Use of Cannabis and Other Pain Treatments Among Adults With Chronic Pain in US States With Medical Cannabis Programs

Prevalence and predictors of substance use as a factor in suicide in the USA, 2015-2020: a repeated cross-sectional analysis

Background

US rates of substance abuse and suicide mortality increased dramatically in recent years, but little is known about how rising rates of drug and alcohol use are associated with suicide. This study explores the role of substance use in suicide between 2015 and 2020 and identifies individual and geographical factors associated with these patterns.

Methods

Repeated cross-sectional data on 103 817 suicide decedents drawn from the 2015-2020 National Violent Death Reporting System, combined with Census geographical data, are examined. Available toxicology reports are investigated to identify shifts in substances involved in suicide. A mixed effects logistic model is applied to identify factors associated with the probability of substance use as a precipitating circumstance for suicide.

Results

Close to one in five suicide decedents had a substance-related circumstance. Relative to 2015, the probability of drug or alcohol problems surrounding suicide is higher in subsequent years (eg, in 2020, the probability is 2.6% and 2.5% higher, respectively). The detection of alcohol, the substance most identified in toxicology reports, remained stable over the period. Positive tests for prescription opioids and benzodiazepines declined while those for illicit opioids, marijuana and amphetamines increased. The probability of a drug abuse suicide circumstance is higher among white (Average Marginal Effect (AME) =0.038) and male (AME=0.006) decedents, and lower among those with a college degree (AME=-0.099) and who are foreign-born (AME=-0.078). For alcohol-related suicide circumstances, the corresponding AMEs are 0.033 (white), 0.055 (male), -0.045 (college degree) and -0.035 (foreign-born). After adjusting for individual characteristics, county median household income is associated with a reduced probability of drug abuse circumstances but a higher probability of alcohol problems. Unmet need for treatment at the state level is associated with a higher probability of alcohol-related suicide (AME=0.022).

Conclusions

Findings suggest shifts in the substances linked to suicide and reveal the importance of a place's social structure in shaping the substance use-suicide nexus.

The Combined Relationship of Prescription Drug Monitoring Program Enactment and Medical Cannabis Laws with Chronic Pain-Related Healthcare Visits

BACKGROUND

U.S. state electronic prescription drug monitoring programs (PDMPs) are associated with reduced opioid dispensing among people with chronic pain and may impact use of other chronic pain treatments. In states with medical cannabis laws (MCLs), patients can use cannabis for chronic pain management, reducing their need for chronic-pain related treatment visits and moderating effects of PDMP laws.

OBJECTIVE

Given high rates of chronic pain among Medicaid enrollees, we examined associations between PDMP enactment in the presence or absence of MCL on chronic pain-related outpatient and emergency department (ED) visits.

DESIGN

We created annual cohorts of Medicaid enrollees with chronic pain diagnoses using national Medicaid claims data from 2002-2013 and 2016. Negative binomial hurdle models produced adjusted odds ratios (aOR) for the likelihood of any chronic pain-related outpatient or ED visit and incident rate ratios (IRR) for the rate of visits among patients with ≥ 1 visit.

PARTICIPANTS

Medicaid enrollees aged 18-64 years with chronic pain (N = 4,878,462).

MAIN MEASURES

A 3-level state-year variable with the following categories: 1) no PDMP, 2) PDMP enactment in the absence of MCL, or 3) PDMP enactment in the presence of MCL. Healthcare codes for chronic pain-related outpatient and ED visits each year.

KEY RESULTS

The sample was primarily female (67.2%), non-Hispanic White (51.2%), and ages 40-55 years (37.2%). Compared to no-PDMP states, PDMP enactment in the absence of MCL was not associated with chronic pain-related outpatient visits but PDMP enactment in the presence of MCL was associated with lower odds of chronic pain-related outpatient visits (aOR = 0.81, 95% CI:0.71-0.92). PDMP enactment was not associated with ED visits, irrespective of MCL.

CONCLUSIONS

During a period of PDMP and MCL expansion, our findings suggest treatment shifts for persons with chronic pain away from outpatient settings, potentially related to increased use of cannabis for chronic pain management.

Older Adult Perspectives on Integrative Pain Management, Analgesics and Educational Preferences

Older adults' (adults over age 50) preferences for educational programs on integrative pain management have not been adequately explored. Integrative pain management uses a holistic approach combining traditional medical treatments with alternative non-pharmacological practices. Pain-related education targeting older adults is supported by prior research, but to our knowledge older adult perspectives and learning preferences have not been investigated. Our objective was to explore older adult views on integrative pain management, specifically their educational needs and preferences, for patient-centered pain management education. Patients >50 years of age with chronic pain (pain for three months or longer), were eligible for enrollment in virtual focus groups. Audio recordings were transcribed, coded, and analyzed via a mixed inductive-deductive framework approach using ATLAS.ti version 23.0.8.0 (Microsoft, Redmond, WA, USA). Descriptive statistics were performed using Stata 16 (StataCorp., College Station, TX, USA).  There were 16 participants and five themes generated: opioid/analgesic perceptions, integrative pain management, patient-provider relationship, and educational needs/preferences. All participants felt traditional interactions with healthcare providers did not adequately address their educational needs. There were discordant views on opioids, some noted positive impacts on pain and function and others feared addiction and side effects. Subthemes on the patient-provider relationship were identified including misalignment in treatment preferences/goals and communication gaps. Participants preferred virtual programs, incorporating demonstrations, audience interaction, and physical materials. These findings can be used to develop patient-centered educational programs.

Bidirectional relationships between pain and patterns of cannabis and tobacco use in a US nationally representative sample

ABSTRACT

One-fifth of US adults experience chronic pain, which is associated with increased tobacco and cannabis use. Although bidirectional relationships between tobacco and pain have been demonstrated, pathways between pain, cannabis use, and co-use of cannabis and tobacco are understudied. We aimed to estimate the effects of (1) substance use (exclusive and co-use of cannabis and tobacco) on later pain intensity, and (2) pain intensity on later substance use. Data were from 31,983 adults in biennial surveys (2015-2021) of the US nationally representative longitudinal Population Assessment of Tobacco and Health Study (n = 71,055 pairs of consecutive surveys; T1 and T2). Past-week pain intensity was dichotomized (≤4/10 no/low pain; >4/10 moderate/severe pain). Mutually exclusive substance use categories (past 30 days) were no cannabis/tobacco use; exclusive cannabis/tobacco use; and co-use. Logistic regression assessed whether T1 substance use affected moderate/severe pain at T2. Multinomial models assessed whether pain status at T1 affected substance use at T2. Compared with no cannabis/tobacco use at T1, co-use (OR: 2.29 [95% CI: 2.09-2.51]), exclusive tobacco use (2.00 [1.86-2.14]), and exclusive cannabis use (1.35 [1.13-1.61]) were all associated with moderate/severe pain at T2. Moderate/severe pain at T1 increased odds of co-use (2.43 [2.22-2.66]), exclusive tobacco (2.12 [1.98-2.28]), and exclusive cannabis use (1.46 [1.29-1.65]) compared with no cannabis/tobacco use at T2, and increased odds of co-use at T2 compared with exclusive cannabis/tobacco use. Findings demonstrated bidirectional relationships between pain and the exclusive use and co-use of cannabis and tobacco and indicate potential synergy in the co-use of cannabis and tobacco with respect to pain.

Pain Predicts Cannabis Initiation Among Emerging Adults: Results from the Population Assessment of Tobacco and Health (PATH) Study

Pain is highly prevalent among emerging adults (18-25 years old), and rates of cannabis use are increasing among this population. Research indicates pain is a unique risk factor and motivator for substance use. However, evidence for pain-cannabis use relations among emerging adults is largely cross-sectional, and the only prospective evidence focuses on the frequency, quantity, and consequences of cannabis use, not initiation. Accordingly, this is the first study to examine pain as a prospective predictor of cannabis initiation among emerging adults. Data were drawn from five annual waves of the Population Assessment of Tobacco and Health Study. Emerging adults who denied cannabis use at baseline (n = 4,185) were included in the analysis. At baseline, a tenth of emerging adults reported moderate/severe pain (≥4/10). Adjusted Cox regression analysis revealed that emerging adults with moderate/severe baseline pain were more likely to initiate cannabis use, and did so earlier over the subsequent 4 years, than those with no/low baseline pain. These findings provide initial evidence for pain as a risk factor for cannabis initiation during emerging adulthood. Future research is needed to identify mechanisms by which pain motivates cannabis initiation and to examine the utility of pain-targeted content in cannabis use prevention and intervention efforts among emerging adults.

Do Medical and Recreational Marijuana State Laws Impact Trends in Postoperative Opioid Prescriptions Among Patients Who Have Undergone TJA?

BACKGROUND

Total joint arthroplasty (TJA) is a painful procedure frequently managed with opioid medication, which puts patients at risk for chronic opioid use. Marijuana is a pain modifier and may be an effector of opioid-use reduction. Recently, many states have legalized the use of medical and recreational marijuana, and these legalization events have correlated with reductions in opioid prescriptions. This trend has not yet been demonstrated in the context of orthopaedic surgery, and there is limited evidence overall investigating the effect of marijuana on perioperative opioid use in TJA.

QUESTION/PURPOSES

(1) Is legalization of medical marijuana associated with changes in perioperative opioid use in patients who have undergone TJA? (2) Is legalization of recreational marijuana associated with changes in perioperative opioid use in patients who have undergone TJA? (3) Are these changes observed in any specific subpopulations of patients who have undergone TJA?

METHODS

The MarketScan Commercial and Medicare Supplemental Claims and Encounters Database was queried to assess the relative effect of marijuana legalization on perioperative opioid use in THA and TKA between May 1, 2017, and September 30, 2021, which was around and after the time that the opioid crisis was declared a public health emergency. We identified 129,132 inpatient TJA procedures (THA = 49,718, TKA = 79,414). The perioperative period was defined as 30 days before surgery and 90 days after surgery. We used the recreational and medical marijuana legalization effective dates in all 50 states and Washington, DC to conduct a difference-in-difference analysis to compare trends of outpatient opioid prescriptions among patients who underwent TJA in states with legalizations of medical or recreational marijuana with those among patients who underwent TJA in states without a change in marijuana legalization status.

RESULTS

We observed no impact of medical marijuana legalization on morphine milligram equivalent (MME)/day (difference-in-difference change 4.38 [95% confidence interval (CI) -4.49 to 13.22]). However, recreational marijuana legalization implementation was associated with an increase in MME/day (difference-in-difference change 8.83 [95% CI 0.22 to 17.43]). When we looked at specific patient groups, the implementations of medical and recreational marijuana laws were both associated with increases in perioperative opioid prescriptions in women, while recreational marijuana legalization was associated with increased opioid use in patients undergoing TKA and patients without prior use of opioids.

CONCLUSION

We did not identify differences with respect to medical marijuana legalization implementation. However, we found that recreational marijuana legalization was associated with an increase in perioperative MME/day for TJA. This is important because surgeons in states with the implementation of recreational marijuana law should be aware of the potential for increased marijuana availability for their patients and how this may impact their postoperative course, particularly with respect to pain and opioid utilization.

LEVEL OF EVIDENCE

Level III, therapeutic study.

A Scoping Review of Observational Research on Cannabis Use for Symptom Management in HIV and Cancer: Implications for Cannabis Nursing

BACKGROUND

People with HIV have a higher risk of developing non-AIDS-defining cancers in older age, leading to a significant population living with two conditions, HIV and cancer. There is an increasing interest in cannabis use for symptom management in people with chronic conditions; in 2023, the American Nurses Association officially recognised cannabis nursing as a specialty nursing practice focusing on the care of individuals seeking education/guidance in the therapeutic use of cannabis, supporting the urgency of its research. However, the scientific literature lacks a synthesised review in the focused populations.

AIM

To explore observational research on cannabis use for symptom management among people with HIV and/or cancer and identify gaps in current knowledge to inform future research and policy development.

METHODS

Following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses Extension for Scoping Reviews (PRISMA-ScR) checklist, a literature search of relevant articles was conducted in the databases PubMed (n = 552), PsycInfo (n = 204), CINAHL (n = 164) and Embase (n = 976). Upon screening 1738 articles, 142 were identified for full-text review and 51 were retained for data extraction.

RESULTS

There were more studies evaluating cannabis use among people with cancer than with HIV and no studies among people living with comorbid HIV and cancer. Most studies were cross-sectional with limited metrics on the perceived effectiveness and safety of cannabis use for symptom management and its dosing/mode of delivery for reducing symptoms. While studies focused on cannabis therapy under the provision of healthcare providers, individuals reported obtaining information about cannabis from friends/family/the Internet.

IMPLICATIONS FOR CANNABIS NURSING

This body of research could be strengthened by rigorous longitudinal study designs to build causal relationships on the therapeutic effects of cannabis use and the inclusion of reliable and valid symptom assessment measures over time, which facilitates developing clinical practice guidance and policymaking in cannabis nursing.

PATIENT OR PUBLIC CONTRIBUTION

No patient or public contribution.

Investigating the Relationship Between Cannabis Expectancies and Anxiety, Depression, and Pain Responses After Acute Flower and Edible Cannabis Use

Objective: Cannabis has been touted for a host of pharmacological and therapeutic effects and users commonly report reduced symptoms of physical and mental health conditions, including anxiety, depression, and chronic pain. While there is existing empirical evidence supporting these effects of cannabis use, little is known about the extent to which these effects result from pharmacological versus expectancy factors. We evaluated the associations between participants' cannabis expectancies and their acute self-reported reactions after using legal market forms of cannabis with varying levels of cannabidiol (CBD) and Δ9-tetrahydrocannabinol (THC) in three domains: anxiety, depression, and pain. Methods: Fifty-five flower and 101 edible cannabis users were randomly assigned and asked to purchase at a local dispensary one of three products containing varying levels of CBD and THC. Participants completed a baseline assessment where they reported expectancies about general health effects of cannabis use and an experimental mobile laboratory assessment where they administered their assigned products. Edible users also reported their domain-specific expectancies about cannabis use in improving anxiety, depression, and pain. Following administration, participants completed acute indicators of anxiety, depression, and pain operationalized through subjective acute tension, elation, and a single-item measure of pain. Results: Among flower users, more positive expectancies for cannabis to improve general health were correlated with greater reductions in tension at acute post-use. This finding was replicated among edible users. Unlike flower users, more positive expectancies for cannabis to improve general health were also correlated with greater increases in elation and greater reductions in pain among edible users. More positive expectancies for cannabis to improve depression and pain were also correlated with greater increases in elation and greater reductions in pain, respectively, among edible users. Conclusions: Cannabis users' expectancies significantly impacted some of the acute subjective effects of legal market cannabis products. Among both flower and edible users, consistent, significant expectancy effects were found. Results were consistent with prior findings and demonstrate the need to measure and control pre-existing expectancies in future research that involves cannabis administration. Clinical trial registration number: NCT03522103.

Select terpenes from Cannabis sativa are antinociceptive in mouse models of post-operative pain and fibromyalgia via adenosine A2a receptors

BACKGROUND

Terpenes from Cannabis show promise for pain management. Our lab found that the terpenes geraniol, linalool, β-caryophyllene, and α-humulene relieve chemotherapy-induced peripheral neuropathy via Adenosine A2a receptors (A2aR). This suggests terpenes as potential non-opioid, non-cannabinoid therapeutics. In this study, we investigated post-operative and fibromyalgia pain, expanding potential terpene applications to different pain types.

METHODS

Male and female CD-1 mice had their baseline mechanical sensitivity measured via von Frey filaments and underwent either paw incision surgery or reserpine-induced fibromyalgia (0.32 mg/kg, sc). After pain was established, the mice received 200 mg/kg ip of a terpene, and their mechanical sensitivity was measured over three hours. To determine the potential mechanism of action, mice were given the A2aR antagonist istradefylline (3.2 mg/kg, ip) 10 min before terpene, with mechanical sensitivity measured after. Hot plate pain testing was performed as a control.

RESULTS

Terpene treatment caused time-dependent elevation of the mechanical thresholds of the mice from both pain models, strongest for geraniol, then linalool or α-humulene, indicating that these four terpenes are anti-nociceptive in post-surgical and fibromyalgia pain. Pretreatment with istradefylline blocked antinociception, suggesting the terpenes act via the A2aR in these pain models. Terpenes had no effect on hot plate latencies, ruling out non-specific motor effects.

CONCLUSIONS

These results demonstrate that the terpenes geraniol, linalool, β-caryophyllene, and α-humulene may be a viable medication for post-operative and fibromyalgia pain relief. Their mechanism of action via the A2aR furthers our knowledge of its importance in pain processing and as a target of terpene drugs.

Impact of Early-Life Adversity on Cannabis Use: Exploring the Mediating and Moderating Effects of Chronic Pain

Background: Although research suggests that early-life adversity (ELA) and cannabis use are linked, researchers have not established factors that mediate or modify this relationship. Identifying such factors could help in developing targeted interventions. We explored chronic pain as a potential mediator or moderator of this relationship. Methods: Using an online study, we collected cross-sectional data about ELA, cannabis use, and chronic pain to test whether ELA (adverse childhood experiences total score) is associated with cannabis use, and to examine pain as a potential mediator or moderator. Cannabis use was examined two ways: times used per day, and categorized as non-, some, or regular use. Chronic pain was measured as present/absent and as the number of painful body locations (0-8). Analyses used linear and multinomial regression. Results: ELA, chronic pain, and cannabis use were common among respondents. ELA was strongly associated with both measures of cannabis use. The number of painful body locations modestly mediated the association of ELA with cannabis use, reducing the magnitude of regression coefficients by about 1/7. The number of painful body locations modified the association between ELA and cannabis use (p≤0.006), while chronic pain presence/absence (a less-informative measure) had only a nonsignificant modification effect (p≥0.10). When either ELA or pain was high, the other was not associated with cannabis use; when either ELA or pain was low, more painful locations or higher ELA (respectively) was associated with more intense cannabis use. Conclusion: These exploratory findings suggest the importance of ELA and chronic pain as factors contributing to cannabis use, and of accounting for these factors in developing treatment and prevention strategies addressing cannabis use.

The Intersection of Rurality, Unmet Treatment Need, and Cannabis Use for Adults with Chronic Pain

Objective

Rates of chronic pain are higher among rural versus urban individuals and rural individuals experience higher levels of socioeconomic disadvantage, poor or no health insurance coverage, and unmet treatment need. Medical cannabis is legal in Oklahoma. With 40% of Oklahoma's population living in rural areas, and nearly 17% uninsured, the medical legalization of cannabis may present as an accessible and relatively low-cost alternative treatment, particularly for those with chronic pain. This study investigated differences in cannabis use by rural (vs. urban) status and unmet (vs. met) treatment need among adults with and without chronic pain living in Oklahoma.

Method

To be eligible, participants had to be 18 years or older, reside in Oklahoma, and be able to read and write English-language surveys.

Results

The sample (N = 3622) was primarily made up of non-Hispanic White (70.4%) females (53.8%) in their early middle age (M = 41.80, SD = 16.88), employed full-time or part-time (53.8%), with some college/technical school (37.2%) or a bachelor's degree (28.5%). Nearly one-fifth of the sample (18.2%) endorsed chronic pain, and individuals with chronic pain were eight times more likely to report past 30-day cannabis use. No difference was detected when only rurality (vs. urban residence) was examined. Among adults with chronic pain, those who were rural dwelling and who reported unmet treatment need were almost two times more likely to report past 30-day cannabis use, compared to urban dwelling chronic pain adults with unmet treatment need.

Conclusions

In Oklahoma, adults in rural areas with unmet treatment need and chronic pain may benefit from increasing access to chronic pain treatment, as well as education on cannabis use and harm reduction strategies to inform healthcare decision-making.

Quantitative Analysis of Propofol Dosage in Cannabis Users: A Systematic Review and Meta-Analysis

Background: Rising cannabis use poses significant challenges in the administration of general anesthetics, particularly propofol, due to potential alterations in pharmacodynamics caused by tetrahydrocannabinol and its interactions with central nervous system receptors. This systematic review and meta-analysis aims to consolidate the existing literature to quantify propofol requirements in cannabis users, highlighting the complex relationship between cannabis use and anesthetic management. Methods: A systematic search of English-language literature was conducted to identify studies with data on propofol dosing in adult cannabis users. Propofol requirements were defined as the total intraoperative dose needed to achieve and maintain adequate sedation or anesthesia, assessed using parameters like monitoring and procedural tolerance. A random-effects model was used with DerSimonian-Laird estimations for pooled effect sizes and 95% confidence intervals. Heterogeneity was assessed using I2 and Cochran's Q statistics, and sensitivity analysis was conducted by grouping publications by design, size, and quality. Results: Eight qualified studies were identified with 2268 patients included. Patients who used cannabis were typically younger and more likely to smoke tobacco than non-users. Propofol requirements were significantly higher in cannabis users, who required an average additional dose of 47.33 mg compared to non-users. Subgroup analyses revealed that cannabis users undergoing general anesthesia needed an additional 30.57 mg intraoperatively, while those undergoing sedation for endoscopic procedures required an additional 53.02 mg. Conclusions: These results underscore the need for personalized anesthetic plans to accommodate physiological variations in cannabis users. However, the lack of standardized definitions for propofol requirements and the heterogeneity across studies necessitate caution in interpretation. The observed increase in propofol requirements suggests altered central nervous system sensitivities and receptor changes in cannabis users, emphasizing the need for further research to establish clear definitions, elucidate underlying mechanisms, and refine clinical guidelines for anesthetic management in this population.

The comparative effectiveness of medicinal cannabis for chronic pain versus prescription medication treatment

ABSTRACT

Reviews of the effectiveness of medicinal cannabis for chronic pain vary in their conclusions. IASP has identified that a key missing evidence in this debate is data from observational cohort studies, analyzed with comparative effectiveness methods. In a medically supervised context to the use of marijuana for chronic pain, we identified 440 patients certified for medical marijuana by pain specialists in a single healthcare system. They were characterized by a battery of patient-reported outcomes stored electronically in the University of Pittsburgh Patient Outcomes Repository for Treatment (PORT). At 3 months, 38.6% were responders, based on clinically meaningful improvements in pain, function, or global impression of change, and maintained this response at 6 months. In the 157 patients who were coprescribed opioids, at 6 months there was a mean 39.3% decrease in morphine milligram equivalents (P < 0.05 for the difference vs baseline). In addition, 8114 patients treated in the same pain clinics with prescription pain medications instead (nonopioid or opioid) during the same timeframe were selected from PORT as a control group for comparison. They had a 34.9% rate of response at 3 months. Using the causal inference method of stratified modeling, logistic regression revealed an odds ratio of 2.6 in favor of medical marijuana vs medication treatment (P < 0.01). Potential harms data were not available in the PORT registry. Medical marijuana was comparatively more effective than prescription medications for the treatment of chronic pain at 3 months, although the populations compared were slightly different.

The relationship between cannabis and cardiovascular disease: clearing the haze

Cannabis has been consumed for centuries, but global regulatory changes over the past three decades have increased the availability and consumption of cannabis. Cannabinoids are touted to have therapeutic potential for many diseases and could be a replacement for opioids for analgesia and sedation. However, cannabinoids can cause substantial adverse cardiovascular events that would mitigate any potential benefit. The endocannabinoid system regulates mood, satiety and memory, and modulates the cardiovascular system. The link between cannabinoids and cardiovascular disease, which used to be limited to evidence from preclinical studies, case reports and case series, is now evident in epidemiological studies. Cannabinoids adversely affect the cardiovascular system, causing myocardial infarction, cerebrovascular accidents, arrhythmia and heart failure. The effects of novel cannabinoids are unknown, and synthetic cannabinoids have the potential to cause even more substantial harm than traditional cannabinoids. Therefore, with the increasing availability and use of cannabis, the acute and chronic effects of this drug are becoming apparent.

Reducing medical cannabis use risk among Veterans: A descriptive study

BACKGROUND

Canadian Veterans experiencing chronic pain report concerns about accessing accurate information on the risks associated with medical cannabis (MC) use. The Lower Risk Cannabis Use Guidelines (LRCUG) were developed to equip individuals who use cannabis recreationally with safer-use strategies. Many of the harm reduction recommendations for recreational cannabis use are relevant and important considerations for MC use. The primary objective of our study was to assess Canadian Veterans' awareness of and interest in the LRCUG, and engagement in potential higher-risk MC use behaviours.

METHODS

Canadian Armed Forces Veterans living with chronic pain (N = 582) were recruited online and through the Chronic Pain Centre of Excellence for Canadian Veterans. Participants completed measures on: cannabis use (never, past, current use), sources of cannabis knowledge, mental health, and awareness of and interest in receiving the LRCUG. Chi-Square and post-hoc analyses characterized the sample and assessed for demographic differences based on cannabis use status and awareness of the LRCUG. Engagement in higher-risk MC use behaviours were aligned to LRCUG recommendations, and detailed descriptively.

RESULTS

Veterans who currently use cannabis were more likely to be unemployed (z = 3.62, p < .01), released as a Non-Commissioned Officer (z = -3.83, p < .01), and unable to work due a disability (z = -3.43, p < .01) than Veterans who do not currently use. Less than 30% of Veterans were aware of the LRCUG, with greater awareness among individuals who currently use cannabis (n = 356). Engagement in higher-risk MC use behaviours that contradicted LRCUG recommendations ranged from ~ 9% to ~ 85%. Approximately 9% of Veterans experienced co-morbid mental health concerns, yet their MC use was not for mental health purposes (LRCUG recommendation #7). Additionally, almost 85% of Veterans engaged in daily MC use (LRCUG recommendation #5). The majority of Veterans who currently use cannabis engaged in two or more higher-risk MC use behaviours (60.2%; LRCUG recommendation #12). Almost half of all Veterans received their cannabis information from a healthcare provider or the internet.

CONCLUSIONS

Our study suggests the importance of safer use guidelines tailored for MC use. Development of lower-risk MC use guidelines can support prescribing practitioners and Veterans with information needed for safer and better-informed MC use decisions, tailored to patients' needs and circumstances.

Considerations for Anesthesia in Older Adults with Cannabis Use

Over the past decade, legislative changes occurred in the USA and the western world that were followed by a substantial increase in reported use of cannabis among the general population. Among patients undergoing anesthesia for surgery or interventional procedures, older patients-often defined as adults over 65 years-are one of the fastest-growing populations. Within this group, the prevalence of cannabis use almost tripled over the past decade. In addition to habitual cannabis use, recommendations for treatment of chronic pain with cannabinoids have become increasingly more common. The clinical relevance of cannabis use in older adults is supported by recent studies linking it to increased anesthetic requirements as well as respiratory, cardiovascular, and psychiatric complications following surgery. Still, evidence remains equivocal, as these associations may largely depend on the type, frequency, and route of cannabis administration, and current research is mostly limited to retrospective cohort studies. Multisystemic effects of cannabis can become especially relevant in patients of advanced age undergoing anesthesia, characterized by physiological and pharmacodynamic alterations as well as a higher risks of drug-to-drug interactions. Best-practice guidelines emphasize the need for detailed, systematic preoperative screening for habits of cannabis use, including the history, type, and frequency, to guide perioperative management in these patients. This review discusses considerations for anesthesia in older patients with habitual cannabis use while highlighting strategies and recommendations to ensure safe and effective anesthesia care.

How Veterans with Chronic Pain Approach Using Cannabis for Symptom Management: Results from a Qualitative Interpretive Description Study

Introduction: Veterans use cannabis as a chronic pain treatment due to a combination of the easing of restrictions and dissatisfaction with care standards. The segregation of medical cannabis from conventional health systems may translate to opportunities and disadvantages that are not well defined. Our study aimed to characterize how Veterans with chronic pain approach using cannabis for symptom management, including product access, developing a treatment plan, and its integration into daily life. Materials and Methods: We used an interpretive description design and conducted semi-structured interviews with U.S. Veterans in Michigan who had chronic pain; were aged 21 years or older; and (a) used cannabis, (b) were planning to use cannabis, or (c) interested in learning about how cannabis could help with pain. We analyzed deidentified interview transcripts to develop themes that focused on how Veterans approached new and continued use of cannabis for chronic pain management. Results: Participants were Veterans with chronic pain, median age = 50 years (n = 32). Participants described how factors at the individual, relationship, community, and societal levels influenced their interest in and use of cannabis for chronic pain. We identified five main themes: (1) cannabis supports holistic wellness, but there are also undesired effects; (2) medical cannabis requires a personalized treatment approach; (3) Veterans seek expanded access to medical cannabis and more assurance regarding product safety and efficacy; (4) sociopolitical attitudes and advocacy shape medical cannabis acceptability; and (5) the interest in research to inform treatment approaches and facilitate access. Discussion: This article illustrates how Veterans approached using cannabis for chronic pain management. Findings illuminate the potential value of cannabis for Veterans with chronic pain while also highlighting numerous obstacles and limitations related to its use. There are opportunities for health care providers to support Veterans who are interested in cannabis while research regarding efficacy and safety continues. Future efforts should engage Veterans to collectively work toward a better understanding of cannabis as a pain treatment option.

"It frees your body from that pain thought": A mixed-methods exploration of patterns, contexts, and experiences of cannabis use for pain in rural communities

U.S. adults increasingly report using cannabis to manage chronic pain and rural areas have inadequate comprehensive pain management. Using mixed methods, we aimed to understand how and why some rural adults use cannabis for pain, including within the context of co-use with opioids. Participants (N = 14, Oklahoma) were rural-dwelling adults who used tobacco and ≥1 other substance, including cannabis and opioids, ≥3 days per week. Participants completed 14 days of ecological momentary assessment (EMA) regarding substance use and subsequent in-depth interviews discussing maps of their substance use reports. Half (7/14) described cannabis use for chronic pain, and most of these (85%) reported use on ≥75% of EMA days. The most frequently reported cannabis use motive was therapeutic/medicinal (90% of use reports). Most reports were of combusted cannabis (88% of use reports) at home (99% of use reports). Same-day use of cannabis and opioids was relatively common (45% of daily surveys), but seemingly not within close temporal proximity. Interview narratives characterized cannabis as modifying pain-adjacent factors (eg, thoughts), not eliminating pain itself. They recounted using a repertoire of substances to manage different pain dimensions (eg, intensity, quality) and balance perceived trade-offs of different substances. Participants described high medical cannabis access, low pain specialist access, and most physicians as unwilling to discuss cannabis for pain. The findings suggest that rural-dwelling patients could benefit from increased access to comprehensive pain management, having cannabis addressed within pain management provider discussions, and that risks and benefits of cannabis use for pain must be better established. PERSPECTIVE: This study used a geographically explicit EMA mixed method to gather rich, intensive pilot data on cannabis use and co-use for chronic pain in rural Oklahoma. It provides unique insights to inform future research on cannabis use among a vulnerable and understudied subgroup of adults with pain-rural residents.

Opioids and Cannabinoids in Neurology Practice

OBJECTIVE

Opioid and cannabinoid therapies for chronic pain conditions including neuropathic pain are controversial. Understanding patient and prescribing factors contributing to risks and implementing risk mitigation strategies optimizes outcomes.

LATEST DEVELOPMENTS

The ongoing transformation from a biomedical model of pain care toward a biopsychosocial model has been accompanied by a shift away from opioid therapy for pain, in particular for chronic pain. Opioid overdose deaths and opioid use disorder have greatly increased in the last several decades, initially because of increases in opioid prescribing and more recently associated with illicit drug use, in particular fentanyl derivatives. Opioid risk mitigation strategies may reduce risks related to opioid prescribing and tapering or discontinuation. Opioid therapy guidelines from the Centers for Disease Control and Prevention have become the consensus best practice for opioid therapy. Regulatory agencies and licensing medical boards have implemented restrictions and other mandates regarding opioid therapy. Meanwhile, interest in and use of cannabinoids for chronic pain has grown in the United States.

ESSENTIAL POINTS

Opioid therapy is generally not recommended for the chronic treatment of neuropathic pain conditions. Opioids may be considered for temporary use in patients with severe pain related to selected neuropathic pain conditions (such as postherpetic neuralgia), and only as part of a multimodal treatment regimen. Opioid risk mitigation strategies include careful patient selection and evaluation, patient education and informed consent, querying the state prescription drug monitoring programs, urine drug testing, and issuance of naloxone as potential rescue medication. Close follow-up when initiating or adjusting opioid therapy and frequent reevaluation during long-term opioid therapy is required. There is evidence for the efficacy of cannabinoids for neuropathic pain, with meaningful response rates in select patient populations.

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.

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.

Concurrent substance use among cancer patients with and without a history of cannabis use since cancer diagnosis at an NCI-Designated Cancer Center in Florida

BACKGROUND

Although substance use may have adverse impacts on cancer outcomes, little is known regarding patterns of concurrent substance use with cannabis among cancer patients. Our objective was to examine predictors of concurrent substance use with cannabis among cancer patients since their cancer diagnosis and explore perceptions of cannabis among these patients.

METHODS

Patients treated at a National Cancer Institute-designated comprehensive cancer center were invited to participate in an electronic survey regarding medical cannabis from August to November 2021. Survey data were linked to internal data resources including electronic health records and patient intake forms to obtain history of substance use (defined as within at least 3 months of cancer diagnosis) of cigarettes, injection drugs, high levels of alcohol, or clinically unsupervised prescription drugs (total n = 1094). Concurrent substance users were defined as those with any reported substance use and cannabis use at the time of cancer diagnosis. We used descriptive statistics (χ2 or exact tests) to compare groups and estimated adjusted odds ratios (AORs) with 95% confidence intervals (CIs) to identify predictors of substance use among users and nonusers of cannabis.

RESULTS

Approximately 45% (n = 489) of the sample reported cannabis use since their cancer diagnosis. Of patients who reported using cannabis, 20% self-reported concurrent polysubstance use, while 8% of cannabis nonusers reported substance use (P < .001). Among patients who use cannabis, those who reported 2 or more self-reported treatment-related symptoms (eg, pain, fatigue) were more likely to have self-reported concurrent substance use (AOR = 3.15, 95% CI = 1.07 to 9.27) compared with those without any symptoms. Among nonusers, those with lower educational background were more likely to have a history of concurrent substance use (AOR = 3.74, 95% CI = 1.57 to 8.92). Patients who use cannabis with concurrent substance use were more likely to report improved sleep (P = .04), increased appetite (P = .03), and treatment of additional medical conditions (P = .04) as perceived benefits of cannabis use.

CONCLUSIONS

High symptom burden may be associated with concurrent substance use with cannabis among cancer patients.

Pleiotropy and genetically inferred causality linking multisite chronic pain to substance use disorders

Individuals suffering from chronic pain develop substance use disorders (SUDs) more often than others. Understanding the shared genetic influences underlying the comorbidity between chronic pain and SUDs will lead to a greater understanding of their biology. Genome-wide association statistics were obtained from the UK Biobank for multisite chronic pain (MCP, Neffective = 387,649) and from the Million Veteran Program and the Psychiatric Genomics Consortium meta-analyses for alcohol use disorder (AUD, Neffective = 296,974), cannabis use disorder (CanUD, Neffective = 161,053), opioid use disorder (OUD, Neffective = 57,120), and problematic tobacco use (PTU, Neffective = 270,120). SNP-based heritability was estimated for each of the traits and genetic correlation (rg) analyses were performed to assess MCP-SUD pleiotropy. Bidirectional Mendelian Randomization analyses evaluated possible causal relationships. Finally, to identify and characterize individual loci, we performed a genome-wide pleiotropy analysis and a brain-wide analysis using imaging phenotypes available from the UK Biobank. MCP was positively genetically correlated with AUD (rg = 0.26, p = 7.55 × 10-18), CanUD (rg = 0.37, p = 8.21 × 10-37), OUD (rg = 0.20, p = 1.50 × 10-3), and PTU (rg = 0.29, p = 8.53 × 10-12). Although the MR analyses supported bi-directional relationships, MCP had larger effects on AUD (pain-exposure: beta = 0.18, p = 8.21 × 10-4; pain-outcome: beta = 0.07, p = 0.018), CanUD (pain-exposure: beta = 0.58, p = 2.70 × 10-6; pain-outcome: beta = 0.05, p = 0.014) and PTU (pain-exposure: beta = 0.43, p = 4.16 × 10-8; pain-outcome: beta = 0.09, p = 3.05 × 10-6) than the reverse. The genome-wide analysis identified two SNPs pleiotropic between MCP and all SUD investigated: IHO1 rs7652746 (ppleiotropy = 2.69 × 10-8), and CADM2 rs1248857 (ppleiotropy = 1.98 × 10-5). In the brain-wide analysis, rs7652746 was associated with multiple cerebellum and amygdala imaging phenotypes. When analyzing MCP pleiotropy with each SUD separately, we found 25, 22, and 4 pleiotropic variants for AUD, CanUD, and OUD, respectively. To our knowledge, this is the first large-scale study to provide evidence of potential causal relationships and shared genetic mechanisms underlying MCP-SUD comorbidity.

Adolescent-onset cannabis use and parenting young children: an investigation of differential effectiveness of a digital parenting intervention

Introduction

There is scant empirical work on associations between current and past cannabis use and parenting skills in parents of young children. As recreational cannabis use is now legal in nearly half of states in the U.S., cannabis use is becoming more ubiquitous.

Methods

In the current study, parents of toddler and pre-school age children were randomly assigned to participate in an app-based parenting skills program that included telehealth coaching (Family Check-Up Online; FCU-O), with a focus on parenting in the context of substance use. We aimed to test associations between adolescent-onset and current cannabis use and parent mental health and parenting skills, as well as whether effects of the FCU-O on parent mental health outcomes varied as a function of past cannabis use. Participants were 356 parents of children ages 1.5-5 participating in a randomized controlled trial of the FCU-O. Parents screened into the study if they reported current or past substance misuse or current depressive symptoms. After completing a baseline assessment, parents were randomly assigned to the FCU-O or control group and completed a follow-up assessment 3 months later. Parents retrospectively reported on the age when they initially used substances, as well as their current use.

Results

After accounting for current cannabis use, adolescent-onset cannabis use was significantly associated with higher symptoms of anxiety and depression, but not with parenting skills. Adolescent-onset cannabis use was found to significantly moderate the effect of the FCU-O on parents' anxiety symptoms. Specifically, the FCU-O was particularly effective in reducing anxiety symptoms for parents with adolescent-onset regular cannabis use, after accounting for current cannabis use.

Discussion

Adolescent-onset regular cannabis use may be a risk factor for later mental health challenges in parents of children under 5. An app-based parenting intervention may be particularly helpful in reducing symptoms of anxiety for parents who used cannabis regularly as adolescents. The findings have significant implications for the prevention of multigenerational risk for substance use and mental health challenges.

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.

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.

Drug Interactions of Tetrahydrocannabinol and Cannabidiol in Cannabinoid Drugs

BACKGROUND

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

METHODS

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

RESULTS

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

CONCLUSION

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

Impact of Δ9-Tetrahydrocannabinol and oxycodone co-administration on measures of antinociception, dependence, circadian activity, and reward in mice

Oxycodone is commonly prescribed for moderate to severe pain disorders. While efficacious, long-term use can result in tolerance, physical dependence, and the development of opioid use disorder. Cannabis and its derivatives such as Δ9-Tetrahydrocannabinol (Δ9-THC) have been reported to enhance oxycodone analgesia in animal models and in humans. However, it remains unclear if Δ9-THC may facilitate unwanted aspects of oxycodone intake, such as tolerance, dependence, and reward at analgesic doses. This study sought to evaluate the impact of co-administration of Δ9-THC and oxycodone across behavioral measures related to antinociception, dependence, circadian activity, and reward in both male and female mice. Oxycodone and Δ9-THC produced dose-dependent antinociceptive effects in the hotplate assay that were similar between sexes. Repeated treatment (twice daily for 5 days) resulted in antinociceptive tolerance. Combination treatment of oxycodone and Δ9-THC produced a greater antinociceptive effect than either administered alone, and delayed the development of antinociceptive tolerance. Repeated treatment with oxycodone produced physical dependence and alterations in circadian activity, neither of which were exacerbated by co-treatment with Δ9-THC. Combination treatment of oxycodone and Δ9-THC produced CPP when co-administered at doses that did not produce preference when administered alone. These data indicate that Δ9-THC may facilitate oxycodone-induced antinociception without augmenting certain unwanted features of opioid intake (e.g. dependence, circadian rhythm alterations). However, our findings also indicate that Δ9-THC may facilitate rewarding properties of oxycodone at therapeutically relevant doses which warrant consideration when evaluating this combination for its potential therapeutic utility.

Pain Management for Older Adults Across the Cognitive Trajectory

Purpose of review

This review investigated current research on the relationship between chronic pain and cognitive performance, subjective cognitive decline, and dementia. In addition, we reviewed current research on pain management in older adults across the cognitive trajectory.

Recent findings

Chronic pain remains a common problem in older adults. A new, international classification system highlights the complexity of chronic pain syndromes. Research supports relationships between chronic pain and changes in cognitive performance in generally healthy adults. Evidence also supports associations between pain and subjective cognitive decline, which is considered a possible precursor to dementia. The impact of dementia on pain expression is also reviewed. To manage pain in older adults, we present a multimodal pain management hierarchy that includes pharmacological and non-pharmacological treatments. To avoid the risks and side effects of analgesics, non-pharmacological treatment is recommended as the first line therapy for chronic pain. Medical cannabis and music therapy are two non-pharmacological treatments that have been the focus of substantial recent research; evidence supports their effectiveness in reducing pain and both strategies warrant further investigation.

Summary

Chronic pain is associated with different levels of cognitive decline across the cognitive trajectory. Medical cannabis and music therapy are the two emerging non-pharmacological treatment methods. Clinical studies with rigorous research design are needed to further investigate the effects of these two strategies on pain relief in older adults.

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.

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 Legalization and Cannabis Use Disorder in Veterans Health Administration Patients, 2005 to 2019

Background

The risk for cannabis use disorder (CUD) is elevated among U.S. adults with chronic pain, and CUD rates are disproportionately increasing in this group. Little is known about the role of medical cannabis laws (MCL) and recreational cannabis laws (RCL) in these increases. Among U.S. Veterans Health Administration (VHA) patients, we examined whether MCL and RCL effects on CUD prevalence differed between patients with and without chronic pain.

Methods

Patients with ≥1 primary care, emergency, or mental health visit to the VHA and no hospice/palliative care within a given calendar year, 2005-2019 (yearly n=3,234,382 to 4,579,994) were analyzed using VHA electronic health record (EHR) data. To estimate the role of MCL and RCL enactment in the increases in prevalence of diagnosed CUD and whether this differed between patients with and without chronic pain, staggered-adoption difference-in-difference analyses were used, fitting a linear binomial regression model with fixed effects for state, categorical year, time-varying cannabis law status, state-level sociodemographic covariates, a chronic pain indicator, and patient covariates (age group [18-34, 35-64; 65-75], sex, and race and ethnicity). Pain was categorized using an American Pain Society taxonomy of painful medical conditions.

Outcomes

In patients with chronic pain, enacting MCL led to a 0·14% (95% CI=0·12%-0·15%) absolute increase in CUD prevalence, with 8·4% of the total increase in CUD prevalence in MCL-enacting states attributable to MCL. Enacting RCL led to a 0·19% (95%CI: 0·16%, 0·22%) absolute increase in CUD prevalence, with 11·5% of the total increase in CUD prevalence in RCL-enacting states attributable to RCL. In patients without chronic pain, enacting MCL and RCL led to smaller absolute increases in CUD prevalence (MCL: 0·037% [95%CI: 0·03, 0·05]; RCL: 0·042% [95%CI: 0·02, 0·06]), with 5·7% and 6·0% of the increases in CUD prevalence attributable to MCL and RCL. Overall, MCL and RCL effects were significantly greater in patients with than without chronic pain. By age, MCL and RCL effects were negligible in patients age 18-34 with and without pain. In patients age 35-64 with and without pain, MCL and RCL effects were significant (p<0.001) but small. In patients age 65-75 with pain, absolute increases were 0·10% in MCL-only states and 0·22% in MCL/RCL states, with 9·3% of the increase in CUD prevalence in MCL-only states attributable to MCL, and 19.4% of the increase in RCL states attributable to RCL. In patients age 35-64 and 65-75, MCL and RCL effects were significantly greater in patients with pain.

Interpretation

In patients age 35-75, the role of MCL and RCL in the increasing prevalence of CUD was greater in patients with chronic pain than in those without chronic pain, with particularly pronounced effects in patients with chronic pain age 65-75. Although the VHA offers extensive behavioral and non-opioid pharmaceutical treatments for pain, cannabis may seem a more appealing option given media enthusiasm about cannabis, cannabis commercialization activities, and widespread public beliefs about cannabis efficacy. Cannabis does not have the risk/mortality profile of opioids, but CUD is a clinical condition with considerable impairment and comorbidity. Because cannabis legalization in the U.S. is likely to further increase, increasing CUD prevalence among patients with chronic pain following state legalization is a public health concern. The risk of chronic pain increases as individuals age, and the average age of VHA patients and the U.S. general population is increasing. Therefore, clinical monitoring of cannabis use and discussion of the risk of CUD among patients with chronic pain is warranted, especially among older patients.

Research in Context

Evidence before this study: Only three studies have examined the role of state medical cannabis laws (MCL) and/or recreational cannabis laws (RCL) in the increasing prevalence of cannabis use disorder (CUD) in U.S. adults, finding significant MCL and RCL effects but with modest effect sizes. Effects of MCL and RCL may vary across important subgroups of the population, including individuals with chronic pain. PubMed was searched by DH for publications on U.S. time trends in cannabis legalization, cannabis use disorders (CUD) and pain from database inception until March 15, 2023, without language restrictions. The following search terms were used: (medical cannabis laws) AND (pain) AND (cannabis use disorder); (recreational cannabis laws) AND (pain) AND (cannabis use disorder); (cannabis laws) AND (pain) AND (cannabis use disorder). Only one study was found that had CUD as an outcome, and this study used cross-sectional data from a single year, which cannot be used to determine trends over time. Therefore, evidence has been lacking on whether the role of state medical and recreational cannabis legalization in the increasing US adult prevalence of CUD differed by chronic pain status.Added value of this study: To our knowledge, this is the first study to examine whether the effects of state MCL and RCL on the nationally increasing U.S. rates of adult cannabis use disorder differ by whether individuals experience chronic pain or not. Using electronic medical record data from patients in the Veterans Health Administration (VHA) that included extensive information on medical conditions associated with chronic pain, the study showed that the effects of MCL and RCL on the prevalence of CUD were stronger among individuals with chronic pain age 35-64 and 65-75, an effect that was particularly pronounced in older patients ages 65-75.Implications of all the available evidence: MCL and RCL are likely to influence the prevalence of CUD through commercialization that increases availability and portrays cannabis use as 'normal' and safe, thereby decreasing perception of cannabis risk. In patients with pain, the overall U.S. decline in prescribed opioids may also have contributed to MCL and RCL effects, leading to substitution of cannabis use that expanded the pool of individuals vulnerable to CUD. The VHA offers extensive non-opioid pain programs. However, positive media reports on cannabis, positive online "information" that can sometimes be misleading, and increasing popular beliefs that cannabis is a useful prevention and treatment agent may make cannabis seem preferable to the evidence-based treatments that the VHA offers, and also as an easily accessible option among those not connected to a healthcare system, who may face more barriers than VHA patients in accessing non-opioid pain management. When developing cannabis legislation, unintended consequences should be considered, including increased risk of CUD in large vulnerable subgroups of the population.

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.

The relationship between cannabis use, schizophrenia, and bipolar disorder: a genetically informed study

BACKGROUND

The relationship between psychotic disorders and cannabis use is heavily debated. Shared underlying genetic risk is one potential explanation. We investigated the genetic association between psychotic disorders (schizophrenia and bipolar disorder) and cannabis phenotypes (lifetime cannabis use and cannabis use disorder).

METHODS

We used genome-wide association summary statistics from individuals with European ancestry from the Psychiatric Genomics Consortium, UK Biobank, and International Cannabis Consortium. We estimated heritability, polygenicity, and discoverability of each phenotype. We performed genome-wide and local genetic correlations. Shared loci were identified and mapped to genes, which were tested for functional enrichment. Shared genetic liabilities to psychotic disorders and cannabis phenotypes were explored using causal analyses and polygenic scores, using the Norwegian Thematically Organized Psychosis cohort.

FINDINGS

Psychotic disorders were more heritable than cannabis phenotypes and more polygenic than cannabis use disorder. We observed positive genome-wide genetic correlations between psychotic disorders and cannabis phenotypes (range 0·22-0·35) with a mixture of positive and negative local genetic correlations. Three to 27 shared loci were identified for the psychotic disorder and cannabis phenotype pairs. Enrichment of mapped genes implicated neuronal and olfactory cells as well as drug-gene targets for nicotine, alcohol, and duloxetine. Psychotic disorders showed a causal effect on cannabis phenotypes, and lifetime cannabis use had a causal effect on bipolar disorder. Of 2181 European participants from the Norwegian Thematically Organized Psychosis cohort applied in polygenic risk score analyses, 1060 (48·6%) were females and 1121 (51·4%) were males (mean age 33·1 years [SD 11·8]). 400 participants had bipolar disorder, 697 had schizophrenia, and 1044 were healthy controls. Within this sample, polygenic scores for cannabis phenotypes predicted psychotic disorders independently and improved prediction beyond the polygenic score for the psychotic disorders.

INTERPRETATION

A subgroup of individuals might have a high genetic risk of developing a psychotic disorder and using cannabis. This finding supports public health efforts to reduce cannabis use, particularly in individuals at high risk or patients with psychotic disorders. Identified shared loci and their functional implications could facilitate development of novel treatments.

FUNDING

US National Institutes of Health, the Research Council Norway, the South-East Regional Health Authority, Stiftelsen Kristian Gerhard Jebsen, EEA-RO-NO-2018-0535, European Union's Horizon 2020 Research and Innovation Programme, the Marie Skłodowska-Curie Actions, and University of Oslo Life Science.

Sleep disorders in chronic pain and its neurochemical mechanisms: a narrative review

Chronic pain (CP) is a prevalent problem, and more than half of patients with CP have sleep disorders. CP comorbidity with sleep disorders imposes immense suffering and seriously affects the patient's quality of life, which is a challenging issue encountered by clinicians. Although the reciprocal interactions between pain and sleep have been studied to some degree, there is still a lack of awareness and comprehensive description of CP comorbidity with sleep disorders. In this narrative review article, we summarize the current knowledge about the present estimates of the prevalence of comorbid sleep disorders in CP patients, sleep detection methods, sleep characterization in CP, and the effect of sleep disorders on CP and current therapies. We also summarize current knowledge of the neurochemical mechanisms of CP comorbidity with sleep disorders. In conclusion, insufficient attention has been paid to the role of sleep disorders in CP patients, and CP patients should be screened for sleep disorders in the clinic. Special attention should be given to a possible risk of drug-drug interaction when using two types of drugs targeting pain and sleep simultaneously. The current insight into the neurobiological mechanisms underlying CP comorbidity with sleep disorders is still rather limited.