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

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.

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.

Outcomes from the medication assisted treatment pilot program for adults with opioid use disorders in rural Colorado

BACKGROUND

As Colorado ranked among the top nationally in non-medical use of opioids, a pilot medication for opioid use disorder (MOUD) program was developed to increase the number of NPs and PAs providing MOUD in order to bring this evidence- based treatment to 2 counties showing disproportionally high opioid overdose deaths. Over the first 18 months, the MOUD Pilot Program led to 15 new health care providers receiving MOUD waiver training and 1005 patients receiving MOUD from the 3 participating organizations. Here we evaluate patient centered clinical and functional outcomes of the pilot MOUD program implemented in 2 rural counties severely affected by the opioid crisis.

METHODS

Under state-funded law (Colorado Senate Bill 17-074), three rural agencies submitted de-identified patient-level data at baseline (N = 1005) and after 6 months of treatment (N = 190, 25%) between December 2017 and January 2020. The Addiction Severity Index, PhQ9 and GAD-7 with McNemar-Bowker, and Wilcoxon Signed Rank tests analysis were used to measure patient outcomes across after participation in the program. .

RESULTS

Patients in treatment reported using less heroin (52.1% vs 20.4%), opioids (22.3% vs 11.0%), and alcohol (28.6% vs 13.1%, all P < 0.01). Patients reported improved health (53.4% vs. 68.2%, P = 0.04), less frequency of disability (8.69 vs. 6.51, P = 0.02), symptoms (29.8% vs 21.3%), pain (67.5% to 53.6), worry (45.3% vs 62.3%), anxiety (49.7% vs 23.2%), depression (54.1% vs 23.3%, all P < 0.02) after treatment.

CONCLUSIONS

This study shows decreased substance use, improved physical and mental health, and reduced symptoms after 6 months of MOUD. Although more research on retention and long-term effects is needed, data shows improved health outcomes after 6 months of MOUD. Lessons learned from implementing this pilot program informed program expansion into other rural areas in need to address some of Colorado' major public health crises.

Endogenous opiates and behavior: 2019

This paper is the forty-second consecutive installment of the annual anthological review of research concerning the endogenous opioid system, summarizing articles published during 2019 that studied the behavioral effects of molecular, pharmacological and genetic manipulation of opioid peptides and receptors as well as effects of opioid/opiate agonists and antagonists. The review is subdivided into the following specific topics: molecular-biochemical effects and neurochemical localization studies of endogenous opioids and their receptors (1), the roles of these opioid peptides and receptors in pain and analgesia in animals (2) and humans (3), opioid-sensitive and opioid-insensitive effects of nonopioid analgesics (4), opioid peptide and receptor involvement in tolerance and dependence (5), stress and social status (6), learning and memory (7), eating and drinking (8), drug abuse and alcohol (9), sexual activity and hormones, pregnancy, development and endocrinology (10), mental illness and mood (11), seizures and neurologic disorders (12), electrical-related activity and neurophysiology (13), general activity and locomotion (14), gastrointestinal, renal and hepatic functions (15), cardiovascular responses (16), respiration and thermoregulation (17), and immunological responses (18).

Trend differences over 20 years between two methadone maintenance clinics, one with and one without cannabis legalization

BACKGROUND

Although methadone maintenance treatment (MMT) guidelines are well established, patients' characteristics and outcome change over time may be affected by the legality of cannabis.

OBJECTIVE

To study trend changes between two clinics over 20 years from Las Vegas (LV) and 27 years from Tel Aviv (TA).

METHODS

Patients' characteristics at admission, including drugs in urine at first and 13th month were obtained from their medical charts. Changes by year of admission and cumulative retention were analyzed.

RESULTS

The LV MMT clinic (1724 patients) had a lower one-year retention rate compared to the TA MMT clinic (1014 patients) (46.4% vs. 74.4%, respectively, p < 0.0005), and a higher rate of opioid stop after one year (75.9% vs. 68.8%, respectively, p = 0.003). The age at MMT admission and the retention rates decreased in LV and increased in TA. The prevalence of cannabis and benzodiazepine misuse on MMT admission increased in LV with no change recorded in TA. Cocaine on MMT admission decreased in LV and increased in TA, while amphetamine use increased in LV and decreased in TA. Cox models multivariate analyses found cannabis on admission to predict shorter retention in LV (as younger age male and amphetamines), and cannabis after one year in TA (as did cocaine and opiates after one year and BDZ on admission).

CONCLUSION

Although cannabis prevalence increased only in LV where it was legalized, it was associated with poor outcomes in both clinics. Younger age, a known poor outcome predictor, may be related to decreased retention in LV.

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.