Medical cannabis use in the United States: a retrospective database study

Clinical Benefits and Safety of Medical Cannabis Products: A Narrative Review on Natural Extracts

Interest in medical cannabis and cannabis-based medicinal products (CBMPs) has increased greatly in recent years. Two cannabinoids are of principal importance; delta-9-tetrahydrocannabinol (∆9-THC), the primary psychoactive component, and also cannabidiol (CBD), considered non-intoxicating. Each has distinct mechanisms of action and different therapeutic potentials. CBMPs differ in their ∆9-THC and CBD components; predominantly ∆9-THC, balanced formulations with equivalent ∆9-THC and CBD elements, and CBD-predominant products. In this narrative review, we evaluate the published evidence for the clinical benefits of CBMPs and overall benefits in well-being. We also review the overall safety profile and discuss the potential for dependence with CBMPs. Evidence can be drawn from a wide range of randomized and other controlled studies and from observational real-world studies. Most data from observational registry studies are supportive of ∆9-THC-based products (∆9-THC-predominant or balanced CBMPs) in the management of chronic neuropathic pain. Balanced products are also effective in reducing spasticity in multiple sclerosis. Most CBMPs show benefit in providing symptomatic benefits in reducing anxiety, nausea, and in improving sleep, but the place of specific products is more subtle, and choice guided by specific circumstances. Symptomatic improvements are accompanied by improved quality of life and well-being. Safety data indicate that CBMPs are generally well tolerated in most patients without specific contraindications. The majority of adverse effects are non-serious, and transient; most are principally associated with ∆9-THC and are dose-dependent. In contrast to recreational cannabis use, there is little evidence from clinical studies that CBMPs have any potential for dependence.

The Estrous Cycle Influences the Effects of Fatty Acid Amide Hydrolase and Monoacylglycerol Lipase Inhibition in the Anxiety-Like Behavior in Rats

Background: Sex differences in the response to the anxiety-related effects of cannabinoid drugs have been reported, with females being more sensitive than males. Evidence suggests that, according to sex and estrous cycle phase (ECP), the content of the endocannabinoids (eCBs) N-arachidonoylethanolamine (AEA) and 2-arachidonoylglycerol (2-AG) varies in brain areas involved in the anxiety-like behavior. Methods: Considering the lack of studies evaluating sex and ECP differences in the eCB system in anxiety, using URB597, a fatty acid amide hydrolase inhibitor, or MJN110, a monoacylglycerol lipase inhibitor, we explored the effects of increasing AEA or 2-AG levels, respectively, in cycling and ovariectomized (OVX) female adult Wistar rats, as well as males, subjected to the elevated plus maze. Results: The administration of URB597 (0.1 or 0.3mg/kg; intraperitoneally) either increased or reduced the percentage of open arms time (%OAT) and open arms entries (%OAE), being anxiolytic in diestrus and anxiogenic in estrus. No effects were observed in proestrus or when all ECPs were analyzed together. Both doses produced anxiolytic-like effects in males. In OVX females, the anxiolytic-like effect of URB597 0.1 was associated with low levels of estradiol, whereas the anxiogenic-like effect of URB597 0.3 was spared by estradiol pretreatment. The systemic administration of MJN110 3.0 mg/kg reduced the risk assessment behavior (RAB), suggesting an anxiolytic-like effect independent of the ECP. When considering the ECP, MJN110 3.0 increased the %OAT and reduced the RAB, being anxiolytic in estrus and diestrus. No effects were observed in proestrus. Both doses of MJN110 were anxiogenic in males. In OVX females, the anxiolytic-like effect of MJN110 was dependent on low estradiol levels. Conclusion: Together, our findings support the evidence that females react differently to the effects of cannabinoids in the anxiety-like behavior; in addition, AEA and 2-AG modulation elicits anxiety-like responses that are closely influenced by hormone levels, mainly estradiol.

Medical Cannabis Patients Under the Age of 21 in the United States: Description of Demographics and Conditions from a Large Patient Database, 2019-2023

Introduction

Existing research on medical cannabis patients has often overlooked those younger than 21. This study aimed to detail the frequency and rate of pediatric medical cannabis patients in the US using a large patient database.

Methods

Utilizing Leafwell Patient Database data from 2019 to mid-2023, we described demographics and qualifying conditions, employing descriptive statistics and χ2 tests to discern differences between minors (0-17 years) and young adults (18-20 years). We calculated rates per 100,000 population by state.

Results

Analyzing 13,855 patients, 5.7% were minors and 94.3% were young adults. Anxiety emerged as the primary self-reported condition for both groups, yet differences were seen for other conditions. Differences were observed by race/ethnicity, health insurance status, residency in adult-use states, and number of reported conditions. Notably, both groups reported a similar average number of conditions.

Conclusion

This study underscores demographic distinctions between minor-aged medical cannabis patients and young adults. There is a need for comprehensive clinical research addressing efficacy, safety, and tailored guidelines specific for pediatric medical cannabis patients. Such insights are pivotal for healthcare providers and policymakers in navigating medical cannabis treatment protocols.

Overview of global monitoring systems for the side effects and adverse events associated with medicinal cannabis use: a scoping review using a systematic approach

OBJECTIVES

The use of cannabis-based medicine (CBM) as a therapeutic has surged in Australia over the past 5 years. Historically, the United Nations Single Convention on Narcotic Drugs (1961) prohibited cannabis use in Europe, the USA, the UK and Australia, leading to legislative resistance and limited preclinical data on CBM. Existing safety monitoring systems for CBM are poorly structured and do not integrate well into the workflows of busy health professionals. As a result, postmarketing surveillance is inconsistent. This review aims to evaluate international systems for monitoring CBM side effects and adverse events.

DESIGN

To undertake a scoping review with a systematic approach, we used the Population, Intervention, Comparison, Outcome (PICO) framework to develop keyword elements, and two search queries to maximise search sensitivity and specificity.

DATA SOURCES

Search queries were entered into Embase and Scopus for peer-reviewed literature, and additional searches for grey literature were conducted on 23 June 2023.

ELIGIBILITY CRITERIA

We included 54 full-text articles in the review: 39 from peer-reviewed searches, 8 from grey literature and 7 from citations of relevant texts.

DATA EXTRACTION AND SYNTHESIS

Our search yielded two main forms of monitoring systems: databases and registries. Out of the 24 monitoring systems identified, there were 10 databases and 14 registries, with databases often created by regulatory authorities. Systems differed in methods of causality assessment, level of detail collected, terminology and affiliations.

RESULTS

Within the monitoring systems with enough published data for analysis, all except one remain active at the time of this review. VigiBase is the largest centralised monitoring system, receiving international case reports, however data heterogeneity persists.

CONCLUSIONS

Our study emphasises the need for a centralised, consistent and accessible system for the postmarketing surveillance of side effects and adverse events associated with medicinal cannabis use.

Factors Associated with Medical Cannabis Use After Certification: A Three-Month Longitudinal Study

Background: Over the past decade, there has been increased utilization of medical cannabis (MC) in the United States. Few studies have described sociodemographic and clinical factors associated with MC use after certification and more specifically, factors associated with use of MC products with different cannabinoid profiles. Methods: We conducted a longitudinal cohort study of adults (N=225) with chronic or severe pain on opioids who were newly certified for MC in New York State and enrolled in the study between November 2018 and January 2022. We collected data over participants' first 3 months in the study, from web-based assessment of MC use every 2 weeks (unit of analysis). We used generalized estimating equation models to examine associations of sociodemographic and clinical factors with (1) MC use (vs. no MC use) and (2) use of MC products with different cannabinoid profiles. Results: On average, 29% of the participants used predominantly high delta-9-tetrahydrocannabinol (THC) MC products within the first 3 months of follow-up, 30% used other MC products, and 41% did not use MC products. Non-Hispanic White race, pain at multiple sites, and past 30-day sedative use were associated with a higher likelihood of MC use (vs. no MC use). Current tobacco use, unregulated cannabis use, and enrollment in the study during the COVID-19 pandemic were associated with a lower likelihood of MC use (vs. no MC use). Among participants reporting MC use, female gender and older age were associated with a lower likelihood of using predominantly high-THC MC products (vs. other MC products). Conclusion: White individuals were more likely to use MC after certification, which may be owing to access and cost issues. The findings that sedative use was associated with greater MC use, but tobacco and unregulated cannabis were associated with less MC use, may imply synergism and substitution that warrant further research. From the policy perspective, additional measures are needed to ensure equitable availability of and access to MC. Health practitioners should check patients' history and current use of sedative, tobacco, and unregulated cannabis before providing an MC recommendation and counsel patients on safe cannabis use. clinicaltrials.gov (NCT03268551).

Terpenes from Cannabis sativa induce antinociception in a mouse model of chronic neuropathic pain via activation of adenosine A2A receptors

ABSTRACT

Terpenes are small hydrocarbon compounds that impart aroma and taste to many plants, including Cannabis sativa. A number of studies have shown that terpenes can produce pain relief in various pain states in both humans and animals. However, these studies were methodologically limited and few established mechanisms of action. In our previous work, we showed that the terpenes geraniol, linalool, β-pinene, α-humulene, and β-caryophyllene produced cannabimimetic behavioral effects via multiple receptor targets. We thus expanded this work to explore the potential antinociception and mechanism of these Cannabis terpenes in a mouse model of chronic pain. We first tested for antinociception by injecting terpenes (200 mg/kg, IP) into male and female CD-1 mice with mouse models of chemotherapy-induced peripheral neuropathy (CIPN) or lipopolysaccharide-induced inflammatory pain, finding that the terpenes produced roughly equal antinociception to 10 mg/kg morphine or 3.2 mg/kg WIN55,212. We further found that none of the terpenes produced reward as measured by conditioned place preference, while low doses of terpene (100 mg/kg) combined with morphine (3.2 mg/kg) produced enhanced antinociception vs either alone. We then used the adenosine A2A receptor (A2AR) selective antagonist istradefylline (3.2 mg/kg, IP) and spinal cord-specific CRISPR knockdown of the A2AR to identify this receptor as the mechanism for terpene antinociception in CIPN. In vitro cAMP and binding studies and in silico modeling studies further suggested that the terpenes act as A2AR agonists. Together these studies identify Cannabis terpenes as potential therapeutics for chronic neuropathic pain and identify a receptor mechanism for this activity.

Cannabinoid-Induced Inhibition of Morphine Glucuronidation and the Potential for In Vivo Drug-Drug Interactions

Opioids are commonly prescribed for the treatment of chronic pain. Approximately 50% of adults who are prescribed opioids for pain co-use cannabis with their opioid treatment. Morphine is primarily metabolized by UDP-glucuronosyltransferase (UGT) 2B7 to an inactive metabolite, morphine-3-glucuronide (M3G), and an active metabolite, morphine-6-glucuronide (M6G). Previous studies have shown that major cannabis constituents including Δ9-tetrahydrocannabinol (THC) and cannabidiol (CBD) inhibit major UGT enzymes. To examine whether cannabinoids or their major metabolites inhibit morphine glucuronidation by UGT2B7, in vitro assays and mechanistic static modeling were performed with these cannabinoids and their major metabolites including 11-hydroxy-Δ9-tetrahydrocannabinol (11-OH-THC), 11-nor-9-carboxy-Δ9-tetrahydrocannabinol (11-COOH-THC), 7-hydroxy-cannabidiol (7-OH-CBD), and 7-carboxy-cannabidiol (7-COOH-CBD). In vitro assays with rUGT-overexpressing microsomes and human liver microsomes showed that THC and CBD and their metabolites inhibited UGT2B7-mediated morphine metabolism, with CBD and THC exhibiting the most potent Ki,u values (0.16 µM and 0.37 µM, respectively). Only 7-COOH-CBD exhibited no inhibitory activity against UGT2B7-mediated morphine metabolism. Static mechanistic modeling predicted an in vivo drug-drug interaction between morphine and THC after inhaled cannabis, and between THC, CBD, and 7-OH-CBD after oral consumption of cannabis. These data suggest that the co-use of these agents may lead to adverse drug events in humans.

Medicinal cannabis for treating post-traumatic stress disorder and comorbid depression: real-world evidence

BACKGROUND

Cannabis-based medicinal products (CBMPs) are increasingly being used to treat post-traumatic stress disorder (PTSD), despite limited evidence of their efficacy. PTSD is often comorbid with major depression, and little is known about whether comorbid depression alters the effectiveness of CBMPs.

AIMS

To document the prevalence of depression among individuals seeking CBMPs to treat PTSD and to examine whether the effectiveness of CBMPs varies by depression status.

METHOD

Data were available for 238 people with PTSD seeking CBMP treatment (5.9% of the treatment-seeking sample) and 3-month follow-up data were available for 116 of these. Self-reported PTSD symptoms were assessed at treatment entry and at 3-month follow-up using the PTSD Checklist - Civilian Version (PCL-C). The probable presence of comorbid depression at treatment entry was assessed using the nine-item Patient Health Questionnaire (PHQ-9). Additional data included sociodemographic characteristics and self-reported quality of life.

RESULTS

In total, 77% met screening criteria for depression, which was associated with higher levels of PTSD symptomatology (mean 67.8 v. 48.4, F(1,236) = 118.5, P < 0.001) and poorer general health, quality of life and sleep. PTSD symptomatology reduced substantially 3 months after commencing treatment (mean 58.0 v. 47.0, F(1,112) = 14.5, P < 0.001), with a significant interaction (F(1,112) = 6.2, P < 0.05) indicating greater improvement in those with depression (mean difference 15.3) than in those without (mean difference 7).

CONCLUSIONS

Depression is common among individuals seeking CBMPs to treat PTSD and is associated with greater symptom severity and poorer quality of life. Effectiveness of CBMPs for treating PTSD does not appear to be impaired in people with comorbid depression.

Available but inaccessible: patient experiences during the first 2 years of a primary care-based medical cannabis program at an academic medical center

BACKGROUND

Medical cannabis use and public acceptance in the United States have increased over the past 25 years. However, access to medical cannabis remains limited, particularly for underserved populations. To understand how patients experience medical cannabis accessibility, we measured medical cannabis use and barriers to use after medical cannabis certification in an urban safety-net academic medical center.

METHODS

We conducted a retrospective cohort study among patients seen in Montefiore's Medical Cannabis Program (MMCP) from 2017 to 2019. Patient demographic and clinical characteristics, as well purchase history of medical cannabis, were extracted from electronic medical records. We also administered a phone questionnaire to a subset of patients to assess usage patterns, effectiveness, and barriers to medical cannabis use.

RESULTS

Among 562 patients who were newly certified for medical cannabis between 2017 and 2019, 45% purchased medical cannabis, while 55% did not. Patients who purchased medical cannabis were more likely to be white and have private insurance or Medicare. Unregulated cannabis use and current tobacco use were less common among those who purchased medical cannabis. In multivariable logistic regression analysis, unregulated cannabis use remained negatively associated with purchasing medical cannabis. Patients reported that affordability and dispensary accessibility were their main barriers to purchasing medical cannabis.

CONCLUSION

Among patients certified for medical cannabis use, fewer than half purchased medical cannabis after certification. Improving access to medical cannabis is crucial for ensuring equitable access to regulated cannabis, and to reducing unregulated cannabis use.

The Quebec Cannabis Registry: Investigating the Safety and Effectiveness of Medical Cannabis

Objective: To investigate the safety and effectiveness of medical cannabis (MC) in the real-world clinical practice setting. Design: A 4-year prospective noncomparative registry of adult patients who initiated MC for a variety of indications. This paper reports on patients followed for up to 12 months, with interim visits at 3, 6, and 9 months after enrollment. Setting: Public or private outpatient clinics certified to authorize MC in the province of Quebec, Canada. Participants: Overall, 2991 adult (age ≥18 years) patients (mean age 51 years; 50.2% women) were enrolled between May 2015 and October 2018, with the last follow-up ending in May 2019. Interventions/Exposures: Cannabis products (dried, oil, or other) purchased from a Canadian licensed cannabis producer as authorized by physicians. Main Outcome Measures: The primary outcomes were self-reported pain severity, interference and relief (Brief Pain Inventory [BPI]), symptoms using the Revised Edmonton Symptom Assessment System (ESAS-r) and health-related quality of life dimensions (EQ-5D-5L) at baseline and each follow-up visit. The secondary outcomes were self-reported adverse events (AEs) and characteristics of cannabis treatment. Results: All patient-reported outcomes (BPI, ESAS-r, and EQ-5D-5L) showed a statistically significant improvement at 3 months (all p<0.01), which was maintained or further improved (for pain interference, tiredness, and well-being) over the remainder of the 12-month follow-up. Results also revealed clinically significant improvements in pain interference and tiredness, anxiety, and well-being from baseline. There were 79 AE reports (77 patients), 16 met the regulatory definition of seriousness, in which only 8 AEs were certainly or probably related to MC. Conclusions: MC directed by physicians appears to be safe and effective within 3 months of initiation for a variety of medical indications.

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.

Perceived Effectiveness of Medical Cannabis Among Adults with Chronic Pain: Findings from Interview Data in a Three-Month Pilot Study

Objectives

Patient-reported outcomes are critical to evaluate the effectiveness of medical cannabis as an alternative treatment for chronic pain. This study examined the perceived effectiveness of medical cannabis for chronic pain management among middle-aged and older adults newly initiating medical cannabis.

Methods

Interview data from participants in a three-month pilot study were analyzed to assess the perceived effectiveness of medical cannabis on chronic pain and related outcomes. The interview was conducted after approximately one month of usage and responses were analyzed using the RADaR (Rigorous and Accelerated Data Reduction) technique.

Results

51 adults initiating medical cannabis for chronic pain were interviewed (24 women, 27 men, mean age 54.4, SD = 12.0), with the majority (n=41) identifying as Non-Hispanic White followed by Non-Hispanic Black (n=7), Multi-racial (2), Hispanic White (1). Most study participants (62.7%) reported MC being overall effective. Common benefits included reduced pain intensity, anxiety, and dependency on pain and psychiatric medications. Improvements in physical functioning, sleep quality, and mood were reported. Common challenges included difficulty finding a suitable product or dose, experiencing side effects such as 'undesired high', 'stomach issues', and a limited 'threshold of pain' treatable by the product.

Discussion

Findings suggest most participants perceived medical cannabis to be overall effective for chronic pain management. Participants reported improved physical and mental functioning and reduced use of pain and psychiatric medications. Future research systematically assessing side effects, dosage and mode of consumption is needed to further evaluate the outcomes among adults initiating medical cannabis.

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.

Acute Toxicity and Pharmacokinetic Profile of an EU-GMP-Certified Cannabis sativa L. in Rodents

The conundrum of Cannabis sativa's applications for therapeutical purposes is set apart by the hundreds of known and commercially available strains, the social, cultural and historical context, and the legalization of its use for medical purposes in various jurisdictions around the globe. In an era where targeted therapies are continuously being developed and have become the norm, it is imperative to conduct standardized, controlled studies on strains currently cultivated under Good Manufacturing Practices (GMP) certification, a standard that guarantees the quality requirements for modern medical and therapeutic use. Thus, the aim of our study is to evaluate the acute toxicity of a 15.6% THC: <1% CBD, EU-GMP certified, Cannabis sativa L. in rodents, following the OECD acute oral toxicity guidelines, and to provide an overview of its pharmacokinetic profile. Groups of healthy female Sprague-Dawley rats were treated orally with a stepwise incremental dose, each step using three animals. The absence or presence of plant-induced mortality in rats dosed at one step determined the next step. For the EU GMP-certified Cannabis sativa L. investigated, we determined an oral LD50 value of over 5000 mg/kg in rats and a human equivalent oral dose of ≈806.45 mg/kg. Additionally, no significant clinical signs of toxicity or gross pathological findings were observed. According to our data, the toxicology, safety and pharmacokinetic profile of the tested EU-GMP-certified Cannabis sativa L. support further investigations through efficacy and chronic toxicity studies in preparation for potential future clinical applications and especially for the treatment of chronic pain.

Terpenes from Cannabis sativa Induce Antinociception in Mouse Chronic Neuropathic Pain via Activation of Spinal Cord Adenosine A2A Receptors

Terpenes are small hydrocarbon compounds that impart aroma and taste to many plants, including Cannabis sativa. A number of studies have shown that terpenes can produce pain relief in various pain states in both humans and animals. However, these studies were methodologically limited and few established mechanisms of action. In our previous work, we showed that the terpenes geraniol, linalool, β-pinene, α-humulene, and β-caryophyllene produced cannabimimetic behavioral effects via multiple receptor targets. We thus expanded this work to explore the efficacy and mechanism of these Cannabis terpenes in relieving chronic pain. We first tested for antinociceptive efficacy by injecting terpenes (200 mg/kg, IP) into male and female CD-1 mice with chemotherapy-induced peripheral neuropathy (CIPN) or lipopolysaccharide-induced inflammatory pain, finding that the terpenes produced roughly equal efficacy to 10 mg/kg morphine or 3.2 mg/kg WIN55,212. We further found that none of the terpenes produced reward as measured by conditioned place preference, while low doses of terpene (100 mg/kg) combined with morphine (3.2 mg/kg) produced enhanced antinociception vs. either alone. We then used the adenosine A2A receptor (A2AR) selective antagonist istradefylline (3.2 mg/kg, IP) and spinal cord-specific CRISPR knockdown of the A2AR to identify this receptor as the mechanism for terpene antinociception in CIPN. In vitro cAMP and binding studies and in silico modeling studies further suggested that the terpenes act as A2AR agonists. Together these studies identify Cannabis terpenes as potential therapeutics for chronic neuropathic pain, and identify a receptor mechanism in the spinal cord for this activity.

Patient priorities for research: A focus group study of UK medical cannabis patients

INTRODUCTION

There has yet to be an evaluation of medical cannabis patient preferences with respect to future research. As such, prioritisation of research agendas has been largely driven by academia and industry. The primary aim of this study was to elicit priorities for research from medical cannabis patients in the United Kingdom (UK).

METHODS

Patients undergoing active treatment for health conditions with medical cannabis in the UK were invited to take part in focus groups from December 2021 to February 2022. An inductive thematic analysis of responses was performed. Participants also completed a ranking exercise whereby they assigned ten counters (each equivalent to £1 million GBP) to competing research priorities.

RESULTS

30 medical cannabis patients participated across 3 focus groups. The following themes were identified as research priorities: adverse events, comparison between cannabis-based medicinal products, health conditions, pharmacology of cannabis, types of study, healthcare professionals' attitudes, social environment, agriculture and manufacturing, and the cannabis plant. Participants assigned the highest proportion of research funding to 'assessment of effect on specific symptoms' (26 counters; 8.7%).

CONCLUSIONS

This study highlighted specific themes within which to focus future research on medical cannabis. Clinically, there was a directive towards ensuring that research is condition- or symptom-specific. Participants also emphasised themes on the social impact of medical cannabis, such as knowledge of medical cannabis among healthcare professionals, stigma, and effects on driving and in the workplace. These findings can guide both research funders and researchers into effectively conducting research which fits within a more patient-centric model.

The role of cannabis clinics in the health system: a qualitative study of physicians' views in New Zealand

BACKGROUND

Privately-owned cannabis clinics have sprung up in many jurisdictions where medicinal cannabis has been legalised and provide an alternative pathway for patients who are unable or unwilling to access a prescription for cannabis-based medicinal products from their usual healthcare providers.

AIMS

This study aimed to explore physicians' views on cannabis clinics, including their perceptions of the role cannabis clinics play in the wider health system.

METHODS

A qualitative study using in-depth, semi-structured interviews with thirty-one physicians affiliated with private and community clinics in New Zealand (including cannabis clinicians, GPs, and specialist doctors). The interviews were conducted from July to December 2021. Data were transcribed and analysed using inductive thematic analysis.

RESULTS

Cannabis clinicians positioned themselves as (1) "service providers", facilitating consumer access to cannabis prescriptions and products, and (2) "educators", providing advice to patients and the wider physician community. While general practitioners and specialists recognised the benefits of specialised cannabis clinics (i.e., knowledge of products and a non-judgmental environment), they questioned the limited evidence of clinical efficacy for cannabis, potential financial conflicts of interests of cannabis clinicians that may blur their clinical judgement, and the risk of compartmentalising patients' healthcare.

CONCLUSIONS

Our paper raises a number of challenges with attempting to integrate cannabis clinics into the wider health system.

Making a joint decision: Cannabis as a potential substitute for opioids in obstetrics and gynecology

There is a growing body of evidence that cannabis may be effective as an analgesic with potential to reduce opioid usage in chronic pain. This review synthesizes the available literature to elucidate the possible role that cannabis might play in reducing opioid use in gynecological disorders that may potentially lead to a recommendation of substituting opioids with cannabis. With reports of a decrease in opioid use after cannabis initiation, an opioid-sparing effect has been seen in gynecologic malignancies such as ovarian, uterine, endometrial, and cervical cancers, in addition to chronic pelvic pain (CPP). Though many studies have found an association between cannabis and various adverse maternal and neonatal outcomes, there is a lack of randomized controlled trials making it difficult to claim a directly causal relationship between cannabis and these adverse outcomes. Additionally, with increased use of cannabis during pregnancy, the evidence of possible benefits and risks to mothers and fetuses is examined.

A large Australian longitudinal cohort registry demonstrates sustained safety and efficacy of oral medicinal cannabis for at least two years

Introduction

Oral medicinal cannabis (MC) has been increasingly prescribed for a wide range of clinical conditions since 2016. Despite an exponential rise in prescriptions and publications, high quality clinical efficacy and safety studies are lacking. The outcomes of a large Australian clinical electronic registry cohort are presented.

Methods

A prospective cannabis-naïve patient cohort prescribed oral MC participated in an ongoing longitudinal registry at a network of specialised clinics. Patient MC dose, safety and validated outcome data were collected regularly over two years and analysed.

Results

3,961 patients (mean age 56.07 years [SD 19.08], 51.0% female) with multimorbidity (mean diagnoses 5.14 [SD 4.08]) and polypharmacy (mean 6.26 medications [SD 4.61]) were included in this analysis. Clinical indications were for: chronic pain (71.9%), psychiatric (15.4%), neurological (2.1%), and other diagnoses (10.7%). Median total oral daily dose was 10mg for Δ9-tetrahydrocannabinol (THC) and 22.5mg for cannabidiol (CBD). A stable dose was observed for over two years. 37.3% experienced treatment related adverse events. These were graded mild (67%), moderate (31%), severe (<2%, n = 23) and two (0.1%) serious adverse events. Statistically significant improvements at a p value of <0.001 across all outcomes were sustained for over two years, including: clinical global impression (CGI-E, +39%: CGI-I, +52%; p<0.001), pain interference and severity (BPI, 26.1% and 22.2%; p<0.001), mental health (DASS-21, depression 24.5%, anxiety 25.5%, stress 27.7%; p<0.001), insomnia (ISI, 35.0%; p<0.001), and health status (RAND SF36: physical function, 34.4%: emotional well-being, 37.3%; p<0.001). Mean number of concomitant medications did not significantly change over 2 years (p = 0.481).

Conclusions

Oral MC was demonstrated to be safe and well-tolerated for a sustained period in a large complex cohort of cannabis-naïve, multimorbid patients with polypharmacy. There was significant improvement (p<0.001) across all measured clinical outcomes over two years. Results are subject to limitations of Real World Data (RWD) for causation and generalisability. Future high quality randomised controlled trials are awaited.

Regulation of glutamate homeostasis in the nucleus accumbens by astrocytic CB1 receptors and its role in cocaine-motivated behaviors

Cannabinoid type 1 receptors (CB1Rs) orchestrate brain reward circuitry and are prevalent neurobiological targets for endocannabinoids and cannabis in the mammalian brain. Decades of histological and electrophysiological studies have established CB1R as presynaptic G-protein coupled receptors (GPCRs) that inhibit neurotransmitter release through retrograde signaling mechanisms. Recent seminal work demonstrates CB1R expression on astrocytes and the pivotal function of glial cells in endocannabinoid-mediated modulation of neuron-astrocyte signaling. Here, we review key facets of CB1R-mediated astroglia regulation of synaptic glutamate transmission in the nucleus accumbens with a specific emphasis on cocaine-directed behaviors.

Medical cannabis use in Canada and its impact on anxiety and depression: A retrospective study

This was a retrospective study of patients utilizing medical cannabis who received their medical cannabis documentation and allotment from a Harvest Medicine clinic in Canada to determine the impact of medical cannabis on anxiety and depression outcomes. Patients included in the study were at least 18 years of age with completed validated questionnaires for anxiety (GAD-7) and depression (PHQ-9) at their initial evaluation and at least one follow-up visit. There were 7,362 patients included in the sample, of which the average age was 49.8 years, and 53.1% were female. There were statistically significant improvements between baseline and follow-up scores for both the GAD-7 and PHQ-9, with larger improvements seen for patients who were actively seeking medical cannabis to treat anxiety or depression. From 12 months on, those reporting anxiety had an average decrease in GAD-7 scores that was greater than the minimum clinically important difference of 4, and the same was seen for patients reporting depression from 18 months on, with the average decrease in PHQ-9 scores more than the MCID minimum clinically important difference of 5. This study provides some evidence to support the effectiveness of medical cannabis as a treatment for anxiety and depression.

Developing a real-world evidence base for prescribed cannabis in the United Kingdom: preliminary findings from Project Twenty21

The therapeutic potential of medical cannabis to treat a variety of conditions is becoming increasingly recognised. Globally, a large number of countries have now legalised cannabis for medical uses and a substantial number of patients are able to access their medications. Yet in the UK, where medical cannabis was legalised in November 2018, only a handful of NHS prescriptions have been written, meaning that most patients are unable to access the medicine. Reasons for this are manyfold and include the perceived lack of clinical evidence due to the challenges of studying medical cannabis through randomised controlled trials. In order to develop the current evidence base, the importance of incorporating real-world data (RWD) to assess the effectiveness and efficacy of medical cannabis has gradually become recognised. The current paper provides a detailed outline of Project Twenty21 (T21), the UK's first medical cannabis registry, launched in August 2020. We provide the rationale for T21 and describe the methodology before reporting the characteristics of the 'first patients' enrolled in the registry. We describe the health status of all patients enrolled into the project during its first 7 months of operation and the sociodemographic characteristics and primary presenting conditions for these patients, as well as details of the medical cannabis prescribed to these individuals. By 12th March 2021, 678 people had been enrolled into T21; the majority (64%) were male and their average age was 38.7 years (range = 18-80). The most commonly reported primary conditions were chronic pain (55.6%) and anxiety disorders (32.0%) and they reported high levels of multi-morbidity, including high rates of insomnia and depression. We also present preliminary evidence from 75 patients followed up after 3 months indicating that receipt of legal, prescribed cannabis was associated with a significant increase in self-reported health, assessed using the visual analogue scale of the EQ-5D-5L (Cohen's d = .77, 95% CI = .51-1.03). Our initial findings complement reports from other large-scale databases globally, indicating that the current RWD is building up a pattern of evidence. With many clinicians demanding better and faster evidence to inform their decisions around prescribing medical cannabis, the current and future results of T21 will expand the existing evidence base on the effectiveness of cannabis-based medical products (CBMPs).

Increasing Access to Safe Medical Cannabis: Establishment of a Medical Cannabis Program in a Safety-Net Academic Medical Center

Despite numerous challenges, Montefiore Medical Center in New York City implemented a program aimed at providing comprehensive, evidence-based medical cannabis certifications to patients, including those who have been historically disenfranchised, and shares insights from five years of operation.

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.

First-Year Trajectories of Medical Cannabis Use Among Adults Taking Opioids for Chronic Pain: An Observational Cohort Study

OBJECTIVE

To describe first-year trajectories of medical cannabis use and identify characteristics associated with patterns of use in a cohort of adults using opioids for chronic pain.

DESIGN

Latent class trajectory analysis of a prospective cohort study using data on the 14-day frequency of medical cannabis use.

SETTING

A large academic medical center and four medical cannabis dispensaries in the New York City metropolitan area.

SUBJECTS

Adults with chronic pain using opioids and newly certified for medical cannabis in New York between 2018 and 2020.

METHODS

Using latent class trajectory analysis, we identified clusters of participants based on the 14-day frequency of medical cannabis use. We used logistic regression to determine factors associated with cluster membership, including sociodemographic characteristics, pain, substance use, and mental health symptoms.

RESULTS

Among 99 participants, the mean age was 53 years; 62% were women, and 52% were White. We identified three clusters of medical cannabis use: infrequent use (n = 30, mean use = 1.5 days/14-day period), occasional use (n = 28, mean = 5.7 days/14-day period), and frequent use (n = 41, mean = 12.1 days/14-day period). Within clusters, use patterns did not vary significantly over 52 weeks. Differences were observed in two sociodemographic variables: Frequent (vs infrequent) use was associated with non-Hispanic White race/ethnicity (adjusted odds ratio 4.54, 95% confidence interval 1.49-14.29), while occasional (vs infrequent) use was associated with employment (adjusted odds ratio 13.84, 95% confidence interval 1.21-158.74).

CONCLUSIONS

Three clusters of medical cannabis use patterns emerged and were stable over time. Results suggest that structural factors related to race/ethnicity and employment may be major drivers of medical cannabis use, even among adults certified for its use.

Real World Evidence in Medical Cannabis Research

BACKGROUND

Whilst access to cannabis-based medicinal products (CBMPs) has increased globally subject to relaxation of scheduling laws globally, one of the main barriers to appropriate patient access remains a paucity of high-quality evidence surrounding their clinical effects.

DISCUSSION

Whilst randomised controlled trials (RCTs) remain the gold-standard for clinical evaluation, there are notable barriers to their implementation. Development of CBMPs requires novel approaches of evidence collection to address these challenges. Real world evidence (RWE) presents a solution to not only both provide immediate impact on clinical care, but also inform well-conducted RCTs. RWE is defined as evidence derived from health data sourced from non-interventional studies, registries, electronic health records and insurance data. Currently it is used mostly to monitor post-approval safety requirements allowing for long-term pharmacovigilance. However, RWE has the potential to be used in conjunction or as an extension to RCTs to both broaden and streamline the process of evidence generation.

CONCLUSION

Novel approaches of data collection and analysis will be integral to improving clinical evidence on CBMPs. RWE can be used in conjunction or as an extension to RCTs to increase the speed of evidence generation, as well as reduce costs. Currently, there is an abundance of potential data however, whilst a number of platforms now exist to capture real world data it is important the right tools and analysis are utilised to unlock potential insights from these.

Comparing medical cannabis use in 5 US states: a retrospective database study

Background

US states have been adopting their own medical cannabis laws since 1996. There is substantial variability in the medical cannabis programs between states, and these differences have not been thoroughly investigated in the literature. The objective of the study was to compare medical cannabis patient characteristics across five states to identify differences potentially caused by differing policies surrounding condition eligibility.

Methods

We conducted secondary analyses following a retrospective study of a registry database with data from 33 medical cannabis evaluation clinics in the US, owned and operated by CB2 Insights. This study narrowed the dataset to include patients from five states with the largest samples: Massachusetts (n = 27,892), Colorado (n = 16,434), Maine (n = 4591), Connecticut (n = 2643), and Maryland (n = 2403) to conduct an in-depth study of the characteristics of patients accessing medical cannabis in these states, including analysis of variance to compare average ages and number of conditions and chi-squared tests to compare proportions of patient characteristics between states.

Results

Average ages varied between the states, with the youngest average in Connecticut (42.2) and the oldest in Massachusetts (47.0). Males represented approximately 60% of the patients with data on gender in each state. The majority of patients in each state had cannabis experience prior to seeking medical certification. Primary medical conditions varied for each state, with chronic pain, anxiety, and back and neck problems topping the list in varying orders for Massachusetts, Maine, and Maryland. Colorado had 78.7% of patients report chronic pain as their primary condition, and 70.4% of patients in Connecticut reported post-traumatic stress disorder as their primary medical condition.

Conclusion

This study demonstrated the significant impact that policy has on patients’ access to medical cannabis in Massachusetts, Colorado, Maine, Connecticut, and Maryland utilizing real-world data. It highlights how qualifications differ between the five states and brings into question the routes through which patients in states with stricter regulations surrounding eligible conditions choose to seek treatment with cannabis. These patients may turn to alternative treatments, or to the illicit or recreational cannabis markets, where permitted.

Supplementary Information

The online version contains supplementary material available at 10.1186/s42238-021-00075-z.

Vanishing lung syndrome: a consequence of mixed tobacco and marijuana use

Idiopathic giant bullous emphysema or vanishing lung syndrome (VLS) is a rare, chronic radiological diagnosis characterised by giant emphysematous bullae located primarily in the upper lobes of the lungs. This highly morbid phenotype of chronic obstructive pulmonary disease leads to severe progressive dyspnoea and significant disability. Here, we describe a 48-year-old man with a history significant for long-term tobacco and cannabis smoking, who is found to have VLS. We present a review of recent findings on the association between VLS and the additive effect of marijuana and tobacco.

Current controversies in medical cannabis: Recent developments in human clinical applications and potential therapeutics

Knowledge about the therapeutic potential of medical cannabis has greatly improved over the past decade, with an ever-increasing range of developments in human clinical applications. A growing body of scientific evidence supports the use of medical cannabis products for some therapeutic indications, whilst for others, the evidence base remains disputed. For this narrative review, we incorporate areas where the current evidence base is substantial, such as intractable childhood epilepsy and multiple sclerosis, as well as areas where the evidence is still controversial, such as PTSD and anxiety. We provide a high-level summary of current developments using findings from recent major reviews, as well as real world evidence (RWE), including global database registries and other patient reported outcomes (PROs). On the one hand, our strongest empirical data supports the use of cannabis-based medicinal products (CBMPs) for conditions with relatively small patient numbers. Yet on the other hand, the conditions, where the highest patient numbers present, often have debatable clinical evidence but good RWE, incorporating PROs of 1000s of patients. The discord between PROs and the respective strength of the evidence from randomised controlled trials (RCTs) highlights the urgent need for further research. The scientific literature examining the efficacy of medical cannabis for many conditions is still developing, whilst large numbers of patients globally have been successfully using medical cannabis to treat a broad range of conditions. We conclude on the importance of systematically developing RWE databases to supplement RCTs and to bridge the current evidence gaps.