Opioid-Sparing Effect of Cannabinoids: A Systematic Review and Meta-Analysis

Association between history of cannabis use and outcomes after total hip or knee arthroplasty: a systematic review and meta-analysis

Background

Cannabis use may be increasing as countries legalize it and it becomes socially acceptable. A history of cannabis use may increase risk of complications after various kinds of surgery and compromise functional recovery. Here we systematically reviewed and meta-analyzed available evidence on how history of cannabis use affects recovery after hip or knee arthroplasty (THA/TKA).

Methods

The PubMed, EMBASE, and Web of Science databases were comprehensively searched and studies were selected and analyzed in accordance with the PRISMA guidelines. The methodological quality of included studies was assessed based on the Newcastle-Ottawa Scale, while quality of evidence was evaluated according to the "Grading of recommendations assessment, development, and evaluation" system. Data on various outcomes were pooled when appropriate and meta-analyzed.

Results

The systematic review included 16 cohort studies involving 5.91 million patients. Meta-analysis linked history of cannabis use to higher risk of the following outcomes: revision (RR 1.68, 95% CI 1.31-2.16), mechanical loosening (RR 1.77, 95% CI 1.52-2.07), periprosthetic fracture (RR 1.85, 95% CI 1.38-2.48), dislocation (RR 2.10, 95% CI 1.18-3.73), cardiovascular events (RR 2.49, 95% CI 1.22-5.08), cerebrovascular events (RR 3.15, 95% CI 2.54-3.91), pneumonia (RR 3.97, 95% CI 3.49-4.51), respiratory failure (RR 4.10, 95% CI 3.38-4.97), urinary tract infection (RR 2.46, 95% CI 1.84-3.28), acute kidney injury (RR 3.25, 95% CI 2.94-3.60), venous thromboembolism (RR 1.48, 95% CI 1.34-1.63), and deep vein thrombosis (RR 1.42, 95% CI 1.19-1.70). In addition, cannabis use was associated with significantly greater risk of postoperative transfusion (RR 2.23, 95% CI 1.83-2.71) as well as higher hospitalization costs.

Conclusion

History of cannabis use significantly increases the risk of numerous complications and transfusion after THA or TKA, leading to greater healthcare costs. Clinicians should consider these factors when treating cannabis users, and pre-surgical protocols should give special consideration to patients with history of cannbis use.

Neural circuit basis of adolescent THC-induced potentiation of opioid responses in adult mice

Use of one drug of abuse typically influences the behavioral response to other drugs, either administered at the same time or a subsequent time point. The nature of the drugs being used, as well as the timing and dosing, also influence how these drugs interact. Here, we tested the effects of adolescent THC exposure on the development of morphine-induced behavioral adaptations following repeated morphine exposure during adulthood. We found that adolescent THC administration impacted morphine-induced behaviors across several dimensions, including potentiating reward and paradoxically impairing the development of morphine reward. We then mapped the whole-brain response to a reinstatement dose of morphine, finding that adolescent THC administration led to increased activity in the basal ganglia and increased functional connectivity between frontal cortical regions and the ventral tegmental area. Last, we show using rabies virus-based circuit mapping that adolescent THC exposure triggers a long-lasting elevation in connectivity from the frontal cortex regions onto ventral tegmental dopamine cells that has the potential to influence dopaminergic response to morphine administration during adulthood. Our study adds to the rich literature on the interaction between drugs of abuse and provides potential circuit substates by which adolescent THC exposure influences responses to morphine later in life.

Overview: Chronic Pain and Cannabis-Based Medicines

Chronic pain is primarily conceptualized as a disease in its own right when it is associated with emotional distress and functional impairment. Pathophysiologically, dysfunction of the cortico-mesolimbic connectome is of major importance, with overlapping signals in the nociceptive and stress systems. The endocannabinoid system plays an important role in the central processing of nociceptive signals and regulates the central stress response. Clinically, there is moderate evidence that cannabis-based medicines (CBM) can contribute to a significant reduction in pain, especially the associated pain affect, and improvement in physical function and sleep quality in a proportion of patients with chronic pain. The analgesic effect appears to be largely independent of the cause of pain. In this context, CBM preferentially regulates stress-associated pain processing.

Associations Between Buprenorphine\Naloxone and Methadone Treatment and non-Opioid Substance Use in Prescription-Type Opioid Use Disorder: Secondary Analyses From the OPTIMA Study: Associations entre le traitement avec la buprénorphine/naloxone et avec la méthadone et l'utilisation de substances non opioïdes dans le trouble lié à l'usage d'opioïdes de type sur ordonnance : analyses secondaires de l'étude OPTIMA

OBJECTIVES

There is limited evidence on how opioid agonist treatment (OAT) may affect psychoactive non-opioid substance use in prescription-type opioid use disorder (POUD) and whether this effect might explain OAT outcomes. We aimed to assess the effect of methadone on non-opioid substance use compared to buprenorphine/naloxone (BUP/NX), to explore whether non-opioid substance use is associated with opioid use and retention in treatment, and to test non-opioid use as a moderator of associations between methadone with retention in OAT and opioid use compared to BUP/NX.

METHODS

This is a secondary analysis of data from the OPTIMA trial, an open-label, pragmatic, parallel, two-arm, pan-Canadian, multicentre, randomized-controlled trial to compare standard methadone model of care and flexible take-home dosing BUP/NX for POUD treatment. We studied the effect of methadone and BUP/NX on non-opioid substance use evaluated by urine drug screen (UDS) and by classes of non-opioid substances (i.e., tetrahydrocannabinol [THC], benzodiazepines, stimulants) (weeks 2-24) using adjusted generalized estimation equation (GEE). We studied the association between non-opioid substance-positive UDS and opioid-positive UDS and retention in treatment, using adjusted GEE and logistic regressions.

RESULTS

Overall, methadone was not associated with non-opioid substance-positive UDS compared to BUP/NX (OR: 0.78; 95%CI, 0.41 to 1.48). When non-opioid substances were studied separately, methadone was associated with lower odds of benzodiazepine-positive UDS (OR: 0.63; 95% CI: 0.40 to 0.98) and THC-positive UDS (OR: 0.47; 95% CI: 0.28 to 0.77), but not with different odds of stimulant-positive UDS (OR: 1.29; 95% CI: 0.78 to 2.16) compared to BUP/NX. Substance-positive UDS, overall and separate classes, were not associated with opioid-positive UDS or retention in treatment.

CONCLUSION

Methadone did not show a significant effect on overall non-opioid substance use in POUD compared to BUP/NX treatment but was associated with lower odds of benzodiazepine and THC use in particular. Non-opioid substance use did not predict OAT outcomes. Further research is needed to ascertain whether specific patterns of polysubstance use (quantity and frequency) may affect treatment outcomes.

Herb-drug interactions: A short review on central and peripheral nervous system drugs

Herbal medicines are widely perceived as natural and safe remedies. However, their concomitant use with prescribed drugs is a common practice, often undertaken without full awareness of the potential risks and frequently without medical supervision. This practice introduces a tangible risk of herb-drug interactions, which can manifest as a spectrum of consequences, ranging from acute, self-limited reactions to unpredictable and potentially lethal scenarios. This review offers a comprehensive overview of herb-drug interactions, with a specific focus on medications targeting the Central and Peripheral Nervous Systems. Our work draws upon a broad range of evidence, encompassing preclinical data, animal studies, and clinical case reports. We delve into the intricate pharmacodynamics and pharmacokinetics underpinning each interaction, elucidating the mechanisms through which these interactions occur. One pressing issue that emerges from this analysis is the need for updated guidelines and sustained pharmacovigilance efforts. The topic of herb-drug interactions often escapes the attention of both consumers and healthcare professionals. To ensure patient safety and informed decision-making, it is imperative that we address this knowledge gap and establish a framework for continued monitoring and education. In conclusion, the use of herbal remedies alongside conventional medications is a practice replete with potential hazards. This review not only underscores the real and significant risks associated with herb-drug interactions but also underscores the necessity for greater awareness, research, and vigilant oversight in this often-overlooked domain of healthcare.

Natural Products Derived from Cannabis sativa for Pain Management

Cannabis sativa is one of the oldest medicinal plants in human history. Even ancient physicians from hundreds of years ago used Cannabis sativa to treat several conditions like pain. In the modern era, the research community, including health-care providers, have witnessed wide-scale changes in cannabis policy, legislation, and marketing, with a parallel increase in patient interest. A simple search in PubMed using "cannabis and pain" as keywords provides more than 2,400 articles, about 80% of which were published in the last 8-10 years. Several advancements have been achieved in understanding the complex chemistry of cannabis along with its multiple pharmacological activities. Preclinical data have demonstrated evidence for the promising potential of cannabis for pain management, and the continuous rise in the prevalence of pain increases the urgency to translate this into clinical practice. Despite the large body of cannabis literature, researchers still need to find rigorous answers for the questions about the efficacy and safety of cannabis in treatment of certain disorders such as pain. In the current chapter, we seek to present a critical overview about the current knowledge on cannabis with special emphasis on pain-related disorders.

The Effect of Preoperative Marijuana Use on Surgical Outcomes, Patient-Reported Outcomes, and Opioid Consumption Following Lumbar Fusion

STUDY DESIGN

Retrospective Cohort Study.

OBJECTIVES

To (1) investigate the effect of marijuana use on surgical outcomes following lumbar fusion, (2) determine how marijuana use affects patient-reported outcomes measures (PROMs), and (3) determine if marijuana use impacts the quantity of opioids prescribed.

METHODS

Patients > 18 years of age who underwent primary one- or two-level lumbar fusion with preoperative marijuana use at our institution were identified. A 3:1 propensity match incorporating patient demographics and procedure type was conducted to compare preoperative marijuana users to non-marijuana users. Patient demographics, surgical characteristics, surgical outcomes (90-day all-cause and 90-day surgical readmissions, reoperations, and revision surgeries), pre- and postoperative narcotic usage, and PROMs were compared between groups. Multivariate regression models were created to determine the effect of marijuana on surgical reoperations patient-reported outcomes (PROMs) 1-year postoperatively.

RESULTS

Of the 259 included patients, 65 used marijuana preoperatively. Multivariate logistic regression analysis demonstrated that marijuana use (OR = 2.28, P = .041) significantly increased the likelihood of having a spine reoperation. No other surgical outcome was found to be significantly different between groups. Multivariate linear regression analysis showed that marijuana use was not significantly associated with changes in 1-year postoperative PROMs (all, P > .05). The quantity of pre- and postoperative opioids prescriptions was not significantly different between groups (all, P > .05).

CONCLUSIONS

Preoperative marijuana use increased the likelihood of a spine reoperation for any indication following lumbar fusion, but it was not associated with 90-day all cause readmission, surgical readmission, the magnitude of improvement in PROMs, or differences in opioid consumption.

LEVEL OF EVIDENCE

III.

Tetrahydrocannabinol and Cannabidiol for Pain Treatment-An Update on the Evidence

In light of the current International Association for the Study of Pain (IASP) clinical practice guidelines (CPGs) and the European Society for Medical Oncology (ESMO) guidelines, the topic of cannabinoids in relation to pain remains controversial, with insufficient research presently available. Cannabinoids are an attractive pain management option due to their synergistic effects when administered with opioids, thereby also limiting the extent of respiratory depression. On their own, however, cannabinoids have been shown to have the potential to relieve specific subtypes of chronic pain in adults, although controversies remain. Among these subtypes are neuropathic, musculoskeletal, cancer, and geriatric pain. Another interesting feature is their effectiveness in chemotherapy-induced peripheral neuropathy (CIPN). Analgesic benefits are hypothesized to extend to HIV-associated neuropathic pain, as well as to lower back pain in the elderly. The aim of this article is to provide an up-to-date review of the existing preclinical as well as clinical studies, along with relevant systematic reviews addressing the roles of various types of cannabinoids in neuropathic pain settings. The impact of cannabinoids in chronic cancer pain and in non-cancer conditions, such as multiple sclerosis and headaches, are all discussed, as well as novel techniques of administration and relevant mechanisms of action.

Awareness and interest in cannabis use for cancer management among cancer survivors

BACKGROUND

We examined the awareness, interest, and information sources relating to cannabis use for cancer management (including management of cancer symptoms and treatment-related side effects) and determined factors associated with cancer survivors' awareness and interest in learning about cannabis use for cancer management.

METHODS

This was a cross-sectional study of adult cancer survivors (N = 1886) receiving treatment at a comprehensive cancer center. Weighted prevalence and multivariable logistic regression analyses were conducted.

RESULTS

Among cancer survivors, 88% were aware and 60% were interested in learning about cannabis use for cancer management. Common sources of information to learn about cannabis use for cancer management were cancer doctors/nurses (82%), other patients with cancer (27%), websites/blogs (26%), marijuana stores (20%), and family/friends (18%). The odds of being aware of cannabis use for cancer management was lower among male compared to female survivors (adjusted odds ratio [AOR]: 0.61; 95% confidence interval [CI]: 0.41-0.90), non-Hispanic Blacks compared to non-Hispanic Whites (AOR: 0.36; 95% CI: 0.21-0.62), and survivors who do not support the legalization of cannabis for medical use compared to those who do (AOR: 0.10; 95% CI: 0.04-0.23). On the other hand, the odds of being interested in cannabis use for cancer management was higher among non-Hispanic Blacks compared to non-Hispanic Whites (AOR: 1.65; 95% CI: 1.04-2.62), and among cancer survivors actively undergoing cancer treatment compared to patients on non-active treatment (AOR: 2.25; 95% CI: 1.74-2.91).

CONCLUSION

Awareness of cannabis use for cancer management is high within the cancer survivor population. Results indicated health care providers are leading information source and should receive continued medical education on cannabis-specific guidelines. Similarly, tailored educational interventions are needed to guide survivors on the benefits and risks of cannabis use for cancer management.

Supporting gut health with medicinal cannabis in people with advanced cancer: potential benefits and challenges

The side effects of cancer therapy continue to cause significant health and cost burden to the patient, their friends and family, and governments. A major barrier in the way in which these side effects are managed is the highly siloed mentality that results in a fragmented approach to symptom control. Increasingly, it is appreciated that many symptoms are manifestations of common underlying pathobiology, with changes in the gastrointestinal environment a key driver for many symptom sequelae. Breakdown of the mucosal barrier (mucositis) is a common and early side effect of many anti-cancer agents, known to contribute (in part) to a range of highly burdensome symptoms such as diarrhoea, nausea, vomiting, infection, malnutrition, fatigue, depression, and insomnia. Here, we outline a rationale for how, based on its already documented effects on the gastrointestinal microenvironment, medicinal cannabis could be used to control mucositis and prevent the constellation of symptoms with which it is associated. We will provide a brief update on the current state of evidence on medicinal cannabis in cancer care and outline the potential benefits (and challenges) of using medicinal cannabis during active cancer therapy.

Cannabis Use among Cancer Survivors: Use Pattern, Product Type, and Timing of Use

Despite growing interest in the use of cannabis for the treatment of cancer-related symptoms, there are limited studies that have assessed the use pattern, type, and mode of delivery of cannabis products used by cancer survivors. This study describes the current state of the use pattern, product type, and mode of delivery of cannabis used by cancer survivors. This was a cross-sectional study of cancer survivors from 41 U.S. states who received treatment at the largest NCI-designated comprehensive cancer center. The weighted prevalence of the use patterns, product types, and modes of delivery of cannabis used by cancer survivors was estimated. A total of 1886 cancer survivors were included in the study, with 915 (48% [95% CI: 45-51]) reporting ever using cannabis. Of survivors who had ever used cannabis, 36% (95% CI: 33-40) were current users. Among survivors who reported cannabis use after diagnosis, 40% used cannabis during and after cancer treatment, 35% used cannabis during treatment, and 25% used cannabis after completing their cancer treatment. Additionally, 48% of survivors reported an increase in cannabis use since cancer diagnosis. The commonest types of cannabis products used by cancer survivors were dry leaf cannabis (71%), cannabidiol (CBD) oil (46%), and cannabis candy (40%). Moreover, cancer survivors frequently used baked goods (32%), creams and gels (21%), and tinctures (18%). Furthermore, among ever users, the predominant mode of use was cannabis inhalation/smoking (69%) compared to eating/drinking (59%). More so, the common mode of inhalation/smoking of cannabis products were rolled cannabis cigarettes (79%), pipes (36%), water pipes (34%), vaporizers or vapes (14%), and e-cigarette devices (14%). A substantial number of cancer survivors use cannabis during cancer treatment, with increased use following cancer diagnosis. The forms and modes of delivery of cannabis varied among survivors, with most survivors inhaling or smoking cannabis. There is a need to educate healthcare providers (HCPs) and survivors on current evidence of cannabis use and strengthen cannabis regulatory frameworks to optimize benefits and minimize adverse events from cannabis use during cancer treatment.

Drug Interactions of Tetrahydrocannabinol and Cannabidiol in Cannabinoid Drugs

BACKGROUND

Cannabinoid drugs containing tetrahydrocannabinol (THC), or its structural analogues, as monotherapeutic agents or as extracts or botanical preparations with or without cannabidiol (CBD) are often prescribed to multimorbid patients who are taking multiple drugs. This raises the question of the risk of drug interactions.

METHODS

This review of the pharmacokinetics and pharmacodynamics of interactions with cannabinoid drugs and their potential effects is based on pertinent publications retrieved by a selective literature search.

RESULTS

As THC and CBD are largely metabolized in the liver, their bioavailability after oral or oral-mucosal administration is low (6-8% and 11-13%, respectively). The plasma concentrations of THC and its active metabolite 11-OH-THC can be increased by strong CYP3A4 inhibitors (verapamil, clarithromycin) and decreased by strong CYP3A4 inductors (rifampicin, carbamazepine). The clinical significance of these effects is unclear because of the variable plasma level and therapeutic spectrum of THC. The metabolism of CBD is less dependent on cytochrome P450 enzymes than that of THC. THC and CBD inhibit CYP2C and CYP3A4; the corresponding clinically relevant drug interactions probably are likely to arise only with THC doses above 30 mg/day and CBD doses above 300 mg/day.

CONCLUSION

Potential drug interactions with THC and CBD are probably of little importance at low or moderate doses. Strong CYP inhibitors or inductors can intensify or weaken their effect. Slowly ramping up the dose of oral cannabinoid drugs can lessen their pharmacodynamic interactions, which can generally be well controlled. Administration by inhalation can worsen the interactions.

Opioid and healthcare service use in medical cannabis patients with chronic pain: a prospective study

BACKGROUND

Various jurisdictions have legalised medical cannabis (MC) for use in chronic pain treatment. The objective of this study was to determine if the use of MC is related to a reduction in the use of prescription opioids and other prescription medications and healthcare services.

METHODS

A retrospective cohort study was conducted using the medical files of 68 Israeli patients with chronic pain using MC. Number of prescription medications filled and healthcare services used were recorded separately for the baseline period (6 months prior to the start of MC treatment) and 6 months' follow-up. Paired t-tests were used to compare each individual to himself/herself from baseline to follow-up.

RESULTS

Patients filled less opioid prescription medication at follow-up compared with baseline, and the reduction was of small effect size. There were no significant changes in the use of other medications or use of healthcare services from pre-MC treatment to follow-up.

CONCLUSIONS

MC may be related to a significant yet small reduction in opioid prescription medication. Further prospective studies with representative samples are warranted to confirm the potential small opioid-sparing effects of MC treatment, its clinical importance, if any, and potential lack of association with other healthcare-related services and medication use. Due to methodological limitations of the data used in this study, results may be regarded as preliminary and causal inferences cannot be made.

Patient-targeted interventions for opioid deprescribing: An overview of systematic reviews

BACKGROUND

Deprescribing (reduction or cessation) of prescribed opioids can be challenging for both patients and healthcare professionals.

OBJECTIVE

To synthesize and evaluate evidence from systematic reviews examining the effectiveness and outcomes of patient-targeted opioid deprescribing interventions for all types of pain.

METHODS

Systematic searches were conducted in five databases with results screened against predetermined inclusion/exclusion criteria. Primary outcomes were (i) reduction in opioid dose, reported as change in oral Morphine Equivalent Daily Dose (oMEDD) and (ii) success of opioid deprescribing, reported as the proportion of the sample for which opioid use declined. Secondary outcomes included pain severity, physical function, quality of life and adverse events. The certainty of evidence was assessed using Grading of Recommendations Assessment, Development and Evaluation (GRADE) methodology.

FINDINGS

Twelve reviews were eligible for inclusion. Interventions were heterogeneous in nature and included pharmacological (n = 4), physical (n = 3), procedural (n = 3), psychological or behavioural (n = 3) and mixed (n = 5) interventions. Multidisciplinary care programmes appeared to be the most effective intervention for opioid deprescribing; however, the certainty of evidence was low, with significant variability in opioid reduction across interventions.

CONCLUSIONS

Evidence is too uncertain to draw firm conclusions about specific populations who may derive the greatest benefit from opioid deprescribing, warranting further investigation.

Medicinal use of cannabis: A qualitative study of the perspectives of doctors and pharmacists from six African countries

We conducted a qualitative study to examine the enablers and barriers influencing the implementation of medical cannabis from the perspectives of practicing doctors and pharmacists within the African context. Interviews were conducted to investigate medical professionals' perceptions and concerns regarding medicinal cannabis. Three major themes were identified: beliefs about consequences, optimism, and environmental resources and context. Depending on the context of use, medical professionals described cannabis as potentially useful as an adjunct medicine and yet problematic owing to knowledge and social barriers, particularly religion. Implementation strategies tailored to address structural and social concerns to providing optimal care are needed to ensure that medical professionals are well versed in policy and clinical aspects.

Within-subject, double-blind, randomized, placebo-controlled evaluation of combining the cannabinoid dronabinol and the opioid hydromorphone in adults with chronic pain

The potential synergistic effects of combining cannabinoids and opioids for analgesia has received considerable attention. No studies to date have evaluated this combination in patients with chronic pain. The present study aimed to evaluate the combined analgesic and drug effects of oral opioid (hydromorphone) and delta-9-tetrahydrocannabinol (dronabinol), as well as their effects on physical and cognitive functioning, and human abuse potential (HAP) outcomes among individuals with knee osteoarthritis (KOA). This was a within-subject, double-blind, randomized, placebo-controlled study. Participants (N = 37; 65% women; mean age = 62) diagnosed with knee osteoarthritis of ≥3/10 average pain intensity were included. Participants received (1) placebo-placebo, (2) hydromorphone (4 mg)-placebo; (3) dronabinol (10 mg)-placebo, and (4) hydromorphone (4 mg)-dronabinol (10 mg). Clinical and experimentally-induced pain, physical and cognitive function, subjective drug effects, HAP, adverse events, and pharmacokinetics were evaluated. No significant analgesic effects were observed for clinical pain severity or physical functioning across all drug conditions. Little enhancement of hydromorphone analgesia by dronabinol was observed on evoked pain indices. While subjective drug effects and some HAP ratings were increased in the combined drug condition, these were not significantly increased over the dronabinol alone condition. No serious adverse events were reported; hydromorphone produced more mild adverse events than placebo, but hydromorphone + dronabinol produced more moderate adverse events than both placebo and hydromorphone alone. Only hydromorphone impaired cognitive performance. Consistent with laboratory studies on healthy adults, the present study shows minimal benefit of combining dronabinol (10 mg) and hydromorphone (4 mg) for analgesia and improving physical functioning in adults with KOA.

Effect of Preoperative Marijuana on Patient Outcomes and Opioid Use after Lumbar Decompression

STUDY DESIGN

Retrospective Cohort Study.

OBJECTIVES

Our study aims to analyze the effect of preoperative marijuana use on outcomes and postoperative opioid use in patients who have undergone lumbar decompression without fusion.

METHODS

All patients >18 years of age who underwent lumbar decompression from 2017-2022 with documented preoperative marijuana use at our academic institution were retrospectively identified. A 3:1 propensity match incorporating demographics, procedure type, and levels decompressed was performed to compare preoperative marijuana users and non-users. 1-year preoperative and postoperative opioid consumption in milligrams of morphine equivalents and postoperative outcomes including readmissions, reoperations, and complications, were obtained. A multivariate regression model was performed to measure the effect of marijuana use on the likelihood of a spine reoperation.

RESULTS

Of the 340 included patients, 85 were preoperative marijuana users. There were no significant differences in medical complications, 90-day readmissions, or opioid consumption preoperatively or postoperatively (P > .05). We identified a trend towards patients who used marijuana having more reoperations for any cause (20.0% vs 11.37%, P = .067). Multivariate logistic regression analysis suggested that preoperative marijuana use was a significant predictor of all-spine reoperations (OR = 2.06, P = .036).

CONCLUSIONS

In lumbar decompression patients, preoperative marijuana use does not impact opioid consumption, readmissions, or medical complications, but is a significant predictor of future postoperative reoperations. Additional research is necessary to further explore the role of marijuana use in spine surgery.

Delta-9-tetrahydrocannabinol modulates pain sensitivity among persons receiving opioid agonist therapy for opioid use disorder: A within-subject, randomized, placebo-controlled laboratory study

The opioid and cannabinoid receptor systems are inextricably linked-overlapping at the anatomical, functional and behavioural levels. Preclinical studies have reported that cannabinoid and opioid agonists produce synergistic antinociceptive effects. Still, there are no experimental data on the effects of cannabinoid agonists among humans who receive opioid agonist therapies for opioid use disorder (OUD). We conducted an experimental study to investigate the acute effects of the delta-9-tetrahydrocannabinol (THC) among persons receiving methadone therapy for OUD. Using a within-subject, crossover, human laboratory design, 25 persons on methadone therapy for OUD (24% women) were randomly assigned to receive single oral doses of THC (10 or 20 mg, administered as dronabinol) or placebo, during three separate 5-h test sessions. Measures of experimental and self-reported pain sensitivity, abuse potential, cognitive performance and physiological effects were collected. Mixed-effects models examined the main effects of THC dose and interactions between THC (10 and 20 mg) and methadone doses (low-dose methadone defined as <90 mg/day; high dose defined as >90 mg/day). Results demonstrated that, for self-reported rather than experimental pain sensitivity measures, 10 mg THC provided greater relief than 20 mg THC, with no substantial evidence of abuse potential, and inconsistent dose-dependent cognitive adverse effects. There was no indication of any interaction between THC and methadone doses. Collectively, these results provide valuable insights for future studies aiming to evaluate the risk-benefit profile of cannabinoids to relieve pain among individuals receiving opioid agonist therapy for OUD, a timely endeavour amidst the opioid crisis.

The association between cannabis use and risk of non-medical pain reliever misuse onset among young adults in a legal cannabis context

BACKGROUND

Little is known about the prospective relationship between cannabis use and pain reliever misuse. This study examined associations of non-medical and medical cannabis use with onset of non-medical pain reliever misuse among young adults in Washington State (WA), where non-medical cannabis is legal.

METHODS

Data were from a cohort-sequential study of adults 18-25 residing in WA. Four annual surveys were used from cohorts recruited in 2014, 2015, and 2016. Participants who had not reported non-medical pain reliever misuse at baseline were included in discrete time survival analyses (N = 4,236). Odds ratios (ORs) were estimated for new onset of non-medical pain reliever misuse in any given follow-up year over the course of three years according to baseline non-medical and medical cannabis use.

RESULTS

When included separately in models, non-medical and medical cannabis use at baseline were associated with increased risk of non-medical pain reliever misuse adjusting for demographic characteristics as well as past year cigarette use and alcohol use (non-medical OR = 5.27; 95 % CI: 3.28, 8.48; medical OR = 2.21; 95 % CI: 1.39, 3.52). Including both forms of use in the model, associations of non-medical and medical cannabis use with non-medical pain reliever misuse onset remained (non-medical OR = 4.64; 95 % CI: 2.88, 7.49; medical OR = 1.65; 95 % CI: 1.04, 2.62).

CONCLUSIONS

Despite claims that cannabis use may reduce opioid use and related harms, findings suggest that cannabis use, including medical use, may not be protective, but instead may increase risk for non-medical pain reliever misuse.

Developing non-opioid therapeutics to alleviate pain among persons with opioid use disorder: a review of the human evidence

The opioid crisis remains a major public health concern, causing significant morbidity and mortality worldwide. Pain is frequently observed among individuals with opioid use disorder (OUD), and the current opioid agonist therapies (OAT) have limited efficacy in addressing the pain needs of this population. We reviewed the most promising non-opioid analgesic therapies for opioid-dependent individuals synthesising data from randomised controlled trials in the Medline database from December 2022 to March 2023. Ketamine, gabapentin, serotoninergic antidepressants, and GABAergic drugs were found to be the most extensively studied non-opioid analgesics with positive results. Additionally, we explored the potential of cannabinoids, glial activation inhibitors, psychedelics, cholecystokinin antagonists, alpha-2 adrenergic agonists, and cholinergic drugs. Methodological improvements are required to advance the development of novel analgesic strategies and establish their safety profile for opioid-dependent populations. We highlight the need for greater integration of experimental pain methods and abuse liability assessments, more granular assessments of prior opioid exposure, greater uniformity of pain types within study samples, and a particular focus on individuals with OUD receiving OAT. Finally, future research should investigate pharmacokinetic interactions between OAT and various non-opioid analgesics and perform reverse translation basic experiments, particularly with methadone and buprenorphine, which remain the standard OUD treatment.

Is Cannabis Effective in the Treatment of Chronic Back Pain?

Cannabis is commonly recognized as a recreational substance. It has been explored for its potential therapeutic applications in addressing various conditions, such as depression, anxiety, sleep disorders, neurological disorders, and chronic low back pain, which affect a significant portion of the population. In the United Kingdom, cannabis has been recognized and licensed for medical use since November 2018, with about 12 National Health Service prescriptions in circulation largely due to patient pressure, with support from media campaigns for its use when there was growing evidence of its use in intractable epilepsy. Cannabis is beginning to gain traction as an alternative or even a complementary drug to opiates with some pre-clinical studies showing opiate-sparing effects. Despite references to its therapeutic use, cannabis as a therapeutic drug has been controversial due to the negative perception of its use as a recreational drug. As a result, there have been challenges in changing the perception of healthcare authorities and clinicians on the use of cannabis as a therapeutic tool for pain relief. The stigma associated with cannabis could be responsible for the paucity of randomized controlled trials on the efficacy of medical cannabis, further decreasing the credibility of the few trials conducted.

Clinical practice guideline for deprescribing opioid analgesics: summary of recommendations

INTRODUCTION

Long term opioids are commonly prescribed to manage pain. Dose reduction or discontinuation (deprescribing) can be challenging, even when the potential harms of continuation outweigh the perceived benefits. The Evidence-based clinical practice guideline for deprescribing opioid analgesics was developed using robust guideline development processes and Grading of Recommendations, Assessment, Development and Evaluation (GRADE) methodology, and contains deprescribing recommendations for adults prescribed opioids for pain.

MAIN RECOMMENDATIONS

Eleven recommendations provide advice about when, how and for whom opioid deprescribing should be considered, while noting the need to consider each person's goals, values and preferences. The recommendations aim to achieve: implementation of a deprescribing plan at the point of opioid initiation; initiation of opioid deprescribing for persons with chronic non-cancer or chronic cancer-survivor pain if there is a lack of overall and clinically meaningful improvement in function, quality of life or pain, a lack of progress towards meeting agreed therapeutic goals, or the person is experiencing serious or intolerable opioid-related adverse effects; gradual and individualised deprescribing, with regular monitoring and review; consideration of opioid deprescribing for individuals at high risk of opioid-related harms; avoidance of opioid deprescribing for persons nearing the end of life unless clinically indicated; avoidance of opioid deprescribing for persons with a severe opioid use disorder, with the initiation of evidence-based care, such as medication-assisted treatment of opioid use disorder; and use of evidence-based co-interventions to facilitate deprescribing, including interdisciplinary, multidisciplinary or multimodal care.

CHANGES IN MANAGEMENT AS A RESULT OF THESE GUIDELINES

To our knowledge, these are the first evidence-based guidelines for opioid deprescribing. The recommendations intend to facilitate safe and effective deprescribing to improve the quality of care for persons taking opioids for pain.

Should oncologists trust cannabinoids?

Cannabis enjoyed a "golden age" as a medicinal product in the late 19th, early 20th century, but the increased risk of overdose and abuse led to its criminalization. However, the 21st century have witnessed a resurgence of interest and a large body of literature regarding the benefits of cannabinoids have emerged. As legalization and decriminalization have spread around the world, cancer patients are increasingly interested in the potential utility of cannabinoids. Although eager to discuss cannabis use with their oncologist, patients often find them to be reluctant, mainly because clinicians are still not convinced by the existing evidence-based data to guide their treatment plans. Physicians should prescribe cannabis only if a careful explanation can be provided and follow up response evaluation ensured, making it mandatory for them to be up to date with the positive and also negative aspects of the cannabis in the case of cancer patients. Consequently, this article aims to bring some clarifications to clinicians regarding the sometimes-confusing various nomenclature under which this plant is mentioned, current legislation and the existing evidence (both preclinical and clinical) for the utility of cannabinoids in cancer patients, for either palliation of the associated symptoms or even the potential antitumor effects that cannabinoids may have.

Why a distinct medical stream is necessary to support patients using cannabis for medical purposes

BACKGROUND

Since 2001, Canadians have been able to obtain cannabis for medical purposes, initially through the Access to Cannabis for Medical Purposes Regulations (ACMPR). The Cannabis Act (Bill C-45) came into force on October 17, 2018, replacing the ACMPR. The Cannabis Act enables Canadians to possess cannabis purchased from a licensed retailer without authorization for either medical or nonmedical purposes. The Cannabis Act is currently the guiding legislation which governs both medical and nonmedical access. The Cannabis Act contains some improvements for patients but is essentially the same as its previous legislation. Beginning in October 2022, the federal government is conducting a review of the Cannabis Act and is questioning whether a distinct medical cannabis stream is still required, given the ease of access to cannabis and cannabis products. Although there is overlap in the reasons for medical and recreational cannabis use, the distinct legislation of medical versus recreational use of cannabis in Canada may be under threat.

MAIN BODY

A large segment of the medical, academic, research, and lay communities agree that there is a need for distinct medical and recreational cannabis streams. Perhaps most importantly, separation of these streams is necessary to ensure that both medical cannabis patients and healthcare providers receive the required support needed to optimize benefits while minimizing risks associated with medical cannabis use. Preservation of distinct medical and recreational streams can help to ensure that needs of different stakeholders are met. For example, patients require guidance in the form of assessing the appropriateness of cannabis use, selection of appropriate products and dosage forms, dosing titration, screening for drug interactions, and safety monitoring. Healthcare providers require access to undergraduate and continuing health education as well as support from their professional organizations to ensure medical cannabis is appropriately prescribed. Although there are challenges in conducing research, as motives for cannabis use frequently straddle boundaries between medical versus recreational cannabis use, maintenance of a distinct medical stream is also necessary to ensure adequate supply of cannabis products appropriate for medical use, to reduce stigma associated with cannabis in both patients and providers, to help enable reimbursement for patients, to facilitate removal of taxation on cannabis used for medical purposes, and to promote research on all aspects of medical cannabis.

CONCLUSION

Cannabis products for medical and recreational purposes have different objectives and needs, requiring different methods of distribution, access, and monitoring. HCPs, patients, and the commercial cannabis industry would serve Canadians well to continue to advocate to policy makers to ensure the continued existence of two distinct streams and must strive to make ongoing improvements to the current programs.

Using Medical Cannabis for Chronic Pain: A Social-Ecological Framework

Early studies suggest medical cannabis (MC) has the potential to benefit people who suffer from chronic pain by offering a less addictive alternative to opioids; however, most investigators agree more research is indicated. Today, in 2023, cannabis remains a Schedule I drug and is an illegal substance in the United States under the Controlled Substances Act of 1970. Despite this designation, as of February 2022, 37 states, three territories, and the District of Columbia allowed using cannabis products to treat certain painful medical conditions. The contradictory status of federal and state legislation regarding cannabis use has resulted in delays and restrictions on relevant research. As a result, an inadequate foundation of knowledge exists needed to inform policy, program, and practice decisions concerning MC to treat pain. Implementing and controlling access to MC is influenced by overlapping individual, interpersonal, community, and organizational influences that all fall under the umbrella of federal and state policies. Increasingly, the legalization and expanded access to MC necessitates the integration of evidence, policy, and social-ecological reality. To adequately delineate these complex factors to anticipate and plan future interventions at multiple levels, we propose a social-ecological framework (SEF) for using MC to treat pain. This SEF assumes the transactional relationship between the individual and the environment and that no single factor can predict behavior or health outcomes. Our framework illustrates five dynamic levels of analysis that interact between dimensions. Key elements and intersections are discussed at the intrapersonal, interpersonal, institutional, community, and policy levels.

Alternative pain management via endocannabinoids in the time of the opioid epidemic: Peripheral neuromodulation and pharmacological interventions

The use of opioids in pain management is hampered by the emergence of analgesic tolerance, which leads to increased dosing and side effects, both of which have contributed to the opioid epidemic. One promising potential approach to limit opioid analgesic tolerance is activating the endocannabinoid system in the CNS, via activation of CB1 receptors in the descending pain inhibitory pathway. In this review, we first discuss preclinical and clinical evidence revealing the potential of pharmacological activation of CB1 receptors in modulating opioid tolerance, including activation by phytocannabinoids, synthetic CB1 receptor agonists, endocannabinoid degradation enzyme inhibitors, and recently discovered positive allosteric modulators of CB1 receptors. On the other hand, as non-pharmacological pain relief is advocated by the US-NIH to combat the opioid epidemic, we also discuss contributions of peripheral neuromodulation, involving the electrostimulation of peripheral nerves, in addressing chronic pain and opioid tolerance. The involvement of supraspinal endocannabinoid systems in peripheral neuromodulation-induced analgesia is also discussed. LINKED ARTICLES: This article is part of a themed issue on Advances in Opioid Pharmacology at the Time of the Opioid Epidemic. To view the other articles in this section visit http://onlinelibrary.wiley.com/doi/10.1111/bph.v180.7/issuetoc.

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 Opioid-Sparing Effect of Acupuncture After Abdominal Surgery: A Systematic Review and Meta-Analysis Protocol

Purpose

Routine overprescribing of postoperative opioid analgesics may induce side effects and correlate with chronic opioid use following surgery. This review aims to evaluate the effectiveness and safety of acupuncture for opioid-sparing effects in patients who underwent abdominal surgery.

Methods

Eleven databases in different languages, including English (Ovid MEDLINE, CENTRAL, EMBASE, CINAHL), Chinese, Korean, and Japanese, will be searched. Randomized controlled trials using acupuncture for postoperative pain control in adult patients undergoing abdominal surgery will be screened. All randomized controlled trials comparing acupuncture with no treatment, sham acupuncture, and conventional treatments will be included. The Cochrane risk of bias tool will be used to assess the risk of bias. The primary outcome will consist of a cumulative opioid consumption. Additionally, the number of cumulative opioid analgesic demands/requests, the time to initial opioid analgesic usage, postoperative pain, opioid-related side effects, and adverse events of acupuncture will be assessed. The mean differences or risk ratios with a 95% confidence interval will be calculated to estimate the pooled effect of acupuncture when it is possible to conduct a meta-analysis.

Results

This study could confirm the effect of opioid-sparing on acupuncture after abdominal surgery.

Conclusion

This study would evaluate the evidence on the effectiveness of acupuncture after abdominal surgery with a focus on opioid intake. It provides evidence to support decision-making on applying acupuncture for postoperative management.

Registration Number

CRD42022311155.

Medical Cannabis in Hand Surgery: A Review of the Current Evidence

Acute and chronic pain management remains an ongoing challenge for hand surgeons. This has been compounded by the ongoing opioid epidemic in the United States. With the increasing legalization of medical and recreational cannabis throughout the United States and other countries, previous societal stigmas about this substance keep evolving, and recognition of medical cannabis as an opioid-sparing pain management alternative is growing. A review of the current literature demonstrates a strong interest from patients regarding the use of medical cannabis for pain control. Current evidence demonstrates its efficacy and safety for chronic musculoskeletal and neuropathic pain. However, definitive conclusions regarding the efficacy of cannabis for pain control in hand and upper extremity conditions require continued investigation. The purpose of this article is to provide a general review of the mechanism of medical cannabis and a scoping review of the current evidence for its efficacy, safety, and potential applicability in hand and upper extremity conditions.

ASRA Pain Medicine consensus guidelines on the management of the perioperative patient on cannabis and cannabinoids

BACKGROUND

The past two decades have seen an increase in cannabis use due to both regulatory changes and an interest in potential therapeutic effects of the substance, yet many aspects of the substance and their health implications remain controversial or unclear.

METHODS

In November 2020, the American Society of Regional Anesthesia and Pain Medicine charged the Cannabis Working Group to develop guidelines for the perioperative use of cannabis. The Perioperative Use of Cannabis and Cannabinoids Guidelines Committee was charged with drafting responses to the nine key questions using a modified Delphi method with the overall goal of producing a document focused on the safe management of surgical patients using cannabinoids. A consensus recommendation required ≥75% agreement.

RESULTS

Nine questions were selected, with 100% consensus achieved on third-round voting. Topics addressed included perioperative screening, postponement of elective surgery, concomitant use of opioid and cannabis perioperatively, implications for parturients, adjustment in anesthetic and analgesics intraoperatively, postoperative monitoring, cannabis use disorder, and postoperative concerns. Surgical patients using cannabinoids are at potential increased risk for negative perioperative outcomes.

CONCLUSIONS

Specific clinical recommendations for perioperative management of cannabis and cannabinoids were successfully created.

Phase IIb Randomized, Placebo-Controlled, Dose-Escalating, Double-Blind Study of Cannabidiol Oil for the Relief of Symptoms in Advanced Cancer (MedCan1-CBD)

PURPOSE

To determine whether cannabidiol (CBD) oil can improve symptom distress in patients with advanced cancer receiving palliative care.

METHODS

Participants were adults with advanced cancer and symptom distress (Edmonton Symptom Assessment Scale [ESAS] total score of ≥ 10/90) who received titrated CBD oil 100 mg/mL, 0.5 mL once daily to 2 mL three times a day, or matched placebo for 28 days. The primary outcome was ESAS total symptom distress score (TSDS) at day 14. Response was defined as a decrease in TSDS by ≥ 6 at day 14. Secondary outcomes were ESAS TSDS over time, individual symptom scores, patient-determined effective dose, opioid use, Global Impression of Change, depression, anxiety, quality of life, and adverse events.

RESULTS

Of the 144 patients randomly assigned, the planned sample size of 58 participants on CBD and 63 on placebo reached the primary analysis point (day 14). The unadjusted change in TSDS from baseline to day 14 was -6.2 (standard deviation, 14.5) for placebo and -3.0 (standard deviation, 15.2) for CBD with no significant difference between arms (P = .24). Similarly, there was no detected difference in proportion of responders (placebo: 37 of 63 [58.7%], CBD: 26 of 58 [44.8%], P = .13). All components of ESAS improved (fell) over time with no difference between arms. The median dose of participant-selected CBD was 400 mg per day with no correlation with opioid dose. There was no detectable effect of CBD on quality of life, depression, or anxiety. Adverse events did not differ significantly between arms apart from dyspnea that was more common with CBD. Most participants reported feeling better or much better at days 14 (53% CBD and 65% placebo) and 28 (70% CBD and 64% placebo).

CONCLUSION

CBD oil did not add value to the reduction in symptom distress provided by specialist palliative care alone.

Impacts of medical and non-medical cannabis on the health of older adults: Findings from a scoping review of the literature

BACKGROUND

Cannabis legalization has enabled increased consumption in older adults. Age-related mental, physical, and physiological changes may lead to differences in effects of cannabis in older adults compared to younger individuals.

OBJECTIVE

To perform a scoping review to map the evidence regarding the health effects of cannabis use for medical and non-medical purposes in older adults.

METHODS

Electronic databases (MEDLINE, Embase, PsycINFO, Cochrane Library) were searched for systematic reviews (SRs), randomized controlled trials (RCTs) and non-randomized/observational studies (NRSs) assessing the health effects and associations of cannabis use (medical or non-medical) in adults ≥ 50 years of age. Included studies met age-related inclusion criteria or involved a priori identified health conditions common among older adults. Records were screened using a liberal accelerated approach and data charting was performed independently by two reviewers. Descriptive summaries, structured tables, effect direction plots and bubble plots were used to synthesize study findings.

FINDINGS

From 31,393 citations, 133 publications describing 134 unique studies (26 SRs, 36 RCTs, 72 NRSs) were included. Medical cannabis had inconsistent therapeutic effects in specific patient conditions (e.g., end-stage cancer, dementia), with a number of studies suggesting possible benefits while others found no benefit. For medical cannabis, harmful associations outnumbered beneficial, and RCTs reported more negative effects than NRSs. Cannabis use was associated with greater frequencies of depression, anxiety, cognitive impairment, substance use and problematic substance use, accidents/injuries, and acute healthcare use. Studies often were small, did not consistently assess harms, and did not adjust for confounding.

DISCUSSION

The effects of medical cannabis are inconsistent within specific patient conditions. For older adults, generally, the available evidence suggests cannabis use may be associated with greater frequencies of mental health issues, substance use, and acute healthcare use, and the benefit-to-risk ratio is unclear. Studies with a balanced assessment of benefits and harms may guide appropriate public health messaging to balance the marketing pressures of cannabis to older adults.

[Cannabinoids reduce opioid use in older patients with pain : Retrospective three-year analysis of data from a general practice]

BACKGROUND

Relevant data for the prescription and therapeutic effects of medical cannabinoids (CAM) are still missing in everyday medicine especially for elderly and geriatric patients.

AIM OF THE STUDY

Documentation of prescription (duration, age) of CAM (dronabinol, nabiximols, cannabinoid extracts) and co-medicated opioids in a doctor's office specializing in pain.

METHODS

Analysis of the consumption of opioids (morphine equivalent) and CAM (THC equivalent) for age and gender.

RESULTS

In all, 178 patients with chronic pain were treated for a period of 366 days (median; range 31-2590 days). Median age was 72 years (26-96 years); 115 were women (64.8%). Of these, 34 were younger than 65 years, 42 were 65-80 years and 40 were more than 80 years old. Of the 63 men, 29 were younger than 65 years, 24 were 65-80 years and 10 were older than 80 years. Indications for CAM were chronic pain and the limitations for opioids because of side effects and worsening of quality of life. To total of 1001 CAM were prescribed, 557 (55.6%) dronabinol as liquid, 328 (32.7%) as full spectrum extracts and 66 (6.6%) as oro-mucosal nabiximols spray. 50 prescriptions (5%) contained more than one CAM simultaneously. The daily consumption of dronabinol liquor and extracts were 9.6 mg/day (median), and of spray 13.6 mg. The dosage over time did not change in patients older than 64; in younger patients, there was a non-significant increasing trend. Women requested lower THC dosages compared to men (8.1 mg vs. 14.8 mg). Furthermore, 10 patients (5.6%) stopped CAM because of failing effectivity, 7 (3.9%) because of failing cost coverage and only 5 because of adverse side effects. 115 patients (65%) with CAM also received opioids a median 65 mg/day morphine equivalents. This opioid dosage was significantly reduced in course of time by 24 mg/day morphine equivalents or 50%. This reduction was independent on CAM dosage, age and gender.

DISCUSSION

Patients with chronic pain profit from long-term CAM which safely and significantly lower the consumption of comedicated opioids, even at low dosages (< 7.5 mg/day). For women, low-dose THC may be sufficient. Older patients benefit from CAM, and adverse effects do not limit the (chronic) use and prescription of CAM in the elderly.

Marijuana Use and its Effect on Clinical Outcomes and Revision Rates in Patients Undergoing Anterior Cervical Discectomy and Fusion

STUDY DESIGN

A retrospective cohort study.

OBJECTIVE

To determine if (1) preoperative marijuana use increased complications, readmission, or reoperation rates following anterior cervical discectomy and fusion (ACDF), (2) identify if preoperative marijuana use resulted in worse patient-reported outcome measures (PROMs), and (3) investigate if preoperative marijuana use affects the quantity of opioid prescriptions in the perioperative period.

SUMMARY OF BACKGROUND DATA

A growing number of states have legalized recreational and/or medical marijuana, thus increasing the number of patients who report preoperative marijuana use. The effects of marijuana on clinical outcomes and PROMs in the postoperative period are unknown.

METHODS

All patients 18 years of age and older who underwent primary one- to four-level ACDF with preoperative marijuana use at our academic institution were retrospectively identified. A 3:1 propensity match was conducted to compare patients who used marijuana versus those who did not. Patient demographics, surgical characteristics, clinical outcomes, and PROMs were compared between groups. Multivariate regression models measured the effect of marijuana use on the likelihood of requiring a reoperation and whether marijuana use predicted inferior PROM improvements at the one-year postoperative period.

RESULTS

Of the 240 patients included, 60 (25.0%) used marijuana preoperatively. Multivariate logistic regression analysis identified marijuana use (odds ratio=5.62, P <0.001) as a predictor of a cervical spine reoperation after ACDF. Patients who used marijuana preoperatively had worse one-year postoperative Physical Component Scores of the Short-Form 12 (PCS-12) ( P =0.001), Neck Disability Index ( P =0.003), Visual Analogue Scale (VAS) Arm ( P =0.044) and VAS Neck ( P =0.012). Multivariate linear regression found preoperative marijuana use did not independently predict improvement in PCS-12 (β=-4.62, P =0.096), Neck Disability Index (β=9.51, P =0.062), Mental Component Scores of the Short-Form 12 (MCS-12) (β=-1.16, P =0.694), VAS Arm (β=0.06, P =0.944), or VAS Neck (β=-0.44, P =0.617).

CONCLUSION

Preoperative marijuana use increased the risk of a cervical spine reoperation after ACDF, but it did not significantly change the amount of postoperative opioids used or the magnitude of improvement in PROMs.

LEVEL OF EVIDENCE

Levwl III.

Real-Time Monitoring of Cannabis and Prescription Opioid Co-Use Patterns, Analgesic Effectiveness, and the Opioid-Sparing Effect of Cannabis in Individuals With Chronic Pain

Despite a rapid expansion of cannabis use for pain management, how cannabis and prescription opioids are co-used and whether co-use improves analgesia and promotes reduction of opioid use in the daily lives of individuals with chronic pain is poorly understood. Based upon ecological momentary assessment (EMA), the present study examined 1) how pain and use of opioids and/or cannabis in the previous moment is associated with individuals' choice of opioids and/or cannabis in the next moment, 2) the effects of co-use on pain severity and pain relief, and 3) whether daily total opioid consumption differs on days when people only used opioids versus co-used. Adults with chronic pain (N = 46) using both opioids and cannabis who were recruited online completed a 30-day EMA. Elevated pain did not increase the likelihood of co-use in subsequent momentary assessments. Switching from sole use of either opioids and cannabis to co-use was common. Neither co-use nor sole use of either cannabis or opioids were associated with reductions in pain in the next moment. However, participants reported the highest daily perceived pain relief from co-use compared to cannabis and opioid use only. Post hoc analysis suggested recall bias as a potential source of this discrepant findings between momentary versus retrospective assessment. Lastly, there was no evidence of an opioid-sparing effect of cannabis in this sample. The present study shows preliminary evidence on cannabis and opioid co-use patterns, as well as the effects of co-use on pain and opoid dose in the real-world setting. PERSPECTIVE: This article presents the overall patterns and effects of co-using cannabis and prescription opioids among individuals with chronic pain employing ecological momentary assessment. There were conflicting findings on the association between co-use and analgesia. Co-use was not associated with a reduction in daily opioid consumption in this sample.

Use of Cannabis and Cannabinoids for Treatment of Cancer

The endocannabinoid system (ECS) is an ancient homeostasis mechanism operating from embryonic stages to adulthood. It controls the growth and development of many cells and cell lineages. Dysregulation of the components of the ECS may result in uncontrolled proliferation, adhesion, invasion, inhibition of apoptosis and increased vascularization, leading to the development of various malignancies. Cancer is the disease of uncontrolled cell division. In this review, we will discuss whether the changes to the ECS are a cause or a consequence of malignization and whether different tissues react differently to changes in the ECS. We will discuss the potential use of cannabinoids for treatment of cancer, focusing on primary outcome/care-tumor shrinkage and eradication, as well as secondary outcome/palliative care-improvement of life quality, including pain, appetite, sleep, and many more factors. Finally, we will complete this review with the chapter on sex- and gender-specific differences in ECS and response to cannabinoids, and equality of the access to treatments with cannabinoids.

Topical therapy for pain management in malignant fungating wounds: A scoping review

AIMS AND OBJECTIVES

To map and synthesise the existing literature on topical therapies for malignant fungating wounds pain management and the gaps involved.

BACKGROUND

Most cancer patients with malignant fungating wounds suffer from wound-related pain, affecting their quality of life. Unfortunately, even though pain is a relevant symptom in cancer and palliative care, little is currently known about topical treatments' availability and impact on pain management.

DESIGN

A scoping review following JBI® methodology METHODS: Searches were performed in CINAHL, LILACS, Embase, Web of Science, PubMed, Cochrane, NICE, Scopus, JBISRIR and grey literature, in English, Portuguese and Spanish, with no time limit. Two authors independently reviewed all citations and a third was called in case of divergence, and studies in adults with malignant fungal wounds reporting topical pain interventions were included. In addition, a data extraction tool for synthesis and thematic analysis was developed. This study followed the PRISMA-ScR Checklist.

RESULTS

Seventy publications were selected from 796 records retrieved from databases. The studies mainly included non-systematic reviews and case studies with only six clinical trials. According to the narrative synthesis, twenty therapies were identified, including the use of wound dressings (58.6%), analgesic drugs (55.7%), topical antimicrobials (25.7%), skin barriers (15.7%), cryotherapy (5.7%) and negative pressure wound therapy (4.3%). Therapies were recommended to be applied to the wound bed or the periwound skin. In 68.5% of the studies, a standardised assessment for pain was not described.

CONCLUSIONS

Topical therapies applied to malignant fungating wounds or periwound areas had been examined for pain management. However, their effectiveness was analysed in a few interventional studies, indicating the need for further primary studies to inform evidence-based practice.

IMPLICATION FOR PRACTICE

Highlighted topical therapies for clinical practice consideration are opioids, anaesthetics and antimicrobials, with positive results described in randomised clinical trials. This study did not include patients.

The cannabinoid agonist CB-13 produces peripherally mediated analgesia in mice but elicits tolerance and signs of central nervous system activity with repeated dosing

ABSTRACT

Activation of cannabinoid receptor type 1 (CB 1 ) produces analgesia in a variety of preclinical models of pain; however, engagement of central CB 1 receptors is accompanied by unwanted side effects, such as psychoactivity, tolerance, and dependence. Therefore, some efforts to develop novel analgesics have focused on targeting peripheral CB 1 receptors to circumvent central CB 1 -related side effects. In the present study, we evaluated the effects of acute and repeated dosing with the peripherally selective CB 1 -preferring agonist CB-13 on nociception and central CB 1 -related phenotypes in a model of inflammatory pain in mice. We also evaluated cellular mechanisms underlying CB-13-induced antinociception in vitro using cultured mouse dorsal root ganglion neurons. CB-13 reduced inflammation-induced mechanical allodynia in male and female mice in a peripheral CB 1 -receptor-dependent manner and relieved inflammatory thermal hyperalgesia. In cultured mouse dorsal root ganglion neurons, CB-13 reduced TRPV1 sensitization and neuronal hyperexcitability induced by the inflammatory mediator prostaglandin E 2 , providing potential mechanistic explanations for the analgesic actions of peripheral CB 1 receptor activation. With acute dosing, phenotypes associated with central CB 1 receptor activation occurred only at a dose of CB-13 approximately 10-fold the ED 50 for reducing allodynia. Strikingly, repeated dosing resulted in both analgesic tolerance and CB 1 receptor dependence, even at a dose that did not produce central CB 1 -receptor-mediated phenotypes on acute dosing. This suggests that repeated CB-13 dosing leads to increased CNS exposure and unwanted engagement of central CB 1 receptors. Thus, caution is warranted regarding therapeutic use of CB-13 with the goal of avoiding CNS side effects. Nonetheless, the clear analgesic effect of acute peripheral CB 1 receptor activation suggests that peripherally restricted cannabinoids are a viable target for novel analgesic development.

The Role of Cannabis, Cannabidiol and Other Cannabinoids in Chronic Pain. The Perspective of Physicians

Currently, there is a renewed interest in treatments with medical cannabis and cannabinoids. Based on an increasing number of publications over the last decades that permitted new insights into mechanisms, efficacy and safety of cannabinoids, the use of cannabinergic medications is authorised in an increasing number of European and non-European countries. The alleviation of chronic, painful conditions is, since thousands of years, one of the primary reasons for the use of cannabis. Depending on the country, a wide range of medicinal cannabis preparations are available:ranging from defined cultivars of medical cannabis, mainly varying in their THC:CBD ratio, that are inhaled or taken as whole plant extracts,to highly purified single cannabinoids, such as delta-9-tetrahydrocannabinol (THC) and cannabidiol (CBD),or mixtures of two enriched extracts, standardised to a 1:1 ratio of THC:CBD (nabiximols). Although conflicting opinions continue to exist, the majority of reviews in the past concluded that medical cannabis and cannabinoids play a significant role in the management of pain. Surprisingly, systematic studies to date do not support an "entourage effect" of the other plant constituents of cannabis (mainly terpenoids) in treatment of chronic pain. An emerging cannabinoid is CBD which is the only cannabinergic medication available at present that does not cause the typical "cannabis high"; it is not a "controlled substance". However, despite years of research, there is either no study or no well-conducted, head-to-head, comparison available between different cannabis cultivars, between pure cannabinoids, and between pure cannabinoids and extracts. It remains unanswered which is the optimal treatment approach.

Opioid-sparing effect of cannabinoids for analgesia: an updated systematic review and meta-analysis of preclinical and clinical studies

Cannabinoid co-administration may enable reduced opioid doses for analgesia. This updated systematic review on the opioid-sparing effects of cannabinoids considered preclinical and clinical studies where the outcome was analgesia or opioid dose requirements. We searched Scopus, Cochrane Central Registry of Controlled Trials, Medline, and Embase (2016 onwards). Ninety-two studies met the search criteria including 15 ongoing trials. Meta-analysis of seven preclinical studies found the median effective dose (ED₅₀) of morphine administered with delta-9-tetrahydrocannabinol was 3.5 times lower (95% CI 2.04, 6.03) than the ED₅₀ of morphine alone. Six preclinical studies found no evidence of increased opioid abuse liability with cannabinoid administration. Of five healthy-volunteer experimental pain studies, two found increased pain, two found decreased pain and one found reduced pain bothersomeness with cannabinoid administration; three demonstrated that cannabinoid co-administration may increase opioid abuse liability. Three randomized controlled trials (RCTs) found no evidence of opioid-sparing effects of cannabinoids in acute pain. Meta-analysis of four RCTs in patients with cancer pain found no effect of cannabinoid administration on opioid dose (mean difference -3.8 mg, 95% CI -10.97, 3.37) or percentage change in pain scores (mean difference 1.84, 95% CI -2.05, 5.72); five studies found more adverse events with cannabinoids compared with placebo (risk ratio 1.13, 95% CI 1.03, 1.24). Of five controlled chronic non-cancer pain trials; one low-quality study with no control arm, and one single-dose study reported reduced pain scores with cannabinoids. Three RCTs found no treatment effect of dronabinol. Meta-analyses of observational studies found 39% reported opioid cessation (95% CI 0.15, 0.64, I² 95.5%, eight studies), and 85% reported reduction (95% CI 0.64, 0.99, I² 92.8%, seven studies). In summary, preclinical and observational studies demonstrate the potential opioid-sparing effects of cannabinoids in the context of analgesia, in contrast to higher-quality RCTs that did not provide evidence of opioid-sparing effects.

A critical review of cannabis in medicine and dentistry: A look back and the path forward

Introduction

In the last two decades, our understanding of the therapeutic utility and medicinal properties of cannabis has greatly changed. This change has been accompanied by widespread cannabis use in various communities and different age groups, especially within the United States. With this increase, we should consider the potential effects of cannabis–hemp on general public health and how they could alter therapeutic outcomes.

Material and Methods

The present investigation examined cannabis use for recreational and therapeutic use and a review of pertinent indexed literature was performed. The focused question evaluates “how cannabis or hemp products impact health parameters and do they provide potential therapeutic value in dentistry, and how do they interact with conventional medicines (drugs).” Indexed databases (PubMed/Medline, EMBASE) were searched without any time restrictions but language was restricted to English.

Results

The review highlights dental concerns of cannabis usage, the need to understand the endocannabinoid system (ECS), cannabinoid receptor system, its endogenous ligands, pharmacology, metabolism, current oral health, and medical dilemma to ascertain the detrimental or beneficial effects of using cannabis–hemp products. The pharmacological effects of pure cannabidiol (CBD) have been studied extensively while cannabis extracts can vary significantly and lack empirical studies. Several metabolic pathways are affected by cannabis use and could pose a potential drug interaction. The chronic use of cannabis is associated with health issues, but the therapeutic potential is multifold since there is a regulatory role of ECS in many pathologies.

Conclusion

Current shortcomings in understanding the benefits of cannabis or hemp products are limited due to pharmacological and clinical effects not being predictable, while marketed products vary greatly in phytocompounds warrant further empirical investigation. Given the healthcare challenges to manage acute and chronic pain, this review highlights both cannabis and CBD‐hemp extracts to help identify the therapeutic application for patient populations suffering from anxiety, inflammation, and dental pain.

Cannabis use, pain interference, and prescription opioid receipt among persons with HIV: a target trial emulation study

Concomitant with expanded legalization, cannabis is increasingly used to treat chronic pain among persons with HIV (PWH), despite equivocal benefit in research limited by small sample sizes and short duration of follow-up. To address these limitations, among a sample of PWH with pain interference enrolled in the Veterans Aging Cohort Study, we performed a target trial emulation study to compare the impact of four cannabis use strategies on pain interference. Among those receiving long-term opioid therapy (LTOT), we also explored impact of these strategies on ≥ 25% LTOT dose reduction. Among the analytic sample (N = 1284), the majority were men with a mean age of 50. Approximately 31% used cannabis and 12% received LTOT at baseline. Adjusting for demographic and clinical factors, cannabis use in any of 4 longitudinal patterns was not associated with resolved pain interference over 12- to 24-month follow-up. Among 153 participants receiving LTOT at baseline, cannabis use at both baseline and follow-up was negatively associated with LTOT dose reduction compared to no use at both baseline and follow-up. These findings support other observational studies finding no association between cannabis use and improved chronic pain or LTOT reduction among PWH.

Medical Cannabis Use Reduces Opioid Prescriptions in Patients With Osteoarthritis

Background

Osteoarthritis (OA) can result in significant pain, requiring pain management with opioids. Medical cannabis (MC) has the potential to be an alternative to opioids for chronic pain conditions. This study investigates whether MC used in the management of OA-related chronic pain can reduce opioid utilization.

Methods

Forty patients with chronic OA pain were certified for MC. Average morphine milligram equivalents (MME) per day of opioid prescriptions filled within the six months prior to MC certification was compared to that of the six months after. Visual analog scale (VAS) for pain and Global Health scores were measured at baseline, three, and six months post MC certification.

Results

Average MME/day decreased from 18.2 to 9.8 (n=40, p<0.05). The percentage of patients who dropped to 0 MME/day was 37.5%. VAS scores decreased significantly at three and six months, and Global Physical Health score increased significantly by three months.

Conclusions

MC reduces opioid prescription for patients with chronic OA pain and improves pain and quality of life.

Medical Cannabis Use Reduces Opioid Prescriptions in Patients With Chronic Back Pain

Background

This study investigates whether the use of medical cannabis (MC) in patients with chronic back pain is associated with a decreased opioid prescription.

Methods

The study included 186 patients with chronic back pain who were certified for MC use. The average morphine milligram equivalent (MME)/day of opioid prescriptions filled within the six months prior to MC certification was compared to that of six months after. Pain and disability questionnaires were distributed at three, six, and nine months post-certification.

Results

Patients who started at less than 15 MME/day and patients who started at greater than 15 MME/day decreased from 15.1 to 11.0 (n = 186, p < 0.01), 3.5 to 2­­­.1 (n = 134, p < 0.01), and 44.9 to 33.9 (n = 52, p < 0.01), respectively. Pain and disability scores were improved at follow-up as well.

Conclusion

MC use reduces opioid prescription for patients with chronic back pain and improves pain and disability scores.

Legal status of recreational cannabis and self-reported substitution of cannabis for opioids or prescription pain medication in Canada and the United States

Aims: With increased liberalization of cannabis policies in North America, there is growing interest in the use of cannabis to manage pain instead of opioids. The objectives of the study were to (1) examine the use of cannabis for pain relief in Canada and the United States (US) in 2018 and 2019; (2) examine the association between recreational cannabis laws and changes in the use of cannabis for pain relief, instead of opioids or prescription pain medication. Methods: Repeat cross-sectional survey data were used from Wave 1 and Wave 2 of the International Cannabis Policy Study conducted in 2018 and 2019 in Canada and the US. Respondents were recruited through commercial panels, aged 16-65, and had ever tried cannabis (N = 44,119). Weighted binary logistic regression models examined the association between the legal status of recreational cannabis and cannabis use for pain relief instead of opioids or prescription pain medication (n = 15,092). Results: Between 14-33% of cannabis consumers in Canada and the US reported using cannabis to manage headaches or pain. Of these consumers, 79% and 78% respondents in Canada; 80% and 83% in US illegal states; and 83% and 84% in US legal states, in 2018 and 2019, respectively, reported cannabis use for pain relief instead of opioids or prescription pain medication. There was little evidence of an association between the legal status of recreational cannabis and cannabis use for pain relief instead of opioids or prescription pain medication, among Canadian (AOR = 0.98, 95% CI: 0.78, 1.22) and US respondents (AOR = 1.11, 95% CI: 0.96, 1.28). Conclusions: Although substitution of cannabis for opioids or prescription pain medication is common among those who use cannabis for pain, there does not seem to be a significant difference according to cannabis legality. Future research should examine cannabis and opioid substitution using different research designs and time frames.

Medical Cannabis Patients Report Improvements in Health Functioning and Reductions in Opiate Use

Purpose: Opioid use rates have dropped as North American patients gain access to medical cannabis, indicating a harm reduction role, yet health outcomes remain mostly unexplored. This study presents self-reported medical cannabis use, perceptions of health functioning, and changes in opioid pain medication use in Florida medical cannabis patients.Methods: Patients (n = 2,183) recruited from medical dispensaries across Florida completed a 66-item cross-sectional survey that included demographic, health, and medication usage items, along with items from the Medical Outcomes Survey (SF-36) to assess health functioning before and after cannabis initiation.Results: Most participants were between the ages of 20 and 70 years of age (95%), over 54% were female, 47% were employed, and most (85%) were white. Commonly reported ailment groups were Pain and Mental Health combined (47.92%), Mental Health (28.86%) or Pain (9.07%). Health domains of bodily pain, physical functioning, and social functioning improved while limitations due to physical and emotional problems were unchanged. Most patients rated medical cannabis as being important to their quality of life. Many (60.98%) reported using pain medications prior to medical cannabis, 93.36% of these reported a change in pain medication after medical cannabis. The majority of participants (79%) reported either cessation or reduction in pain medication use following initiation of medical cannabis and 11.47% described improved functioning.Conclusions: The findings suggest that some medical cannabis patients decreased opioid use without harming quality of life or health functioning, soon after the legalization of medical cannabis. The public health implications of medical cannabis as an alternative pain medication are discussed.