U.S. Trends in Registration for Medical Cannabis and Reasons for Use From 2016 to 2020 : An Observational Study

Cannabis use in Parkinson's disease: Patient access to medical cannabis and physician perspective on product safety

The rate of medical cannabis use has increased in parallel with the number of states legalizing its use. Parkinson's disease (PD) patients are of particular concern due to their higher cannabis use rate than in the general US population (25-40 % PD patient cannabis users vs. ∼18 % in the general population), as well as their susceptibility to environmental contaminants in cannabis, including pesticides, toxic elements, solvents, microbes, and mycotoxins. In order to address the complex nature of this industry, we examined the changes in PD-related qualifying conditions in the U.S. from 2019 to 2023. We also conducted an online survey to gain insight into the knowledge, risk perceptions, and opinions regarding medical cannabis and contamination issues from physicians who treated PD patients. The number of states including PD-related qualifying conditions increased over the past 5 years from 28 to 36 states. These conditions included PD (increasing from 14 to 16 states), muscle spasms (14 to 24), anxiety (1 to 5), and pain (17 to 35). State-by-state comparisons revealed high variability in the language used to describe the different qualifying conditions. Online surveys were sent out to 45 neurologists and movement disorder specialists who primarily treated PD patients. The response rate was 44 % from nine states (AZ, CA, FL, MA, MN, WI, PA, IL, and NM). When asked if they were aware of any contaminants in cannabis products, we found that 65 % of the physicians were unaware of any contaminants commonly found in cannabis and only 25 %, 15 %, and 15 % of them were aware of pesticide, toxic element, and solvent contaminants, respectively. In their free-text opinion response on the health impact of cannabis-borne contaminants, "long-term effect" (35 %) and "comorbidities and PD prognosis" (40 %) were identified as the two most common themes. These results point to the need for further regulatory deliberation regarding risks and susceptibility to cannabis contaminants. Additionally, education is needed to inform physicians on cannabis safety issues. Further research will identify the implementation strategies to reduce contaminant exposure and protect patient health.

Access to care for patients with chronic pain receiving prescription opioids, cannabis, or other treatments

Changes in chronic noncancer pain treatment have led to decreases in prescribing of opioids and increases in the availability of medical cannabis, despite its federal prohibition. Patients may face barriers to establishing new care with a physician based on use of these treatments. We compared physician willingness to accept patients based on prescription opioid, cannabis, or other pain treatment use. This study of 36 states and Washington, DC, with active medical cannabis programs surveyed physicians who treat patients with chronic noncancer pain between July 13 and August 4, 2023. Of 1000 physician respondents (34.5% female, 63.2% White, 78.1% primary care), 852 reported accepting new patients with chronic pain. Among those accepting new patients with chronic pain, more physicians reported that they would not accept new patients taking prescription opioids (20.0%) or cannabis (12.7%) than those taking nonopioid prescription analgesics (0.1%). In contrast, 68.1% reported willingness to accept new patients using prescribed opioids on a daily basis. For cannabis, physicians were more likely to accept new patients accessing cannabis through medical programs (81.6%) than from other sources (60.2%). Access to care for persons with chronic noncancer pain appears to be the most restricted among those taking prescription opioids, although patients taking cannabis may also encounter reduced access.

Impact of year-long cannabis use for medical symptoms on brain activation during cognitive processes

Importance

Cannabis is increasingly being used to treat medical symptoms, but the effects of cannabis use on brain function in those using cannabis for these symptoms is not known.

Objective

To test whether brain activation during working memory, reward, and inhibitory control tasks, areas of cognition impacted by cannabis, showed increases following one year of cannabis use for medical symptoms.

Design

This observational cohort study took place from July 2017 to July 2020 and is reported on in 2024.

Setting

Participants were from the greater Boston area.

Participants

Participants were recruited as part of a clinical trial based on seeking medical cannabis cards for anxiety, depression, pain, or sleep disorders, and were between 18 and 65 years. Exclusion criteria were daily cannabis use and cannabis use disorder at baseline.

Main Outcomes and Measures

Outcomes were whole brain functional activation during tasks involving working memory, reward and inhibitory control at baseline and after one year of cannabis use.

Results

Imaging was collected in participants before and one year after obtaining medical cannabis cards; 57 at baseline (38 female [66.7%]; mean [SD] age, 38.0 [14.6] years) at baseline, and 54 at one-year (37 female [68.5%]; mean [SD] age, 38.7 [14.3] years). Imaging was also collected in 32 healthy control participants (22 female [68.8%]; mean [SD] age, 33.8 [11.8] years) at baseline. In all groups and at both time points, functional imaging revealed canonical activations of the probed cognitive processes. No statistically significant difference in brain activation between the two timepoints (baseline and one-year) in those with medical cannabis cards and no association of changes in cannabis use frequency with brain activation were found.

Conclusions and Relevance

Findings suggest that adults do not show significant neural effects in the areas of cognition of working memory, reward, and inhibitory control after one year of cannabis use for medical symptoms. The results warrant further studies that probe effects of cannabis at higher doses, with greater frequency, in younger age groups, and with larger, more diverse cohorts.

Trial Registration

NCT03224468, https://clinicaltrials.gov/.

Review of the Use of Medicinal Cannabis Products in Palliative Care

In this review, we discuss the potential role of cannabis and cannabinoids in the management of cancer-related symptoms. There is limited evidence demonstrating the effectiveness of cannabis-based products in treating cancer-related pain and gastrointestinal symptoms such as nausea, vomiting, and loss of appetite. Regarding the role of cannabis-based products in the treatment of insomnia and mood disorders, most studies looked at these symptoms as secondary outcomes with mixed results. Cannabis-based products have adverse effects, ranging from neuropsychiatric to systemic effects to potential drug interactions.

Neuromodulation for Cannabis Use: A Scoping Review

This scoping review explores the use of neuromodulation techniques in individuals with cannabis use. Our goal was to determine whether cannabis use alters cortical excitation and inhibition in the context of neuromodulation and to determine whether neuromodulation affects craving and cannabis use patterns. A systematic search was conducted using PubMed, OVID Medline, and PsycINFO from inception to 20 December 2022. Our review identified ten relevant studies, eight of which used Transcranial Magnetic Stimulation (TMS), while two employed Transcranial Direct Current Stimulation (tDCS). Findings from TMS studies suggest that cannabis users exhibit altered cortical inhibition, with decreased short interval intracortical inhibition (SICI) compared to non-users. Single sessions of rTMS did not have any impact on cannabis craving. By contrast, two studies found that multiple sessions of rTMS reduced cannabis use, but these changes did not meet the threshold for statistical significance and both studies were limited by small sample sizes. The two included tDCS studies found contradictory results, with one showing reduced cannabis craving with active treatment and another showing no effect of active treatment on craving compared to sham. Future studies should further explore the effects of multiple treatment sessions and different neuromodulation modalities.

Trends in U.S. Medical Cannabis Registrations, Authorizing Clinicians, and Reasons for Use From 2020 to 2022

BACKGROUND

As medical cannabis availability increases, up-to-date trends in medical cannabis licensure can inform clinical policy and care.

OBJECTIVE

To describe current trends in medical cannabis licensure in the United States.

DESIGN

Ecological study with repeated measures.

SETTING

Publicly available state registry data from 2020 to 2022.

PARTICIPANTS

People with medical cannabis licenses and clinicians authorizing cannabis licenses in the United States.

MEASUREMENTS

Total patient volume and prevalence per 10 000 persons in the total population, symptoms or conditions qualifying patients for licensure (that is, patient-reported qualifying conditions), and number of authorizing clinicians.

RESULTS

In 2022, of 39 jurisdictions allowing medical cannabis use, 34 reported patient numbers, 19 reported patient-reported qualifying conditions, and 29 reported authorizing clinician numbers. Enrolled patients increased 33.3% from 2020 (3 099 096) to 2022 (4 132 098), with a corresponding 23.0% increase in the population prevalence of patients (175.0 per 10 000 in 2020 to 215.2 per 10 000 in 2022). However, 13 of 15 jurisdictions with nonmedical adult-use laws had decreased enrollment from 2020 to 2022. The proportion of patient-reported qualifying conditions with substantial or conclusive evidence of therapeutic value decreased from 70.4% (2020) to 53.8% (2022). Chronic pain was the most common patient-reported qualifying condition in 2022 (48.4%), followed by anxiety (14.2%) and posttraumatic stress disorder (13.0%). In 2022, the United States had 29 500 authorizing clinicians (7.7 per 1000 patients), 53.5% of whom were physicians. The most common specialties reported were internal or family medicine (63.4%), physical medicine and rehabilitation (9.1%), and anesthesia or pain (7.9%).

LIMITATION

Missing data (for example, from California), descriptive analysis, lack of information on individual use patterns, and changing evidence base.

CONCLUSION

Enrollment in medical cannabis programs increased overall but generally decreased in jurisdictions with nonmedical adult-use laws. Use for conditions or symptoms without a strong evidence basis continues to increase. Given these trends, more research is needed to better understand the risks and benefits of medical cannabis.

PRIMARY FUNDING SOURCE

National Institute on Drug Abuse of the National Institutes of Health.

Polypharmacy, over-the-counter medications, and aromatase inhibitor adherence in early-stage breast cancer

PURPOSE

Polypharmacy is associated with negative health outcomes and decreased medication adherence. Polypharmacy is common in cancer populations, but few studies have evaluated the relationship between polypharmacy and aromatase inhibitor (AI) adherence. No studies have evaluated the relationship between over-the-counter (OTC) supplements and AI adherence. Our primary hypothesis was that polypharmacy would be associated with increased risk of premature AI discontinuation.

METHODS

This exploratory analysis used data from the Exemestane and Letrozole Pharmacogenetics (ELPh) trial, a prospective, multicenter, randomized controlled trial that enrolled participants from 2005 to 2009. Included patients were female, postmenopausal, with stage 0-III breast cancer, who had completed indicated chemotherapy, surgery, and radiation. Participants were randomized to adjuvant exemestane or letrozole and completed serial clinical examinations and questionnaires for two years. Concomitant medication data were collected prospectively. Cox proportion models were used for statistical analysis of the relationship between polypharmacy, OTCs, medication class, and AI adherence.

RESULTS

In the 490 analyzed participants, use of any prescription medications at baseline was associated with decreased risk of premature AI discontinuation (HR 0.56, p = 0.02). Use of selective serotonin reuptake inhibitors (SSRIs) or selective serotonin and norepinephrine reuptake inhibitors (SNRIs) at baseline was associated with decreased risk of premature AI discontinuation (HR 0.67, p = 0.04). Use of any OTCs was not associated with AI discontinuation.

CONCLUSION

Baseline use of prescription medications but not OTCs was associated with increased AI persistence. Future research is needed to understand how this can be utilized to promote AI adherence.

A national study of clinical discussions about cannabis use among Veteran patients prescribed opioids

BACKGROUND

The Veterans Health Administration tracks urine drug tests (UDTs) among patients on long-term opioid therapy (LTOT) and recommends discussing the health effects of cannabis use.

OBJECTIVE

To determine the occurrence of cannabis-related discussions between providers and patients on LTOT during six months following UDT positive for cannabis, and examine factors associated with documenting cannabis use.

DESIGN

We identified patients prescribed LTOT with a UDT positive for cannabis in 2019. We developed a text-processing tool to extract discussions around cannabis use from their charts.

SUBJECTS

Twelve thousand seventy patients were included. Chart review was conducted on a random sample of 1,946 patients.

MAIN MEASURES

The presence of a cannabis term in the chart suggesting documented cannabis use or cannabis-related discussions. Content of those discussions was extracted in a subset of patients. Logistic regression was used to examine the association between patient factors, including state of residence legal status, with documentation of cannabis use.

KEY RESULTS

Among the 12,070 patients, 65.8% (N = 7,948) had a cannabis term, whereas 34.1% (N = 4,122) of patients lacked a cannabis term, suggesting that no documentation of cannabis use or discussion between provider and patient took place. Among the subset of patients who had a discussion documented, 47% related to cannabis use for medical reasons, 35% related to a discussion of VA policy or legal issues, and 17% related to a discussion specific to medical risks or harm reduction strategies. In adjusted analyses, residents of states with legalized recreational cannabis were less likely to have any cannabis-related discussion compared to patients in non-legal states [OR 0.73, 95% CI 0.64-0.82].

CONCLUSIONS

One-third of LTOT patients did not have documentation of cannabis use in the chart in the 6 months following a positive UDT for cannabis. Discussions related to the medical risks of cannabis use or harm reduction strategies were uncommon.

Medicinal cannabis use among young adults during California's transition from legalized medical use to adult-use: a longitudinal analysis

Background: In 2016, California transitioned from legalized medical cannabis use to adult-use. Little is known about how this policy change affected medicinal cannabis use among young adults.Objectives: To identify longitudinal groups of medicinal cannabis users and concurrent changes in health- and cannabis use-related characteristics among young adults in Los Angeles between 2014 and 2021.Methods: Cannabis users (210 patients and 156 non-patients; 34% female; ages 18-26 at baseline) were surveyed annually across six waves. Longitudinal latent class analysis derived groups from two factors - cannabis patient status and self-reported medicinal use. Trajectories of health symptoms, cannabis use motives, and cannabis use (daily/near daily use, concentrate use, and problematic use) were estimated across groups.Results: Three longitudinal latent classes emerged: Recreational Users (39.3%) - low self-reported medicinal use and low-to-decreasing patient status; Recreational Patients (40.4%) - low self-reported medicinal use and high-to-decreasing patient status; Medicinal Patients (20.3%) - high self-reported medicinal use and high-to-decreasing patient status. At baseline, Medicinal Patients had higher levels of physical health symptoms and motives than recreational groups (p < .05); both patient groups reported higher level of daily/near daily and concentrate use (p < .01). Over time, mental health symptoms increased in recreational groups (p < .05) and problematic cannabis use increased among Recreational Patients (p < .01).Conclusions: During the transition to legalized adult-use, patterns of medicinal cannabis use varied among young adults. Clinicians should monitor increases in mental health symptoms and cannabis-related problems among young adults who report recreational - but not medicinal - cannabis use.

A semi-naturalistic open-label study examining the effect of prescribed medical cannabis use on simulated driving performance

BACKGROUND

Despite increasing medical cannabis use, research has yet to establish whether and to what extent products containing delta-9-tetrahydrocannabinol (THC) impact driving performance among patients. Stable doses of prescribed cannabinoid products during long-term treatment may alleviate clinical symptoms affecting cognitive and psychomotor performance.

AIM

To examine the effects of open-label prescribed medical cannabis use on simulated driving performance among patients.

METHODS

In a semi-naturalistic laboratory study, 40 adults (55% male) aged between 23 and 80 years, consumed their own prescribed medical cannabis product. Driving performance outcomes including standard deviation of lateral position (SDLP), the standard deviation of speed (SDS), mean speed and steering variability were evaluated using the Forum8 driving simulator at baseline (pre-dosing), 2.5 h and 5 -h (post-dosing). Perceived driving effort (PDE) was self-reported after each drive. Oral fluid and whole blood samples were collected at multiple timepoints and analysed for THC via liquid chromatography-mass spectrometry.

RESULTS

A significant main effect of time was observed for mean speed (p = 0.014) and PDE (p = 0.020), with patients displaying modest stabilisation of vehicle control, increased adherence to speed limits and reductions in PDE post-dosing, relative to baseline. SDLP (p = 0.015) and PDE (p = 0.043) were elevated for those who consumed oil relative to flower-based products. Detectable THC concentrations were observed in oral fluid at 6-h post-dosing (range = 0-24 ng/mL).

CONCLUSIONS

This semi-naturalistic study suggests that the consumption of medical cannabis containing THC (1.13-39.18 mg/dose) has a negligible impact on driving performance when used as prescribed.

The Association of Cannabis Use After Discharge From Surgery With Opioid Consumption and Patient-reported Outcomes

OBJECTIVE

To compare outcomes of patients using versus not using cannabis as a treatment for pain after discharge from surgery.

BACKGROUND

Cannabis is increasingly available and is often taken by patients to relieve pain. However, it is unclear whether cannabis use for pain after surgery impacts opioid consumption and postoperative outcomes.

METHODS

Using Michigan Surgical Quality Collaborative registry data at 69 hospitals, we analyzed a cohort of patients undergoing 16 procedure types between January 1, 2021, and October 31, 2021. The key exposure was cannabis use for pain after surgery. Outcomes included postdischarge opioid consumption (primary) and patient-reported outcomes of pain, satisfaction, quality of life, and regret to undergo surgery (secondary).

RESULTS

Of 11,314 included patients (58% females, mean age: 55.1 years), 581 (5.1%) reported using cannabis to treat pain after surgery. In adjusted models, patients who used cannabis consumed an additional 1.0 (95% CI: 0.4-1.5) opioid pills after surgery. Patients who used cannabis were more likely to report moderate-to-severe surgical site pain at 1 week (adjusted odds ratio: 1.7, 95% CIL 1.4-2.1) and 1 month (adjusted odds ratio: 2.1, 95% CI: 1.7-2.7) after surgery. Patients who used cannabis were less likely to endorse high satisfaction (72.1% vs 82.6%), best quality of life (46.7% vs 63.0%), and no regret (87.6% vs 92.7%) (all P < 0.001).

CONCLUSIONS

Patient-reported cannabis use, to treat postoperative pain, was associated with increased opioid consumption after discharge from surgery that was of clinically insignificant amounts, but worse pain and other postoperative patient-reported outcomes.

Young Adult Depression and Cannabis Use: Associations Before and After Recreational Legalization

INTRODUCTION

The co-occurrence of depression with cannabis use worsens both mood and substance use disorder outcomes, with young adults particularly at risk of co-occurrence. This research investigates whether the association of state-level prevalence rates of young adult (age 18-25) depression and cannabis use in the U.S. changed following enactment of recreational (adult use) cannabis legalization between 2008 and 2019.

METHODS

Annual, state prevalence data on past-year major depressive episode (hereafter, depression) and past-month cannabis use were extracted from the National Survey on Drug Use and Health (N=600 state-year observations). Moderated regression models tested whether the association of depression with cannabis use differed before versus after recreational legalization by comparing prevalence rates of depression and cannabis use in states that enacted recreational legalization to those that did not, while fixing state, year, and medical legalization effects. Data were accessed and analyzed in 2023.

RESULTS

Prevalence rates of both depression and cannabis use increased throughout the study period. The positive statistical effect of depression on cannabis use more than doubled in magnitude after legalization (β=0.564, 95% CI=0.291, 0.838) as compared to before (β=0.229, 95% CI=0.049, 0.409), representing a significant change (β=0.335, 95% CI=0.093, 0.577).

CONCLUSIONS

These results suggest that the association between prevalence rates of young adult depression and cannabis use strengthened following recreational legalization in the U.S. This is potentially due to increases in cannabis accessibility and the acceptance of the health benefits of cannabis, which may enhance the use of cannabis as a coping mechanism among young adults with depression.

Marijuana and endoscopy: the effects of marijuana on sedation

BACKGROUND AND AIMS

Marijuana usage has increased significantly as it has become more readily available and legal, either recreationally or medicinally, in many states. It has been postulated that marijuana usage increases the amount of sedation required for procedures. However, there are minimal data defining this relationship. We aimed to establish the relationship between marijuana usage and the amount of sedation used during endoscopy.

METHODS

This was a single-institution prospective study of patients undergoing outpatient endoscopy (both monitored anesthesia care [MAC] and moderate sedation) at the Oklahoma City Veterans Affairs Medical Center. Marijuana usage was assessed by a voluntary de-identified pre-endoscopy survey. Information regarding sedation used, endoscopy outcomes, demographics, comorbidities, medical history, and medications used was extracted from the medical record. A univariate and stratified analysis of alcohol usage was performed. A P value of <.05 was considered to be significant.

RESULTS

A total of 976 patients were analyzed; 21.5% of them endorsed marijuana usage (210/976). Marijuana users were found to be younger (P = .0002), leaner (P < .0001), and less likely to have diabetes (P = .002), obstructive sleep apnea (P = .0002), and hypertension (P = .04). They were also more likely to smoke (P < .0001) and vape (P < .0001). Marijuana usage was associated with a higher requirement of sedation (fentanyl [P = .003], midazolam [P = .05], propofol [P = .02]) and higher use of adjunct sedation (diphenhydramine in moderate sedation [P = .0003]). Further multivariate analyses were performed to control for possible confounders. Marijuana usage was still deemed to be an independent predictor for high propofol use among MAC cases (odds ratio [OR], 1.77; 95% confidence interval [CI], 1.00-3.12). Likewise, marijuana usage was found to be an independent predictor for high midazolam use (OR, 1.57; 95% CI, 1.02-2.42) and high fentanyl use (OR, 1.54; 95% CI, 0.98-2.38), but failed to reach statistical significance in the fentanyl group.

CONCLUSIONS

Marijuana use is associated with a significantly higher amount of sedation along with a significantly higher usage of other adjunct sedatives. A patient's marijuana history should be considered when determining the methods of sedation to be used for endoscopy.

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.

Dispensaries and Medical Marijuana Certifications and Indications: Unveiling the Geographic Connections in Pennsylvania, USA

Introduction

Pennsylvania opened its first medical marijuana (MMJ) dispensary in 2018. Qualifying conditions include six conditions determined to have no or insufficient evidence to support or refute MMJ effectiveness. We conducted a study to describe MMJ dispensary access in Pennsylvania and to determine whether dispensary proximity was associated with MMJ certifications and community demographics.

Methods

Using data from the Pennsylvania Department of Health, we geocoded MMJ dispensary locations and linked them to US Census Bureau data. We created dispensary access measures from the population-weighted centroid of Zip Code Tabulation Areas (ZCTAs): distance to nearest dispensary and density of dispensaries within a 15-min drive. We evaluated associations between dispensary access and the proportion of adults who received MMJ certification and the proportion of certifications for low evidence conditions (amyotrophic lateral sclerosis, epilepsy, glaucoma, Huntington's disease, opioid use disorder, and Parkinson's disease) using negative binomial modeling, adjusting for community features. To evaluate associations racial and ethnic composition of communities and distance to nearest dispensary, we used logistic regression to estimate the odds ratios (OR) and 95% confidence intervals (CI), adjusting for median income.

Results

Distance and density of MMJ dispensaries were associated with the proportion of the ZCTA population certified and the proportion of certifications for insufficient evidence conditions. Compared to ZCTAs with no dispensary within 15 min, the proportion of adults certified increased by up to 31% and the proportion of certifications for insufficient evidence decreased by up to 22% for ZCTAs with two dispensaries. From 2018 to 2021, the odds of being within five miles of a dispensary was up to 20 times higher in ZCTAs with the highest proportions of individuals who were not White (2019: OR: 20.14, CI: 10.7-37.8) and more than double in ZCTAs with the highest proportion of Hispanic individuals (2018: OR: 2.81, CI: 1.51-5.24), compared to ZCTAs with the lowest proportions.

Conclusions

Greater dispensary access was associated with the proportions of certified residents and certifications for low evidence conditions. Whether these patterns are due to differences in accessibility or demand is unknown. Associations between community demographics and dispensary proximity may indicate MMJ access differences.

Relationship Between Nociplastic Pain Involvement and Medication Use, Symptom Relief, and Adverse Effects Among People Using Medical Cannabis for Chronic Pain

OBJECTIVES

Cannabis is increasingly being used for chronic pain management, but cannabis' effects remain poorly characterized in chronic nociplastic pain (NPP), which is posited to be caused by disturbances in nervous system pain processing. In this cross-sectional study (n=1213), we used the 2011 Fibromyalgia (FM) Survey Criteria as a surrogate measure for degree of NPP among individuals using medical cannabis for chronic pain.

METHODS

Using a quartile-split, we investigated associations between the degree of NPP and medication use, cannabis use characteristics, and symptom relief. Continuous variables were assessed using one-way analysis of variance and categorical variables with Pearson χ 2 test and binomial logistic regression for calculation of odds ratios.

RESULTS

Participants were predominately female (59%), with a mean ± SD age of 49.4±13.6 years. Higher FM scores were associated with less self-reported improvement in pain and health since initiating medical cannabis use, as well as more cannabis-related side effects. Paradoxically, higher FM scores were also associated with higher usage of concomitant medication use (including opioids and benzodiazepines) but also with substituting cannabis for significantly more medication classes, including opioids and benzodiazepines.

DISCUSSION

This article presents evidence that individuals in higher NPP quartiles have higher analgesic intake, higher odds of substituting cannabis for medications, higher side effect burden, and lower therapeutic effect from cannabis. These seemingly contradictory findings may reflect higher symptom burden, polypharmacy at baseline, or that NPP may be challenging to treat with cannabis. Further research is necessary to further explain cannabinoid effects in NPP.

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.

Legal and Regulatory Aspects of Medical Cannabis in the United States

Federal and state laws in the United States governing the use of cannabis are rapidly evolving. Under federal law, marijuana and its derivatives remain schedule I, defined as substances having no currently accepted medical use and a high potential for abuse. Hemp and its derivatives, in contrast, have been removed from schedule I. At the state level, a majority of states have passed laws legalizing cannabis in some form, although these laws vary from state to state in terms of the extent to which use is permitted, approved medical uses, and the types of regulation placed on commercial activity and quality control. This inconsistency has contributed to uncertainty among medical providers and their patients. In this review, we provide a brief account of the evolution and current state of federal and state laws and regulatory agencies involved in overseeing medical cannabis use in the United States.

Association of cannabis use with patient-reported pain measures among adults with chronic pain in US states with medical cannabis programs

INTRODUCTION

Most Americans live in a state that has legalized cannabis as a medical treatment for pain, but it is unclear how chronic pain intensity relates to cannabis use. Our objective was to examine the association between patient-reported pain measures and cannabis among adults with chronic pain.

METHODS

This cross-sectional study of a representative sample of adults reporting chronic non-cancer pain in 36 states and DC with active medical cannabis programs from March to April 2022 assessed cannabis use for chronic pain, categorized as active (within 30 days), past (>31 days), or never use (referent). Measures were pain intensity (primary) and interference, Widespread Pain Index, and number of chronic pain diagnoses.

RESULTS

Among 1628 participants (57% female, 69% white), 352 (22%) actively used cannabis to treat chronic pain, 137 (8%) reported past cannabis use, and 1139 (70%) never used cannabis. In adjusted models, active cannabis use was associated with higher scores for pain intensity (score difference 1.03, 95% CI 0.05 to 2.02) and pain interference (score difference 1.82, 95% CI 0.99 to 2.65) compared with never use. Persons who actively used cannabis had higher Widespread Pain Index scores (score difference 0.56, 95% CI 0.26 to 0.86) and more chronic pain diagnoses (difference 0.45, 95% CI 0.06 to 0.83).

CONCLUSION

People with chronic non-cancer pain who used cannabis for pain reported non-clinically meaningful worse pain measures and greater burden of chronic pain conditions than their counterparts who never used cannabis. Alternatively, those with worse pain and greater burden of pain appear more likely to use cannabis.

Analysis of Dispensing and Utilization Patterns of Medical Cannabis Products in State Licensed Cannabis Dispensaries

Background: To understand real-world dispensing and utilization patterns of medical cannabis (MC) and its financial impact on patients, we analyzed the database of a cannabis company licensed in New York state. Objectives: To evaluate the tetrahydrocannabinol (THC)/cannabidiol (CBD) dose ratios, association of various medical conditions to THC/CBD dose, and the cost of products in registered patients receiving MC from four licensed state dispensaries. Design: Retrospective analysis conducted on anonymized data between January 1, 2016 and December 31, 2020 listing 422,201 dispensed products from 32,845 individuals aged 18 years and older. Setting/Subjects: Adult patients with medical certification for cannabis use in New York, USA. Measurements: The database included patient's age, gender, qualifying medical condition, type and dose of product, medication directions, and amount of product dispensed. Results: Findings showed a median age of 53 years with 52% of patients female. Males were found to use more products than females (1.06:1). Pain (85%) was the most common medical condition and inhalation (57%) the most common route except when used for cancer-directed treatment and neurological conditions. Individuals received a median of six prescriptions costing a median of $50/product. Average THC:CBD ratios were 28:0.5 mg/day and 12:0.25 mg/dose. Neurological conditions demonstrated the highest average cost [mean (95% confidence interval {CI}): $73 ($71-$75)] and average CBD/dose per product [mean (95% CI): 5.89 (5.38-6.40)]. Individuals with a history of substance use disorder utilizing MC as an alternative substance displayed the highest average THC/dose [mean (95% CI): 14.25 (13.36-15.14)]. Conclusion: MC was utilized for various medical conditions with variability in THC:CBD ratio seen depending on the condition. Cost variation was also observed based on the individual's medical condition.

Chronic pain, cannabis legalisation, and cannabis use disorder among patients in the US Veterans Health Administration system, 2005 to 2019: a repeated, cross-sectional study

BACKGROUND

Cannabis use disorder is associated with considerable comorbidity and impairment in functioning, and prevalence is increasing among adults with chronic pain. We aimed to assess the effect of introduction of medical cannabis laws (MCL) and recreational cannabis laws (RCL) on the increase in cannabis use disorder among patients in the US Veterans Health Administration (VHA).

METHODS

Data from patients with one or more primary care, emergency, or mental health visit to the VHA in 2005-19 were analysed using 15 repeated cross-sectional VHA electronic health record datasets (ie, one dataset per year). Patients in hospice or palliative care were excluded. Patients were stratified as having chronic pain or not using an American Pain Society taxonomy of painful medical conditions. We used staggered-adoption difference-in-difference analyses to estimate the role of MCL and RCL enactment in the increases in prevalence of diagnosed cannabis use disorder and associations with presence of chronic pain, accounting for the year that state laws were enacted. We did this by fitting a linear binomial regression model stratified by pain, with time-varying cannabis law status, fixed effects for state, categorical year, time-varying state-level sociodemographic covariates, and patient covariates (age group [18-34 years, 35-64 years, and 65-75 years], sex, and race and ethnicity).

FINDINGS

Between 2005 and 2019, 3 234 382-4 579 994 patients were included per year. Among patients without pain in 2005, 5·1% were female, mean age was 58·3 (SD 12·6) years, and 75·7%, 15·6%, and 3·6% were White, Black, and Hispanic or Latino, respectively. In 2019, 9·3% were female, mean age was 56·7 (SD 15·2) years, and 68·1%, 18·2%, and 6·5% were White, Black, and Hispanic or Latino, respectively. Among patients with pain in 2005, 7·1% were female, mean age was 57·2 (SD 11·4) years, and 74·0%, 17·8%, and 3·9% were White, Black, and Hispanic or Latino, respectively. In 2019, 12·4% were female, mean age was 57·2 (SD 13·8) years, and 65·3%, 21·9%, and 7·0% were White, Black, and Hispanic or Latino, respectively. Among patients with chronic pain, enacting MCL led to a 0·135% (95% CI 0·118-0·153) absolute increase in cannabis use disorder prevalence, with 8·4% of the total increase in MCL-enacting states attributable to MCL. Enacting RCL led to a 0·188% (0·160-0·217) absolute increase in cannabis use disorder prevalence, with 11·5% of the total increase in RCL-enacting states attributable to RCL. In patients without chronic pain, enacting MCL and RCL led to smaller absolute increases in cannabis use disorder prevalence (MCL: 0·037% [0·027-0·048], 5·7% attributable to MCL; RCL: 0·042% [0·023-0·060], 6·0% attributable to RCL). Overall, associations of MCL and RCL with cannabis use disorder were greater in patients with chronic pain than in patients without chronic pain.

INTERPRETATION

Increasing cannabis use disorder prevalence among patients with chronic pain following state legalisation is a public health concern, especially among older age groups. Given cannabis commercialisation and widespread public beliefs about its efficacy, clinical monitoring of cannabis use and discussion of the risk of cannabis use disorder among patients with chronic pain is warranted.

FUNDING

NIDA grant R01DA048860, New York State Psychiatric Institute, and the VA Centers of Excellence in Substance Addiction Treatment and Education.

Increasing Use of Cannabis for Medical Purposes Among U.S. Residents, 2013-2020

INTRODUCTION

Cannabis use for medical purposes is legalized across 39 states and the District of Columbia in the U.S. The objective of this study was to evaluate temporal trends and correlates of cannabis use for medical purposes in the U.S.

METHODS

Data from the 2013-2020 National Survey on Drug Use and Health were used. Since 2013, medical cannabis use has been assessed using a dichotomous question asking whether any medical cannabis use was recommended by a doctor among those who used cannabis in the past 12 months. A modified Poisson model was used to estimate the average annual percentage change in medical cannabis use from 2013 to 2020. The analyses were repeated for key sociodemographic and clinical subgroups. Data were analyzed from September to November 2022.

RESULTS

The prevalence of U.S. residents using cannabis for medical purposes increased significantly from 1.2% in 2013-2014 to 2.5% in 2019-2020, with an average annual percentage change of 12.9% (95% CI=10.4, 15.5), and many of sociodemographic and clinical subgroups showed similar significant increases in cannabis use for medical purposes. In the multivariable-adjusted model, living in a state that legalized medical cannabis remained significantly associated with medical cannabis use (AOR=4.10; 95% CI=3.68, 4.56).

CONCLUSIONS

The study documents a continued nationwide increase in the use of cannabis for diverse medical purposes between 2013 and 2020, two decades after the first state passed legalizing legislation.

Medicinal Cannabis Use for Rheumatic Conditions in the US Versus Canada: Rationale for Use and Patient-Health Care Provider Interactions

OBJECTIVE

Understanding how medical cannabis (MC) use is integrated into medical practice for rheumatic disease management is essential. We characterized rationale for MC use, patient-physician interactions around MC, and MC use patterns among people with rheumatic conditions in the US and Canada.

METHODS

We surveyed 3406 participants with rheumatic conditions in the US and Canada, with 1727 completing the survey (50.7% response rate). We assessed disclosure of MC use to health care providers, MC authorization by health care providers, and MC use patterns and investigated factors associated with MC disclosure to health care providers in the US versus Canada.

RESULTS

Overall, 54.9% of US respondents and 78.0% of Canadians reported past or current MC use, typically because of inadequate symptom relief from other medications. Compared to those in Canada, fewer US participants obtained MC licenses, disclosed MC use to their health care providers, or asked advice on how to use MC (all P values <0.001). Overall, 47.4% of Canadian versus 28.2% of US participants rated their medical professionals as their most trusted information source. MC legality in state of residence was associated with 2.49 greater odds of disclosing MC use to health care providers (95% confidence interval: 1.49-4.16, P < 0.001) in the US, whereas there were no factors associated with MC disclosure in Canada. Our study is limited by our convenience sampling strategy and cross-sectional design.

CONCLUSION

Despite widespread availability, MC is poorly integrated into rheumatic disease care, with most patients self-directing use with minimal or no clinical oversight. Concerted efforts to integrate MC into education and clinical policy is critical.

Effects of U.S. State Medical Cannabis Laws on Treatment of Chronic Noncancer Pain

BACKGROUND

State medical cannabis laws may lead patients with chronic noncancer pain to substitute cannabis in place of prescription opioid or clinical guideline-concordant nonopioid prescription pain medications or procedures.

OBJECTIVE

To assess effects of state medical cannabis laws on receipt of prescription opioids, nonopioid prescription pain medications, and procedures for chronic noncancer pain.

DESIGN

Using data from 12 states that implemented medical cannabis laws and 17 comparison states, augmented synthetic control analyses estimated laws' effects on receipt of chronic noncancer pain treatment, relative to predicted treatment receipt in the absence of the law.

SETTING

United States, 2010 to 2022.

PARTICIPANTS

583 820 commercially insured adults with chronic noncancer pain.

MEASUREMENTS

Proportion of patients receiving any opioid prescription, nonopioid prescription pain medication, or procedure for chronic noncancer pain; volume of each treatment type; and mean days' supply and mean morphine milligram equivalents per day of prescribed opioids, per patient in a given month.

RESULTS

In a given month during the first 3 years of law implementation, medical cannabis laws led to an average difference of 0.05 percentage points (95% CI, -0.12 to 0.21 percentage points), 0.05 percentage points (CI, -0.13 to 0.23 percentage points), and -0.17 percentage points (CI, -0.42 to 0.08 percentage points) in the proportion of patients receiving any opioid prescription, any nonopioid prescription pain medication, or any chronic pain procedure, respectively, relative to what we predict would have happened in that month had the law not been implemented.

LIMITATIONS

This study used a strong nonexperimental design but relies on untestable assumptions involving parallel counterfactual trends. Statistical power is limited by the finite number of states. Results may not generalize to noncommercially insured populations.

CONCLUSION

This study did not identify important effects of medical cannabis laws on receipt of opioid or nonopioid pain treatment among patients with chronic noncancer pain.

PRIMARY FUNDING SOURCE

National Institute on Drug Abuse.

Cannabis use prevalence, patterns, and reasons for use among patients with cancer and survivors in a state without legal cannabis access

PURPOSE

Cannabis use among patients with cancer is common, yet data are limited regarding use patterns, reasons for use, and degree of benefit, which represents an unmet need in cancer care delivery. This need is salient in states without legal cannabis programs, where perceptions and behavior among providers and patients may be affected.

METHODS

A cross-sectional survey of patients with cancer and survivors at the Hollings Cancer Center at the Medical University of South Carolina (no legal cannabis marketplace in SC) was completed as part of the NCI Cannabis Supplement. Patients (ages 18 +) were recruited using probability sampling from patient lists (N = 7749 sampled; N = 1036 completers). Weight-adjusted Chi-square tests compared demographics and cancer details among patients using cannabis since diagnosis versus those not using cannabis, while weighted descriptives are presented for cannabis use prevalence, consumption, symptom management, and legalization beliefs.

RESULTS

Weighted prevalence of cannabis use since diagnosis was 26%, while current cannabis use was 15%. The most common reasons for cannabis use after diagnosis were difficulty sleeping (50%), pain (46%), and mood changes and stress, anxiety, or depression (45%). Symptom improvement was endorsed for pain (57%), stress/anxiety/depression (64%), difficulty sleeping (64%), and loss of appetite (40%).

CONCLUSIONS

Among patients with cancer and survivors at a NCI-designated cancer center within SC, a state without legal access to medical cannabis, prevalence rates, and reasons for cannabis use are consistent with emerging literature in oncology populations. These findings have implications for care delivery, and work is needed to inform recommendations for providers and patients.

Let's Match: Making Cannabis Policy Guided by Research

PURPOSE

The growth and increasing sophistication of the legal cannabis industry necessitates further scientific inquiry to establish an evidence-based policy path forward. However, policymakers must balance public demand for cannabis reform with the lack of scientific consensus on key issues. This Commentary discusses Massachusetts' statutory provisions supporting cannabis research, advances in social equity driven by data, and critical policy issues, which invite questions without clear scientific answers.

FINDINGS

Although the full breadth of inquiry needed cannot possibly be contained in a single article, this Commentary poses questions in 2 pertinent issue areas that affect adult and medical use. First, we discuss the current limitations on determining the scope and severity of cannabis-impaired driving and detecting impairment at any one point in time. Although experimental studies have found varying levels of impairment on driving ability, observational data have been inconclusive regarding the extent of traffic incidents involving cannabis impairment. A precise threshold for impairment and manner of detection must be established to develop just enforcement measures. Second, we discuss the lack of clinical standardization in medical cannabis use. In the absence of a consistent clinical framework, medical cannabis patients face undue burdens that limit access to treatment. A more well-defined clinical structure is needed to enhance use of and access to therapeutic cannabis treatment models.

IMPLICATIONS

Cannabis policy reform has gone forward at the will of voters despite the status of cannabis as a Schedule I controlled substance at the federal level, which has limited opportunities to research cannabis because it is commercially available. The implication of such limitations is realized by states leading cannabis reform, where unanswered questions present an opportunity for the scientific community to inform an evidence-based path forward in cannabis policy.

Assessment of Medical Cannabis and Health-Related Quality of Life

Importance

The use of cannabis as a medicine is becoming increasingly prevalent. Given the diverse range of conditions being treated with medical cannabis, as well as the vast array of products and dose forms available, clinical evidence incorporating patient-reported outcomes may help determine safety and efficacy.

Objective

To assess whether patients using medical cannabis report improvements in health-related quality of life over time.

Design, Setting, and Participants

This retrospective case series study was conducted at a network of specialist medical clinics (Emerald Clinics) located across Australia. Participants were patients who received treatment for any indication at any point between December 2018 and May 2022. Patients were followed up every mean (SD) 44.6 (30.1) days. Data for up to 15 follow-ups were reported. Statistical analysis was conducted from August to September 2022.

Exposure

Medical cannabis. Product types and cannabinoid content varied over time in accordance with the treating physician's clinical judgement.

Main Outcomes and Measures

The main outcome measure was health-related quality of life as assessed using the 36-Item Short Form Health Survey (SF-36) questionnaire.

Results

In this case series of 3148 patients, 1688 (53.6%) were female; 820 (30.2%) were employed; and the mean (SD) age was 55.9 (18.7) years at baseline before treatment. Chronic noncancer pain was the most common indication for treatment (68.6% [2160 of 3148]), followed by cancer pain (6.0% [190 of 3148]), insomnia (4.8% [152 of 3148]), and anxiety (4.2% [132 of 3148]). After commencing treatment with medical cannabis, patients reported significant improvements relative to baseline on all 8 domains of the SF-36, and these improvements were mostly sustained over time. After controlling for potential confounders in a regression model, treatment with medical cannabis was associated with an improvement of 6.60 (95% CI, 4.57-8.63) points to 18.31 (95% CI, 15.86-20.77) points in SF-36 scores, depending on the domain (all P < .001). Effect sizes (Cohen d) ranged from 0.21 to 0.72. A total of 2919 adverse events were reported, including 2 that were considered serious.

Conclusions and Relevance

In this case series study, patients using medical cannabis reported improvements in health-related quality of life, which were mostly sustained over time. Adverse events were rarely serious but common, highlighting the need for caution with prescribing medical cannabis.

Development of cannabis use disorder in medical cannabis users: A 9-month follow-up of a randomized clinical trial testing effects of medical cannabis card ownership

Background

Evidence for long-term effectiveness of commercial cannabis products used to treat medical symptoms is inconsistent, despite increasingly widespread use.

Objective

To prospectively evaluate the effects of using cannabis on self-reported symptoms of pain, insomnia, anxiety, depression, and cannabis use disorder (CUD) after 12 months of use.

Methods

This observational cohort study describes outcomes over 9 months following a 12-week randomized, waitlist-controlled trial (RCT: NCT03224468) in which adults (N = 163) who wished to use cannabis to alleviate insomnia, pain, depression, or anxiety symptoms were randomly assigned to obtain a medical marijuana card immediately (immediate card acquisition group) or to delay obtaining a card for 12 weeks delay (delayed card acquisition group). During the 9-month post-randomization period, all participants could use cannabis as they wished and choose their cannabis products, doses, and frequency of use. Insomnia, pain, depression, anxiety, and CUD symptoms were assessed over the 9-month post-randomization period.

Results

After 12 months of using cannabis for medical symptoms, 11.7% of all participants (n = 19), and 17.1% of those using cannabis daily or near-daily (n = 6) developed CUD. Frequency of cannabis use was positively correlated with pain severity and number of CUD symptoms, but not significantly associated with severity of self-reported insomnia, depression, or anxiety symptoms. Depression scores improved throughout the 9 months in all participants, regardless of cannabis use frequency.

Conclusions

Frequency of cannabis use was not associated with improved pain, anxiety, or depression symptoms but was associated with new-onset cannabis use disorder in a significant minority of participants. Daily or near-daily cannabis use appears to have little benefit for these symptoms after 12 months of use.

The effects of the 4/20 cannabis holiday and adult-use cannabis legalization on medical cannabis sales and medical cannabis patient registration in Arizona

BACKGROUND

This study examined whether the 4/20 cannabis holiday was associated with increases in medical cannabis sales from licensed dispensaries in Arizona from 2018-2021, and whether adult-use cannabis legalization (the vote in November 2020 and retail sales in January 2021) was associated with declines in medical cannabis sales and in the number of registered medical patients.

METHODS

Data came from the Arizona Medical Marijuana Program monthly reports from January 2018-December 2021. The reports show daily sales from licensed medical cannabis dispensaries (i.e., the number of medical cannabis dispensary transactions and the amount of cannabis sold in pounds), which we averaged by week, and show the number of registered medical cannabis patients each month. Autoregressive integrated moving average models were used to test changes in these outcomes associated with the 4/20 cannabis holiday and with legalization of adult-use cannabis.

RESULTS

During the week of the 4/20 cannabis holiday, medical cannabis dispensary transactions abruptly increased by an average of 2,319.4 transactions each day (95% CI: 1636.1, 3002.7), and the amount of medical cannabis sold increased by an average of 120.3 pounds each day (95% CI: 99.3-141.3). During the first week of adult-use cannabis sales in late January 2021, medical cannabis dispensary transactions abruptly decreased by an average of 5,073 transactions each day (95% CI: -5,929.5, -4216.7), and the amount of medical cannabis sold decreased by an average of 119.1 pounds each day (95% CI: -144.2, -94.0). Moreover, medical cannabis sales continued to gradually decline each week after the start of adult-use retail sales, with declines in sales preceding declines in registered patients. By December 2021, slightly over a year after the vote to legalize adult-use cannabis, the actual number of registered medical cannabis patients fell short of the forecasted number, had adult-use not been legalized, by 36.5%. Moreover, the number of medical dispensary transactions and the amount of medical cannabis sold fell short of expectations, had adult-use cannabis not been legalized, by 58% and 53%, respectively.

CONCLUSIONS

Findings document the blurred boundary between medical and non-medical cannabis use and are consistent with the possibility that medical cannabis legalization contributes to increases in adult cannabis use and dependence.

Sperm capacitation and transcripts levels are altered by in vitro THC exposure

BACKGROUND

Delta-9-tetrahydrocannabinol (THC) is the primary phytocannabinoid responsible for the psychoactive properties of cannabis and is known to interact with the endocannabinoid system, which is functionally present in the male reproductive system. Since cannabis consumption is the highest among reproductive aged males, the current study aimed to further investigate the effects of THC exposure to phenotypical, physiological, and molecular parameters in sperm. Bull sperm of known fertility were used as a translational model for human sperm and subjected to in vitro treatment with physiologically relevant experimental doses of THC. Sperm parameters, capacitation, apoptosis, and transcript levels were evaluated following treatment.

RESULTS

Motility, morphology, and viability of bovine sperm was unaltered from THC exposure. However, 0.32µM of THC caused an increased proportion of capacitating sperm (p < 0.05) compared to control and vehicle group sperm. Transcriptome analysis revealed that 39 genes were found to be differentially expressed by 0.032µM THC exposure, 196 genes were differentially expressed by 0.32µM THC exposure, and 33 genes were differentially expressed by 3.2µM THC. Secondary analysis reveals pathways involving development, nucleosomes, ribosomes and translation, and cellular metabolism to be significantly enriched.

CONCLUSION

Phytocannabinoid exposure to sperm may adversely affect sperm function by stimulating premature capacitation. These findings also show for the first time that spermatozoal transcripts may be altered by THC exposure. These results add to previous research demonstrating the molecular effects of cannabinoids on sperm and warrant further research into the effects of cannabis on male fertility.

The evolving culture of medical cannabis in Canada for the management of chronic pain

Although used therapeutically for millennia, cannabis has been a prohibited substance worldwide for most of the 20th Century. With revision of prohibitive regulations in many jurisdictions during the past 2 decades, cannabis is increasingly available to patients as a potential treatment option for various symptoms. Pain relief, sleep promotion and alleviation of distress, depression and anxiety are the most common reasons for cannabis use. Canada has been at the forefront of medical cannabis (MC) legislation revisions to enable and facilitate access for therapeutic use. Although initially viewed with caution and stigma, attitudes to cannabis in general have changed. Medical cannabis is identified as the herbal plant product sourced from a grower/producer and is not at present a regulated pharmaceutical product. Medical cannabis use is currently prevalent in Canada but has bypassed the rigorous study required for usual drug approval. Although uptake has been enthusiastic by patients, the medical community has voiced cautions and concerns. Access to medical cannabis is fairly easy once an approval document is obtained from a healthcare professional, but without obligation for medical or pharmacy oversight. The greatest concern is a dearth of sound clinical evidence for effects and harms. Emerging concerns include prevalent patient self-management with information based on personal research, an abundance of on-line information which may not always be accurate, the emergence of designated "cannabis clinics," potential risks to society due to accidents, and high cost of the legal medical product leading to access via the recreational market. With cannabis now entrenched in Canadian healthcare, physicians must be sufficiently knowledgeable to provide guidance that is evidence-based and will ensure personal and societal harm reduction. Examination of the changing culture of medical cannabis in Canada will provide insight for countries that may be anticipating similar revisions of cannabis regulations to allow cannabis access for their patient population and learn from the issues created by recreational legalization.

The association between cannabis and codeine use: a nationally representative cross-sectional study in Canada

Background

Due to the growing use of cannabis for the purposes of pain relief, evidence is needed on the impact of cannabis use on concurrent analgesic use. Therefore, our objective was to evaluate the association between the use of cannabis and codeine.

Methods

We conducted a cross-sectional study using data from the nationally representative Canadian Tobacco, Alcohol and Drugs Survey (2017). The primary explanatory variable was self-reported use of cannabis within the past year. The outcome was the use of codeine-containing product(s) within the past year. We used multivariable binomial logistic regression models.

Results

Our study sample comprised 15,459 respondents including 3338 individuals who reported cannabis use within the past year of whom 955 (36.2%) used it for medical purposes. Among individuals who reported cannabis use, the majority were male (N = 1833, 62.2%). Self-reported use of cannabis was associated with codeine use (adjusted odds ratio [aOR] 1.89, 95% CI 1.36 to 2.62). Additionally, when limited to cannabis users only, we found people who used cannabis for medical purposes to be three times more likely to also report codeine use (adjusted odds ratio [aOR] 2.96, 95% CI 1.72 to 5.09).

Discussion

The use of cannabis was associated with increased odds of codeine use, especially among individuals who used it for medical purposes. Our findings suggest a potential role for healthcare providers to be aware of or monitor patients’ use of cannabis, as the long-term adverse events associated with concurrent cannabis and opioid use remain unknown.

Contemplating cannabis? The complex relationship between cannabinoids and hepatic metabolism resulting in the potential for drug-drug interactions

The majority of states have fully legalized the use of medical cannabis (MC), and nearly all other states allow limited access to cannabidiol (CBD), a non-intoxicating constituent of cannabis often touted for a range of therapeutic indications. Further, the Agricultural Improvement Act of 2018 legalized hemp-derived products in all 50 states; typically high in CBD, these products are derived from cannabis varieties containing ≤0.3% delta-9-tetrahydrocannabinol (THC) by weight. The recent "green rush" has resulted in a striking increase in cannabis use among patients and consumers who often use a wide variety of novel product types, each with a unique blend of cannabinoid constituents. Importantly, however, several cannabinoids have the potential to cause drug-drug interactions (DDI) with other medications, primarily due to their involvement with the hepatic cytochrome P450 (CYP450) system. This article examines the potential for individual cannabinoids, particularly CBD, to interact with the hepatic metabolic system, which is concerning given its involvement in the metabolism of commonly-prescribed medications. CBD and other cannabinoids are metabolized extensively by the CYP450 system, and also inhibit many of these enzymes, potentially leading to variable serum levels of other medications, as well as variable levels of cannabinoids when other medications modify the system. As access and interest in cannabinoid-based products continues to increase, critical questions remain unanswered regarding their safety. The complex relationship between cannabinoids and the hepatic metabolic system, including common potential DDI resulting from cannabinoid exposure, are explored along with the clinical significance of these potential interactions and monitoring or mitigation strategies.