The impact of medical and recreational marijuana laws on opioid prescribing in employer-sponsored health insurance

United States marijuana legalization and opioid mortality trends before and during the first year of the COVID-19 pandemic

BACKGROUND

To determine if marijuana legalization was associated with reduced opioid mortality.

STUDY DESIGN

The United States (US) opioid mortality trend during the 2010-2019 decade was compared in states and District of Columbia (jurisdictions) that had implemented marijuana legalization with states that had not. Acceleration of opioid mortality during 2020, the first year of the coronavirus disease 2019 (COVID-19) pandemic, was also compared in recreational and medicinal-only legalizing jurisdictions.

METHODS

Joinpoint methodology was applied to the Centers for Disease Control and Prevention WONDER data. Trends in legalizing jurisdictions were cumulative aggregates.

RESULTS

The overall opioid and fentanyl death rates and the percentage of opioid deaths due to fentanyl increased more during 2010-2019 in jurisdictions that legalized marijuana than in those that did not (pairwise comparison p = 0.007, 0.05, and 0.006, respectively). By 2019, the all-opioid and fentanyl death rates were 44 and 50 percent greater in the legalizing than in the nonlegalizing jurisdictions, respectively. When the COVID-19 pandemic hit in 2020, jurisdictions that implemented recreational marijuana legalization before 2019 had significantly greater increases in both overall opioid and fentanyl death rates than jurisdictions with medicinal-only legalization. For all-opioids, the mean (95 percent confidence interval) 2019-to-2020 increases were 46.5 percent (36.6, 56.3 percent) and 29.1 percent (20.2, 37.9 percent), respectively (p = 0.02). For fentanyl, they were 115.6 percent (80.2, 151.6 percent) and 55.4 percent (31.6, 79.2 percent), respectively (p = 0.01).

CONCLUSIONS

During the past decade, marijuana legalization in the US was associated at the jurisdiction level with a greater acceleration in opioid death rate. An even greater increase in opioid mortality occurred in recreational-legalizing jurisdictions with the onset of the COVID-19 pandemic. Marijuana legalization is correlated with worsening of the US opioid epidemic.

Characteristics of patients with non-cancer pain and long-term prescription opioid use who have used medical versus recreational marijuana

OBJECTIVE

Marijuana use is increasingly common among patients with chronic non-cancer pain (CNCP) and long-term opioid therapy (LTOT). We determined if lifetime recreational and medical marijuana use were associated with more frequent and higher dose prescription opioid use.

DESIGN

Cross-sectional SUBJECTS: Eligible patients (n=1,037), who had a new period of prescription opioid use lasting 30-90 days, were recruited from two midwestern health care systems to a study of long-term prescription opioid use and mental health outcomes. The present cross-sectional analyses uses baseline data from this on-going cohort study.

METHODS

Primary exposures were participant reported lifetime recreational and medical marijuana use versus no lifetime marijuana use. Prescription opioid characteristics included daily versus non-daily opioid use and ≥50 morphine milligram equivalent (MME) dose per day vs. <50 MME. Multivariate, logistic regression models estimated the association between lifetime recreational and medical marijuana use vs. no use and odds of daily and higher dose prescription opioid use, before and after adjusting for confounding.

RESULTS

The sample was an average of 54.9 (SD±11.3) years of age, 57.3% identified as female gender, 75.2% identified as White, and 22.5% identified as Black race. Among all participants, 44.4% were never marijuana users, 21.3% were recreational only, 7.7% medical only and 26.6% were both recreational and medical marijuana users. After controlling for all confounders, lifetime recreational marijuana use, as compared to no use, was significantly associated with increased odds of daily prescription opioid use (OR=1.61; 95%CI:1.02-2.54). There was no association between lifetime recreational or medical marijuana use and daily opioid dose.

CONCLUSION

Lifetime medical marijuana use is not linked to current opioid dose, but lifetime recreational use is associated with more than a 60% odds of being a daily prescription opioid user. Screening for lifetime recreational marijuana use may identify patients with chronic pain who are vulnerable to daily opioid use which increases risk for adverse opioid outcomes. Prospective data is needed to determine how marijuana use influences the course of LTOT and vice versa.

Recreational and Medical Cannabis Legalization and Opioid Prescriptions and Mortality

Importance

While some have argued that cannabis legalization has helped to reduce opioid-related morbidity and mortality in the US, evidence has been mixed. Moreover, existing studies did not account for biases that could arise when policy effects vary over time or across states or when multiple policies are assessed at the same time, as in the case of recreational and medical cannabis legalization.

Objective

To quantify changes in opioid prescriptions and opioid overdose deaths associated with recreational and medical cannabis legalization in the US.

Design, Setting, and Participants

This quasiexperimental, generalized difference-in-differences analysis used annual state-level data between January 2006 and December 2020 to compare states that legalized recreational or medical cannabis vs those that did not.

Intervention

Recreational and medical cannabis law implementation (proxied by recreational and medical cannabis dispensary openings) between 2006 and 2020 across US states.

Main Outcomes and Measures

Opioid prescription rates per 100 persons and opioid overdose deaths per 100 000 population based on data from the US Centers for Disease Control and Prevention.

Results

Between 2006 and 2020, 13 states legalized recreational cannabis and 23 states legalized medical cannabis. There was no statistically significant association of recreational or medical cannabis laws with opioid prescriptions or overall opioid overdose mortality across the 15-year study period, although the results also suggested a potential reduction in synthetic opioid deaths associated with recreational cannabis laws (4.9 fewer deaths per 100 000 population; 95% CI, -9.49 to -0.30; P = .04). Sensitivity analyses excluding state economic indicators, accounting for additional opioid laws and using alternative ways to code treatment dates yielded substantively similar results, suggesting the absence of statistically significant associations between cannabis laws and the outcomes of interest during the full study period.

Conclusions and Relevance

The results of this study suggest that, after accounting for biases due to possible heterogeneous effects and simultaneous assessment of recreational and medical cannabis legalization, the implementation of recreational or medical cannabis laws was not associated with opioid prescriptions or opioid mortality, with the exception of a possible reduction in synthetic opioid deaths associated with recreational cannabis law implementation.

Adult Medical Cannabinoid Use and Changes in Prescription Controlled Substance Use

Introduction: Nonopioid-based strategies for managing chronic noncancer pain are needed to help reduce overdose deaths. Although lab studies and population-level data suggest that cannabinoids could provide opioid-sparing effects, among medical cannabis participants they may also impact overdose risk by modifying other controlled substance use such as sedative hypnotics. However, no study has combined observational data at the individual level to empirically address interactions between the use of cannabinoids and prescribed controlled substances. Methods: Electronic health records, including prescription drug monitoring program data, from a large multisite medical cannabis program in New York State were abstracted for all participants with noncancer pain and recently prescribed noncannabinoid controlled substances who completed a new intake visit from April 15, 2018-April 14, 2019 and who remained actively in treatment for >180 days. Participants were partitioned into two samples: those with recent opioid use and those with active opioid use and co-use of sedative hypnotics. A patient-month level analysis assessed total average equivalent milligrams by class of drug (i.e., cannabinoid distinguishing tetrahydrocannabinol [THC] vs. cannabidiol [CBD], opioids, and sedative-hypnotics) received as a time-varying outcome measure across each 30-day "month" period postintake for at least 6 months for all participants. Results: Sample 1 of 285 opioid users were 61.1 years of age (±13.5), 57.5% female, and using an average of 49.7 (±98.5) morphine equivalents daily at intake. Unadjusted analyses found a modest decline in morphine equivalents to 43.9 mg (±94.1 mg) from 49.7 (±98.5) in month 1 (p=0.047) while receiving relatively low doses of THC (2.93 mg/day) and CBD (2.15 mg/day). Sample 2 of 95 opioid and sedative-hypnotic users were 60.9 years of age (±13.1), 63.2% female, and using an average of 86.6 (±136.2) morphine equivalents daily, and an average of 4.3 (±5.6) lorazepam equivalents. Unadjusted analyses did not find significant changes in either morphine equivalents (p=0.81) or lorazepam equivalents (p=0.980), and patients similarly received relatively low doses of THC (2.32 mg/day) and CBD (2.24 mg/day). Conclusions: Findings demonstrated minimal to no change in either opioids or sedative hypnotics over the 6 months of medical cannabis use but may be limited by low retention rates, external generalizability, and an inability to account for nonprescribed substance use.

Impact of Recreational Cannabis Legalization on Opioid Prescribing and Opioid-Related Hospital Visits in Colorado: an Observational Study

BACKGROUND

Cannabis may be a substitute for opioids but previous studies have found conflicting results when using data from more recent years. Most studies have examined the relationship using state-level data, missing important sub-state variation in cannabis access.

OBJECTIVE

To examine cannabis legalization on opioid use at the county level, using Colorado as a case study. Colorado allowed recreational cannabis stores in January 2014. Local communities could decide whether to allow dispensaries, creating variation in the level of exposure to cannabis outlets.

DESIGN

Observational, quasi-experimental design exploiting county-level variation in allowance of recreational dispensaries.

SUBJECTS

Colorado residents MEASURES: We use licensing information from the Colorado Department of Revenue to measure county-level exposure to cannabis outlets. We use the state's Prescription Drug Monitoring Program (2013-2018) to construct opioid-prescribing measures of number of 30-day fills and total morphine equivalents, both per county resident per quarter. We construct outcomes of opioid-related inpatient visits (2011-2018) and emergency department visits (2013-2018) with Colorado Hospital Association data. We use linear models in a differences-in-differences framework that accounts for the varying exposure to medical and recreational cannabis over time. There are 2048 county-quarter observations used in the analysis.

RESULTS

We find mixed evidence of cannabis exposure on opioid-related outcomes at the county level. We find increasing exposure to recreational cannabis is associated with a statistically significant decrease in number of 30-day fills (coefficient: -117.6, p-value<0.01) and inpatient visits (coefficient: -0.8, p-value: 0.03), but not total MME nor ED visits. Counties with no medical exposure prior to recreational legalization experience greater reductions in the number of 30-day fills and MME than counties with prior medical exposure (p=0.02 for both).

CONCLUSIONS

Our mixed findings suggest that further increases in cannabis beyond medical access may not always reduce opioid prescribing or opioid-related hospital visits at a population level.

Self-reported Medicinal Cannabis Use as an Alternative to Prescription and Over-the-counter Medication Use Among US Military Veterans

BACKGROUND

Mental and other physical health concerns and substance use disorder are common and co-occurring events experienced by US veterans. Treatment with medicinal cannabis is a potential alternative to unwanted medication use for veterans, but more clinical and epidemiologic research is needed to understand the risks and benefits.

METHODS

Data were collected from a cross-sectional, self-reported, anonymous survey asking US veterans about their health conditions, medical treatments, demographics, and medicinal cannabis use along with its self-reported effectiveness. In addition to descriptive statistics, logistic regression models were run to examine correlates of the use of cannabis as a substitution for prescription or over-the-counter medications.

FINDINGS

A total of 510 veterans of US military service participated in the survey, which was administered between March 3 and December 31, 2019. The participants reported experiencing a variety of mental and other physical health conditions. Primary health conditions reported included chronic pain (196; 38%), PTSD (131; 26%), anxiety (47; 9%), and depression (26; 5%). Most participants (343; 67%) reported using cannabis daily. Many reported using cannabis to reduce the use of over-the-counter medications (151; 30%) including antidepressants (130; 25%), anti-inflammatories (89; 17%), and other prescription medications. Additionally, 463 veterans (91% of respondents) reported that medical cannabis helped them to experience a greater quality of life and 105 (21%) reported using fewer opioids as a result of their medical cannabis use. Veterans who were Black, who were female, who served in active combat, and who were living with chronic pain were more likely to report a desire to reduce the number of prescription medications they were taking (odds ratios = 2.92, 2.29, 1.79, and 2.30, respectively). Women and individuals who used cannabis daily were more likely to report active use of cannabis to reduce prescription medication use (odds ratios = 3.05 and 2.26).

IMPLICATIONS

Medicinal cannabis use was reported to improve quality of life and reduce unwanted medication use by many of the study participants. The present findings indicate that medicinal cannabis can potentially play a harm-reduction role, helping veterans to use fewer pharmaceutical medications and other substances. Clinicians should be mindful of the potential associations between race, sex, and combat experience and the intentions for and frequency of medicinal cannabis use.

Recreational cannabis and opioid distribution

Twenty-one U.S. states have passed recreational cannabis laws as of November 2022. Cannabis may be a substitute for prescription opioids in the treatment of chronic pain. Previous studies have assessed recreational cannabis laws' effects on opioid prescriptions financed by specific private or public payers or dispensed to a unique endpoint. Our study adds to the literature in three important ways: by (1) examining these laws' impacts on prescription opioid dispensing across all payers and endpoints, (2) adjusting for important opioid-related policies such as opioid prescribing limits, and (3) modeling opioids separately by type. We implement two-way fixed-effects regressions and leverage variation from eleven U.S. states that adopted a recreational cannabis law (RCL) between 2010 and 2019. We find that RCLs lead to a reduction in codeine dispensed at retail pharmacies. Among prescription opioids, codeine is particularly likely to be used non-medically. Thus, the finding that RCLs appear to reduce codeine dispensing is potentially promising from a public health perspective.

Endogenous opiates and behavior: 2021

This paper is the forty-fourth consecutive installment of the annual anthological review of research concerning the endogenous opioid system, summarizing articles published during 2021 that studied the behavioral effects of molecular, pharmacological and genetic manipulation of opioid peptides and receptors as well as effects of opioid/opiate agonizts and antagonists. The review is subdivided into the following specific topics: molecular-biochemical effects and neurochemical localization studies of endogenous opioids and their receptors (1), the roles of these opioid peptides and receptors in pain and analgesia in animals (2) and humans (3), opioid-sensitive and opioid-insensitive effects of nonopioid analgesics (4), opioid peptide and receptor involvement in tolerance and dependence (5), stress and social status (6), learning and memory (7), eating and drinking (8), drug abuse and alcohol (9), sexual activity and hormones, pregnancy, development and endocrinology (10), mental illness and mood (11), seizures and neurologic disorders (12), electrical-related activity and neurophysiology (13), general activity and locomotion (14), gastrointestinal, renal and hepatic functions (15), cardiovascular responses (16), respiration and thermoregulation (17), and immunological responses (18).

The clouded debate: A systematic review of comparative longitudinal studies examining the impact of recreational cannabis legalization on key public health outcomes

Background

Ineffective cannabis regulatory frameworks such as prohibition have sparked interest in alternative solutions to reduce individual and societal harms. While it has been suggested that the recreational legalization process has yielded early successes, the relatively recent implementation of the novel policies has provided a modest time frame for a truly thorough establishment and assessment of key population-level indicators. The following systematic review focuses on identifying the downstream public health sequelae of cannabis legalization policies, including parameters such as cannabis consumption rates, hospitalization rates, vehicular accidents and fatalities, criminal activity, and suicidal behaviors, as well as other substance use trends.

Methods

An exhaustive search of the MEDLINE and Google Scholar databases were performed to identify high-quality (1) longitudinal studies, which (2) compared key public health outcomes between regions which had and had not implemented recreational cannabis legalization (RML) policies, (3) using distinct databases and/or time frames. Thirty-two original research articles were retained for review.

Results

Adult past-month cannabis consumption (26+ years) seems to have significantly increased following RML, whereas young adult (18-26 years) and adolescent (12-17 years) populations do not show a significant rise in past-month cannabis use. RML shows preliminary trends in increasing service use (such as hospitalizations, emergency department visits, or poisonings) or vehicular traffic fatalities. Preliminary evidence suggests that RML is related to potential increases in serious/violent crimes, and heterogeneous effects on suicidal behaviors. While the research does not illustrate that RML is linked to changing consumptions patterns of cigarette, stimulant, or opioid use, alcohol use may be on the rise, and opioid prescribing patterns are shown to be significantly correlated with RML.

Conclusion

The current data supports the notion that RML is correlated with altered cannabis consumption in adults, potentially increased criminal activity, and a decline in opioid quantities and prescriptions provided to patients. Future work should address additional knowledge gaps for vulnerable populations, such as individuals with mental health problems or persons consuming cannabis frequently/at higher THC doses. The effects of varying legalization models should also be evaluated for their potentially differing impacts on population-level outcomes.

Recreational cannabis legalizations associated with reductions in prescription drug utilization among Medicaid enrollees

The potential substitution of cannabis for prescription medication has attracted a substantial amount of attention within the context of medical cannabis laws (MCLs). However, much less is known about the association between recreational cannabis laws (RCLs) and prescription drug use. With recent evidence supporting substitution of cannabis for prescription drugs following MCLs, it is reasonable to ask what effect RCLs may have on those outcomes. We use quarterly data for all Medicaid prescriptions from 2011 to 2019 to investigate the effect of state-level RCLs on prescription drug utilization. We estimate this effect with a series of two-way fixed effects event study models. We find significant reductions in the volume of prescriptions within the drug classes that align with the medical indications for pain, depression, anxiety, sleep, psychosis, and seizures. Our results suggest substitution away from prescription drugs and potential cost savings for state Medicaid programs.

Societal Costs and Outcomes of Medical and Recreational Marijuana Policies in the United States: A Systematic Review

Significant support exists in the United States for legalization of marijuana/cannabis. As of 2021, 36 states and four territories approved the legalization of medical cannabis via medical marijuana laws (MMLs), and 15 states and District of Columbia (DC) have adopted recreational marijuana laws (RMLs). We performed structured and systematic searches of articles published from 2010 through September 2021. We assess the literature pertaining to adolescent marijuana use; opioid use and opioid-related outcomes; alcohol use; tobacco use; illicit and other drug use; marijuana growing and cultivation; employment, earnings, and other workplace outcomes; academic achievement and performance; criminal activity; perceived harmfulness; traffic and road safety; and suicide and sexual activity. Overall, 113 articles satisfied our inclusion criteria. Except for opioids, studies on use of other substances (illicit drugs, tobacco, and alcohol) were inconclusive. MMLs and RMLs do not generate negative outcomes in the labor market, lead to greater criminal activity, or reduce traffic and road safety.

Association between fatal opioid overdose and state medical cannabis laws in US national survey data, 2000-2011

AIMS

Most information on the relationship between medical cannabis laws (MCL) and the risk for opioid overdose fatality has been based on studies with ecological designs. To contribute additional information, we used a novel case-control design and individual-level data from national surveys to assess whether state medical cannabis laws were associated with reduced risk of fatal opioid overdose between 2000-2011.

METHODS

Data from participants surveyed in the National Health Interview Survey (NHIS) between 1986-2011 were included. For those sampled between 1986-2009, detailed mortality follow-up data were available from the National Death Index up to 12/31/2011. Opioid overdose decedents (n = 791) were classified as cases. Between 2000-2011, all cases arising in a given year were matched to adult controls who were surveyed the same year and eligible for mortality follow-up (n = 723,920). The distribution of exposure to state MCL was contrasted between cases and controls, providing an approximation of the rate ratio of fatal opioid overdose associated with MCLs. Due to a NHIS sample redesign, we stratified analysis using timeframes before and after 2005.

RESULTS

Overall, compared to controls, cases were more likely to be male, middle-aged, non-Hispanic White, separated/divorced; less educated, and have a family income below the poverty threshold. No overall association between state MCLs and the rate of opioid overdose was observed between 2000-2005 (aOR = 1.22, 95% CI: 0.83-1.79) or between 2006-2011 (aOR = 0.87, 95% CI: 0.60-1.25). No significant difference between sampling timeframes was observed (ratio of aOR's = 0.71, 95% CI: 0.49-1.01).

CONCLUSIONS

We found no overall protective relationship between state MCLs and opioid overdose. Future research with more recent mortality data and more refined cannabis policy classifications would be useful. The importance of the study is two-fold. First, the findings provide an additional source of information countering claims of a protective effect of MCLs on opioid overdoses, suggesting that other solutions to the opioid overdose crisis are needed. Second, the study offers a potentially useful design to answer important population-level public health questions.

Recreational cannabis laws and opioid-related emergency department visit rates

The opioid epidemic in the United States has accelerated during the COVID-19 pandemic. As of 2021, roughly a third of Americans now live in a state with a recreational cannabis law (RCL). Recent evidence indicates RCLs could be a harm reduction tool to address the opioid epidemic. Individuals may use cannabis to manage pain, as well as to relieve opioid withdrawal symptoms, though it does not directly treat opioid use disorder. It is thus unclear whether RCLs are an effective policy tool to reduce adverse opioid-related health outcomes. In this study, we examine the impact of RCLs on a key opioid-related adverse health outcome: opioid-related emergency department (ED) visit rates. We estimate event study models using nearly comprehensive ED data from 29 states from 2011 to 2017. We find that RCLs reduce opioid-related ED visit rates by roughly 7.6% for two quarters after implementation. These effects are driven by men and adults aged 25-44. These effects dissipate after 6 months. Our estimates indicate RCLs did not increase opioid-related ED visits. We conclude that, while cannabis liberalization may offer some help in curbing the opioid epidemic, it is likely not a panacea.