MMT, such that women are more likely to use illicit opioids if they also use cannabis during treatment. Women may show improved treatment outcomes if cannabis use is addressed during MMT.

Impact of Cannabis Use on Treatment Outcomes among Adults Receiving Cognitive-Behavioral Treatment for PTSD and Substance Use Disorders

BACKGROUND

Research has demonstrated a strong link between trauma, posttraumatic stress disorder PTSD and substance use disorders (SUDs) in general and cannabis use disorders in particular. Yet, few studies have examined the impact of cannabis use on treatment outcomes for individuals with co-occurring PTSD and SUDs.

METHODS

Participants were 136 individuals who received cognitive-behavioral therapies for co-occurring PTSD and SUD. Multivariate regressions were utilized to examine the associations between baseline cannabis use and end-of-treatment outcomes. Multilevel linear growth models were fit to the data to examine the cross-lagged associations between weekly cannabis use and weekly PTSD symptom severity and primary substance use during treatment.

RESULTS

There were no significant positive nor negative associations between baseline cannabis use and end-of-treatment PTSD symptom severity and days of primary substance use. Cross-lagged models revealed that as cannabis use increased, subsequent primary substance use decreased and vice versa. Moreover, results revealed a crossover lagged effect, whereby higher cannabis use was associated with greater PTSD symptom severity early in treatment, but lower weekly PTSD symptom severity later in treatment.

CONCLUSION

Cannabis use was not associated with adverse outcomes in end-of-treatment PTSD and primary substance use, suggesting independent pathways of change. The theoretical and clinical implications of the reciprocal associations between weekly cannabis use and subsequent PTSD and primary substance use symptoms during treatment are discussed.

The impact of comorbid psychiatric disorders on methadone maintenance treatment in opioid use disorder: a prospective cohort study

OBJECTIVE

There is a significant interindividual variability in treatment outcomes in methadone maintenance treatment (MMT) for opioid use disorder (OUD). This prospective cohort study examines the impact of comorbid psychiatric disorders on continued illicit opioid use in patients receiving MMT for OUD.

METHODS

Data were collected from 935 patients receiving MMT in outpatient clinics between June 2011 and June 2015. Using linear regression analysis, we evaluated the impact of having a comorbid psychiatric disorder on continued illicit opioid use during MMT, adjusting for important confounders. The main outcome measure was percentage of opioid-positive urine screens for 6 months. We conducted a subgroup analysis to determine the influence of specific comorbid psychiatric disorders, including substance use disorders, on continued illicit opioid use.

RESULTS

Approximately 80% of participants had at least one comorbid psychiatric disorder in addition to OUD, and 42% of participants had a comorbid substance use disorder. There was no significant association between having a psychiatric comorbidity and continuing opioid use (P=0.248). Results from subgroup analysis, however, suggest that comorbid tranquilizer (β=20.781, P<0.001) and cocaine (β=6.344, P=0.031) use disorders are associated with increased rates of continuing opioid use.

CONCLUSION

Results from our study may serve to guide future MMT guidelines. Specifically, we find that cocaine or tranquilizer use disorder, comorbid with OUD, places patients at high risk for poor MMT outcomes. Treatment centers may choose to gear more intensive therapy toward such populations.