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

Pain severity contributes to worse outcomes in opioid use disorder recovery than pain status

BACKGROUND

Opioid use disorder (OUD) continues to pose a significant challenge to public health in the United States. Chronic pain and OUD are highly comorbid conditions, yet few studies have examined the relative associations of pain status and severity toward multidimensional OUD recovery outcomes (e.g., psychopathology and withdrawal).

METHODS

Participants (N = 214) were from the RECOVER-LT study, conducted 4.2-years after completion of a clinical trial program assessing extended-release buprenorphine. Group differences by pain status (i.e., chronic, acute, or no pain) were evaluated in this cross-sectional data set using analysis of variance and Fisher's exact test. Linear regression was utilized to understand the associations between average pain severity and recovery outcomes. Model selection was performed to examine the relative importance of pain status and average pain severity to recovery outcomes.

RESULTS

A majority of the sample endorsed chronic pain (73.8 %). The multivariate regression analysis with model selection found that higher average pain severity (p < .001), but not pain status, was significantly associated with the multidimensional recovery outcomes greater total number of DSM-5 OUD symptoms, higher opioid withdrawal score, reduced physical quality of life, higher depressive symptoms, negative affect, and greater psychological distress. Pain status and average pain severity were not associated with past 7- or 30-day opioid use (p > 0.001).

CONCLUSIONS

These findings highlight pain severity, but not pain status, as a key dimension of OUD recovery. This suggests a need for integration of OUD treatment and pain management, particularly for individuals experiencing elevated pain severity regardless of pain status.

Effects of randomization to buprenorphine or naltrexone for OUD on cannabis use outcomes: A secondary analysis of the X:BOT trial

AIMS

Cannabis use is highly prevalent in patients seeking treatment for opioid use disorder. Studies have shown mixed results on the association between cannabis use and opioid use as well as the impact of MOUD on cannabis use. The current study aims to investigate the effects of buprenorphine versus naltrexone on cannabis use outcomes in treatment seeking individuals with Opioid Use Disorder (OUD).

METHODS

The current study was based on data from the CTN-0051 X:BOT trial, which compared the time to return to significant opioid use survival outcomes of two treatment seeking groups, one receiving Extended-Release Naltrexone (XR-naltrexone) (N = 283) versus another receiving Buprenorphine-Naloxone (N = 287) for OUD. A mixed-effects logistic regression model including treatment assignment (buprenorphine-naloxone vs XR-naltrexone), time, and a time by treatment interaction was run on the sample with the odds of cannabis use as the outcome, as well as two cross-lagged mediation models to explore the prospective mediation of cannabis use on opioid use outcomes (and opioid use on cannabis use outcomes) by treatment assignment during the trial.

RESULTS

There was a significant effect of buprenorphine treatment on reduced cannabis use. Participants receiving buprenorphine treatment were 39 % less likely to use cannabis than those receiving naltrexone over all the timepoints (p = .0499). No significant mediation was found between treatment assignment and opioid use on cannabis use outcomes or between treatment assignment and cannabis use on opioid use outcomes in this trial.

CONCLUSION

Participants in this trial receiving buprenorphine treatment for OUD used less cannabis than those receiving naltrexone treatment.

Associations of discomfort intolerance, discomfort avoidance, and cannabis and alcohol use among persons with chronic pain receiving prescription buprenorphine for opioid use disorder

BACKGROUND

Chronic pain and non-prescribed substance use are associated with lower retention in opioid use disorder (OUD) treatment. We examined the associations of perceived capacity to tolerate uncomfortable physical sensations (discomfort intolerance and discomfort avoidance) and cannabis and alcohol use among persons with chronic pain receiving prescription buprenorphine for OUD.

METHODS

This study utilizes baseline data from 163 persons with chronic pain receiving prescription buprenorphine for OUD enrolled in the Treating Opioid use, Persistent Pain, and Sadness (TOPPS) intervention trial. We used negative-binomial regression models, adjusted for age, education, gender, race/ethnicity, pain interference, depression, generalized anxiety disorder, and average cigarettes smoked/day to estimate the associations of discomfort tolerance and discomfort avoidance with frequency of cannabis and alcohol use.

RESULTS

Participants (n=163) were on average 45 years old (standard deviation=10.6) and predominantly White (86 %, n=141). Forty-one percent (n=66) used cannabis and 24 % (n=30) used alcohol use in the past 30 days. In adjusted models, discomfort intolerance was positively associated with days of cannabis use (IRR = 1.11, p =.016) and days of alcohol use (IRR = 1.14, p =.022). Discomfort avoidance was not associated with cannabis or alcohol use.

CONCLUSION

Individuals with chronic pain receiving prescribed buprenorphine for treatment of OUD with lower tolerance for physical discomfort may augment pain management with cannabis and alcohol. Given the intersections between substance use and retention in care for OUD, future work should extend this preliminary work by exploring these relationships over time and in experimental settings. Clinical Trial # NCT03698669.

A preliminary investigation of the acute effects of delta-9-tetrahydrocannabinol on pain and opioid attentional bias among persons with opioid use disorder

INTRODUCTION

Attentional bias (AB) is believed to be an important factor in the development and maintenance of both opioid use disorder (OUD) and chronic pain. Cannabis and its main psychoactive constituent, delta-9-tetrahydrocannabinol (THC), produce analgesic effects via processes that are potentially relevant to AB and is commonly used by persons with OUD. This exploratory study investigated if THC influences AB towards pain and opioid cues individuals with OUD.

METHODS

Using a within-subject, crossover design, 27 adults receiving methadone were randomly assigned to receive single doses of oral THC (10 mg, 20 mg administered as dronabinol) or placebo across three, 5-h sessions. During each session, a visual probe task was used to measure AB to pain and opioid cues at baseline and 120 min post-THC administration.

RESULTS

Mixed-effects models examined main effects of THC dose, time, and their interaction across all participants; findings were then stratified by methadone dose (low dose <90 mg/day and high dose ≥90 mg/day). Among individuals receiving high doses of methadone, a significant interaction was observed such that AB towards opioids increased following 10 mg THC administration and decreased following 20 mg THC administration. Additionally, participants receiving low doses of methadone showed significant increases in the variability of opioid-related AB post THC administration.

CONCLUSION

We provide preliminary evidence showing that THC may cause dose-dependent effects on selective attention for opioid cues among methadone patients. These results underscore the need for further clinical investigation into the effects of cannabinoids and other substances with potential analgesic and addictive properties among persons with OUD.

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.

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

BACKGROUND

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

METHODS

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

RESULTS

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

CONCLUSION

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

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.

Cannabinoids for Substance Use Disorder Treatment: What Does the Current Evidence Say?

Background: The prevalence of Substance Use Disorder (SUD) is increasing along with the need to develop approaches to reduce the harm associated with substance use, including investigating alternatives such as cannabinoids, which show promising results, although the current evidence is limited. This scoping review focuses on the limitations and potentials of cannabinoid-based treatments for SUDs. Methods: We examined between-subject randomized controlled trials (RCTs) investigating the use of CBD and THC as pharmacological treatment for SUDs in adults, with the procedures attending the expectations of the Preferred Reporting Items for Scoping reviews and Meta-Analyses (PRISMA) for Scoping Reviews guidelines and assessed risk of bias using the Cochrane Risk of Bias Assessment Tool 2. Results: Ten RCTs were included, with six demonstrating low risk of bias, and positive results were found for treating Cannabis Use Disorder, while contradictory results were found for Opioid Use Disorder, and inconclusive results for treating Cocaine Use Disorder. Conclusions: CBD and THC demonstrate potential for treating some SUDs, but evidence is limited. Robust RCTs with larger samples and longer follow-up periods are necessary to assess carefully developed outcomes for different SUD patients. New cannabinoid-based medications and scientific-based policies may advance SUD treatment. A comprehensive approach to treatment and careful methodological choices may benefit patients with SUD.

Longitudinal latent polysubstance use patterns among a cohort of people who use opioids in Vancouver, Canada

INTRODUCTION

Polysubstance use (PSU) practices are increasing among people who use opioids (PWUO). However, several aspects of longitudinal PSU patterns among PWUO remain understudied. This study aims to identify person-centred longitudinal patterns of PSU among a cohort of PWUO.

METHODS

Using longitudinal data (2005-2018) from three prospective cohort studies including people who use drugs in Vancouver, Canada, we used repeated measures latent class analysis to identify different PSU classes among PWUO. Multivariable generalised estimating equations models weighted by the respective posterior membership probabilities were applied to identify covariates of membership in different PSU classes over time.

RESULTS

Overall, 2627 PWUO (median age at baseline: 36 [quartile 1-3: 25-45]) were included between 2005 and 2018. We found five distinct PSU patterns, including low/infrequent probability of regular substance use (Class 1; 30%), primarily opioid and methamphetamine use (Class 2; 22%), primarily cannabis use (Class 3; 15%), primarily opioid and crack use (Class 4; 29%) and frequent PSU (Class 5; 4%). Membership in Class 2, 4 and 5 was positively associated with several behavioural and socio-structural adversities.

DISCUSSION AND CONCLUSIONS

Findings of this longitudinal study suggest PSU is the norm among PWUO and highlights the heterogeneous characteristics of PWUO. The diversities within the population of PWUO need to be recognised in addiction care and treatment as well as optimising resource allocation in the response to the overdose crisis.

An answered call for aid? Cannabinoid clinical framework for the opioid epidemic

BACKGROUND

The opioid crisis continues in full force, as physicians and caregivers are desperate for resources to help patients with opioid use and chronic pain disorders find safer and more accessible non-opioid tools.

MAIN BODY

The purpose of this article is to review the current state of the opioid epidemic; the shifting picture of cannabinoids; and the research, policy, and current events that make opioid risk reduction an urgent public health challenge. The provided table contains an evidence-based clinical framework for the utilization of cannabinoids to treat patients with chronic pain who are dependent on opioids, seeking alternatives to opioids, and tapering opioids.

CONCLUSION

Based on a comprehensive review of the literature and epidemiological evidence to date, cannabinoids stand to be one of the most interesting, safe, and accessible tools available to attenuate the devastation resulting from the misuse and abuse of opioid narcotics. Considering the urgency of the opioid epidemic and broadening of cannabinoid accessibility amidst absent prescribing guidelines, the authors recommend use of this clinical framework in the contexts of both clinical research continuity and patient care.

Genetics of cannabis use in opioid use disorder: A genome-wide association and polygenic risk score study

BACKGROUND

Individuals with an Opioid Use Disorder (OUD) have increased rates of cannabis use in comparison to the general population. Research on the short- and long-term impacts of cannabis use in OUD patients has been inconclusive. A genetic component may contribute to cannabis cravings.

AIMS

Identify genetic variants associated with cannabis use through Genome-wide Association Study (GWAS) methods and investigate a Polygenic Risk Score (PRS). In addition, we aim to identify any sex differences in effect size for genetic variants reaching or nearing genome-wide significance in the GWAS.

METHODS

The study outcomes of interest were: regular cannabis use (yes/no) (n = 2616), heaviness of cannabis use (n = 1293) and cannabis cravings (n = 836). Logistic and linear regressions were preformed, respectively, to test the association between genetic variants and each outcome, regular cannabis use and heaviness of cannabis use. GWAS summary statistics from a recent large meta-GWAS investigating cannabis use disorder were used to conduct PRS's. Findings are limited to a European ancestry sample.

RESULTS

No genome-wide significant associations were found. Rs1813412 (chromosome 17) for regular cannabis use and rs62378502 (chromosome 5) for heaviness of cannabis use were approaching genome-wide significance. Both these SNPs were nominally significant (p<0.05) within males and females, however sex did not modify the association. The PRS identified statistically significant association with cannabis cravings. The variance explained by all PRSs were less than 1.02x10-2.

CONCLUSION

This study provides promising results in understanding the genetic contribution to cannabis use in individuals living with OUD.

Differential effect of cannabis use on opioid agonist treatment outcomes: Exploratory analyses from the OPTIMA study

INTRODUCTION

Conflictual evidence exists regarding the effects of cannabis use on the outcomes of opioid agonist therapy (OAT). In this exploratory analysis, we examined the effect of recent cannabis use on opioid use, craving, and withdrawal symptoms, in individuals participating in a trial comparing flexible buprenorphine/naloxone (BUP/NX) take-home dosing model to witnessed ingestion of methadone.

METHODS

We analyzed data from a multi-centric, pragmatic, 24-week, open label, randomized controlled trial in individuals with prescription-type opioid use disorder (n = 272), randomly assigned to BUP/NX (n = 138) or methadone (n = 134). The study measured last week cannabis and opioid use via timeline-follow back, recorded at baseline and every two weeks during the study. Craving symptoms were measured using the Brief Substance Craving Scale at baseline, and weeks 2, 6, 10, 14, 18 and 22. The study measured opioid withdrawal symptoms via Clinical Opiate Withdrawal Scale at treatment initiation and weeks 2, 4, and 6.

RESULTS

The mean maximum dose taken during the study was 17.3 mg/day (range = 0.5-32 mg/day) for BUP/NX group and 67.7 mg/day (range = 10-170 mg/day) in the methadone group. Repeated measures generalized linear mixed models demonstrated that cannabis use in the last week (mean of 2.3 days) was not significantly associated with last week opioid use (aβ ± standard error (SE) = -0.06 ± 0.04; p = 0.15), craving (aβ ± SE = -0.05 ± 0.08, p = 0.49), or withdrawal symptoms (aβ ± SE = 0.09 ± 0.1, p = 0.36). Bayes factor (BF) for each of the tested models supported the null hypothesis (BF < 0.3).

CONCLUSIONS

The current study did not demonstrate a statistically significant effect of cannabis use on outcomes of interest in the context of a pragmatic randomized-controlled trial. These findings replicated previous results reporting no effect of cannabis use on opioid-related outcomes.

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.

Polysubstance use before and during treatment with medication for opioid use disorder: Prevalence and association with treatment outcomes

OBJECTIVE

Polysubstance use may complicate treatment outcomes for individuals who use opioids. This research aimed to examine the prevalence of polysubstance use in an opioid use disorder treatment trial population and polysubstance use's association with opioid relapse and craving.

METHODS

This study is a secondary data analysis of individuals with opioid use disorder who received at least one dose of medication (n = 474) as part of a 24-week, multi-site, open label, randomized Clinical Trials Network study (CTN0051, X:BOT) comparing the effectiveness of extended-release naltrexone versus buprenorphine. Models examined pretreatment polysubstance use and polysubstance use during the initial 4 weeks of treatment on outcomes of relapse by week 24 of the treatment trial and opioid craving.

RESULTS

Polysubstance use was generally not associated with treatment outcomes of opioid relapse and craving. Proportion of days of pretreatment sedative use was associated with increased likelihood of opioid relapse (OR: 1.01, 95 % CI: 1.00-1.02). Proportion of days of cocaine use during the initial 4 weeks of treatment was associated with increased likelihood of opioid relapse (OR: 1.05, 95 % CI: 1.01-1.09) but this effect was no longer significant once the potential of confounding by opioid use was considered. Sedative use during initial 4 weeks of treatment was associated with increased opioid craving (b: 0.77, 95 % CI: 0.01-1.52). The study found no other significant relationships.

CONCLUSIONS

In the current study population, polysubstance use was only marginally associated with 24-week treatment outcomes.

Multimodal MRI data fusion reveals distinct structural, functional and neurochemical correlates of heavy cannabis use

Heavy cannabis use (HCU) is frequently associated with a plethora of cognitive, psychopathological and sensorimotor phenomena. Although HCU is frequent, specific patterns of abnormal brain structure and function underlying HCU in individuals presenting without cannabis-use disorder or other current and life-time major mental disorders are unclear at present. This multimodal magnetic resonance imaging (MRI) study examined resting-state functional MRI (rs-fMRI) and structural MRI (sMRI) data from 24 persons with HCU and 16 controls. Parallel independent component analysis (p-ICA) was used to examine covarying components among grey matter volume (GMV) maps computed from sMRI and intrinsic neural activity (INA), as derived from amplitude of low-frequency fluctuations (ALFF) maps computed from rs-fMRI data. Further, we used JuSpace toolbox for cross-modal correlations between MRI-based modalities with nuclear imaging derived estimates, to examine specific neurotransmitter system changes underlying HCU. We identified two transmodal components, which significantly differed between the HCU and controls (GMV: p = 0.01, ALFF p = 0.03, respectively). The GMV component comprised predominantly cerebello-temporo-thalamic regions, whereas the INA component included fronto-parietal regions. Across HCU, loading parameters of both components were significantly associated with distinct HCU behavior. Finally, significant associations between GMV and the serotonergic system as well as between INA and the serotonergic, dopaminergic and μ-opioid receptor system were detected. This study provides novel multimodal neuromechanistic insights into HCU suggesting co-altered structure/function-interactions in neural systems subserving cognitive and sensorimotor functions.

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.

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.