Medical Marijuana Laws May Be Associated With A Decline In The Number Of Prescriptions For Medicaid Enrollees

Trends in Opioid Misuse among Marijuana Users and Non-Users in the U.S. from 2007-2017

Prescription-opioid misus e continues to be a significant health concern in the United States. The relationship between marijuana use and prescription-opioid misuse is not clear from the extant literature. This study examined national trends in prescription-opioid misuse among marijuana users and non-users using the 2007-2017 National Survey on Drug Use and Health. Cochran-Armitage tests were used to assess the statistical significance of changes in the yearly prevalence of prescription-opioid misuse and marijuana use. Multivariable logistic regression was used to examine the association between prescription-opioid and marijuana use adjusting for sociodemographic characteristics. From 2007 to 2017, marijuana use increased, while prescription-opioid misuse declined. Larger declines in prescription-opioid misuse were found among marijuana users than non-users. Marijuana ever-use was significantly associated with prescription-opioid misuse. Specifically, marijuana ever-users had higher odds of prescription-opioid misuse (ever-misuse [OR: 3.04; 95% CI, 2.68-3.43]; past-year misuse [OR: 3.44; 95% CI, 3.00-3.94]; and past-month misuse [OR: 4.50; 95% CI, 3.35-6.05]) compared to marijuana never-users. Similar results were found for the association of past-year and past-month marijuana use with prescription-opioid misuse. This study provides data on trends and associations about opioid misuse among marijuana users and non-users in a changing social environment of drug use in the United States. Future research should consider whether there is a causal relationship between marijuana use and prescription opioid misuse.

Frequency of cannabis and illicit opioid use among people who use drugs and report chronic pain: A longitudinal analysis

BACKGROUND

Ecological research suggests that increased access to cannabis may facilitate reductions in opioid use and harms, and medical cannabis patients describe the substitution of opioids with cannabis for pain management. However, there is a lack of research using individual-level data to explore this question. We aimed to investigate the longitudinal association between frequency of cannabis use and illicit opioid use among people who use drugs (PWUD) experiencing chronic pain.

METHODS AND FINDINGS

This study included data from people in 2 prospective cohorts of PWUD in Vancouver, Canada, who reported major or persistent pain from June 1, 2014, to December 1, 2017 (n = 1,152). We used descriptive statistics to examine reasons for cannabis use and a multivariable generalized linear mixed-effects model to estimate the relationship between daily (once or more per day) cannabis use and daily illicit opioid use. There were 424 (36.8%) women in the study, and the median age at baseline was 49.3 years (IQR 42.3-54.9). In total, 455 (40%) reported daily illicit opioid use, and 410 (36%) reported daily cannabis use during at least one 6-month follow-up period. The most commonly reported therapeutic reasons for cannabis use were pain (36%), sleep (35%), stress (31%), and nausea (30%). After adjusting for demographic characteristics, substance use, and health-related factors, daily cannabis use was associated with significantly lower odds of daily illicit opioid use (adjusted odds ratio 0.50, 95% CI 0.34-0.74, p < 0.001). Limitations of the study included self-reported measures of substance use and chronic pain, and a lack of data for cannabis preparations, dosages, and modes of administration.

CONCLUSIONS

We observed an independent negative association between frequent cannabis use and frequent illicit opioid use among PWUD with chronic pain. These findings provide longitudinal observational evidence that cannabis may serve as an adjunct to or substitute for illicit opioid use among PWUD with chronic pain.

Cannabinoid modulation of opioid analgesia and subjective drug effects in healthy humans

RATIONALE

Dozens of preclinical studies have reported cannabinoid agonist potentiation of the analgesic effects of μ-opioid agonists.

OBJECTIVES

The aim of this study was to determine if a cannabinoid agonist could potentiate opioid analgesia in humans using several laboratory pain models.

METHODS

Healthy participants (n = 10) with/out current drug use/pain conditions completed this within-subject, double-blind, placebo-controlled, randomized outpatient study. Nine 8-h sessions were completed during which dronabinol (0, 2.5, 5 mg, p.o.) was administered 1 h before oxycodone (0, 5, 10 mg, p.o.) for a total of 9 test conditions. Outcomes included sensory threshold and tolerance from four experimental pain models (cold pressor, pressure algometer, hot thermode, cold hyperalgesia), along with participant- and observer-rated, performance and physiological effects.

RESULTS

Oxycodone produced miosis (p < 0.05) and analgesic responses (e.g., pressure algometer [p < 0.05]), while dronabinol did not (p > 0.05). Depending on the dose combination, dronabinol attenuated or did not alter oxycodone analgesia; for example, dronabinol (2.5 mg) decreased the analgesic effects of oxycodone (10 mg) on pressure tolerance. Conversely, dronabinol increased oxycodone subjective effects (e.g., drug liking) (p < 0.05); oxycodone (5 mg) ratings of "high" were potentiated by 5 mg dronabinol (p < 0.05; placebo = 1.1 [± 0.7]; 5 mg oxycodone = 4.7 [± 2.2]; 5 mg dronabinol = 9.9 [± 8.4]; 5 mg oxycodone + 5 mg dronabinol = 37.4 [± 11.3]).

CONCLUSIONS

This study indicates that dronabinol did not enhance the analgesic effects of oxycodone and increased abuse- and impairment-related subjective effects. These data suggest that dronabinol may not be an effective or appropriate opioid adjuvant; it could potentially increase opioid dose requirements, while increasing psychoactive opioid effects.

Medical Marijuana Users are More Likely to Use Prescription Drugs Medically and Nonmedically

OBJECTIVES

Previous studies have found a negative population-level correlation between medical marijuana availability in US states, and trends in medical and nonmedical prescription drug use. These studies have been interpreted as evidence that use of medical marijuana reduces medical and nonmedical prescription drug use. This study evaluates whether medical marijuana use is a risk or protective factor for medical and nonmedical prescription drug use.

METHODS

Simulations based upon logistic regression analyses of data from the 2015 National Survey on Drug Use and Health were used to compute associations between medical marijuana use, and medical and nonmedical prescription drug use. Adjusted risk ratios (RRs) were computed with controls added for age, sex, race, health status, family income, and living in a state with legalized medical marijuana.

RESULTS

Medical marijuana users were significantly more likely (RR 1.62, 95% confidence interval [CI] 1.50-1.74) to report medical use of prescription drugs in the past 12 months. Individuals who used medical marijuana were also significantly more likely to report nonmedical use in the past 12 months of any prescription drug (RR 2.12, 95% CI 1.67-2.62), with elevated risks for pain relievers (RR 1.95, 95% CI 1.41-2.62), stimulants (RR 1.86, 95% CI 1.09-3.02), and tranquilizers (RR 2.18, 95% CI 1.45-3.16).

CONCLUSIONS

Our findings disconfirm the hypothesis that a population-level negative correlation between medical marijuana use and prescription drug harms occurs because medical marijuana users are less likely to use prescription drugs, either medically or nonmedically. Medical marijuana users should be a target population in efforts to combat nonmedical prescription drug use.

Is There Less Opioid Abuse in States Where Marijuana Has Been Decriminalized, Either for Medicinal or Recreational Use? A Clin-IQ

Opioid use, abuse, and associated mortality have reached an epidemic level. In some states, cannabis is being used to treat chronic pain. To examine the hypothesis that medical marijuana legislation may reduce adverse opioid-related outcomes if patients substitute cannabis for opioids for pain management, we conducted a clinical inquiry (Clin-IQ). We searched Ovid MEDLINE, Ovid MEDLINE In-Process, and Embase for studies using the search terms marijuana, cannabis, legal, marijuana smoking, medical marijuana, opioid-related disorders, cannabis use, medical cannabis, legal aspect, and opiate addiction. We included population-based articles published from January 1, 2012, through December 5, 2018, that assessed the relationship between marijuana use and decriminalization and the aforementioned opioid-related outcomes. Ten peer-reviewed studies met the inclusion criteria; 3 cross-sectional studies, 6 ecologic studies (ie, using aggregate data), and 1 retrospective cohort study. Eight studies reported associations between policies decriminalizing marijuana and reduced prescription opioid use, 1 study was inconclusive, and the retrospective cohort study reported an increase in adverse opioid-related outcomes. These results should be interpreted with caution given limitations associated with the studies' design. Results demonstrating association between marijuana decriminalization and opioid-related outcomes are mixed. Longitudinal studies are needed, and further analysis of this policy should continue to be tracked.

The Impact of Medical Marijuana Laws and Dispensaries on Self-Reported Health

Growing evidence suggests that medical marijuana laws have harm reduction effects across a variety of outcomes related to risky health behaviors. This study investigates the impact of medical marijuana laws on self-reported health using data from the Behavioral Risk Factor Surveillance System from 1993 to 2013. In our analyses we separately identify the effect of a medical marijuana law and the impact of subsequent active and legally protected dispensaries. Our main results show surprisingly limited improvements in self-reported health after the legalization of medical marijuana and legally protected dispensaries. Subsample analyses reveal strong improvements in health among non-white individuals, those reporting chronic pain, and those with a high school degree, driven predominately by whether or not the state had active and legally protected dispensaries. We also complement the analysis by evaluating the impact on risky health behaviors and find that the aforementioned demographic groups experience large reductions in alcohol consumption after the implementation of a medical marijuana law.

The effect of cannabis laws on opioid use

BACKGROUND

Many Americans rely on opioids at varying dosages to help ameliorate their suffering. However, empirical evidence is mounting that opioids are ineffective at controlling non-cancer related chronic pain, and many argue the strategies meant to relieve patient suffering are contributing to the growing opioid epidemic. Concurrently, several states now allow the use of medical cannabis to treat a variety of medical conditions, including chronic pain. Needing more exploration is the impact of cannabis laws on general opioid reliance and whether chronic pain sufferers are opting to use cannabis medicinally instead of opioids.

METHODS

This study investigates the effect of Medical Marijuana Laws (MML)s on opioid use and misuse controlling for a number of relevant factors using data from several years of the National Survey on Drug Use and Health and multivariate logistic regression and longitudinal analysis strategies.

RESULTS

Results provide evidence that MMLs may be effective at reducing opioid reliance as survey respondents living in states with medical cannabis legislation are much less apt to report using opioid analgesics than people living in states without such laws, net other factors. Results further indicate that the presence of medicinal cannabis legislation appears to have no influence over opioid misuse.

CONCLUSION

MMLs may ultimately serve to attenuate the consequences of opioid overreliance.

High-Frequency Medical Cannabis Use Is Associated With Worse Pain Among Individuals With Chronic Pain

Cannabis is widely used for chronic pain. However, there is some evidence of an inverse dose-response relationship between cannabis effects and pain relief that may negatively affect analgesic outcomes. In this cross-sectional survey, we examined whether daily cannabis use frequency was associated with pain severity and interference, quality of life measures relevant to pain (eg, anxiety and depressive symptoms), and cannabis use preferences (administration routes and cannabinoid ratio). Our analysis included 989 adults who used cannabis every day for chronic pain. Participant use was designated as light, moderate, and heavy (1-2, 3-4, and 5 or more cannabis uses per day, respectively). The sample was also subgrouped by self-reported medical-only use (designated MED, n = 531, 54%) versus medical use concomitant with a past-year history of recreational use (designated MEDREC, n = 458, 46%). In the whole sample, increased frequency of use was significantly associated with worse pain intensity and interference, and worse negative affect, although high-frequency users also reported improved positive affect. Subgroup analyses showed that these effects were driven by MED participants. Heavy MED participant consumption patterns showed greater preference for smoking, vaporizing, and high tetrahydrocannabinol products. In contrast, light MED participants had greater preference for tinctures and high cannabidiol products. Selection bias, our focus on chronic pain, and our cross-sectional design likely limit the generalizability of our results. Our findings suggest that lower daily cannabis use frequency is associated with better clinical profile as well as lower risk cannabis use behaviors among MED participants. Future longitudinal studies are needed to examine how high frequency of cannabis use interacts with potential therapeutic benefits. PERSPECTIVE: Our findings suggest that lower daily cannabis use frequency is associated with better clinical profile as well as safer use behaviors (eg, preference for cannabidiol and noninhalation administration routes). These trends highlight the need for developing cannabis use guidelines for clinicians to better protect patients using cannabis.

State marijuana laws and opioid overdose mortality

BACKGROUND

The opioid epidemic in the United States is a national public health crisis. In recent years, marijuana legalization has been increasingly adopted by state governments as a policy intervention to control the opioid epidemic under the premise that marijuana and opioids are substitutive substances. The purpose of this systematic review is to synthesize the empirical evidence regarding the impact of state marijuana laws on opioid overdose mortality and other opioid-related health outcomes.

METHOD

A comprehensive search of the research literature in 18 bibliographic databases returned 6640 records, with 5601 abstracts reviewed, 29 full text articles screened for eligibility, and 16 eligible studies included in the systematic review. Comprehensive Meta-Analysis software was used to generate summary estimates, forest plots, funnel plots, and heterogeneity statistics.

RESULTS

Of the 16 eligible studies, 4 assessed the association of state marijuana law status with opioid overdose mortality, 7 with prescription opioids dispensed, and the remaining with nonmedical use and opioid-related hospitalizations. Random effects modeling based on pooled data revealed that legalizing marijuana for medical use was associated with a statistically non-significant 8% reduction in opioid overdose mortality (95% confidence interval: - 0.21 to 0.04; p = 0.201) and a 7% reduction in prescription opioids dispensed (95% confidence interval: - 0.13 to - 0.01; p = 0.017). Legalizing marijuana for recreational use was associated with an additional 7% reduction in opioid overdose mortality in Colorado and 6% reduction in opioid prescriptions among fee-for-service Medicaid and managed care enrollees.

CONCLUSIONS

Legalizing marijuana might contribute to a modest reduction in opioid prescriptions. Evidence about the effect of marijuana legalization on opioid overdose mortality is inconsistent and inconclusive. If any, the effectiveness of state marijuana laws in reducing opioid overdose mortality appears to be rather small and limited to states with operational marijuana dispensaries. It remains unclear whether the presumed benefit of legalizing marijuana in reducing opioid-related harms outweighs the policy's externalities, such as its impact on mental health and traffic safety.

Medical marijuana laws are associated with increases in substance use treatment admissions by pregnant women

BACKGROUND AND AIMS

Between 2002 and 2014, past-month marijuana use among pregnant women in the United States increased 62%, nearly twice the growth of the general population. This growth coincides with the proliferation of state medical marijuana laws (MMLs) authorizing physicians to recommend marijuana for approved conditions. We estimated the association between MMLs and substance use treatment utilization among pregnant and non-pregnant women of reproductive age. We also examined whether the association varied across MML provisions, age groups and treatment referral sources to clarify potential pathways.

DESIGN

Nation-wide administrative data from the 2002-14 Treatment Episodes Data Set Admissions, and a difference-in-differences design that exploited the staggered implementation of MMLs to compare changes in outcomes before and after implementation between MML and non-MML states.

SETTING

Twenty-one MML and 27 non-MML US states.

PARTICIPANTS

Pregnant and non-pregnant women aged 12-49 admitted to publicly funded specialty substance use treatment facilities.

MEASUREMENTS

The primary outcome variable was the number of treatment admissions per 100 000 women aged 12-49, aggregated at the state-year level (n = 606). Admissions for marijuana, alcohol, cocaine and opioids were considered. The primary independent variable was an indicator of MML implementation in a state.

FINDINGS

Among pregnant women, the rate of marijuana treatment admissions increased by 4.69 [95% confidence interval (CI) = 1.32, 8.06] in MML states relative to non-MML states. This growth was accompanied by increases in treatment admissions involving alcohol (β = 3.19; 95% CI = 0.97, 5.410 and cocaine (β = 2.56; 95% CI = 0.34, 4.79), was specific to adults (β = 5.50; 95% CI = 1.52, 9.47) and was largest in states granting legal protection for marijuana dispensaries (β = 6.37; 95% CI = -0.97, 13.70). There was no statistically significant association between MMLs and treatment admissions by non-pregnant women.

CONCLUSIONS

Medical marijuana law implementation in US states has been associated with greater substance use treatment utilization by pregnant adult women, especially in states with legally protected dispensaries.

The Associations of Neighborhood Availability of Marijuana Dispensaries and DATA-2000 Waivered Providers with Hospital Stays Related to Opioids

Background: Evidence is emerging on how state-wide marijuana legalization and increased supply of DATA-2000 waivered providers may be associated with outcomes related to opioids. It is unknown whether such associations remain at the neighborhood level. Objectives: This study examined the associations of neighborhood availability of marijuana dispensaries and DATA-2000 waivered providers with opioid-related hospital stays. Methods: Discharge-level records of inpatient (N = 264,013) and observation stays (N = 12,621) were obtained from the Washington Comprehensive Hospital Abstract Reporting System from January through June 2016. Outcomes were indicators for inpatient stays related to opioid use disorder (OUD), inpatient stays related to opioid overdose, and observation stays related to OUD. Primary predictors were the density of marijuana dispensaries and DATA-2000 waivered providers at the zip code level. Multilevel logistic regressions with random intercepts were used to examine the cross-sectional associations, controlling for other patient and neighborhood characteristics. Results: Patients living in neighborhoods with one more recreational marijuana dispensaries per square mile were more likely (OR = 1.54, p = .017) to be diagnosed with OUD in inpatient stays. Living in neighborhoods with increased density of medical marijuana dispensaries or DATA-2000 waivered providers was not associated with being diagnosed with OUD or opioid overdose in inpatient or observation stays. Conclusions: Recreational and medical marijuana dispensaries were differentially associated with opioid-related hospital stays. Further investigations are warranted to explore the causal pathways of the findings.

Attitudes and Beliefs About Medical Usefulness and Legalization of Marijuana among Cancer Patients in a Legalized and a Nonlegalized State

Background: There is a growing preference for the use of marijuana for medical purposes, despite limited evidence regarding its benefits and potential safety risks. Legalization status may play a role in the attitudes and preferences toward medical marijuana (MM). Objectives: The attitudes and beliefs of cancer patients in a legalized (Arizona) versus nonlegalized state (Texas) regarding medical and recreational legalization and medical usefulness of marijuana were compared. Settings/Subjects: Two hundred adult cancer patients were enrolled from outpatient Palliative Care centers at Banner MD Anderson Cancer Center in Gilbert, AZ (n = 100) and The University of Texas MD Anderson Cancer Center in Houston, TX (n = 100). Design and Measurements: Adult cancer patients seen by the Palliative Care teams in the outpatient centers were evaluated. Various physical and psychosocial assessments were conducted, including a survey of attitudes and beliefs toward marijuana. Results: The majority of individuals support legalization of marijuana for medical use (Arizona 92% [85-97%] vs. Texas 90% [82-95%]; p = 0.81) and belief in its medical usefulness (Arizona 97% [92-99%] vs. Texas 93% [86-97%]; p = 0.33) in both states. Overall, 181 (91%) patients supported legalization for medical purposes whereas 80 (40%) supported it for recreational purposes (p < 0.0001). Patients preferred marijuana over current standard treatments for anxiety (60% [51-68%]; p = 0.003). Patients found to favor legalizing MM were younger (p = 0.027), had worse fatigue (p = 0.015), appetite (p = 0.004), anxiety (p = 0.017), and were Cut Down, Annoyed, Guilty, and Eye Opener-Adapted to Include Drugs (CAGE-AID) positive for alcohol/drugs (p < 0.0001). Conclusion: Cancer patients from both legalized and nonlegalized states supported legalization of marijuana for medical purposes and believed in its medical use. The support for legalization for medical use was significantly higher than for recreational use in both states.

Medical and non-medical cannabis use and risk of prescription opioid use disorder: Findings from propensity score matching

INTRODUCTION AND AIMS

Previous research suggested that cannabis use was associated with increased risks of prescription opioid misuse and use disorder. This study examined whether these associations differed by cannabis use purpose.

DESIGN AND METHODS

This is a secondary analysis of cross-sectional surveys with propensity score matching. Medical cannabis users (N = 1295), cannabis dual users with both medical and non-medical purposes (N = 707) and non-medical cannabis users (N = 18 666) were compared with cannabis non-users (N = 57 196) in the pooled 2013-2016 US nationally representative National Survey on Drug Use and Health. Propensity score models were applied to match cannabis non-users to cannabis users with different purposes with respect to potential confounders in individual socioeconomic characteristics, other substance use disorders and health conditions. In a matched sample, logistic regressions were used to assess associations.

RESULTS

Propensity score matching considerably improved the balance of the potential confounders between cannabis non-users and users. In a matched sample, non-medical cannabis use was associated with increased risks of prescription opioid misuse (OR = 3.15, 95%CI: 2.89-3.44) and use disorder (OR = 2.52, 95%CI: 2.06-3.10). Cannabis dual use and medical cannabis use were associated with increased risks of prescription opioid misuse (OR = 2.55, 95%CI: 1.78-3.65; OR = 2.15, 95%CI: 1.58-2.91, respectively), but they were not associated with prescription opioid use disorder.

DISCUSSION AND CONCLUSIONS

Medical and non-medical cannabis use both were both associated with increased risks of prescription opioid misuse. Medical cannabis use, however, was not associated with prescription opioid use disorder, and non-medical cannabis was. There appeared to be differential associations between cannabis use and prescription opioid use disorder by cannabis use purpose.

Association of US Medical Marijuana Laws With Nonmedical Prescription Opioid Use and Prescription Opioid Use Disorder

IMPORTANCE

Between 1997 and 2017, the United States saw increases in nonmedical prescription opioid use and its consequences, as well as changes in marijuana policies. Ecological-level research hypothesized that medical marijuana legalization may reduce prescription opioid use by allowing medical marijuana as an alternative.

OBJECTIVES

To investigate the association of state-level medical marijuana law enactment with individual-level nonmedical prescription opioid use and prescription opioid use disorder among prescription opioid users and to determine whether these outcomes varied by age and racial/ethnic groups.

DESIGN, SETTING, AND PARTICIPANTS

This cross-sectional study used restricted data on 627 000 individuals aged 12 years and older from the 2004 to 2014 National Survey on Drug Use and Health, a population-based survey representative of the civilian population of the United States. Analyses were completed from March 2018 to May 2018.

EXPOSURES

Time-varying indicator of state-level medical marijuana law enactment (0 = never law enactment, 1 = before law enactment, and 2 = after law enactment).

MAIN OUTCOMES AND MEASURES

Past-year nonmedical prescription opioid use and prescription opioid use disorder among prescription opioid users. Odds ratios of nonmedical prescription opioid use and prescription opioid use disorder comparing the period before and after law enactment were presented overall, by age and racial/ethnic group, and adjusted for individual- and state-level confounders.

RESULTS

The study sample included 627 000 participants (51.51% female; 9.88% aged 12-17 years, 13.30% aged 18-25 years, 14.30% aged 26-34 years, 25.02% aged 35-49 years, and 37.50% aged ≥50 years; the racial/ethnic distribution was 66.97% non-Hispanic white, 11.83% non-Hispanic black, 14.47% Hispanic, and 6.73% other). Screening and interview response rates were 82% to 91% and 71% to 77%, respectively. Overall, there were small changes in nonmedical prescription opioid use prevalence after medical marijuana law enactment (4.32% to 4.86%; adjusted odds ratio, 1.13; 95% CI, 1.06-1.20). Prescription opioid use disorder prevalence among prescription opioid users decreased slightly after law enactment, but the change was not statistically significant (15.41% to 14.76%; adjusted odds ratio, 0.95; 95% CI, 0.81-1.11). Outcomes were similar when stratified by age and race/ethnicity.

CONCLUSIONS AND RELEVANCE

This study found little evidence of an association between medical marijuana law enactment and nonmedical prescription opioid use or prescription opioid use disorder among prescription opioid users. Further research should disentangle the potential mechanisms through which medical marijuana laws may reduce opioid-related harm.

Association between medical cannabis laws and opioid overdose mortality has reversed over time

Medical cannabis has been touted as a solution to the US opioid overdose crisis since Bachhuber et al. [M. A. Bachhuber, B. Saloner, C. O. Cunningham, C. L. Barry, JAMA Intern. Med. 174, 1668–1673] found that from 1999 to 2010 states with medical cannabis laws experienced slower increases in opioid analgesic overdose mortality. That research received substantial attention in the scientific literature and popular press and served as a talking point for the cannabis industry and its advocates, despite caveats from the authors and others to exercise caution when using ecological correlations to draw causal, individual-level conclusions. In this study, we used the same methods to extend Bachhuber et al.’s analysis through 2017. Not only did findings from the original analysis not hold over the longer period, but the association between state medical cannabis laws and opioid overdose mortality reversed direction from −21% to +23% and remained positive after accounting for recreational cannabis laws. We also uncovered no evidence that either broader (recreational) or more restrictive (low-tetrahydrocannabinol) cannabis laws were associated with changes in opioid overdose mortality. We find it unlikely that medical cannabis—used by about 2.5% of the US population—has exerted large conflicting effects on opioid overdose mortality. A more plausible interpretation is that this association is spurious. Moreover, if such relationships do exist, they cannot be rigorously discerned with aggregate data. Research into therapeutic potential of cannabis should continue, but the claim that enacting medical cannabis laws will reduce opioid overdose death should be met with skepticism.

A cross-sectional examination of choice and behavior of veterans with access to free medicinal cannabis

Background: With a rise in public pressure to increase veteran access to medicinal cannabis, free cannabis collectives for military veterans are proliferating across the US. Objectives: The aim of the current study was to document which cannabis formulations and routes of administration are chosen by veterans with increased access to cannabis, and to determine whether cannabis is being used as a substitute for other licit and illicit drugs. Method: The current study collected cross-sectional self-report data on cannabis use, cannabinoid constituent composition, primary indication of use, and substitution practices among a sample of 93 US military veterans (84.9% male) with access to free cannabis. Result: Most of the sample reported using cannabinoids as a substitute for either alcohol, tobacco, prescription medications, or illicit substances, reported that they use cannabis frequently (Modal frequency >4x/day, Modal quantity = 5 to 8 grams/week), and primarily select higher-risk cannabis formulations (i.e., high THC/low CBD, smoked). The majority of the sample reported that they use cannabis to self-treat multiple physical and mental health conditions/symptoms. Conclusions: Results of the current study suggest that military Veterans with reduced barriers to access cannabis could be making both helpful and harmful choices regarding their cannabis use. These findings suggest that more guidance on the selection of cannabis-based products in this population is warranted, particularly as barriers to medicinal cannabis access are reduced.

Adverse Consequences of Co-Occurring Opioid Use Disorder and Cannabis Use Disorder Compared to Opioid Use Disorder Only

Background: While there is growing interest in the possibility that cannabis may be a partial substitute for opioids, studies have yet to examine whether individuals with co-occurring opioid and cannabis use disorders (OUD and CUD) have less risk of negative outcomes than those with OUD only. Objective: This study sought to compare the sociodemographic and clinical characteristics of patients diagnosed with co-occurring OUD and CUD to patients with OUD only, CUD only, and patients with any other drug use disorders. We hypothesized that co-occurring OUD and CUD would be associated with lower risk of inpatient admissions and emergency department (ED) visits, lower rates of homelessness, and fewer opioid prescriptions. Methods: Comparisons were based on bivariate analyses, logistic and linear multiple regression models of National Veterans Health Administration (VHA) data from Fiscal Year 2012. Results: Of the 234,181 (94% male) patients diagnosed with drug use disorders, 8.6% were diagnosed with co-occurring OUD and CUD; 33.3% with OUD only; 26.5% with CUD only; and 31.6% with other drug use disorders. Compared to the OUD only group (Mean = 4.8 (SD = 8.84)), the group with co-occurring OUD and CUD was associated with a lower number of opioid prescriptions (Mean = 3.79 (SD = 8.22)) (d = -0.16), but higher likelihood of inpatient psychiatric admission (RR = 1.95) and homelessness (RR = 1.52), and no significant difference in ED visits. Conclusions: These data highlight the need to further investigate whether the complex effects of cannabis use on patients with OUD are counterbalanced by potential benefits of reduced in opioid prescribing.

Good Samaritan harm reduction policy and drug overdose deaths

OBJECTIVE

To examine the effects of a harm reduction policy, specifically Good Samaritan (GS) policy, on overdose deaths.

DATA SOURCES/STUDY SETTING

Secondary data from multiple cause of death, mortality records paired with state harm reduction and substance use prevention policy.

STUDY DESIGN

We estimate fixed effects Poisson count models to model the effect of GS policy on overdose deaths for all, prescription, and illicit drugs, controlled substances, and opioids, while controlling for other harm reduction and substance use prevention policies.

DATA COLLECTION/EXTRACTION METHODS

We merge secondary data sources by state and year between 1999 and 2016.

PRINCIPAL FINDINGS

We fail to identify a statistically significant effect of GS policy in reducing overdose deaths broadly.

CONCLUSIONS

While we are unable to identify an effect of GS policy on overdose deaths, GS policy may have important effects on first-stage outcomes not investigated in this paper. Given recent state policy changes and rapid increase in many categories of overdose deaths, additional research should continue to examine the implementation and effects of harm reduction policy specifically and substance use prevention policy broadly.

Medical cannabis patterns of use and substitution for opioids & other pharmaceutical drugs, alcohol, tobacco, and illicit substances; results from a cross-sectional survey of authorized patients

BACKGROUND

A 239-question cross-sectional survey was sent out via email in January 2017 to gather comprehensive information on cannabis use from Canadian medical cannabis patients registered with a federally authorized licensed cannabis producer, resulting in 2032 complete surveys.

METHODS

The survey gathered detailed demographic data and comprehensive information on patient patterns of medical cannabis use, including questions assessing the self-reported impact of cannabis on the use of prescription drugs, illicit substances, alcohol, and tobacco.

RESULTS

Participants were 62.6% male (n = 1271) and 91% Caucasian (n = 1839). The mean age was 40 years old, and pain and mental health conditions accounted for 83.7% of all respondents (n = 1700). Then, 74.6% of respondents reported daily cannabis use (n = 1515) and mean amount used per day was 1.5 g. The most commonly cited substitution was for prescription drugs (69.1%, n = 953), followed by alcohol (44.5%, n = 515), tobacco (31.1%, n = 406), and illicit substances (26.6%, n = 136). Opioid medications accounted for 35.3% of all prescription drug substitution (n = 610), followed by antidepressants (21.5%, n = 371). Of the 610 mentions of specific opioid medications, patients report total cessation of use of 59.3% (n = 362).

CONCLUSIONS

This study offers a unique perspective by focusing on the use of a standardized, government-regulated source of medical cannabis by patients registered in Canada's federal medical cannabis program. The findings provide a granular view of patient patterns of medical cannabis use, and the subsequent self-reported impacts on the use of opioids, alcohol, and other substances, adding to a growing body of academic research suggesting that increased regulated access to medical and recreational cannabis can result in a reduction in the use of and subsequent harms associated with opioids, alcohol, tobacco, and other substances.

Pills to Pot: Observational Analyses of Cannabis Substitution Among Medical Cannabis Users With Chronic Pain

Chronic pain is common, costly, and challenging to treat. Many individuals with chronic pain have turned to cannabis as an alternative form of pain management. We report results from an ongoing, online survey of medical cannabis users with chronic pain nationwide about how cannabis affects pain management, health, and pain medication use. We also examined whether and how these parameters were affected by concomitant recreational use, and duration of use (novice: <1 year vs experienced: ≥1 year). There were 1,321 participants (59% female, 54% ≥50 years old) who completed the survey. Consistent with other observational studies, approximately 80% reported substituting cannabis for traditional pain medications (53% for opioids, 22% for benzodiazepines), citing fewer side effects and better symptom management as their rationale for doing so. Medical-only users were older (52 vs 47 years old; P < .0001), less likely to drink alcohol (66% vs 79%, P < .0001), and more likely to be currently taking opioids (21% vs 11%, P < .0001) than users with a combined recreational and medical history. Compared with novice users, experienced users were more likely to be male (64% vs 58%; P < .0001), take no concomitant pain medications (43% vs 30%), and report improved health (74% vs 67%; P = .004) with use. Given that chronic pain is the most common reason for obtaining a medical cannabis license, these results highlight clinically important differences among the changing population of medical cannabis users. More research is needed to better understand effective pain management regimens for medical cannabis users. Perspective: This article presents results that confirm previous clinical studies suggesting that cannabis may be an effective analgesic and potential opioid substitute. Participants reported improved pain, health, and fewer side effects as rationale for substituting. This article highlights how use duration and intentions for use affect reported treatment and substitution effects.

Recreational marijuana legalization and prescription opioids received by Medicaid enrollees

OBJECTIVES

Medical marijuana use may substitute prescription opioid use, whereas nonmedical marijuana use may be a risk factor of prescription opioid misuse. This study examined the associations between recreational marijuana legalization and prescription opioids received by Medicaid enrollees.

METHODS

State-level quarterly prescription drug utilization records for Medicaid enrollees during 2010-2017 were obtained from Medicaid State Drug Utilization Data. The primary outcome, opioid prescriptions received, was measured in three population-adjusted variables: number of opioid prescriptions, total doses of opioid prescriptions in morphine milligram equivalents, and related Medicaid spending, per quarter per 100 enrollees. Two difference-in-difference models were used to test the associations: eight states and DC that legalized recreational marijuana during the study period were first compared among themselves, then compared to six states with medical marijuana legalized before the study period. Schedule II and III opioids were analyzed separately.

RESULTS

In models comparing eight states and DC, legalization was not associated with Schedule II opioid outcomes; having recreational marijuana legalization effective in 2015 was associated with reductions in number of prescriptions, total doses, and spending of Schedule III opioids by 32% (95% CI: (-49%, -15%), p = 0.003), 30% ((-55%, -4.4%), p = 0.027), and 31% ((-59%, -3.6%), p = 0.031), respectively. In models comparing eight states and DC to six states with medical marijuana legalization, recreational marijuana legalization was not associated with any opioid outcome.

CONCLUSIONS

No evidence suggested that recreational marijuana legalization increased prescription opioids received by Medicaid enrollees. There was some evidence in some states for reduced Schedule III opioids following the legalization.

Self-Reported Marijuana Use Is Associated with Increased Use of Prescription Opioids Following Traumatic Musculoskeletal Injury

BACKGROUND

Cannabinoids are among the psychoactive substances considered as alternatives to opioids for the alleviation of acute pain. We examined whether self-reported marijuana use was associated with decreased use of prescription opioids following traumatic musculoskeletal injury.

METHODS

Our analysis included 500 patients with a musculoskeletal injury who completed a survey about their marijuana use and were categorized as (1) never a user, (2) a prior user (but not during recovery), or (3) a user during recovery. Patients who used marijuana during recovery indicated whether marijuana helped their pain or reduced opioid use. Prescription opioid use was measured as (1) persistent opioid use, (2) total prescribed opioids, and (3) duration of opioid use. Persistent use was defined as the receipt of at least 1 opioid prescription within 90 days of injury and at least 1 additional prescription between 90 and 180 days. Total prescribed opioids were calculated as the total morphine milligram equivalents (MME) prescribed after injury. Duration of use was the interval between the first and last opioid prescription dates.

RESULTS

We found that 39.8% of patients reported never having used marijuana, 46.4% reported prior use but not during recovery, and 13.8% reported using marijuana during recovery. The estimated rate of persistent opioid use ranged from 17.6% to 25.9% and was not associated with marijuana use during recovery. Marijuana use during recovery was associated with increases in both total prescribed opioids (regression coefficient = 343 MME; 95% confidence interval [CI] = 87 to 600 MME; p = 0.029) and duration of use (coefficient = 12.5 days; 95% CI = 3.4 to 21.5 days; p = 0.027) compared with no previous use (never users). Among patients who reported that marijuana decreased their opioid use, marijuana use during recovery was associated with increased total prescribed opioids (p = 0.008) and duration of opioid use (p = 0.013) compared with never users.

CONCLUSIONS

Our data indicate that self-reported marijuana use during injury recovery was associated with an increased amount and duration of opioid use. This is in contrast to many patients' perception that the use of marijuana reduces their pain and therefore the amount of opioids used.

LEVEL OF EVIDENCE

Therapeutic Level III. See Instructions for Authors for a complete description of levels of evidence.

Medical cannabis legalization and opioid prescriptions: evidence on US Medicaid enrollees during 1993-2014

BACKGROUND AND AIMS

While the United States has been experiencing an opioid epidemic, 29 states and Washington DC have legalized cannabis for medical use. This study examined whether state-wide medical cannabis legalization was associated with reduction in opioids received by Medicaid enrollees.

DESIGN

Secondary data analysis of state-level opioid prescription records from 1993-2014 Medicaid State Drug Utilization Data. Linear time-series regressions assessed the associations between medical cannabis legalization and opioid prescriptions, controlling for state-level time-varying policy covariates (such as prescription drug monitoring programs) and socio-economic covariates (such as income).

SETTING

United States.

PARTICIPANTS

Drug prescription records for patients enrolled in fee-for-service Medicaid programs that primarily provide health-care coverage to low-income and disabled people.

MEASUREMENTS

The primary outcomes were population-adjusted number, dosage and Medicaid spending on opioid prescriptions. Outcomes for Schedule II opioids (e.g. hydrocodone, oxycodone) and Schedule III opioids (e.g. codeine) were analyzed separately. The primary policy variable of interest was the implementation of state-wide medical cannabis legalization.

FINDINGS

For Schedule III opioid prescriptions, medical cannabis legalization was associated with a 29.6% (P = 0.03) reduction in number of prescriptions, 29.9% (P = 0.02) reduction in dosage and 28.8% (P = 0.04) reduction in related Medicaid spending. No evidence was found to support the associations between medical cannabis legalization and Schedule II opioid prescriptions. Permitting medical cannabis dispensaries was not associated with Schedule II or Schedule III opioid prescriptions after controlling for medical cannabis legalization. It was estimated that, if all the states had legalized medical cannabis by 2014, Medicaid annual spending on opioid prescriptions would be reduced by 17.8 million dollars.

CONCLUSION

State-wide medical cannabis legalization appears to have been associated with reductions in both prescriptions and dosages of Schedule III (but not Schedule II) opioids received by Medicaid enrollees in the United States.

Impact of co-administration of oxycodone and smoked cannabis on analgesia and abuse liability

Cannabinoids combined with opioids produce synergistic antinociceptive effects, decreasing the lowest effective antinociceptive opioid dose (i.e., opioid-sparing effects) in laboratory animals. Although pain patients report greater analgesia when cannabis is used with opioids, no placebo-controlled studies have assessed the direct effects of opioids combined with cannabis in humans or the impact of the combination on abuse liability. This double-blind, placebo-controlled, within-subject study determined if cannabis enhances the analgesic effects of low dose oxycodone using a validated experimental model of pain and its effects on abuse liability. Healthy cannabis smokers (N = 18) were administered oxycodone (0, 2.5, and 5.0 mg, PO) with smoked cannabis (0.0, 5.6% Δ⁹ tetrahydrocannabinol [THC]) and analgesia was assessed using the Cold-Pressor Test (CPT). Participants immersed their hand in cold water (4 °C); times to report pain (pain threshold) and withdraw the hand from the water (pain tolerance) were recorded. Abuse-related effects were measured and effects of oxycodone on cannabis self-administration were determined. Alone, 5.0 mg oxycodone increased pain threshold and tolerance (p ≤ 0.05). Although active cannabis and 2.5 mg oxycodone alone failed to elicit analgesia, combined they increased pain threshold and tolerance (p ≤ 0.05). Oxycodone did not increase subjective ratings associated with cannabis abuse, nor did it increase cannabis self-administration. However, the combination of 2.5 mg oxycodone and active cannabis produced small, yet significant, increases in oxycodone abuse liability (p ≤ 0.05). Cannabis enhances the analgesic effects of sub-threshold oxycodone, suggesting synergy, without increases in cannabis's abuse liability. These findings support future research into the therapeutic use of opioid-cannabinoid combinations for pain.

Cannabis for Chronic Pain: Challenges and Considerations

The National Academies of Sciences, Engineering, and Medicine has found substantial evidence that cannabis (plant) is effective for the treatment of chronic pain in adults, and moderate evidence that oromucosal cannabinoids (extracts, especially nabiximols) improve short-term sleep disturbances in chronic pain. The paradoxical superiority of the cannabis plant over cannabinoid molecules represents a challenge for the medical community and the established processes that define modern pharmacy. The expanding and variable legalization of cannabis in multiple states nationwide represents an additional challenge for patients and the medical community because recreational and medicinal cannabis are irresponsibly overlapped. Cannabis designed for recreational use (containing high levels of active ingredients) is increasingly available to patients with chronic pain who do not find relief with current pharmacologic entities, which exposes patients to potential harm. This article analyzes the available scientific evidence to address controversial questions that the current state of cannabis poses for health care professionals and chronic pain patients and sets the basis for a more open discussion about the role of cannabis in modern medicine for pain management. A critical discussion on these points, the legal status of cannabis, and considerations for health care providers is presented.

Association Between US State Medical Cannabis Laws and Opioid Prescribing in the Medicare Part D Population

Importance

Opioid-related mortality increased by 15.6% from 2014 to 2015 and increased almost 320% between 2000 and 2015. Recent research finds that the use of all pain medications (opioid and nonopioid collectively) decreases in Medicare Part D and Medicaid populations when states approve medical cannabis laws (MCLs). The association between MCLs and opioid prescriptions is not well understood.

Objective

To examine the association between prescribing patterns for opioids in Medicare Part D and the implementation of state MCLs.

Design, Setting, and Participants

Longitudinal analysis of the daily doses of opioids filled in Medicare Part D for all opioids as a group and for categories of opioids by state and state-level MCLs from 2010 through 2015. Separate models were estimated first for whether the state had implemented any MCL and second for whether a state had implemented either a dispensary-based or a home cultivation only-based MCL.

Main Outcomes and Measures

The primary outcome measure was the total number of daily opioid doses prescribed (in millions) in each US state for all opioids. The secondary analysis examined the association between MCLs separately by opioid class.

Results

From 2010 to 2015 there were 23.08 million daily doses of any opioid dispensed per year in the average state under Medicare Part D. Multiple regression analysis results found that patients filled fewer daily doses of any opioid in states with an MCL. The associations between MCLs and any opioid prescribing were statistically significant when we took the type of MCL into account: states with active dispensaries saw 3.742 million fewer daily doses filled (95% CI, -6.289 to -1.194); states with home cultivation only MCLs saw 1.792 million fewer filled daily doses (95% CI, -3.532 to -0.052). Results varied by type of opioid, with statistically significant estimated negative associations observed for hydrocodone and morphine. Hydrocodone use decreased by 2.320 million daily doses (or 17.4%) filled with dispensary-based MCLs (95% CI, -3.782 to -0.859; P = .002) and decreased by 1.256 million daily doses (or 9.4%) filled with home-cultivation-only-based MCLs (95% CI, -2.319 to -0.193; P = .02). Morphine use decreased by 0.361 million daily doses (or 20.7%) filled with dispensary-based MCLs (95% CI, -0.718 to -0.005; P = .047).

Conclusions and Relevance

Medical cannabis laws are associated with significant reductions in opioid prescribing in the Medicare Part D population. This finding was particularly strong in states that permit dispensaries, and for reductions in hydrocodone and morphine prescriptions.

Association of Medical and Adult-Use Marijuana Laws With Opioid Prescribing for Medicaid Enrollees

IMPORTANCE

Overprescribing of opioids is considered a major driving force behind the opioid epidemic in the United States. Marijuana is one of the potential nonopioid alternatives that can relieve pain at a relatively lower risk of addiction and virtually no risk of overdose. Marijuana liberalization, including medical and adult-use marijuana laws, has made marijuana available to more Americans.

OBJECTIVE

To examine the association of state implementation of medical and adult-use marijuana laws with opioid prescribing rates and spending among Medicaid enrollees.

DESIGN, SETTING, AND PARTICIPANTS

This cross-sectional study used a quasi-experimental difference-in-differences design comparing opioid prescribing trends between states that started to implement medical and adult-use marijuana laws between 2011 and 2016 and the remaining states. This population-based study across the United States included all Medicaid fee-for-service and managed care enrollees, a high-risk population for chronic pain, opioid use disorder, and opioid overdose.

EXPOSURES

State implementation of medical and adult-use marijuana laws from 2011 to 2016.

MAIN OUTCOMES AND MEASURES

Opioid prescribing rate, measured as the number of opioid prescriptions covered by Medicaid on a quarterly, per-1000-Medicaid-enrollee basis.

RESULTS

State implementation of medical marijuana laws was associated with a 5.88% lower rate of opioid prescribing (95% CI, -11.55% to approximately -0.21%). Moreover, the implementation of adult-use marijuana laws, which all occurred in states with existing medical marijuana laws, was associated with a 6.38% lower rate of opioid prescribing (95% CI, -12.20% to approximately -0.56%).

CONCLUSIONS AND RELEVANCE

The potential of marijuana liberalization to reduce the use and consequences of prescription opioids among Medicaid enrollees deserves consideration during the policy discussions about marijuana reform and the opioid epidemic.

Perceptions of the relative harmfulness of marijuana and alcohol among adults in Oregon

This study documents perceptions of the relative harmfulness of marijuana and alcohol to a person's health among adults in Oregon just before the first legal sales of marijuana for recreational use. We surveyed 1941 adults in Oregon in September 2015. Respondents were recruited using an address-based sampling (ABS) frame (n = 1314) and social media advertising (n = 627). Respondents completed paper surveys (ABS-mail, n = 388) or online surveys (ABS-online, n = 926; social media, n = 627). We used descriptive statistics and logistic regression models to examine perceptions of the relative harmfulness of marijuana and alcohol by sample characteristics, including substance use. About half of adults in Oregon (52.5%) considered alcohol to be more harmful to a person's health than marijuana. A substantial proportion considered the substances equally harmful (40.0%). Few considered marijuana to be more harmful than alcohol (7.5%). In general, respondents who were younger, male, and not Republican were more likely than others to consider alcohol more harmful than marijuana. Respondents who were older, female, and Republican were more likely to consider marijuana and alcohol equally harmful. Most individuals who reported using both marijuana and alcohol (67.7%) and approximately half of those who used neither substance (48.2%) considered alcohol to be more harmful than marijuana. Perceptions about the relative harmfulness of marijuana and alcohol may have implications for public health. As state lawmakers develop policies to regulate marijuana, it may be helpful to consider the ways in which those policies may also affect use of alcohol and co-use of alcohol and marijuana.

Epidemiology of Adult DSM-5 Major Depressive Disorder and Its Specifiers in the United States

IMPORTANCE

No US national data are available on the prevalence and correlates of DSM-5-defined major depressive disorder (MDD) or on MDD specifiers as defined in DSM-5.

OBJECTIVE

To present current nationally representative findings on the prevalence, correlates, psychiatric comorbidity, functioning, and treatment of DSM-5 MDD and initial information on the prevalence, severity, and treatment of DSM-5 MDD severity, anxious/distressed specifier, and mixed-features specifier, as well as cases that would have been characterized as bereavement in DSM-IV.

DESIGN, SETTING, AND PARTICIPANTS

In-person interviews with a representative sample of US noninstitutionalized civilian adults (≥18 years) (n = 36 309) who participated in the 2012-2013 National Epidemiologic Survey on Alcohol and Related Conditions III (NESARC-III). Data were collected from April 2012 to June 2013 and were analyzed in 2016-2017.

MAIN OUTCOMES AND MEASURES

Prevalence of DSM-5 MDD and the DSM-5 specifiers. Odds ratios (ORs), adjusted ORs (aORs), and 95% CIs indicated associations with demographic characteristics and other psychiatric disorders.

RESULTS

Of the 36 309 adult participants in NESARC-III, 12-month and lifetime prevalences of MDD were 10.4% and 20.6%, respectively. Odds of 12-month MDD were significantly lower in men (OR, 0.5; 95% CI, 0.46-0.55) and in African American (OR, 0.6; 95% CI, 0.54-0.68), Asian/Pacific Islander (OR, 0.6; 95% CI, 0.45-0.67), and Hispanic (OR, 0.7; 95% CI, 0.62-0.78) adults than in white adults and were higher in younger adults (age range, 18-29 years; OR, 3.0; 95% CI, 2.48-3.55) and those with low incomes ($19 999 or less; OR, 1.7; 95% CI, 1.49-2.04). Associations of MDD with psychiatric disorders ranged from an aOR of 2.1 (95% CI, 1.84-2.35) for specific phobia to an aOR of 5.7 (95% CI, 4.98-6.50) for generalized anxiety disorder. Associations of MDD with substance use disorders ranged from an aOR of 1.8 (95% CI, 1.63-2.01) for alcohol to an aOR of 3.0 (95% CI, 2.57-3.55) for any drug. Most lifetime MDD cases were moderate (39.7%) or severe (49.5%). Almost 70% with lifetime MDD had some type of treatment. Functioning among those with severe MDD was approximately 1 SD below the national mean. Among 12.9% of those with lifetime MDD, all episodes occurred just after the death of someone close and lasted less than 2 months. The anxious/distressed specifier characterized 74.6% of MDD cases, and the mixed-features specifier characterized 15.5%. Controlling for severity, both specifiers were associated with early onset, poor course and functioning, and suicidality.

CONCLUSIONS AND RELEVANCE

Among US adults, DSM-5 MDD is highly prevalent, comorbid, and disabling. While most cases received some treatment, a substantial minority did not. Much remains to be learned about the DSM-5 MDD specifiers in the general population.

Practical considerations in medical cannabis administration and dosing

Cannabis has been employed medicinally throughout history, but its recent legal prohibition, biochemical complexity and variability, quality control issues, previous dearth of appropriately powered randomised controlled trials, and lack of pertinent education have conspired to leave clinicians in the dark as to how to advise patients pursuing such treatment. With the advent of pharmaceutical cannabis-based medicines (Sativex/nabiximols and Epidiolex), and liberalisation of access in certain nations, this ignorance of cannabis pharmacology and therapeutics has become untenable. In this article, the authors endeavour to present concise data on cannabis pharmacology related to tetrahydrocannabinol (THC), cannabidiol (CBD) et al., methods of administration (smoking, vaporisation, oral), and dosing recommendations. Adverse events of cannabis medicine pertain primarily to THC, whose total daily dose-equivalent should generally be limited to 30mg/day or less, preferably in conjunction with CBD, to avoid psychoactive sequelae and development of tolerance. CBD, in contrast to THC, is less potent, and may require much higher doses for its adjunctive benefits on pain, inflammation, and attenuation of THC-associated anxiety and tachycardia. Dose initiation should commence at modest levels, and titration of any cannabis preparation should be undertaken slowly over a period of as much as two weeks. Suggestions are offered on cannabis-drug interactions, patient monitoring, and standards of care, while special cases for cannabis therapeutics are addressed: epilepsy, cancer palliation and primary treatment, chronic pain, use in the elderly, Parkinson disease, paediatrics, with concomitant opioids, and in relation to driving and hazardous activities.

Do medical marijuana laws reduce addictions and deaths related to pain killers?

Recent work finds that medical marijuana laws reduce the daily doses filled for opioid analgesics among Medicare Part-D and Medicaid enrollees, as well as population-wide opioid overdose deaths. We replicate the result for opioid overdose deaths and explore the potential mechanism. The key feature of a medical marijuana law that facilitates a reduction in overdose death rates is a relatively liberal allowance for dispensaries. As states have become more stringent in their regulation of dispensaries, the protective value generally has fallen. These findings suggest that broader access to medical marijuana facilitates substitution of marijuana for powerful and addictive opioids.

Willingness to Participate in Longitudinal Research Among People with Chronic Pain Who Take Medical Cannabis: A Cross-Sectional Survey

Background: Regulatory barriers limit clinical trials of medical cannabis in the United States. Longitudinal cohort studies may be one feasible alternative that could yield clinically relevant information. Willingness to participate in such studies is not known.

Materials and Methods: In October 2016, we surveyed a convenience sample of patients with chronic pain from two New York registered organizations (responsible for growing, processing, distributing, and retailing medical cannabis products). After a vignette describing a longitudinal cohort study involving weekly patient-reported outcomes and quarterly assessments of physical functioning and urine and blood tests, we asked about respondents' willingness to participate. We examined willingness to participate, duration of participation, and frequency of data collections overall and by subgroups, using multivariable logistic regression models.

Results: Of 405 respondents (estimated response rate: 30%), 54% were women and 81% were white non-Hispanic. Neuropathy was the most common pain condition (67%) followed by inflammatory bowel disease (19%). Of respondents, 94% (95% CI 92–97%) thought that the study should be done, 85% (95% CI 81–88%) would definitely or probably enroll if asked, 76% (95% CI 72–81%) would participate for ≥1 year, and 59% (95% CI 54–64%) would respond to questions at least daily. Older age was the only factor associated with lower willingness to participate, lower willingness to participate for ≥1 year, and lower willingness to respond to questions at least daily.

Conclusions: Nearly all respondents were supportive of the proposed study and most reported that they would enroll if asked. Enhanced engagement with older individuals may be needed to promote equal enrollment. Recruitment for longitudinal cohort studies with frequent data collection appears feasible in this patient population.

US Epidemiology of Cannabis Use and Associated Problems

This review provides an overview of the changing US epidemiology of cannabis use and associated problems. Adults and adolescents increasingly view cannabis as harmless, and some can use cannabis without harm. However, potential problems include harms from prenatal exposure and unintentional childhood exposure; decline in educational or occupational functioning after early adolescent use, and in adulthood, impaired driving and vehicle crashes; cannabis use disorders (CUD), cannabis withdrawal, and psychiatric comorbidity. Evidence suggests national increases in cannabis potency, prenatal and unintentional childhood exposure; and in adults, increased use, CUD, cannabis-related emergency room visits, and fatal vehicle crashes. Twenty-nine states have medical marijuana laws (MMLs) and of these, 8 have recreational marijuana laws (RMLs). Many studies indicate that MMLs or their specific provisions did not increase adolescent cannabis use. However, the more limited literature suggests that MMLs have led to increased cannabis potency, unintentional childhood exposures, adult cannabis use, and adult CUD. Ecological-level studies suggest that MMLs have led to substitution of cannabis for opioids, and also possibly for psychiatric medications. Much remains to be determined about cannabis trends and the role of MMLs and RMLs in these trends. The public, health professionals, and policy makers would benefit from education about the risks of cannabis use, the increases in such risks, and the role of marijuana laws in these increases.

How Medical Marijuana Smoothed the Transition to Marijuana Legalization in the United States

Public support for legalizing marijuana use increased from 25% in 1995 to 60% in 2016, rising in lockstep with support for same-sex marriage. Between November 2012 and November 2016, voters in eight states passed ballot initiatives to legalize marijuana sales for nonmedical purposes-covering one-fifth of the US population. These changes are unprecedented but are not independent of the changes in medical marijuana laws that have occurred over the past 20 years. This article suggests five ways in which the passage and implementation of medical marijuana laws smoothed the transition to nonmedical legalization in the United States: (a) They demonstrated the efficacy of using voter initiatives to change marijuana supply laws, (b) enabled the psychological changes needed to destabilize the "war on drugs" policy stasis, (c) generated an evidence base that could be used to downplay concerns about nonmedical legalization, (d) created a visible and active marijuana industry, and (e) revealed that the federal government would allow state and local jurisdictions to generate tax revenue from marijuana.

The use of cannabis in response to the opioid crisis: A review of the literature

BACKGROUND

A staggering number of Americans are dying from overdoses attributed to prescription opioid medications (POMs). In response, states are creating policies related to POM harm reduction strategies, overdose prevention, and alternative therapies for pain management, such as cannabis (medical marijuana). However, little is known about how the use of cannabis for pain management may be associated with POM use.

PURPOSE

The purpose of this article is to examine state medical cannabis (MC) use laws and policies and their potential association with POM use and related harms.

METHODS

A systematic literature review was conducted to explore United States policies related to MC use and the association with POM use and related harms. Medline, PubMed, CINAHL, and Cochrane databases were searched to identify peer-reviewed articles published between 2010 and 2017. Using the search criteria, 11,513 records were identified, with 789 abstracts reviewed, and then 134 full-text articles screened for eligibility.

FINDINGS

Of 134 articles, 10 articles met inclusion criteria. Four articles were cross-sectional online survey studies of MC substitution for POM, six were secondary data analyses exploring state-level POM overdose fatalities, hospitalizations related to MC or POM harms, opioid use disorder admissions, motor vehicle fatalities, and Medicare and Medicaid prescription cost analyses. The literature suggests MC laws could be associated with decreased POM use, fewer POM-related hospitalizations, lower rates of opioid overdose, and reduced national health care expenditures related to POM overdose and misuse. However, available literature on the topic is sparse and has notable limitations.

CONCLUSIONS

Review of the current literature suggests states that implement MC policies could reduce POM-associated mortality, improve pain management, and significantly reduce health care costs. However, MC research is constrained by federal policy restrictions, and more research related to MC as a potential alternative to POM for pain management, MC harms, and its impact on POM-related harms and health care costs should be a priority of public health, medical, and nursing research.

New product trial, use of edibles, and unexpected highs among marijuana and hashish users in Colorado

OBJECTIVE

This study examines the relationships between trial of new marijuana or hashish products and unexpected highs, and use of edible products and unexpected highs.

METHODS

We conducted an online survey of 634 adult, past-year marijuana users in Colorado. We used logistic regression models to examine the relationship between new product trial or edible use and unexpected highs.

RESULTS

In the first year that recreational marijuana was legal in Colorado, 71.4% of respondents tried a new marijuana or hashish product, and 53.6% used an edible product. Trial of new products was associated with greater odds of experiencing an unexpected high after controlling for age, gender, education, mental health status, current marijuana or hashish use, and mean amount of marijuana or hashish consumed in the past month (OR=2.13, p<0.001). Individuals who reported having used edibles had greater odds of experiencing an unexpected high, after controlling for the same set of variables (OR=1.56, p<0.05).

CONCLUSION

People who try new marijuana or hashish products, or use edible marijuana or hashish products, are at greater risk for an unexpected high. It is possible that some negative outcomes associated with marijuana use and unexpected highs may be averted through a better understanding of how to use product packaging to communicate with consumers.