Mental Health-related Emergency Department Visits Associated With Cannabis in Colorado

The impact of recreational cannabis legalization on youth: the Colorado experience

Over the past two decades, cannabis policies have liberalized in the United States, culminating in the legalization of recreational cannabis in Colorado and Washington state in 2012. This review will focus on the impact of recreational cannabis legalization in Colorado. While the prevalence of past-year and past-month cannabis use has remained relatively steady among adolescents post-legalization, the prevalence of young adult use has continued to rise. Cannabis products with increased potency have become more prevalent and widely used. There are concerns that the use of products with increased potency will increase risk for cannabis use and comorbid mental health disorders, particularly cannabis-induced psychosis and suicidal behavior, although more research is needed to fully understand the impact of high-potency products. Since the legalization of recreational cannabis, numerous additional public health concerns have emerged: unintentional overdoses requiring acute care visits, electronic vaping-associated lung injury, increased motor vehicle collisions related to cannabis consumption, and higher rates of cannabis use during pregnancy. Lessons learned from the first decade of cannabis legalization emphasize the need for research efforts to provide evidence-based guidelines, inform prevention strategies, and implement selective interventions for at-risk populations including youth, individuals with comorbid mental health disorders, and individuals who are pregnant.

Impact of non-medical cannabis legalization with market restrictions on health service use and incident cases of psychotic disorder in Ontario, Canada

BACKGROUND

Cannabis is a risk factor in the onset and persistence of psychotic disorders. There is concern that non-medical cannabis legalization in Canada may have population-level impacts on psychotic disorders. We sought to examine changes in health service use and incident cases of psychotic disorder following cannabis legalization, during a period of tight restrictions on retail stores and product types.

METHODS

We conducted a cross-sectional interrupted time-series analysis using linked population-based health administrative data from Ontario (Canada) from January 2014 to March 2020. We identified psychosis-related outpatient visits, emergency department visits, hospitalizations, and inpatient length of stay, as well as incident cases of psychotic disorders, among people aged 14 to 60 years.

RESULTS

We did not find evidence of increases in health service use or incident cases of psychotic disorders over the short-term (17 month) period following cannabis legalization. However, we found clear increasing trends in health service use and incident cases of substance-induced psychotic disorders over the entire observation window (2014-2020).

CONCLUSION

Our findings suggest that the initial period of tight market restriction following legalization of non-medical cannabis was not associated with an increase in health service use or frequency of psychotic disorders. A longer post-legalization observation period, which includes expansion of the commercial cannabis market, is needed to fully understand the population-level impacts of non-medical cannabis legalization; thus, it would be premature to conclude that the legalization of non-medical cannabis did not lead to increases in health service use and incident cases of psychotic disorder.

Impact of Cannabis Legalization on Adolescent Cannabis Use

Because of substantial limitations in available national data, such as inconsistencies among surveys and small sample sizes, the increased prevalence of cannabis use among adolescents since recreational legalization has not been directly observed. Nevertheless, both usage frequency and product potency have significantly increased, alongside alternative routes of delivery to smoking, such as vaping cannabis. Moreover, certain populations may be especially vulnerable to the effects of legalization. Regardless of differing state-level cannabis legalization status, the adverse consequences of cannabis on youth have clear negative impacts on mental health, medical symptoms, educational outcomes, and increased risk of addiction to other substances.

Disparities in cannabis-related emergency department visits across depressed and non-depressed individuals and the impact of recreational cannabis policy in Ontario, Canada

BACKGROUND

Recreational cannabis policies are being considered in many jurisdictions internationally. Given that cannabis use is more prevalent among people with depression, legalisation may lead to more adverse events in this population. Cannabis legalisation in Canada included the legalisation of flower and herbs (phase 1) in October 2018, and the deregulation of cannabis edibles one year later (phase 2). This study investigated disparities in cannabis-related emergency department (ED) visits in depressed and non-depressed individuals in each phase.

METHODS

Using administrative data, we identified all adults diagnosed with depression 60 months prior to legalisation (n = 929 844). A non-depressed comparison group was identified using propensity score matching. We compared the pre-post policy differences in cannabis-related ED-visits in depressed individuals v. matched (and unmatched) non-depressed individuals.

RESULTS

In the matched sample (i.e. comparison with non-depressed people similar to the depressed group), people with depression had approximately four times higher risk of cannabis-related ED-visits relative to the non-depressed over the entire period. Phases 1 and 2 were not associated with any changes in the matched depressed and non-depressed groups. In the unmatched sample (i.e. comparison with the non-depressed general population), the disparity between individuals with and without depression is greater. While phase 1 was associated with an immediate increase in ED-visits among the general population, phase 2 was not associated with any changes in the unmatched depressed and non-depressed groups.

CONCLUSIONS

Depression is a risk factor for cannabis-related ED-visits. Cannabis legalisation did not further elevate the risk among individuals diagnosed with depression.

Cannabis-Induced Anxiety Disorder in the Emergency Department

BACKGROUND

In December 2018, Michigan became the 10th state to legalize marijuana for adults. Since this law took effect, increased availability and use of cannabis in Michigan have led to increased emergency department (ED) visits associated with the drug's psychiatric effects.

OBJECTIVES

To describe cannabis-induced anxiety disorder's prevalence, clinical features, and disposition in a community-based study.

METHODS

This was a retrospective cohort analysis of consecutive patients diagnosed with acute toxicity related to cannabis use (ICD-10 code F12). Patients were seen at seven EDs over a 24-month study period. Data collected included demographics, clinical features, and treatment outcomes in ED patients who met the criteria for cannabis-induced anxiety disorder. This group was compared to a cohort experiencing other forms of acute cannabis toxicity. Chi-squared and t-tests were used to compare these two groups across key demographic and outcome variables.

RESULTS

During the study period, 1135 patients were evaluated for acute cannabis toxicity. A total of 196 patients (17.3%) had a chief complaint of anxiety, and 939 (82.7%) experienced other forms of acute cannabis toxicity, predominantly symptoms of intoxication or cannabis hyperemesis syndrome. Patients with anxiety symptoms had panic attacks (11.7%), aggression or manic behavior (9.2%), and hallucinations (6.1%). Compared to patients presenting with other forms of cannabis toxicity, those with anxiety were likelier to be younger, ingested edible cannabis, had psychiatric comorbidities, or had a history of polysubstance abuse.

CONCLUSIONS

Cannabis-induced anxiety occurred in 17.3% of ED patients in this community-based study. Clinicians must be adept in recognizing, evaluating, managing, and counseling these patients following cannabis exposure.

Cannabis positivity rates in 17 emergency departments across the United States with varying degrees of marijuana legalization

BACKGROUND

Many states in the United States have progressed towards legalization of marijuana including decriminalization, medicinal and/or recreational use. We studied the impact of legalization on cannabis-related emergency department visits in states with varying degrees of legalization.

METHODS

Seventeen healthcare institutions in fifteen states (California, Colorado, Connecticut, Florida, Iowa, Kentucky, Maryland, Massachusetts, Missouri, New Hampshire, Oregon, South Carolina, Tennessee, Texas, Washington) participated. Cannabinoid immunoassay results and cannabis-related International Classification of Diseases (ninth and tenth versions) codes were obtained for emergency department visits over a 3- to 8-year period during various stages of legalization: no state laws, decriminalized, medical approval before dispensaries, medical dispensaries available, recreational approval before dispensaries and recreational dispensaries available. Trends and monthly rates of cannabinoid immunoassay and cannabis-related International Classification of Diseases code positivity were determined during these legalization periods.

RESULTS

For most states, there was a significant increase in both cannabinoid immunoassay and International Classification of Diseases code positivity as legalization progressed; however, positivity rates differed. The availability of dispensaries may impact positivity in states with medical and/or recreational approval. In most states with no laws, there was a significant but smaller increase in cannabinoid immunoassay positivity rates.

CONCLUSIONS

States may experience an increase in cannabis-related emergency department visits with progression toward marijuana legalization. The differences between states, including those in which no impact was seen, are likely multifactorial and include cultural norms, attitudes of local law enforcement, differing patient populations, legalization in surrounding states, availability of dispensaries, various ordering protocols in the emergency department, and the prevalence of non-regulated cannabis products.

Trends in emergency department visits associated with cannabis use among older adults in California, 2005-2019

BACKGROUND

The use of cannabis among older adults is increasing in the United States. While cannabis use has been suggested to help alleviate chronic symptoms experienced by older adults, its potential adverse effects may lead to unintended consequences, including increased acute healthcare utilization related to its use. The objective of this study was to examine trends in cannabis-related emergency department (ED) visits in California.

METHODS

Using data from the Department of Healthcare Access and Information, we conducted a trend analysis of cannabis-related ED visits from all acute care hospitals in California from 2005 to 2019. For each calendar year, we determined the cannabis-related ED visit rate per 100,000 ED visits for adults aged ≥65 utilizing primary or secondary diagnosis codes. We estimated the absolute and relative changes in overall cannabis-related visit rates during the study period and by subgroup, including age (65-74, 75-84, ≥85), race/ethnicity, sex, payer/insurance, Charlson comorbidity index score, and cannabis-related diagnosis code.

RESULTS

The cannabis-related ED visit rate increased significantly for adults aged ≥65 and all subgroups (p < 0.001). The overall rate increased from 20.7 per 100,000 visits in 2005 to 395.0 per 100,000 ED visits in 2019, a 1804% relative increase. By race/ethnicity, older Black adults had the highest ED visit rate in 2019 and the largest absolute increase while older males had a higher ED visit rate in 2019 and a greater absolute increase than older women. Older adults with a higher Charlson score had a higher ED visit rate in 2019 and a larger absolute increase during the study period.

CONCLUSION

Cannabis-related ED visits are increasing among older adults in California and are an adverse effect of cannabis use. Asking about cannabis use and providing education about its use should be a part of routine medical care for older adults.

Perceptions and Practices of Cannabis Use Among Emergency Department Patients

BACKGROUND

Nationally, in states where cannabis has been legalized, increases in cannabis-related hospitalizations and emergency department (ED) visits have also been observed.

OBJECTIVES

This study aims to: 1) Describe the sociodemographic characteristics of cannabis users presenting to two academic EDs in California; 2) Assess cannabis-related behaviors; 3) Assess perceptions of cannabis; 4) Identify and describe reasons for cannabis-related ED utilization.

METHODS

This is a cross-sectional study of patients visiting one of two academic EDs between February 16, 2018 and November 21, 2020. Eligible participants completed a novel questionnaire developed by the authors. Basic descriptive statistics, Pearson correlation coefficients, and logistic regression were used for statistical analysis of responses.

RESULTS

The questionnaire was completed by 2577 patients. A quarter were categorized as Current Users (n = 628, 24.4%). Current, Regular Users were evenly divided across gender, were relatively younger (18-34 years, 48.1%), and were largely non-Hispanic Caucasian. Over half of all respondents believed that the use of cannabis was less harmful than tobacco or alcohol use (n = 1537, 59.6%). One in five Current Users (n = 123, 19.8%) reported driving while using cannabis in the past month. A small proportion (n = 24, 3.9%) of Current Users reported ever visiting the ED for a cannabis-related chief complaint.

CONCLUSIONS

Overall, many ED patients are currently using cannabis; few report utilizing the ED due to cannabis-related problems. Current, Irregular Users may represent the ideal target group for ED-based educational efforts aimed at improving knowledge of safe cannabis use.

Impact of Cannabis Legalization on Adolescent Cannabis Use

Because of substantial limitations in available national data, such as inconsistencies among surveys and small sample sizes, the increased prevalence of cannabis use among adolescents since recreational legalization has not been directly observed. Nevertheless, both usage frequency and product potency have significantly increased, alongside alternative routes of delivery to smoking, such as vaping cannabis. Moreover, certain populations may be especially vulnerable to the effects of legalization. Regardless of differing state-level cannabis legalization status, the adverse consequences of cannabis on youth have clear negative impacts on mental health, medical symptoms, educational outcomes, and increased risk of addiction to other substances.

Psychiatric Emergencies in Los Angeles County During, and After, Initial COVID-19 Societal Restrictions: An Interrupted Time-Series Analysis

Emergency department (ED) visits for psychiatric care in the US reportedly declined during the COVID-19 pandemic. This work, however, does not control for strong temporal patterning in visits before the pandemic and does not examine a potential "rebound" in demand for psychiatric care following the relaxation of initial societal restrictions. Here, we examine COVID-19-related perturbations in psychiatric care during and after the 1st stage of societal restrictions in the largest safety-net hospital in Los Angeles. We retrieved psychiatric ED visit data (98,888 total over 156 weeks, Jan 2018 to Dec 2020) from Los Angeles County + USC Medical Center. We applied interrupted time series methods to identify and control for autocorrelation in psychiatric ED visits before examining their relation with the 1st stage of societal restrictions (i.e., March 13 to May 8, 2020), as well as the subsequent "rebound" period of relaxed restrictions (i.e., after May 8, 2020). Psychiatric ED visits fell by 78.13 per week (i.e., 12%) during the 1st stage of societal restrictions (SD = 23.99, p < 0.01). Reductions in ED visits for alcohol use, substance use, and (to a lesser extent) anxiety disorders accounted for the overall decline. After the 1st stage of societal restrictions, however, we observe no "rebound" above expected values in psychiatric ED visits overall (coef = - 16.89, SD = 20.58, p = 0.41) or by diagnostic subtype. This pattern of results does not support speculation that, at the population level, foregoing ED care during initial societal restrictions subsequently induced a psychiatric "pandemic" of urgent visits.

Consensus paper of the WFSBP task force on cannabis, cannabinoids and psychosis

OBJECTIVES

The liberalisation of cannabis laws, the increasing availability and potency of cannabis has renewed concern about the risk of psychosis with cannabis.

METHODS

The objective of the WFSBP task force was to review the literature about this relationship.

RESULTS

Converging lines of evidence suggest that exposure to cannabis increases the risk for psychoses ranging from transient psychotic states to chronic recurrent psychosis. The greater the dose, and the earlier the age of exposure, the greater the risk. For some psychosis outcomes, the evidence supports some of the criteria of causality. However, alternate explanations including reverse causality and confounders cannot be conclusively excluded. Furthermore, cannabis is neither necessary nor sufficient to cause psychosis. More likely it is one of the multiple causal components. In those with established psychosis, cannabis has a negative impact on the course and expression of the illness. Emerging evidence also suggests alterations in the endocannabinoid system in psychotic disorders.

CONCLUSIONS

Given that exposure to cannabis and cannabinoids is modifiable, delaying or eliminating exposure to cannabis or cannabinoids, could potentially impact the rates of psychosis related to cannabis, especially in those who are at high risk for developing the disorder.

Cannabinoid Poisoning-Related Emergency Department Visits and Inpatient Hospitalizations in Kentucky, 2017 to 2019

Background and objectives: Cannabis is the most used federally illicit substance. Due to widespread medicinal use and state-level legalization, public perceptions of cannabis have shifted toward the assumption that cannabis is safe. However, cannabinoids can cause adverse medical complications that may lead people to seek treatment. This study characterized cannabinoid poisoning-related medical encounters, poisoning involving cannabinoids and other psychoactive substances, and cannabinoid poisoning-related cardiac complications. Methods: Administrative billing data for emergency department visits and inpatient hospitalizations in acute care facilities with a discharge date from January 1, 2017 to December 31, 2019 were used to characterize cannabinoid poisoning events in Kentucky, identified by ICD-10-CM diagnosis code T40.7X. Results: There were 1,490 encounters of cannabinoid poisoning; patients were primarily non-Hispanic White males, ages 15-44, who had Medicaid and lived in a metropolitan area. Of those, 31.21% involved poisoning with a second psychoactive substance, primarily stimulants and/or opioids, and 17.72% experienced a cardiac complication. Cannabinoid-polydrug poisoning was associated with inpatient treatment (χ2=199.18, p < 0.001) and cardiac complications (χ2=4.58, p < 0.001). Discussion and Conclusions: These results are consistent with other state-level data. Patients who were diagnosed with cannabis-polydrug poisoning, compared to cannabis alone poisoning, had greater odds of hospital admission and cardiac complications, and longer length of hospital stays. Scientific Significance: The health risks of cannabinoid use must be more broadly recognized, while timely and accurate data need to be shared to guide policies on cannabis access. Future research on cannabinoid poisoning should consider the involvement of other psychoactive drugs.

Admissions to substance use treatment facilities for cannabis use disorder, 2000-2017: Does legalization matter?

BACKGROUND AND OBJECTIVES

A growing number of US states have legalized marijuana use in the past decade. We examined if marijuana legalization is associated with increased marijuana-related admissions to substance use treatment facilities between 2000 and 2017.

METHODS

Data from the Treatment Episode Data Set-Admissions were used to examine the relationship between marijuana-related admissions among adults aged ≥18 by year and legalization status (i.e., fully legalized, medical use only [partially legalized], and illegal) (N = 35,457,854). Using interaction analyses, we further examined whether certain patient characteristics were associated with residence in states that legalized marijuana use as compared to those in which marijuana remained illegal.

RESULTS

Overall, the proportion of marijuana-related admissions in states with legalization decreased by 2.3% from 31.7% in 2000-2005 to 29.4% in 2012-2017 (odds ratio [OR], 0.90; 95% confidence intervals [CI], 0.89-0.90) with little difference from states where marijuana use remained illegal, in which marijuana use as any reason for admissions decreased by 0.3% from 39.8% in 2000-2005 to 39.5% in 2012-2017 (OR, 0.99; 95% CI, 0.98-0.99). We did not find any striking patient characteristics (e.g., referral by the police) associated with admissions in states that legalized compared to those that had not.

DISCUSSION AND CONCLUSIONS

While earlier studies suggested that marijuana legalization is associated with increased levels of use, emergency department visits, and traffic fatalities, our findings suggest that marijuana legalization did not increase marijuana-related treatment use in the United States.

SCIENTIFIC SIGNIFICANCE

This is the first study to examine the association of marijuana legalization with marijuana-related treatment use.

Management site and level of health care for cannabis- and synthetic cannabinoid-related poison control center cases involving older adults, 2016-2019

Increasing numbers of older adults use cannabis and cannabis-derived products that can have adverse effects. This study examined management site and level of healthcare services for older adult poison control center cases involving cannabis products. Using the American Association of Poison Control Centers' (PCC) National Poison Data System, 2016-2019, we extracted the 3109 cases aged 50+ for which cannabis was the only or primary substance. Multinomial logistic regression models were fit to examine associations between specific cannabis forms and management/care site (on site [mostly at home], at a healthcare facility [HCF], or no follow-up due to referral refusal or leaving against medical advice) and level of healthcare services for cases managed at a HCF. The results show that between 2016 and 2019, PCC cannabis cases involving older adults increased twofold, largely due to cases of cannabidiol, edibles, and concentrated extracts. Plant form and synthetic cannabinoid cases declined substantially. Compared to plant forms, synthetic cannabinoid cases had 4.22 (95% CI = 2.59-6.89) greater odds of being managed at, rather than outside, a HCF and 2.17 (1.42-3.31) greater odds of critical care unit admission. Although e-cigarette cases, compared to plant form cases, had lower odds of being managed at a HCF, HCF-managed e-cigarette cases had 3.43 greater odds (95% CI = 1.08-10.88) of critical care unit admission. Synthetic cannabinoid cases also had 1.86 (95% CI = 1.03-3.35) greater odds of no follow-up, and the presence of a secondary substance was also a significant factor. Stricter regulations for listing chemical ingredients and providing safety guidelines are needed for cannabis-derived products.

Impact of cannabis legalization on healthcare utilization for psychosis and schizophrenia in Colorado

BACKGROUND

Emergency department (ED) visits involving psychosis and schizophrenia have increased at a rate exceeding population growth in the United States over the past decade. Research shows a strong dose-response relationship between chronic use of high-potency cannabis and odds of developing symptoms of psychosis. The aim of this study was to evaluate the impact of cannabis legalization on psychosis and schizophrenia-related ED visits in Colorado.

METHODS

Using administrative data from Colorado Hospital Association (CHA) on county-level quarterly ED visits between January 1, 2013, and December 31, 2018, we applied a difference-in-difference analysis to examine how new exposure to recreational cannabis dispensaries after 2014 differentially influenced the rate of ED visits for psychosis and schizophrenia, comparing counties with no prior medical cannabis dispensary exposure to counties with low or high medical dispensary exposure.

RESULTS

As recreational dispensaries per 10,000 residents increased, there was no significant association with the rate of schizophrenia ED visits per capita (incidence rate ratio or IRR: 0.95, 95% CI [0.69, 1.30]) while the rate of psychosis visits increased 24% (IRR: 1.24, 95% CI [1.02, 1.49]). Counties with no previous medical dispensaries experienced larger increases in schizophrenia ED visits than counties already exposed to a low level of medical dispensaries, but this effect was not significant. Counties with low baseline medical exposure had lower increases in rates of psychosis visits than counties with high baseline medical exposure (IRR 0.83, 95% CI [0.69, 0.99]).

CONCLUSIONS

There was a positive association between the number of cannabis dispensaries and rates of psychosis ED visits across all counties in Colorado. Although it is unclear whether it is access to products, or the types of products that may be driving this association, our findings suggest there is a potential impact on the mental health of the local population that is observed after cannabis legalization.

Varied Presentations of Pediatric Patients With Positive Cannabinoid Tests

Background: Cannabis (marijuana) is one of the most abused drugs worldwide. The increasing availability of cannabis has been associated with increased emergency department (ED) visits. There is a wide range of presentations documented in the recent literature, and the full scope of symptoms in young children is not fully known.

Objective: The primary objectives were to gather information regarding the characteristics in the presentation of the children with positive cannabinoid urine drug screen (UDS) results in the ED and to determine if there are certain common presentations with cannabinoid ingestion or inhalation.

Design/methods: This study was a descriptive retrospective chart review from March 2013 to June 2020 of pediatric patients <18 years old with positive UDS for cannabinoids. Data collected included age, gender, chief complaint, history, review of systems, vital signs, physical exam findings, laboratory studies, imaging findings, and disposition. Four hundred and twenty-two charts were included in the study. Analysis was done using Stata 13 (College Station, TX).

Results: The data showed that there was a significant increase in the number of pediatric patients with a positive UDS after cannabis legalization. Using cases from November 2013 to November 2019 showed 71% of cases presented after legalization on November 8, 2016 (Z=7.72, p<.01). The majority of cases were patients between the ages of 15 and 17 (78%). 43% (n=182) of patients presented with chief complaints of suicidal ideation. The other most common chief complaints were vomiting (8%, n=33), nausea (5%, n=22), trauma (5%, n=21), and altered mental status (AMS) (5%, n=20). The most common vital sign abnormalities included tachycardia (27%, n=115) and hypertension (18%, n=74). Forty-two percent of patients had tests ordered during their visit with 7% undergoing head computerized tomography. On the UDS, 28% of patients were positive for at least one other drug with amphetamine being the most common (13%, n=55).

Conclusion: Our data showed a significant increase in the number of cases since the legalization of cannabis in 2016, supporting the need for ED physicians to become more familiar with cannabis intoxication and its complications. The presentations of these patients can vary greatly. Common presentations include suicidal ideation, nausea/vomiting, AMS, and trauma with vital sign abnormalities including tachycardia and hypertension. Physicians should continue to consider cannabis use when evaluating these pediatric complaints. It may decrease the number of tests ordered in this patient population.

Predictors of no, low and frequent emergency department use for any medical reason among patients with cannabis-related disorders attending Quebec (Canada) addiction treatment centres

INTRODUCTION

Patients with substance-related disorders and mental disorders (MD) contribute substantially to emergency department (ED) overcrowding. Few studies have identified predictors of ED use integrating service use correlates, particularly among patients with cannabis-related disorders (CRD). This study compared predictors of low (1-2 visits/year) or frequent (3+ visits/year) ED use with no ED use for a cohort of 9836 patients with CRD registered at Quebec (Canada) addiction treatment centres in 2012-2013.

METHODS

This longitudinal study used multinomial logistic regression to evaluate clinical, sociodemographic and service use variables from various databases as predictors of the frequency of ED use for any medical reason in 2015-2016 among patients with CRD.

RESULTS

Compared to non-ED users with CRD, frequent ED users included more women, rural residents, patients with serious MD and chronic CRD, dropouts from programs in addiction treatment centres and with less continuity of physician care. Compared with non-users, low ED users had more common MD and there more workers than students.

DISCUSSION AND CONCLUSIONS

Multimorbidity, including MD, chronic physical illnesses and other substance-related disorders than CRD, predicted more ED use and explained frequent use of outpatient services and prior specialised acute care, as did being 12-29 years, after controlling for all other covariates. Better continuity of physician care and reinforcement of programs like assertive community or integrated treatment, and chronic primary care models may protect against frequent ED use. Strategies like screening, brief intervention and treatment referral, including motivational therapy for preventing treatment dropout may also be expanded to decrease ED use.

Comparison of hospital claims and poison center data to evaluate health impact of opioids, cannabis and synthetic cannabinoids

INTRODUCTION

Over the past 10 years, opioids and cannabis have garnered significant attention due to misuse and legalization trends. Different datasets and surveillance mechanisms can lead to different conclusions the due to a variety of factors. The primary objective of this study was to compare and describe trends of opioid, cannabis, and synthetic cannabinoid-related healthcare encounters and poison center (PC) cases in Colorado, a state that has legalized cannabis.

METHODS

This was a retrospective study comparing hospital claims data (Colorado Hospital Association (CHA)) and poison center cases to describe opioid, cannabis and synthetic cannabinoid-related healthcare encounters and exposures in Colorado from 2013 to 2017 using related genetic codes and International Statistical Classification of Disease codes.

RESULTS

Both datasets observed increases in cannabis related encounters and exposures after recreational cannabis legalization in 2014. CHA reported an increase for cannabis-related ER visits from 14,109 in 2013 to 18,118 in 2017 while PC noted a 74.4% increase in cannabis-related cases (125 to 218). CHA inpatient visits associated with cannabis also increased (8311 in 2013 to 14,659 in 2017). On the other hand, Opioid-related exposures to the PC fell (1092 in 2013 to 971 in 2017) while both Opioid-related ER visits (8580 in 2013 to 12,928 in 2017) and inpatient visits in CHA increased (9084 in 2013 to 13,205).

CONCLUSIONS

This study demonstrates the differences in surveillance methodology for concurrent drug abuse epidemics using hospital claims and PC data. Both systems provide incomplete reports, but in combination can provide a more complete picture.

Associations of Healthcare Service Utilization With Cannabis Use Status, Use Reasons, and Use Characteristics Among Those Age 50 and Older

Cannabis use has increased steadily among older adults, and they are a significant proportion of medical cannabis users. Using 2015-2019 National Survey on Drug Use and Health data (n = 44,007 age 50+), we examined whether the numbers of emergency department (ED) visits and nights hospitalized are associated with cannabis use status, use reason (nonmedical-only, medical-only, and medical and nonmedical), and use characteristics. Past-year users had higher rates of any ED visit (30.0%) and hospitalization (14.7%) than prior-to-past-year users and never users. However, negative binomial regression models showed that past-year users did not differ from never users on numbers of ED visits and nights hospitalized, although they had more ED visits than prior-to-past-year users (IRR = 1.21, 95% CI = 1.10-1.34). Medical-only users had more ED visits (IRR = 1.38, 95% CI = 1.02-1.88) than nonmedical-only users. Cannabis use and use characteristics were not associated with nights hospitalized. The study findings provide insights into older cannabis users' healthcare utilization.

Cannabis and Mental Health: Adverse Outcomes and Self-Reported Impact of Cannabis Use by Mental Health Status

Background: Cannabis can induce negative outcomes among consumers with mental health conditions. This study examined medical help-seeking behavior, patterns of adverse effects, and perceived impacts of cannabis among consumers with and without mental health conditions. Methods: Data came from the International Cannabis Policy Study, via online surveys conducted in 2018. Respondents included 6,413 past 12-month cannabis consumers aged 16-65, recruited from commercial panels in Canada and the US. Regression models examined differences in adverse health effects and perceived impact of cannabis among those with and without self-reported past 12-month experience of anxiety, depression, PTSD, bipolar disorder, psychosis. Results: Overall, 7% of past 12-month consumers reported seeking medical help for adverse effects of cannabis, including panic, dizziness, nausea. Help-seeking was greater for those with psychosis (13.8%: AOR = 1.78; 1.11-2.87), depression (8.9%: AOR = 1.57; 1.28-1.93), and bipolar disorder (10.1%: AOR = 1.53; 1.44-2.74). Additionally, 54.1% reported using cannabis to manage symptoms of mental health, with higher rates among those with bipolar (90.8%) and PTSD (90.7%). Consumers reporting >1 condition were more likely to perceive positive impacts on friendships, physical/mental health, family life, work, studies, quality of life (all p < .001). Consumers with psychosis were most likely to perceive negative effects across categories. Conclusion: For conditions with substantial evidence suggesting cannabis is harmful, greater help-seeking behaviors and self-perceived negative effects were observed. Consumers with mental health conditions generally perceive cannabis to have a positive impact on their lives. The relationship between cannabis and mental health is disorder specific and may include a combination of perceived benefits and harms.

How High? Trends in Cannabis Use Prior to First Admission to Inpatient Psychiatry in Ontario, Canada, between 2007 and 2017

OBJECTIVES

To examine the trends in cannabis use within 30 days of first admission to inpatient psychiatry in Ontario, Canada, between 2007 and 2017, and the characteristics of persons reporting cannabis use.

METHODS

A retrospective cross-sectional analysis was conducted for first-time admissions to nonforensic inpatient psychiatric beds in Ontario, Canada, between January 1, 2007, and December 31, 2017, using data from the Ontario Mental Health Reporting System (N = 81,809).

RESULTS

Across all years, 20.1% of patients reported cannabis use within 30 days of first admission. Use increased from 16.7% in 2007 to 25.9% in 2017, and the proportion with cannabis use disorders increased from 3.8% to 6.0%. In 2017, 47.9% of patients aged 18 to 24 and 39.2% aged 25 to 34 used cannabis, representing absolute increases of 8.3% and 10.7%, respectively. Increases in cannabis use were found across almost all diagnostic groups, with the largest increases among patients with personality disorders (15% increase), schizophrenia or other psychotic disorders (14% increase), and substance use disorders (14% increase). A number of demographic and clinical factors were significantly associated with cannabis use, including interactions between schizophrenia and gender (area under the curve = 0.88).

CONCLUSIONS

As medical cannabis policies in Canada have evolved, cannabis use reported prior to first admission to inpatient psychiatry has increased. The findings of this study establish a baseline for evaluating the impact of changes in cannabis-related policies in Ontario on cannabis use prior to admission to inpatient psychiatry.

Review of cannabis reimbursement by workers' compensation insurance in the U.S. and Canada

Changing public attitudes about cannabis consumption have currently led 36 U.S. states and the District of Columbia to approve laws that make cannabis available to consumers with qualifying medical conditions. This article reviews the 36 states and the District of Columbia with medical cannabis access laws to determine if the state or the District also allows reimbursement of the costs of cannabis for a work-related health condition under that state's or District's workers' compensation insurance (WCI) laws and administrative regulations. The legal basis for a state allowing or not allowing WCI reimbursement is described. The review found that only six of the 36 states expressly allow cannabis WCI reimbursement, six expressly prohibit it, 14 states do not require reimbursement, and 10 states, and the District of Columbia, are silent on the issue. The article describes the role of the insurer, treating physician, and worker in obtaining WCI reimbursement in the six states that expressly allow cannabis WCI reimbursement. Comparisons are made to how selected Canadian provinces and territories administer cannabis reimbursement under Canada's new national cannabis legalization law. The article discusses the future role of cannabis legalization in the United States and the evolving role of cannabis from an international perspective.

Sociodemographic Characteristics Associated With and Prevalence and Frequency of Cannabis Use Among Adults in the US

IMPORTANCE

Cannabis use has increased, but there are few studies on frequent and daily cannabis use among US adults. Individuals who engage in higher frequency use may suffer more health consequences.

OBJECTIVE

To examine frequency of cannabis use and associated factors among US adults.

DESIGN, SETTING, AND PARTICIPANTS

This survey study included data from 21 US states and 2 US territories reported in the Behavioral Risk Factor Surveillance System surveys from 2016 to 2019. Cross-sectional data on US adults ages 18 years and older were used to estimate demographic, socioeconomic, and behavioral risk factors for cannabis use, taking into account the survey strata and sampling weights for the 4 years of combined data. Using a multivariable ordinal logistic analysis, the association of demographic, socioeconomic status, and behavioral risk factors with past month cannabis frequency were examined.

EXPOSURES

Sociodemographic characteristic, ie, age, gender, race and ethnicity, educational attainment, employment status, and annual household income.

MAIN OUTCOMES AND MEASURES

Ordinal categorization of number of days of cannabis use in the past 30 days in terms of nonuse, infrequent use (1-5 days), frequent use (6-29 days), and daily use.

RESULTS

Among the 387 179 respondents, 58 009 (27.9%) were ages 18 to 34 years, 186 923 (50.3%) were ages 35 to 64 years, and 142 225 (21.8%) were age 65 years or older (mean [SD] age, 48.3 [0.1] years). The sample included 28 345 (9.8%) Black, 36 697 (22.6%) Hispanic, and 292 210 (57.3%) White respondents. Smoking was the most common form of cannabis use. The frequency of cannabis use varied significantly by age, gender, race, marital status, education, and employment. Higher frequency cannabis use was associated with younger age (ages 18-34 years: adjusted odds ratio [aOR],4.12; 95% CI, 3.63-4.68; ages 35-64 years: aOR,2.22; 95% CI, 1.98-2.49), Black (aOR, 1.46; 95% CI, 1.33-1.71) and Native American (aOR, 1.25; 95% CI, 1.04-1.52) race, and less educational attainment (high school or less: aOR,1.09; 95% CI, 1.02-1.17; some college: aOR,1.27; 95% CI, 1.19-1.35). Being married (aOR, 0.54; 95% CI, 0.51-0.58) or identifying as Asian (aOR, 0.60; 95% CI, 0.51-0.71) or Hispanic (aOR, 0.71; 95% CI, 0.65-0.77) was associated with lower-frequency cannabis use after accounting for other baseline factors.

CONCLUSIONS AND RELEVANCE

This nationally based study found that higher-frequency cannabis use is more common among young and racial minority populations, as well as respondents with low socioeconomic status. Given the known and emerging negative health effects of cannabis use, more attention may need to be paid to high-frequency use among underserved populations in the form of screening, risk stratification, and treatment.

Clearing the air: A study of cannabis-related presentations to urban Alberta emergency departments following legalization

OBJECTIVES

Non-medical cannabis recently became legal for adults in Canada. Legalization provides opportunity to investigate the public health effects of national cannabis legalization on presentations to emergency departments (EDs). Our study aimed to explore association between cannabis-related ED presentations, poison control and telemedicine calls, and cannabis legalization.

METHODS

Data were collected from the National Ambulatory Care Reporting System from October 1, 2013, to July 31, 2019, for 14 urban Alberta EDs, from Alberta poison control, and from HealthLink, a public telehealth service covering all of Alberta. Visitation data were obtained to compare pre- and post-legalization periods. An interrupted time-series analysis accounting for existing trends was completed, in addition to the incidence rate ratio (IRR) and relative risk calculation (to evaluate changes in co-diagnoses).

RESULTS

Although only 3 of every 1,000 ED visits within the time period were attributed to cannabis, the number of cannabis-related ED presentations increased post-legalization by 3.1 (range -11.5 to 12.6) visits per ED per month (IRR 1.45, 95% confidence interval [CI]; 1.39, 1.51; absolute level change: 43.5 visits per month, 95% CI; 26.5, 60.4). Cannabis-related calls to poison control also increased (IRR 1.87, 95% CI; 1.55, 2.37; absolute level change: 4.0 calls per month, 95% CI; 0.1, 7.9). Lastly, we observed increases in cannabis-related hyperemesis, unintentional ingestion, and individuals leaving the ED pre-treatment. We also observed a decrease in co-ingestant use.

CONCLUSION

Overall, Canadian cannabis legalization was associated with small increases in urban Alberta cannabis-related ED visits and calls to a poison control centre.

Changes in Rates of Hospitalizations due to Cannabis Harms in Ontario, Canada Before the Legalization of Nonmedical Cannabis: Retrospective Population-level Study Between 2003 and 2017

OBJECTIVES

To assess the burden of hospitalizations due to cannabis harms in Ontario, Canada before Canada's legalization of nonmedical cannabis.

METHODS

We conducted a retrospective population-level study that included all individuals living in Ontario between 2003 and 2017. We described patterns of hospitalizations due to cannabis harms in men and women by demographics, socioeconomic factors, and mental health comorbidities. We calculated annual crude rates of hospitalizations due to cannabis harms and assessed time trends using Poisson regression models.

RESULTS

There were 39,092 hospitalizations due to cannabis harms among 32,811 unique individuals. Annual hospitalizations due to a cannabis harm increased by 280% between 2003 and 2017 (1712 vs 4730), with increases noted for all age groups and sexes. Rates of hospitalizations due to cannabis harms were greater in young adults, low-income individuals, and those with mental health comorbidities. Overall, the rate of hospitalizations due to cannabis harms increased on average by 7.8% per year (95% CI 7.5-8.0). Women aged 15 to 24 experienced the largest average annual increase (12.2% per year, 95% CI 11.5 to 12.8).

CONCLUSIONS

There are distinct patterns of hospitalizations due to cannabis harms in different priority populations. Young women aged 15 to 24 are a key demographic that is disproportionately burdened with a rapid increase in hospitalizations due to cannabis harms. Jurisdictions considering new approaches to cannabis control policy and addiction services should consider the rising burden of harms faced by youth and young adults when planning interventions.

Cannabis Retail Staff ("Budtenders") Attitudes Towards Cannabis Effects on Health and Experiences Interacting with Consumers - Washington State, USA

Cannabis legalization in Washington State has increased the availability, consumption, and potency of cannabis products for adults. Public health education promoting safe use for adult consumers has lagged behind these trends. This study assesses the potential of cannabis retail workers (budtenders) to engage in responsible use education with adult consumers at point of sale. Focus groups explored how budtenders perceive their professional role, including educating consumers about cannabis over intoxication, storage, and risks of use before driving and during pregnancy. Transcripts were analyzed to develop a coding scheme, which was then applied with an iterative review by the research team. Budtenders identified three main professional roles: creating a good experience for customers; being compliant with the state law and regulations, and educating customers on products. Budtenders did not believe their job involved discussing use during pregnancy or while driving or safe storage. They prioritized customers' autonomy over education on these topics, and they did not necessarily consider these behaviors to be harmful. Budtenders are committed to keeping minors outside stores and educating consumers on how to avoid over intoxication and exposure to cannabis contaminants. Future research could build on this to develop point-of-sale education to reduce cannabis use risks.

Interrupted time series analysis of cannabis coding in Colorado during the ICD-10-CM transition

The International Classification of Diseases, 10^th Revision, Clinical Modification (ICD-10-CM), implemented in 2015, has more codes than ICD-9-CM for events involving cannabis. We examined cannabis indicator trends across the transition from ICD-9-CM to ICD-10-CM in Colorado, where state law regulates adult cannabis use. Using 2011 to 2018 data from hospital and emergency department (ED) discharges, we calculated monthly rates per 1000 discharges for two indicators: (1) cannabis use disorders and (2) poisoning and adverse effects of psychodysleptics. Immediate, point-of-transition (level) and gradual, post-transition (slope) changes across the ICD-9-CM to ICD-10-CM transition were tested using interrupted time series models adjusted for legalisation, seasonality and autocorrelation. We observed a level increase and slope increase in the rate of ED discharges with cannabis use disorders. Hospital discharges with cannabis use disorders had a negative slope change after the transition and no level change. ED discharges with poisoning and adverse effects of psychodysleptics showed an increase in slope after the transition. No effects of the transition were observed on hospital discharges with poisoning and adverse effects of psychodysleptics. Shifts in the level and slope of cannabis indicator rates after implementation of the new coding scheme suggest the use of caution when interpreting trends spanning the ICD-9-CM to ICD-10-CM transition.

When Cannabis Use Goes Wrong: Mental Health Side Effects of Cannabis Use That Present to Emergency Services

Cannabis use is a modifiable risk factor for the development and exacerbation of mental illness. The strongest evidence of risk is for the development of a psychotic disorder, associated with early and consistent use in youth and young adults. Cannabis-related mental health adverse events precipitating Emergency Department (ED) or Emergency Medical Services presentations can include anxiety, suicidal thoughts, psychotic or attenuated psychotic symptoms, and can account for 25-30% of cannabis-related ED visits. Up to 50% of patients with cannabis-related psychotic symptoms presenting to the ED requiring hospitalization will go on to develop schizophrenia. With the legalization of cannabis in various jurisdiction and the subsequent emerging focus of research in this area, our understanding of who (e.g., age groups and risk factors) are presenting with cannabis-related adverse mental health events in an emergency situation is starting to become clearer. However, for years we have heard in popular culture that cannabis use is less harmful or no more harmful than alcohol use; however, this does not appear to be the case for everyone. It is evident that these ED presentations should be considered another aspect of potentially harmful outcomes that need to be included in knowledge mobilization. In the absence of a clear understanding of the risk factors for mental health adverse events with cannabis use it can be instructive to examine what characteristics are seen with new presentations of mental illness both in emergency departments (ED) and early intervention services for mental illness. In this narrative review, we will discuss what is currently known about cannabis-related mental illness presentations to the ED, discussing risk variables and outcomes both prior to and after legalization, including our experiences following cannabis legalization in Canada. We will also discuss what is known about cannabis-related ED adverse events based on gender or biological sex. We also touch on the differences in magnitude between the impact of alcohol and cannabis on emergency mental health services to fairly present the differences in service demand with the understanding that these two recreational substances may impact different populations of individuals at risk for adverse events.

Cannabis and work: Need for more research

Cannabis sativa is one of the oldest and most widely used plants in the world with a variety of industrial, medical, and nonmedical applications. Despite its long history, cannabis-derived products remain a source of controversy across the fields of medicine, law, and occupational safety and health. More favorable public attitudes about cannabis in the US have resulted in greater access to cannabis through legalization by states, leading to more consumption by workers. As more states adopt cannabis access laws, and as more workers choose to consume cannabis products, the implications for existing workplace policies, programs, and practices become more salient. Past workplace practices were grounded in a time when cannabis consumption was always viewed as problematic, considered a moral failing, and was universally illegal. Shifting cultural views and the changing legal status of cannabis indicate a need for research into the implications and challenges relating to cannabis and work. This commentary suggests research needs in the following areas: (a) data about industries and occupations where cannabis consumption among workers is most prevalent; (b) adverse health consequences of cannabis consumption among workers; (c) workplace supported recovery programs; (d) hazards to workers in the emerging cannabis industry; (e) relationship between cannabis consumption and occupational injuries; (f) ways to assess performance deficits and impairment from cannabis consumption; (g) consumption of synthetic cannabinoids to evade detection by drug testing; (h) cannabis consumption and its effect on occupational driving; and (i) ways to craft workplace policies and practices that take into consideration conflicting state and federal laws pertaining to cannabis.

Psychiatric emergency care during Coronavirus 2019 (COVID 19) pandemic lockdown: results from a Department of Mental Health and Addiction of northern Italy

BACKGROUND

The current COVID-19 pandemic and the consequent containment measures are leading to increasing mental health issues both in psychiatric patients and general population.

OBJECTIVE

We aimed to compare the number and characteristics of emergency psychiatric consultations during the phase 1 of lockdown with respect to the same period in 2019 in a Department of Mental Health and Addiction (DMHA) located in Lombardy region.

METHODS

We conducted a cross-sectional study including subjects consecutively admitted to two psychiatric emergency rooms of DMHA in Monza, Lombardy, Italy. Sociodemographic data, clinical characteristics, referred symptoms, diagnosis and information on patients' illness course following the emergency consultations were collected. No subjects were excluded for the purposes of the study.

RESULTS

Between February 21st and May 3rd 2020, there was a marked reduction in the number of psychiatric emergency consultations, if compared to the same period of 2019. Subjects who were living in psychiatric residential treatment facilities, had cannabis addiction and a diagnosis of obsessive-compulsive disorder were significantly more likely to present to emergency psychiatric consultations during lockdown.

CONCLUSIONS

COVID-19 epidemic may have a negative impact on more vulnerable individuals. Strategies to enhance relapse prevention and the use of alternative approaches as e-health technologies should be promoted.

Impacts de la légalisation du cannabis récréatif sur la santé mentale : une recension des écrits

Objectif Cet article présente une recension des écrits sur l’impact de la légalisation du cannabis récréatif sur la santé mentale et s’inscrit dans le contexte des politiques canadiennes récemment adoptées à cet égard.

Méthode Cette recension a été effectuée dans la base de données PubMed en utilisant la combinaison de termes associés au cannabis, à la légalisation et à la santé mentale. Deux évaluateurs indépendants ont ensuite examiné 272 titres et résumés, puis ont conservé 11 articles.

Résultats À la suite de la révision des articles, nous constatons que la plupart des études ciblant la consommation de cannabis décrivent une prévalence croissante d’utilisateurs. Il est à noter qu’aucune étude n’a démontré une diminution de la consommation du cannabis après la légalisation. Parmi les 11 articles retenus, trois évaluent la perception des risques associés au cannabis (avant et après la légalisation). Deux d’entre eux montrent une diminution des risques perçus après la légalisation, alors que le troisième décrit l’inverse. Quelques études ont également analysé l’impact de la légalisation du cannabis sur le nombre de visites à l’urgence générale et elles montrent toutes une augmentation du nombre de visites associées au cannabis. Cela dit, ces résultats sont simplement observationnels et sont à mettre en perspective avec les tendances qui prévalaient déjà avant la légalisation du cannabis.

Conclusion Cette recension des écrits montre qu’il existe un nombre limité d’études concernant l’impact de la légalisation du cannabis récréatif sur les troubles en santé mentale. Il serait donc intéressant de poursuivre les recherches sur ce sujet.

Changes in Healthcare Encounter Rates Possibly Related to Cannabis or Alcohol following Legalization of Recreational Marijuana in a Safety-Net Hospital: An Interrupted Time Series Analysis

OBJECTIVES

Liberalization of marijuana laws in Colorado contributed to increases in cannabis-related adverse events over time. We examined characteristics of patients with healthcare encounters possibly related to cannabis and assessed the temporal association between legalization of recreational marijuana and healthcare encounters possibly attributed to cannabis.

METHODS

Annual encounter rates possibly related to cannabis and alcohol were compared using negative binomial regression. Two-time intervals, pre/post-recreational marijuana legalization (January 2009 to December 2013 and January 2014 to December 2015, respectively) were used to examine changes in monthly rates of emergency encounters and hospitalizations possibly related to cannabis. Level and trend changes on encounter rates by legalization period were assessed using interrupted time series analyses. Encounters possibly related to alcohol were used as a comparator group.

RESULTS

Most encounters identified during the study period had alcohol-related International Classification of Diseases Diagnosis and Procedural Codes (ICD-9/10-CM) codes (94.8% vs 5.2% for cannabis). Patients with encounters possibly related to cannabis were younger, more likely to be hospitalized and more likely to be admitted to the psychiatric unit than patients with encounters possibly related to alcohol. Initial and sustained effects of encounter rates possibly related to cannabis demonstrated an increased trend in slope before and after recreational marijuana legalization. The slope became more abrupt following legalization with a significant increase in trend during the post-legalization period (β = 2.7, standard error = 0.3, ρ < 0.0001). No significant change was noted for encounters possibly related to alcohol.

CONCLUSIONS

Additional research should identify patients at highest risk of an adverse health event related to cannabis and quantify costs associated with cannabis-related healthcare delivery.

Cannabis Dependence or Abuse in Kidney Transplantation: Implications for Posttransplant Outcomes

BACKGROUND

Cannabis is categorized as an illicit drug in most US states, but legalization for medical indications is increasing. Policies and guidance on cannabis use in transplant patients remain controversial.

METHODS

We examined a database linking national kidney transplant records (n = 52 689) with Medicare claims to identify diagnoses of cannabis dependence or abuse (CDOA) and associations [adjusted hazard ratio (aHR) with 95% upper and lower confidence limits (CLs)] with graft, patient, and other clinical outcomes.

RESULTS

CDOA was diagnosed in only 0.5% (n = 254) and 0.3% (n = 163) of kidney transplant recipients in the years before and after transplant, respectively. Patients with pretransplant CDOA were more likely to be 19 to 30 years of age and of black race, and less likely to be obese, college-educated, and employed. After multivariate and propensity adjustment, CDOA in the year before transplant was not associated with death or graft failure in the year after transplant, but was associated with posttransplant psychosocial problems such as alcohol abuse, other drug abuse, noncompliance, schizophrenia, and depression. Furthermore, CDOA in the first year posttransplant was associated with an approximately 2-fold increased risk of death-censored graft failure (aHR, 2.29; 95% CL, 1.59-3.32), all-cause graft loss (aHR, 2.09; 95% CL, 1.50-2.91), and death (aHR, 1.79; 95% CL, 1.06-3.04) in the subsequent 2 years. Posttransplant CDOA was also associated with cardiovascular, pulmonary, and psychosocial problems, and with events such as accidents and fractures.

CONCLUSIONS

Although associations likely, in part, reflect associated conditions or behaviors, clinical diagnosis of CDOA in the year after transplant appears to have prognostic implications for allograft and patient outcomes. Recipients with posttransplant CDOA warrant focused monitoring and support.

The Role of the Cannabinoid System in Pain Control: Basic and Clinical Implications

PURPOSE OF REVIEW

The purpose of this review is to provide a comprehensive update of the different known components of the endogenous cannabinoid system and the mechanisms of action, as it applies to analgesia.

RECENT FINDINGS

Following the discovery of the endogenous cannabinoid system in the early 1990s and the subsequent characterization of the cannabinoid receptor, there has been a renewed interest in cannabinoid research. Recent work has demonstrated its efficacy as a pharmacologic agent. There is limited evidence in the literature about the understanding of the endocannabinoid system and its role in the treatment and management of acute and chronic pain. Further work may elucidate additional roles for the endocannabinoid system within our nervous system and, moreover, additional subtypes of cannabinoid receptors have yet to be discovered. Cannabinoid compounds mediate their biological effects via binding and subsequent activation of cannabinoid receptors. These receptors are located throughout the body and make up the endocannabinoid system. These receptors are best understood and have been cloned, type 1 (CB₁) and type 2 (CB₂) [ (1, 2)] [ (1, 2)] [ (1, 2)] [ (1, 2)] [ (1, 2)] [ (1, 2)] [ (1, 2)] [ (1, 2)] [ (1, 2)] [ (1, 2)] [ (1, 2)] [ (1, 2)] [ (1, 2)] [ (1, 2)] [ (1, 2)] [ (1, 2)] [ (1, 2)] [ (1, 2)] [ (1, 2)] [ (1, 2)] [ (1, 2)] [ (1, 2)] [ (1, 2)]. The CB₂ receptor is located primarily in the immune system. CB₁ receptors are primarily located in the nervous system with the highest concentrations in the brain and lower concentrations in the spine and peripheral nervous tissues. Cannabinoids may be promising treatments for neuropathic pain with limited evidence, whereas, the evidence for other uses is insufficient.

The perils of recreational marijuana use: relationships with mental health among emergency department patients

INTRODUCTION

Marijuana is a commonly used drug in the United States. Many states have legalized the recreational use of marijuana. The effects of marijuana on mental health are unknown.

METHODS

In this prospective survey study, eligible participants included ED patients age 18 and older, who had ever used recreational marijuana. A survey instrument was developed, piloted, and revised. Data collected included reasons for marijuana use, marijuana's perceived effectiveness, and history of mental health conditions, including depression, anxiety, and suicidal thoughts.

RESULTS

Among 303 participants (86% response rate), the median age of first marijuana use was 16 ([IQR 14, 19], range 6-65). The most commonly cited reasons for marijuana use included recreational use (70%; n = 211), to treat anxiety (30%; n = 89), to treat pain (25%; n = 74), and to treat depression (17%; n = 51). Mental health issues were common in the study population. A majority of patients reported anxiety in the last 30 days (59%; n = 176), and a significant minority of patients reported serious depression in the last 30 days (46%; n = 137). Some patients reported suicidal thoughts in the last 30 days (9%; n = 29). Participants who used marijuana more frequently reported more days of anxiety (median 15.5, compared to 1; P = 0.001). Among participants with mental health conditions, most began using marijuana before the onset of the mental health conditions (77%, n = 167). Earlier age of starting to use marijuana was correlated with higher number of years of anxiety or tension in lifetime (r = -0.11, P = 0.05, n = 301). Perceived effects of marijuana use on mental health were variable. Most participants stated that marijuana improved their mental health (62%; n = 163), and some reported that marijuana did not improve their mental health (37%; n = 98).

CONCLUSIONS

Many ED patients have used marijuana, either currently or in the past. Mental health conditions are also common, including anxiety, depression, and suicidal thoughts. Most participants reported marijuana use starting at an age under 18. Marijuana use preceded the onset of mental health conditions in the majority of participants.

Assessing the public health impacts of legalizing recreational cannabis use: the US experience

The sale of cannabis for adult recreational use has been made legal in nine US states since 2012, and nationally in Uruguay in 2013 and Canada in 2018. We review US research on the effects of legalization on cannabis use among adults and adolescents and on cannabis-related harms; the impact of legalizing adult recreational use on cannabis price, availability, potency and use; and regulatory policies that may increase or limit adverse effects of legalization. The legalization of recreational cannabis use in the US has substantially reduced the price of cannabis, increased its potency, and made cannabis more available to adult users. It appears to have increased the frequency of cannabis use among adults, but not so far among youth. It has also increased emergency department attendances and hospitalizations for some cannabis-related harms. The relatively modest effects on cannabis use to date probably reflect restrictions on the number and locations of retail cannabis outlets and the constraints on commercialization under a continued federal prohibition of cannabis. Future evaluations of legalization should monitor: cannabis sales volumes, prices and content of tetrahydrocannabinol; prevalence and frequency of cannabis use among adolescents and adults in household and high school surveys; car crash fatalities and injuries involving drivers who are cannabis-impaired; emergency department presentations related to cannabis; the demand for treatment of cannabis use disorders; and the prevalence of regular cannabis use among vulnerable young people in mental health services, schools and the criminal justice system. Governments that propose to legalize and regulate cannabis use need to fund research to monitor the impacts of these policy changes on public health, and take advantage of this research to develop ways of regulating can-nabis use that minimize adverse effects on public health.

Patterns of Cannabis Use in Patients With Cyclic Vomiting Syndrome

BACKGROUND & AIMS

Some patients with cyclic vomiting syndrome (CVS) use cannabis to relieve stress and for its antiemetic properties. However, chronic cannabis use has been associated paradoxically with cannabinoid hyperemesis syndrome (CHS) and some patients with CVS are thought to have CHS. We sought to characterize patterns of cannabis use by patients with CVS and identify those who could be reclassified as having CHS.

METHODS

We performed a cross-sectional study of 140 patients with CVS (72% female; mean age, 37 ± 13 y) seen at a specialized clinic. Patients were screened for cannabis use with the cannabis use disorder identification test. Patients were classified as regular (use ≥4 times/wk) or occasional users (<4 times/wk).

RESULTS

Forty-one percent of patients were current cannabis users, with 21% reporting regular use. Regular users were more likely to be male and to report an anxiety diagnosis, and smoked cannabis with higher tetrahydrocannabinol content and for a longer duration. Most users reported that cannabis helped control CVS symptoms. Among all cannabis users, 50 of 57 (88%) reported that they had abstained for longer than 1 month, but only 1 user reported resolution of CVS episodes during the abstinence period. This patient subsequently resumed using cannabis but remains free of symptoms.

CONCLUSIONS

Cannabis is used commonly among patients with CVS-patients report relief of symptoms with use. We found 21% of patients with CVS to be regular users, but only 1 met the Rome IV criteria for CHS. Longitudinal studies are needed to determine the relationships among cannabis use, hyperemesis, and mood symptoms.

Cannabis use among U.S. adolescents in the era of marijuana legalization: a review of changing use patterns, comorbidity, and health correlates

Decriminalization, medicalization, and legalization of cannabis use by a majority of U.S. states over the past 25 years have dramatically shifted societal perceptions and use patterns among Americans. How marijuana policy changes have affected population-wide health of U.S. youth and what the downstream public health implications of marijuana legalization are topics of significant debate. Cannabis remains the most commonly used federally illicit psychoactive drug by U.S. adolescents and is the main drug for which U.S. youth present for substance use treatment. Converging evidence indicates that adolescent-onset cannabis exposure is associated with short- and possibly long-term impairments in cognition, worse academic/vocational outcomes, and increased prevalence of psychotic, mood, and addictive disorders. Odds of negative developmental outcomes are increased in youth with early-onset, persistent, high frequency, and high-potency Δ-9-THC cannabis use, suggesting dose-dependent relationships. Cannabis use disorders are treatable conditions with clear childhood antecedents that respond to targeted prevention and early intervention strategies. This review indicates that marijuana policy changes have had mixed effects on U.S. adolescent health including potential benefits from decriminalization and negative health outcomes evidenced by increases in cannabis-related motor vehicle accidents, emergency department visits, and hospitalizations. Federal and state legislatures should apply a public health framework and consider the possible downstream effects of marijuana policy change on paediatric health.

Cannabis Legalization and Acute Harm From High Potency Cannabis Products: A Narrative Review and Recommendations for Public Health

Legalization and commercial sale of non-medical cannabis has led to increasing diversity and potency of cannabis products. Some of the American states that were the first to legalize have seen rises in acute harms associated with cannabis use, e.g. Colorado has seen increases in emergency department visits for cannabis-related acute psychological distress and severe vomiting (hyperemesis), as well as a number of high-profile deaths related to ingestion of high doses of cannabis edibles. Over-ingestion of cannabis is related to multiple factors, including the sale of cannabis products with high levels of THC and consumers' confusion regarding labelling of cannabis products, which disproportionately impact new or inexperienced users. Based on our review of the literature, we propose three approaches to minimizing acute harms: early restriction of cannabis edibles and high-potency products; clear and consistent labelling that communicates dose/serving size and health risks; and implementation of robust data collection frameworks to monitor harms, broken down by cannabis product type (e.g. dose, potency, route of administration) and consumer characteristics (e.g. age, sex, gender, ethnicity). Ongoing data collection and monitoring of harms in jurisdictions that have existing legal cannabis laws will be vital to understanding the impact of cannabis legalization and maximizing public health benefits.

Emergency department visits during the 4/20 cannabis celebration

BACKGROUND

Annual '4/20' cannabis festivals occur around the world on April 20 and often feature synchronised consumption of cannabis at 4:20 pm. The relationship between these events and demand for emergency medical services has not been systematically studied.

METHODS

We conducted a population-based retrospective cohort study in Vancouver, Canada, using 10 consecutive years of data (2009-2018) from six regional hospitals. The number of emergency department (ED) visits between 4:20 pm and 11:59 pm on April 20 were compared with the number of visits during identical time intervals on control days 1 week earlier and 1 week later (ie, April 13 and April 27) using negative binomial regression.

RESULTS

A total of 3468 ED visits occurred on April 20 and 6524 ED visits occurred on control days. A non-significant increase in all-cause ED visits was observed on April 20 (adjusted relative risk: 1.06; 95% CI 1.00 to 1.12). April 20 was associated with a significant increase in ED visits among prespecified subgroups including a 5-fold increase in visits for substance misuse and a 10-fold increase in visits for intoxication. The hospital closest to the festival site experienced a clinically and statistically significant 17% (95% CI 5.1% to 29.6%) relative increase in ED visits on April 20 compared with control days.

INTERPRETATION

Substance use at annual '4/20' festivals may be associated with an increase in ED visits among key subgroups and at nearby hospitals. These findings may inform harm reduction initiatives and festival medical care service planning.

Psychiatric Emergency Department Visits After Regional Expansion of Community Health Centers

OBJECTIVE

Regional primary health care system capacity may affect the demand for psychiatric visits to the emergency department (ED). In the United States, community health centers (CHCs), which serve low-income regions regardless of individuals' ability to pay, expanded primary care services by over 70% in the past decade. No research, however, evaluates whether this expansion affects overall psychiatric ED visits. This hypothesis is tested in 143 U.S. counties that expanded CHC services.

METHODS

For the years 2006 through 2011, 18.84 million psychiatric outpatient ED visits were aggregated by county-year for the 143 U.S. counties with a participating CHC. The rate of psychiatric ED cases in a county-year is the dependent variable. Two independent variables were examined: total patients seen at CHCs and total patients receiving mental health services at CHCs. Fixed-effects regression methods controlled for county effects, year effects, and other health care and sociodemographic factors.

RESULTS

Psychiatric ED visits fell below expected levels in county-years where the volume of overall CHC patients rose (coefficient=-0.059; standard error=0.027, p=0.03). Findings indicate no relation between the volume of mental health patients seen at CHCs and psychiatric ED visits.

CONCLUSIONS

An increase in general primary health care to an underserved population, in the form of CHCs, corresponds with a decline in psychiatric ED visits. This result coheres with a recent Medicaid expansion experiment in which increased access to general primary care reduced the prevalence of undiagnosed and untreated depression. Findings, if replicated, may hold policy implications for regional health systems.

Why do patients come to the emergency department after using cannabis?

Background: Cannabis (MJ) policy liberalization in a majority of US states has impacted emergency department (ED) visits. It is important to understand why people come to the ED after using MJ because the drug is now available to experienced and naïve people across the country. The objectives of this study were to (1) improve upon administrative dataset methodology by performing additional chart review to describe ED visits related to cannabis, (2) understand why patients come to the ED after using cannabis, and (3) begin to inform our understanding of cannabis-attributable ED visits to start to educate patients and providers about cannabis' safety.Methods: We performed a retrospective chart review of ED visits identified by cannabis ICD-9 and 10-CM codes between 2012 and 2016. Visits were reviewed and determined if the visit was partially attributable to cannabis based upon a pre-specified definition, then categorized into clinical complaint categories. Descriptive statistics, Chi-Square, and T-tests were used to elucidate the data.Results: About one-fourth (25.74%) of visits with cannabis ICD-CM codes were found to be at least partially attributable to cannabis. These patients are more often young, Caucasian males when compared to the overall ED population (p < .0001). Patients with a cannabis-attributable visit were more often admitted to the hospital (p < .0001). The most common complaints in cannabis-attributable visits were gastrointestinal and psychiatric complaints, as well as intoxication. The number of cannabis-attributable visits rose with time (p=.012).Conclusions: Based on a pre-specified definition, with good inter-rater reliability, we found that 25% of visits with a cannabis ICD-CM code were partially attributable to cannabis. These findings represent areas to target in cannabis user education as public perceptions change across time.