National Estimates of Marijuana Use and Related Indicators - National Survey on Drug Use and Health, United States, 2002-2014

Disagreement and Uncertainty Among Experts About how to Respond to Marijuana Use in Patients on Long-term Opioids for Chronic Pain: Results of a Delphi Study

BACKGROUND

Marijuana use is common among patients on long-term opioid therapy (LTOT) for chronic pain, but there is a lack of evidence to guide clinicians' response.

OBJECTIVE

To generate expert consensus about responding to marijuana use among patients on LTOT.

DESIGN

Analysis from an online Delphi study.

SETTING/SUBJECTS

Clinician experts in pain and opioid management across the United States.

METHODS

Participants generated management strategies in response to marijuana use without distinction between medical and nonmedical use, then rated the importance of each management strategy from 1 (not at all important) to 9 (extremely important). A priori rules for consensus were established, and disagreement was explored using cases. Thematic analysis of free-text responses examined factors that influenced participants' decision-making.

RESULTS

Of 42 participants, 64% were internal medicine physicians. There was consensus that it is not important to taper opioids as an initial response to marijuana use. There was disagreement about the importance of tapering opioids if there is a pattern of repeated marijuana use without clinical suspicion for a cannabis use disorder (CUD) and consensus that tapering is of uncertain importance if there is suspicion for CUD. Three themes influenced experts' perceptions of the importance of tapering: 1) benefits and harms of marijuana for the individual patient, 2) a spectrum of belief about the overall riskiness of marijuana use, and 3) variable state laws or practice policies.

CONCLUSIONS

Experts disagree and are uncertain about the importance of opioid tapering for patients with marijuana use. Experts were influenced by patient factors, provider beliefs, and marijuana policy, highlighting the need for further research.

Household Rules regarding Cannabis Use and Tobacco Smoking in Denver Airbnb Venues

Cannabis legalization threatens to undermine clean indoor air norms. We investigated the prevalence and nature of tobacco and cannabis use rules in Airbnb venues in Denver, Colorado, where recreational cannabis was legalized in 2014. The study used publicly available Inside Airbnb data for all Denver listings (N = 4,511) collected on 06/29/2019. We analyzed reported tobacco smoking and cannabis use house rules. Tobacco smoking with or without conditions was allowed in 9.7% of venues. Of all venues, 23.7% included details about cannabis use. Of these, 75.9% allowed cannabis use without or with conditions. Of the venues that allowed cannabis use, 30.5% also allowed tobacco smoking. Of the venues that did not allow cannabis use, 0.4% allowed tobacco smoking. Additional multilevel regression models revealed that venues in higher income neighborhoods were less likely to allow cannabis and tobacco use. A substantial number of Airbnb listings in Denver, Colorado permit cannabis use and venues permitting cannabis use may be more likely to also permit tobacco smoking. Findings support the idea that cannabis legalization threatens clean indoor air norms. Airbnb should consider including cannabis use in house rules in jurisdictions that have legalized cannabis to help guests identify spaces with clean air.

Replicating the Dimensional Structure of Cannabis Problems: A Taxometric Analysis

This study employed taxometric procedures to replicate a previous report of the dimensional structure of problems related to cannabis consumption. Method: Over 4,000 cannabis users completed an assessment of psychological, social, occupational, and physical harms (the Marijuana Problems Scale). Three taxometric procedures (MAMBAC, MAXEIG, and L-Mode) compared the current data to simulations with a base rate of problematic cannabis use derived from representative, large-scale data estimates. Results: All three procedures confirmed the continuous, dimensional nature of these cannabis problems and suggested no underlying taxon or category. Conclusions: Psychopathological disorders, including some substance use problems, have fit categorical models suggesting that they differ in kind (rather than intensity) from the behavior of the rest of the population. Cannabis problems, however, appeared to lie along a continuum with other forms of use. Given heightened awareness for the necessity of replication and a changing legal landscape for cannabis, a second look at the dimensionality of these problems seemed warranted. New data with a larger sample and different indices of problematic use confirmed the dimensionality of cannabis problems. This replication can inform predictions about the etiology, prevention, and treatment of cannabis use disorder. Researchers should expect cannabis problems to range along a continuum without categorical distinctions. Dividing users into groups of problematic and non-problematic users likely sacrifices meaningful variance. Harm reduction strategies likely can benefit all users rather than a targeted taxon with troubles. In addition, interventions will likely progress by small, incremental steps rather than dramatic, categorical jumps in progress.

Cannabis use and sleep: Expectations, outcomes, and the role of age

STUDY OBJECTIVES

Determine relationship between cannabis use with 1) expectations of cannabis being a sleep aid, 2) subjective sleep outcomes, and 3) the influence of age on these relationships.

METHODS

In 152 moderate cannabis users with a wide age range (67% female, mean age = 31.45, SD = 12.96, age range = 21-70; mean days of cannabis use in prior two weeks = 5.54, SD = 5.25) we examined the influence of cannabis use history and behaviors on expectations of cannabis being a sleep aid and sleep outcomes via the Pittsburgh Sleep Quality Index (PSQI). Moderation analysis examined the role of age in the relationship between cannabis use and sleep outcomes.

RESULTS

Endorsing current cannabis use and more days of cannabis use were associated with increased expectations that cannabis use improves sleep (all β > 0.03, p < 0.04). Frequency of recent use and reported average THC or CBD concentration were largely not associated with sleep outcomes. However, endorsing current cannabis use was associated with worse subjective sleep quality (β = 1.34, p = 0.02) and increased frequency of consuming edibles was associated with worse subjective sleep efficiency (β = 0.03, p = 0.04), lower sleep duration (β = 0.03, p = 0.01), and higher global PSQI scores (worse overall sleep) (β = 0.10, p = 0.01). Additionally, age had a moderating influence on the relationship between increased self-reported concentration of CBD and both better sleep duration and sleep quality (both p < 0.03). While the main effects of cannabis use on sleep outcomes did not survive multiple comparisons correction test (all p adj > 0.34), the adjusted p values for the main effects of cannabis behaviors/history on expectations of cannabis as a sleep aid (p adj = 0.07-0.09) and the main effects of CBD concentration on sleep duration (p adj = 0.08), as well as the interaction terms of CBD and age for that model (p adj = 0.07), were trending.

CONCLUSION

Cannabis users have increased expectations of cannabis being a sleep aid, but few associations existed between cannabis use and sleep outcomes. The two exceptions were endorsing any cannabis use and frequency of edible use. Additionally, age may be an important moderator of the potential positive influence CBD concentration can have on sleep.

Examining Use and Dual Use of Tobacco Products and Marijuana among Minnesota Adults

BACKGROUND

An increasing number of states are legalizing the medicinal and/or recreational use of marijuana. Adult perceptions of harm have decreased and marijuana use has increased. This is in contrast to declining cigarette smoking. In this article we examine independent use and dual use of marijuana and tobacco products.

METHODS

Data are from the 2018 Minnesota Adult Tobacco Survey (N = 6055). Estimates were calibrated on sex, race, location, and education from the American Community Survey.

RESULTS

In 2018, 15.4% of adults smoked cigarettes in the past 30 days, 7.6% used marijuana and 6.0%, 3.0%, and 1.1% used e-cigarettes, cigars, and waterpipe, respectively. Use of marijuana and cigarettes was 3.3% and use of marijuana and e-cigarettes was 2.2%. Among past 30-day marijuana users, 89.7% smoked it as a joint, blunt, or in waterpipes, 22.1% vaped it in an e-cigarette or a vaping device. Across multinomial regression models, marijuana use and dual use with tobacco products was more likely among males, younger age groups, and African Americans.

CONCLUSIONS

As policies to expand the sale and use of marijuana are considered, states should anticipate the need to monitor trends and to plan surveys of sufficient sample size with specific questions on marijuana use. Understanding the proportion of the population that uses both marijuana and tobacco has implications for prevention and treatment of both substances.

Examining Associations Between Licensed and Unlicensed Outlet Density and Cannabis Outcomes From Preopening to Postopening of Recreational Cannabis Outlets

BACKGROUND AND OBJECTIVES

To expand on epidemiologic studies examining associations between the legalization of recreational cannabis and use among young adults, we examined the associations between licensed and unlicensed cannabis outlet density and cannabis outcomes.

METHODS

A total of 1097 young adults aged 21 and older living in Los Angeles County were surveyed before licensed recreational cannabis outlets opened (Time 1: July to December 2017) and after (Time 2: July 2018 to June 2019). Using a database of open licensed and unlicensed cannabis retailers to calculate individual-level cannabis outlet density measures, we examined associations between outlet density within a 4-mile radius of participants' residences with Time 2 outcomes of any past-month use, daily use, intentions to use, quantity used, consequences, and cannabis use disorder (CUD) symptoms.

RESULTS

After controlling for demographic factors and cannabis outcomes at a time point prior to their opening (Time 1), licensed cannabis outlets were associated with young adults' cannabis use, heavy use, and intentions, and unlicensed outlets were associated with young adults' heavy cannabis use and CUD symptoms.

CONCLUSION AND SCIENTIFIC SIGNIFICANCE

This study expands beyond studies of outlet prevalence to find that, after controlling for outcomes 1 year prior, licensed and unlicensed outlets were associated with young adults' cannabis outcomes. The current study is among the first to find associations between cannabis use outcomes and density of cannabis outlets among young adults using data from two time points: preopening and postopening of recreational cannabis retailers. Findings can inform policies around the density and placement of cannabis outlets. (Am J Addict 2020;00:00-00).

Topical Capsaicin for Treating Cannabinoid Hyperemesis Syndrome

Introduction

Cannabinoid hyperemesis syndrome (CHS), associated with chronic cannabis use, presents with cyclic abdominal pain, nausea, and vomiting. With increasing use of marijuana, the incidence of CHS is expected to increase. Most patients with CHS make frequent visits to the emergency room and are usually refractory to conventional treatment. We, therefore, present a case of CHS successfully treated with topical capsaicin application. Case Presentation. A 41-year-old female with a recent excess use of cannabis presented to the emergency department for evaluation of recurrent excruciating epigastric pain accompanied by severe nausea and vomiting. She had similar, milder symptoms a year ago and underwent endoscopic evaluation which was negative except for mild reflux esophagitis for which she was started on a proton pump inhibitor. On this presentation, basic laboratory workup, EKG, and CT scan of abdomen and pelvis were unremarkable. A detailed abdominal exam was only positive for mild epigastric tenderness. She was instructed to continue pantoprazole and pain medication and outpatient repeat esophagogastroduodenoscopy. The patient returned the next day with extreme retching, nausea, and vomiting and was admitted for further evaluation. Intravenous fluids, antiemetics, and morphine were started for pain control with no symptomatic improvement. A diagnosis of cannabis hyperemesis syndrome was made based on history of chronic marijuana use and otherwise negative workup. A trial of topical capsaicin, over the epigastric region, was tried that provided dramatic relief within 24 hours. Repeat endoscopic evaluation had no evidence of ulcers, celiac disease, or esophagitis. She was discharged on topical capsaicin and counselled on marijuana abstinence, with no return of symptoms.

Conclusion

Based on the dramatic resolution of symptoms with topical capsaicin, our case supports this promising intervention and provides an alternate approach to antiemetics and narcotics routinely used in patients with cannabis hyperemesis syndrome.

Evaluating the effect of retail marijuana legalization on parent marijuana use frequency and norms in U.S. States with retail marijuana legalization

OBJECTIVES

To examine post-retail marijuana legalization (RML) change in marijuana use frequency and pro-marijuana norms among parents.

METHODS

The Intergenerational Study, a longitudinal panel of parents (N = 668) and children, followed participants from 2002 to 2018, when parents were 27 and 43 years old, respectively. Three quarters of participants (74%) lived in an RML state and 142 (21%) had used marijuana in the 8 years prior to RML. Piecewise growth modelling compared pre- and post-RML slopes of use frequency and pro-marijuana norms.

RESULTS

Frequency of use and pro-marijuana norms increased following legalization in both RML and non-RML states, though norms rose significantly faster in RML states. Growth in use was primarily driven by new users of marijuana. There were no differences in frequency of marijuana use or pro-marijuana norms by race/ethnicity, gender, or education.

CONCLUSIONS

An increase in marijuana use frequency associated with RML among parents poses risk to both parents' well-being and the health of their children. A faster pace of increase in pro-marijuana norms in RML states may signal continued increases in use in the future.

Therapeutic Application of Cannabis in Medicine and Its Relevance to Thoracic Surgery

BACKGROUND

Cannabis is the most commonly used illicit substance in the United States. As cannabis use rises in popularity and its legalization continues to expand, the scientific community must address the controversy between beneficial and adverse effects of cannabis consumption.

METHODS

We performed a comprehensive literature review to study the medicinal and pathologic effects of cannabis use, with emphasis on its association with cancer pathophysiology and thoracic surgery.

RESULTS

We found evidence that cannabis products often contain carcinogenic materials and that their use is associated with the development of certain head and neck cancers, but not lung cancer. Indeed, several in vitro and in vivo studies have demonstrated that cannabis may have a therapeutic role in cancer given the antiproliferative effects of its active compounds such as δ-9-tetrahydrocannabinol. Cannabis-derived products have also been shown to be effective treatments for chronic pain, neuropathy, spasticity, and as antiemetics.

CONCLUSIONS

We acknowledge that additional studies are required to elucidate the long-term effects of cannabis products and that many potential biases and limitations exist in the literature due to self-reporting and limited survey studies. Appropriate stewardship over cannabis use among our patient population will likely determine its full implications in both oncologic and perioperative outcomes.

Adolescent Marijuana Use and Related Risk Behaviors, National Findings From 2015 to 2017

INTRODUCTION

As policies legalizing nonmedical marijuana have increased in states, understanding the implications of marijuana use among adolescents is increasingly important. This study uses nationally representative data to assess behavioral risk factors among students with different patterns of marijuana use.

METHODS

Data from the 2015 and 2017 Youth Risk Behavior Surveys, cross-sectional surveys conducted among a nationally representative sample of students in Grades 9-12 (n=30,389), were used to examine the association between self-reported current marijuana use status and self-report of 30 risk behaviors across 3 domains: substance use, injury/violence, and sexual health. Among current marijuana users, authors assessed differences between established (≥100 lifetime uses) and nonestablished (<100 uses) users. Multivariable models were used to calculate adjusted prevalence ratios. Data were analyzed in 2019.

RESULTS

Current marijuana users (regardless of use pattern) had a significantly greater likelihood of engaging in 27 of the 30 behaviors assessed across the 3 domains than the noncurrent users. Those with established use patterns (versus nonestablished) had a greater risk of lifetime use of most other substances (licit and illicit, including tobacco, alcohol, heroin, misuse of opioids), some injury/violence behaviors (including driving while using marijuana and suicide ideation and attempt), and sexual risk behaviors.

CONCLUSIONS

Both established and nonestablished patterns of adolescent marijuana use are associated with a number of other risky behaviors. In addition to interventions focused on preventing youth initiation of marijuana, clinicians and public health professionals should consider interventions to help adolescents who have nonestablished use patterns to avoid continued, established use.

Role of Cannabis in the Incidence of Myocardial Infarction: A Review

Legalizing cannabis use in various states in the United States has caused increased substance abuse, mostly among young people. There are very little data focussing on marijuana use and myocardial infarction (MI) incidence. The objective of the study is to analyze the published papers for cannabis-induced MI and derive a strong relation between cannabis use and MI and understand the pathophysiology. An online search was conducted in PubMed, Google Scholar, and PubMed Central to find relevant publications examining patients who developed MI due to cannabis use. Out of 32 articles that were identified for this review, 17 are case reports, one is a letter to the editor, eight are observational studies, and six are review articles. Many studies have proposed different mechanisms by which cannabis affects the body. Our study shows that marijuana can precipitate MI even if it is used for the first time. Limited data is available to comment on the mortality of patients after cannabis-induced MI. These findings highlight the necessity for public awareness to prevent the ill-effects of cannabis, especially for teenagers and older people.

Frequency of cannabis use and alcohol-associated adverse effects in a representative sample of U.S. adolescents and youth (2002-2014) a cross-sectional study

Background

While the link between frequent cannabis use and alcohol use disorders is well documented, it is not clear whether alcohol drinkers who use cannabis less frequently are also vulnerable to alcohol use disorders. We estimate the association of frequency of past 12-months cannabis use with alcohol-associated adverse effects variables in the same time frame: alcohol dependence, heavy drinking, driving under alcohol influence, alcohol-related interpersonal problems, use after interpersonal problems, alcohol-related risky behaviors, and alcohol-related legal problems.

Methods

We analyzed data from U.S. individuals aged 12 to 25 years who participated in annual, cross-sectional U.S. National Surveys on Drug Use and Health from 2002 to 2014. Logistic regression models were used to examine the association of cannabis use with six alcohol-associated adverse effects variables. Frequency of cannabis use served as the primary independent variable, and were divided into four categories: frequent use (21–30 days per month), less frequent use (1–20 days per month), no use over the past 12 months, and no lifetime cannabis use. Alcohol dependence and six alcohol-associated adverse effects variables served as our primary outcomes.

Results

The study included 465,090 respondents aged 12 to 25 years, among all past-year cannabis users, (47.5%) were less frequent (1–20 days/month) users. Less frequent cannabis use was highest among male, 15–25-year-olds, and non-Hispanic white 11.8, 84 and 10.6%, respectively. In adjusted models, past-year less frequent cannabis use (1–20 days/month) was significantly associated with past-year alcohol dependence (adjusted odds ratio aOR 5.57, 95% confidence interval (CI) 5.5–6.4); heavy drinking in the past-year (aOR 3.41, 95% CI 3.2–3.5); alcohol-related interpersonal problems in the past-year (aOR 7.33, 95% CI 7.0–7.5); use after interpersonal problems (aOR 5.17, 95% CI 4.8–5.5); alcohol-related risky behaviors (aOR 7.29, 95% CI 7.0–7.5), and, driving under influence of alcohol (aOR 7.19, 95% CI 6.9–7.4). No cannabis use past-year were more likely to report alcohol dependence (aOR 2.81, 95% CI 2.6–3) compared with no lifetime cannabis use.

Conclusion

These findings indicated that within the general population, not only frequent cannabis user (21–30 days per month) but even less frequent cannabis use (1–20 days/month) was significantly associated with past-year alcohol dependence and alcohol-associated adverse effects than no lifetime cannabis use. These adverse alcohol-related outcomes associated with less frequent cannabis use, should be taken under careful consideration in alcohol use disorder treatment setting and policy planning.

State medical marijuana laws, cannabis use and cannabis use disorder among adults with elevated psychological distress

BACKGROUND

Cannabis use and cannabis use disorder are more prevalent in U.S. states with medical marijuana laws (MMLs), as well as among individuals with elevated psychological distress. We investigated whether adults with moderate and serious psychological distress experienced greater levels of cannabis use and/or disorder in states with MMLs compared to states without MMLs.

METHODS

National Survey of Drug Use and Health data (2013-2017) were used to compare past-month cannabis use, daily cannabis use, and cannabis use disorder prevalence among adults with moderate and serious psychological distress in states with versus without MMLs. We executed pooled multivariable logistic regression analyses to test main effects of distress, MMLs and their interaction, after adjustment.

RESULTS

Compared to states without MMLs, states with MMLs had higher adjusted prevalence of past-month use (11.1 % vs. 6.8 %), daily use (4.0 % vs. 2.2 %), and disorder (1.7 % vs. 1.2 %). Adults with moderate and serious psychological distress had greater adjusted odds of any use (AORs of 1.72 and 2.22, respectively) and of disorder (AORs of 2.17 and 2.94, respectively), compared to those with no/mild distress. We did not find evidence of an interaction between MMLs and distress category for any outcome.

CONCLUSIONS

Associations between elevated distress and cannabis use patterns are no greater in states with MML. However, cannabis use is more prevalent in MML states. Thus, higher base rates of cannabis use and disorder among adults with elevated distress are proportionally magnified in these states.

Medical marijuana laws and driving under the influence of marijuana and alcohol

AIMS

Medical marijuana law (MML) enactment in the United States has been associated with increased cannabis use but lower traffic fatality rates. We assessed the possible association of MML and individual-level driving under the influence of cannabis (DUIC) and also under the influence of alcohol (DUIA).

DESIGN AND SETTING

Three cross-sectional U.S. adult surveys: The National Longitudinal Alcohol Epidemiologic Survey (NLAES; 1991-1992), the National Epidemiologic Survey on Alcohol and Related Conditions (NESARC; 2001-2002), and the NESARC-III (2012-2013).

PARTICIPANTS

The total n was 118 497: 41 764, 41 184, and 35 549 from NLAES, NESARC, and NESARC-III, respectively.

MEASUREMENTS

Across the three surveys, similar questions in the Alcohol Use Disorder and Associated Disabilities Interview Schedule assessed DUIC and DUIA. Ever-MML states enacted MML between 1991-1992 and 2012-2013 (overall period). Early-MML states enacted MML between 1991-1992 and 2001-2002 (early period). Late-MML states enacted MML between 2001-2002 and 2012-2013 (late period). MML effects on change in DUIC and DUIA prevalence were estimated using a difference-in-differences specification to compare changes in MML and other states.

FINDINGS

From 1991-1992 to 2012-2013, DUIC prevalence nearly doubled (from 1.02% to 1.92%), increasing more in states that enacted MML than other states (difference-in-differences [DiD] = 0.59%; 95% CI = 0.06%-1.12%). Most change in DUIC prevalence occurred between 2001-2002 and 2012-2013. DUIC prevalence increased more in states that enacted MML 2001-2002 to 2012-2013 than in never-MML states (DiD = 0.77%; 95% CI = -0.05%-1.59%), and in two early-MML states, California (DiD = 0.82; 95% CI = 0.06-1.59) and Colorado (DiD = 1.32; 95% CI = 0.11-2.53). In contrast, DUIA prevalence appeared unrelated to MML enactment.

CONCLUSIONS

Medical marijuana law enactment in US states appears to have been associated with increased prevalence of driving under the influence of cannabis, but not alcohol.

Urinary Acrylonitrile Metabolite Concentrations Before and after Smoked, Vaporized, and Oral Cannabis in Frequent and Occasional Cannabis Users

Cannabis use through smoking, vaping, or ingestion is increasing, but only limited studies have investigated the resulting exposure to harmful chemicals. N-acetyl-S-(2-cyanoethyl)-L-cysteine (2CYEMA), a urinary metabolite of acrylonitrile, a possible carcinogen, is elevated in the urine of past-30-day cannabis users compared to non-cannabis users. Five frequent and five occasional cannabis users smoked and vaped cannabis on separate days; one also consumed cannabis orally. Urine samples were collected before and up to 72 h post dose and urinary 2CYEMA was quantified. We compared 2CYEMA pre-exposure levels, maximum concentration, time at maximum concentration for occasional versus frequent users following different exposure routes, and measured half-life of elimination. Smoking cannabis joints rapidly (within 10 min) increased 2CYEMA in the urine of occasional cannabis users, but not in frequent users. Urine 2CYEMA did not consistently increase following vaping or ingestion in either study group. Cigarette smokers had high pre-exposure concentrations of 2CYEMA. Following cannabis smoking, the half-lives of 2CYEMA ranged from 2.5 to 9.0 h. 2CYEMA is an effective biomarker of cannabis smoke exposure, including smoke from a single cannabis joint, however, not from vaping or when consumed orally. When using 2CYEMA to evaluate exposure in cannabis users, investigators should collect the details about tobacco smoking, route of consumption, and time since last use as possible covariates.

Daily Cannabis Users with Sickle Cell Disease Show Fewer Admissions than Others with Similar Pain Complaints

Introduction: Previous studies have shown that cannabis use is common in adults with sickle cell disease (SCD), and that many patients report using cannabis to treat pain. Methods: We performed a cross-sectional study of adults with SCD and compared daily users of cannabis with others using validated patient-reported measures of pain and quality of life as well as opioid and health care utilization. Results: Daily cannabis users with SCD had worse pain episode severity scores than others (56.7 vs. 48.8, p=0.02) yet had 1.8 fewer annual admissions (p=0.01) and 1.2 fewer annual emergency room (ER) visits (p=0.01), and similar amounts of opioids dispensed to others after matching for age, gender, SCD genotype, hydroxyurea use, and pain impact scores. Conclusions: We show that people with SCD with more severe pain crisis are more likely to use daily cannabis, yet have lower rates of hospital admission and ER use as compared with others with similar disease severity and pain impact. Randomized controlled trials should be performed.

Role for endocannabinoids in early pregnancy: recent advances and the effects of cannabis use

The endocannabinoid system (ECS) is associated with several physiological processes, including reproduction. This system consists of the cannabinoid receptors, endocannabinoid ligands, and enzymes that metabolize and degrade these fatty acids. Recent evidence shows that cannabinoid receptors are expressed in cells of the reproductive system, including endometrial stromal cells, ovaries, and sperm cells. Emerging and recent research suggests that the ECS may play a significant role in reproduction. The endocannabinoid ligands anandamide and 2-arachidonoylglycerol are crucial for successful endometrium decidualization, placental development, and embryo implantation. Alteration in cannabinoid receptor expression or in endocannabinoid homeostasis by excessive intake of cannabis during pregnancy is associated with negative pregnancy outcomes, including preterm birth. The use of medicinal cannabis is becoming more widespread in Western countries, especially in people of reproductive age. Cannabis contains phytocannabinoids, which modulate the ECS, and emerging evidence suggests that phytocannabinoids, through their action on cannabinoid receptors, may have a negative impact on fertility, pregnancy outcome, and fetal health. In this mini-review, we highlight the recent advances in the field, which explore the role of endocannabinoids in early pregnancy and the effects of excessive intake of phytocannabinoids in pregnancy outcomes.

Association of negative financial shocks during the Great Recession with depressive symptoms and substance use in the USA: the CARDIA study

BACKGROUND

The Great Recession of 2008 was marked by large increases in unemployment and decreases in the household wealth of many Americans. In the 21st century, there have also been increases in depressive symptoms, alcohol use and drug use among some groups in the USA. The objective of this analysis is to evaluate the influence of negative financial shocks incurred during the Great Recession on depressive symptoms, alcohol and drug use.

METHODS

We employed a quasi-experimental fixed-effects design, using data from adults enrolled in the Coronary Artery Risk Development in Young Adults (CARDIA) study. Our financial shock predictors were within-person change in employment status, income and debt to asset ratio between 2005 and 2010. Our outcomes were within-person change in depressive symptoms score, alcohol use and past 30-day drug use.

RESULTS

In adjusted models, we found that becoming unemployed and experiencing a drop in income and were associated with an increase in depressive symptoms. Incurring more debts than assets was also associated with an increase in depressive symptoms and a slight decrease in daily alcohol consumption (mL).

CONCLUSION

Our findings suggest that multiple types of financial shocks incurred during an economic recession negatively influence depressive symptoms among black and white adults in the USA, and highlight the need for future research on how economic recessions are associated with health.

Association of Depression With Past-Month Cannabis Use Among US Adults Aged 20 to 59 Years, 2005 to 2016

IMPORTANCE

Despite studies showing that repeated cannabis use may worsen depressive symptoms, the popular media increasingly presents cannabis as beneficial to mental health, and many members of the public view cannabis as beneficial for depression. Therefore, cannabis use among individuals with depression may be becoming more prevalent.

OBJECTIVE

To examine the association of depression with past-month cannabis use among US adults and the time trends for this association from 2005 to 2016.

DESIGN, SETTING, AND PARTICIPANTS

This repeated cross-sectional study used data from 16 216 adults aged 20 to 59 years who were surveyed by the National Health and Nutrition Examination Survey, a national, annual, cross-sectional survey in the United States, between 2005 and 2016. Data analysis was conducted from January to February 2020.

EXPOSURES

Survey year and depression, as indicated by a score of at least 10 on the Patient Health Questionnaire-9.

MAIN OUTCOMES AND MEASURES

Any past-month cannabis use (ie, ≥1 use in the past 30 days) and daily or near-daily past-month cannabis use (ie, ≥20 uses in the past 30 days). Logistic regression was used to examine time trends in the prevalence of cannabis use, depression, and the association between cannabis use and depression from 2005 to 2016.

RESULTS

The final analysis included 16 216 adults, of whom 7768 (weighted percentage, 48.9%) were men, 6809 (weighted percentage, 66.4%) were non-Hispanic White participants, and 9494 (weighted percentage, 65.6%) had at least some college education. They had a weighted mean age of 39.12 (95% CI, 38.23-39.40) years. Individuals with depression had 1.90 (95% CI, 1.62-2.24) times the odds of any past-month cannabis use and 2.29 (95% CI, 1.80-2.92) times the odds of daily or near-daily cannabis use compared with those without depression. The association between cannabis use and depression increased significantly from 2005 to 2016. The odds ratio for depression and any past-month cannabis use increased from 1.46 (95% CI, 1.07-1.99) in 2005 to 2006 to 2.30 (95% CI, 1.82-2.91) in 2015 to 2016. The odds ratio for depression and daily or near-daily past-month cannabis use increased from 1.37 (95% CI, 0.81-2.32) in 2005 to 2006 to 3.16 (95% CI, 2.23-4.48) in 2015 to 2016.

CONCLUSIONS AND RELEVANCE

The findings of this study indicate that individuals with depression are at increasing risk of cannabis use, with a particularly strong increase in daily or near-daily cannabis use. Clinicians should be aware of these trends and the evidence that cannabis does not treat depression effectively when discussing cannabis use with patients.

Association of Recreational Cannabis Laws in Colorado and Washington State With Changes in Traffic Fatalities, 2005-2017

IMPORTANCE

An important consequence of cannabis legalization is the potential increase in the number of cannabis-impaired drivers on roads, which may result in higher rates of traffic-related injuries and fatalities. To date, limited information about the effects of recreational cannabis laws (RCLs) on traffic fatalities is available.

OBJECTIVE

To estimate the extent to which the implementation of RCLs is associated with traffic fatalities in Colorado and Washington State.

DESIGN, SETTING, AND PARTICIPANTS

This ecological study used a synthetic control approach to examine the association between RCLs and changes in traffic fatalities in Colorado and Washington State in the post-RCL period (2014-2017). Traffic fatalities data were obtained from the Fatality Analysis Reporting System from January 1, 2005, to December 31, 2017. Data from Colorado and Washington State were compared with synthetic controls. Data were analyzed from January 1, 2005, to December 31, 2017.

MAIN OUTCOME(S) AND MEASURES

The primary outcome was the rate of traffic fatalities. Sensitivity analyses were performed (1) excluding neighboring states, (2) excluding states without medical cannabis laws (MCLs), and (3) using the enactment date of RCLs to define pre-RCL and post-RCL periods instead of the effective date.

RESULTS

Implementation of RCLs was associated with increases in traffic fatalities in Colorado but not in Washington State. The difference between Colorado and its synthetic control in the post-RCL period was 1.46 deaths per 1 billion vehicle miles traveled (VMT) per year (an estimated equivalent of 75 excess fatalities per year; probability = 0.047). The difference between Washington State and its synthetic control was 0.08 deaths per 1 billion VMT per year (probability = 0.674). Results were robust in most sensitivity analyses. The difference between Colorado and synthetic Colorado was 1.84 fatalities per 1 billion VMT per year (94 excess deaths per year; probability = 0.055) after excluding neighboring states and 2.16 fatalities per 1 billion VMT per year (111 excess deaths per year; probability = 0.063) after excluding states without MCLs. The effect was smaller when using the enactment date (24 excess deaths per year; probability = 0.116).

CONCLUSIONS AND RELEVANCE

This study found evidence of an increase in traffic fatalities after the implementation of RCLs in Colorado but not in Washington State. Differences in how RCLs were implemented (eg, density of recreational cannabis stores), out-of-state cannabis tourism, and local factors may explain the different results. These findings highlight the importance of RCLs as a factor that may increase traffic fatalities and call for the identification of policies and enforcement strategies that can help prevent unintended consequences of cannabis legalization.

Economic Effects of Adolescent to Adult Patterns of Cannabis Use: Full-Time Employment and Employment Stability

Research has yet to examine stability in employment as a function of cannabis use once an individual transitions into full-time work. Using data from the Rochester Youth Development Study, trajectories of cannabis use spanning ages 14 to 30 were identified among a sample of predominantly minorities (>80%; 68% African American). After hard-classifying individuals by patterns of cannabis use, probabilities of full-time employment and conditional probabilities of full-time employment were calculated and compared across patterns of use. Abstention or rare cannabis use was associated with a higher likelihood of full-time employment compared with other cannabis use patterns. Full-time employment stability was high for each pattern of cannabis use (>89%) and differences decreased with age and prior periods of employment. The results indicate that patterns of cannabis use spanning adolescence to adulthood have limited impact on the ability to retain full-time employment once employed and are interpreted in light of growing legalization of cannabis use.

Epigenetic alterations in cytochrome P450 oxidoreductase (Por) in sperm of rats exposed to tetrahydrocannabinol (THC)

As marijuana legalization is increasing, research regarding possible long-term risks for users and their offspring is needed. Little data exists on effects of paternal tetrahydrocannabinol (THC) exposure prior to reproduction. This study determined if chronic THC exposure alters sperm DNA methylation (DNAm) and if such effects are intergenerationally transmitted. Adult male rats underwent oral gavage with THC or vehicle control. Differentially methylated (DM) loci in motile sperm were identified using reduced representation bisulfite sequencing (RRBS). Another cohort was injected with vehicle or THC, and sperm DNAm was analyzed. Finally, THC-exposed and control adult male rats were mated with THC-naïve females. DNAm levels of target genes in brain tissues of the offspring were determined by pyrosequencing. RRBS identified 2,940 DM CpGs mapping to 627 genes. Significant hypermethylation was confirmed (p < 0.05) following oral THC administration for cytochrome P450 oxidoreductase (Por), involved in toxin processing and disorders of sexual development. Por hypermethylation was not observed after THC injection or in the subsequent generation. These results support that THC alters DNAm in sperm and that route of exposure can have differential effects. Although we did not observe evidence of intergenerational transmission of the DNAm change, larger studies are required to definitively exclude this possibility.

Marijuana smoking and markers of testicular function among men from a fertility centre

STUDY QUESTION

Is marijuana smoking associated with semen quality, sperm DNA integrity or serum concentrations of reproductive hormones among subfertile men?

SUMMARY ANSWER

Men who had ever smoked marijuana had higher sperm concentration and count and lower serum FSH concentrations than men who had never smoked marijuana; no differences were observed between current and past marijuana smokers.

WHAT IS KNOWN ALREADY

Studies of marijuana abuse in humans and animal models of exposure to marijuana suggest that marijuana smoking adversely impacts spermatogenesis. Data is less clear for moderate consumption levels and multiple studies have found higher serum testosterone concentrations among marijuana consumers.

STUDY DESIGN, SIZE, DURATION

This longitudinal study included 662 subfertile men enroled at the Massachusetts General Hospital Fertility Center between 2000 and 2017. The men provided a total of 1143 semen samples; 317 men also provided blood samples in which we measured reproductive hormones.

PARTICIPANTS/MATERIALS, SETTING, METHODS

Use of marijuana and other drugs was self-reported at baseline. Standard protocols were followed for measuring semen quality, sex hormones and DNA integrity. We used linear mixed effect models with a random intercept to evaluate the associations of self-reported marijuana smoking at enrolment with semen parameters from subsequently collected samples, and linear regression models for sperm DNA integrity and serum reproductive hormones, while adjusting for confounders including smoking and cocaine use.

MAIN RESULTS AND THE ROLE OF CHANCE

Men who had ever smoked marijuana (N = 365) had significantly higher sperm concentration (62.7 (95% confidence interval: 56.0, 70.3) million/mL) than men who had never smoked marijuana (N = 297) (45.4 (38.6, 53.3) million/mL) after adjusting for potential confounders (P = 0.0003). There were no significant differences in sperm concentration between current (N = 74) (59.5 (47.3, 74.8) million/mL) and past marijuana smokers (N = 291) (63.5 (56.1, 72.0) million/mL; P = 0.60). A similar pattern was observed for total sperm count. Furthermore, the adjusted prevalence of sperm concentration and total sperm motility below WHO reference values among marijuana smokers was less than half that of never marijuana smokers. Marijuana smokers had significantly lower follicle stimulating hormone (FSH) concentrations than never marijuana smokers (-16% (-27%, -4%)) and there were no significant differences between current and past marijuana smokers (P = 0.53). Marijuana smoking was not associated with other semen parameters, with markers of sperm DNA integrity or with reproductive hormones other than FSH. Chance findings cannot be excluded due to the multiple comparisons.

LIMITATIONS, REASONS FOR CAUTION

Our results may not be generalisable to men from the general population. Marijuana smoking was self-reported and there may be misclassification of the exposure.

WIDER IMPLICATIONS OF THE FINDINGS

These findings are not consistent with a deleterious effect of marijuana on testicular function. Whether these findings are reflective of the previously described role of the endocannabinoid system in spermatogenesis or a spurious association requires confirmation in further studies.

STUDY FUNDING/COMPETING INTEREST(S)

The project was funded by grants R01ES009718 and P30ES000002 from the National Institute of Environmental Health Sciences (NIEHS). None of the authors has any conflicts of interest to declare.

TRIAL REGISTRATION NUMBER

N/A.

Medical Reasons for Marijuana Use, Forms of Use, and Patient Perception of Physician Attitudes Among the US Population

BACKGROUND

The use of marijuana for medical purposes is increasing in parallel with expanding legalization and decreased public perception of harm. Despite this increase in use, it is unclear which medical conditions patients are attempting to treat with marijuana and whether they are communicating with medical providers about their use.

OBJECTIVE

To understand the medical reasons for marijuana use, forms of marijuana used for medical purposes, and disclosure of use to physicians.

DESIGN

National, probability-based online survey.

SETTING

The USA, 2017.

PARTICIPANTS

16,280 US adults.

MAIN MEASURE

Proportion of US adults who agreed with a statement.

KEY RESULTS

A total of 9003 participants completed the survey (55% response rate). Five hundred ninety-one (7% of US adults) reported using marijuana for medical purposes. The most common medical reasons for marijuana use were anxiety (49%), insomnia (47%), chronic pain (42%), and depression (39%). The most common forms of use for all medical conditions were smoking and edibles, followed by vaping, concentrate, and topical. We found women were more likely to use marijuana for posttraumatic stress disorder, sleep, anxiety, and migraines. We did not find substantial variation in medical reasons for marijuana use by race. Among those using marijuana for medical purposes, 21% did not have a doctor. Among those with doctors, 33% did not inform them, 28% reported their doctor was neutral on their use, 32% reported their doctor was supportive, and 8% reported their doctor was not supportive. Those who lived in states where medical marijuana was illegal were less likely to disclose use to their doctor.

LIMITATION

The online format of the survey may have caused selection bias. Wording of the questions may have affected interpretation. Doctors were not queried directly, rather participants were asked about their perception of doctor attitudes.

CONCLUSION

Americans are using marijuana to treat medical conditions despite lack of evidence of efficacy.

The Impact of Marijuana on the Cardiovascular System: A Review of the Most Common Cardiovascular Events Associated with Marijuana Use

With the expanded legalization of marijuana, its medical and recreational use have sharply increased over the past decade. A wide array of new forms of cannabis is available on the market today, and the potencies are ten times those of forms previously tested, meaning that the true impact of marijuana on the cardiovascular system remains unclear. Cannabis mainly exerts its effects via the sympathetic and parasympathetic nervous systems, with different doses affecting different cannabinoids receptors. Studies have shown that marijuana plays a role in thrombosis, inflammation, and atherosclerosis. Case reports have linked marijuana use to myocardial infarction, cardiac arrythmias, cardiomyopathies, stroke, and arteritis. Most patients are young, healthy men with no cardiovascular risk factors; however, the patient population is expected to change to include older individuals in the future. The widespread public perception of safety accompanying marijuana use has contributed to its increased use among the elderly, who are the most at risk population for acute cardiovascular events. In this review, we aim to provide a basic understanding of the physiological effects of marijuana on the cardiovascular system and to review the current literature regarding cardiovascular diseases linked to marijuana use in adults.

Initial use of tobacco or marijuana and later use profiles in young adults

INTRODUCTION

Given the relatively limited literature regarding risk factors for progression of alternative tobacco and marijuana use, this study examined initially-used tobacco or marijuana products and psychosocial risk factors such as adverse childhood events (ACEs), mental health (depression, ADHD), and parental substance use, in relation to young adult lifetime and current (past 30-day) tobacco and marijuana use.

METHODS

Using cross-sectional data from a 2014–2016 study of 3418 young adult college students in Georgia, we analyzed lifetime and current use of various tobacco products (cigarettes, cigar products, smokeless tobacco, e-cigarettes, hookah) and marijuana among lifetime tobacco or marijuana users (N=1451) in relation to initially-used product as well as sociodemographic characteristics and psychosocial risk factors.

RESULTS

Multivariable analyses indicated that more products ever used correlated with cigarettes being first used (vs cigars, B=-0.66; e-cigarettes, OR=-1.33; hookah, B=-0.99; and marijuana, B=-1.05; p<0.001), as well as being older (B=0.06), male (B=-0.72) and White (vs Black, B=-0.30; or Asian, B=-0.60), more adverse childhood events (ACEs, B=0.07), and parental marijuana use (B=0.47; p<0.05). Currently-used products correlated with cigarettes being first used (vs cigars, B=-0.18; e-cigarettes, B=-0.37; and hookah, B=-0.18; p<0.05), being younger (B=-0.04), male (B=-0.15), more depressive symptoms (B=0.01), and parental marijuana use (B=0.40; p<0.05). Current cigarette, smokeless tobacco, hookah and marijuana use demonstrated specificity to initially-used products.

CONCLUSIONS

Initially-used products, specifically cigarettes, with well-documented and communicated risks, correlated with using more products subsequently among young adults, underscoring needed research on such risks and risk communication, and early intervention strategies.

Assessing the public health impact of cannabis legalization in Canada: core outcome indicators towards an 'index' for monitoring and evaluation

The legalization of non-medical cannabis use and supply is impending in Canada. This constitutes a major policy change with the declared objective of improving public health outcomes, which requires rigorous monitoring and evaluation. While numerous different aspects associated with legalization will be examined, a focused perspective is required for effective policy evaluation purposes. To these ends, we have identified a set of 10 core indicators associated with cannabis-related risk/harm outcomes-based on current best evidence-that are expected to measure the primary impacts of legalization on public health outcomes. We briefly review these indicators, and their respective data availability in Canada. As ideally an integrated outcome assessment of cannabis legalization's impact on public health will be available, we further propose options to merge the individual indicators into an integrated, weighted 'index', considering their expected relative impact for public health. One possible approach to undertake this is 'multi-criteria decision analysis' as a method to weight the relative indicator impact on public health; alternative approaches are proposed. The integrated 'public health index' for cannabis legalization will allow for scientifically comprehensive, while focused, monitoring and evaluation of the effects of legalization in Canada for the benefits of science and evidence-based policy alike.

A Survey Exploring the Relationship Between Cannabis Use Characteristics and Sexual Function in Men

Introduction

Cannabis is the most commonly used drug in the United States; however, the effects of cannabis use on male sexual function are poorly understood.

Aim

To characterize the contemporary landscape of cannabis use and to assess the associations between male sexual function and the frequency of use, the primary method of consumption, or cannabis chemovar (tetrahydrocannabinol or cannabidiol) among current users.

Methods

We surveyed adults who visited a single cannabis dispensary for baseline demographic information, medical history, cannabis use habits, and sexual function as assessed by the International Index of Erectile Function (IIEF). An IIEF-5 < 21 was considered erectile dysfunction.

Main Outcome Measures

The main outcome measure of the study was male sexual function via the IIEF domain scores.

Results

A total of 325 men completed the survey with a mean age of 46.7 years. 71.1% of the men were Caucasian and 52.6% were married. 13 men (4%) were never users; 29 men (8.9%) used 1–2 times/week; 51 men (15.7%) used 3–5 times/week, and 232 men (71.4%) used 6+ times/week. The average IIEF-5 score was 22.3 with 19.4% of the men having erectile dysfunction. In univariate analysis, men using cannabis more frequently had a higher overall IIEF (65.36 vs 60.52, P = .001), erectile domain (27.32 vs 25.74, P = .03), orgasm domain (9.08 vs 8.12, P < .001), intercourse satisfaction domain (12.42 vs 11.31, P = .006), and overall satisfaction domain (8.11 vs 7.05, P = .002). In multivariable analysis, compared to men who used cannabis 0 times/week, those who used 6 times/week had an increased overall IIEF (69.08 vs 64.64, P-value adjusted = 0.02), intercourse satisfaction domain (P-value adjusted = 0.04), and overall satisfaction domain (P-value adjusted = 0.02). The primary method of consumption (eg, smoking, edibles, etc.) and cannabinoid composition (eg, cannabidiol vs tetrahydrocannabinol dominant) were not associated with sexual function.

Conclusion

We report an association between the increased frequency of cannabis use and increased male sexual function. However, while the increased frequency of use was statistically significant with regard to the IIEF scores, the clinical significance of this is likely low, and selection bias may limit the generalizability of these findings. The method of consumption and cannabis chemovar were not associated with sexual function.

Bhambhvani HP, Kasman AM, Wilson-King G, et al. A Survey Exploring the Relationship Between Cannabis Use Characteristics and Sexual Function in Men. J Sex Med 2020;8:436–445.

Psychotic disorder and cannabis use: Canadian hospitalization trends, 2006-2015

INTRODUCTION

Given the recent and impending changes to the legal status of nonmedical cannabis use in Canada, understanding the effects of cannabis use on the health care system is important for evaluating the impact of policy change. The aim of this study was to examine pre-legalization trends in hospitalizations for mental and behavioural disorders due to the use of cannabis, according to demographics factors and clinical conditions.

METHODS

We assessed the total number of inpatient hospitalizations for psychiatric conditions with a primary diagnosis of a mental or behavioural disorder due to cannabis use (ICD-10-CA code F12) from the Hospital Mental Health Database for ten years spanning 2006 to 2015, inclusive. We included hospitalizations from all provinces and territories except Quebec. Rates (per 100 000 persons) and relative proportions of hospitalizations by clinical condition, age group, sex and year are reported.

RESULTS

Between 2006 and 2015, the rate of cannabis-related hospitalizations in Canada doubled. Of special note, however, is that hospitalizations during this time period for those with the clinical condition code "mental and behavioural disorders due to use of cannabinoids, psychotic disorder" (F12.5) tripled, accounting for almost half (48%) of all cannabis-related hospitalizations in 2015.

CONCLUSION

Further research is required to investigate the reasons for the increase in hospitalizations for cannabis-related psychotic disorder. The introduction of high-potency cannabinoid products and synthetic cannabinoids into the illicit market are considered as possible factors.

The Effects of Marijuana Use on Lumbar Spinal Fusion

MINI: This study compared clinical and patient-reported outcomes following transforaminal lumbar interbody fusion between patients who use or do not use marijuana. We found that patients who use marijuana are younger, but do not demonstrate any differences in preoperative or postoperative Oswestry disability index scores or rates of fusion.

STUDY DESIGN

A retrospective cohort study.

OBJECTIVE

The purpose of this study was to evaluate marijuana usage and its effect on outcomes following transforaminal lumbar interbody fusion (TLIF).

SUMMARY OF BACKGROUND DATA

As marijuana becomes legalized throughout the United States, its medicinal and recreational usage is becoming more mainstream. Clinicians currently have little guidance regarding both short-term and long-term effects of marijuana usage on surgical interventions. While the rate of lumbar spinal fusion in the United States continues to grow, the effect of marijuana usage on fusion remains uncertain.

METHODS

One hundred two patients who underwent TLIF performed by the same surgeon were followed for 12 months. Patients were self-reported for marijuana usage (n = 36). Patient reported outcome measures included preoperative Oswestry disability index (ODI), 6-month ODI, and 12-month ODI, as well as length of stay (LOS), complications, return to operating room (OR), revision surgery, and confirmed fusion. Continuous variables were compared using the independent two-sample t test or analysis of variance (ANOVA), whereas categorical variables were analyzed using the chi-square or Fischer exact tests. Adjusted analysis was performed using a multivariate logistic regression model.

RESULTS

Marijuana usage was associated with a younger population (P < 0.001), but showed no difference regarding sex or body mass index compared with the non-usage group. There was no statistically significant difference in complications, return to OR, or revision surgery between groups. When controlling for factors such as age and preoperative ODI, multivariate analysis demonstrated that marijuana usage did not limit postoperative ODI reduction. The marijuana usage group demonstrated shorter LOS (2.42 vs. 3.00 d, P = 0.020). Fusion rates at 12 months were similar between groups (96% vs. 92.3%, P = 0.678). ODI was similar between groups at all time points.

CONCLUSION

Perioperative outcomes were similar in patients who underwent TLIF regardless of marijuana usage.

LEVEL OF EVIDENCE

3.

Vocal Hygiene in Collegiate Singers-Does Formal Training Relate to Practices?

BACKGROUND

Vocal hygiene is vitally important for protecting vocal quality and promoting vocal longevity. It includes adequate hydration, avoidance of environmental irritants, and refraining from phonotraumatic behaviors such as screaming, excessive talking, and throat clearing. Formal singing training in addition to enhancing singing techniques, is also assumed to promote good vocal hygiene. Consequently, we investigated whether collegiate singers with formal training are more likely to practice good vocal hygiene habits than untrained collegiate singers.

METHODS

We completed a prospective cohort study, where collegiate singers at Stanford University were voluntarily enrolled in an annual vocal health clinic. Full laryngeal exams were performed and demographic information, formal vocal training status, and information on vocal hygiene habits were obtained through questionnaires. The results were then analyzed by grouping singers as "untrained" if less than 1 year of formal training, and "trained" if greater than a year.

RESULTS

A total of 82 singers were included for analysis, with 49 (59.8%) having greater than one year of formal training. Trained singers were more likely to employ a primary musical singing style of classical or operatic singing compared to untrained singers who were more likely to utilize "R&B" (P < 0.001). No significant differences were found between groups for hydration practices (P = 0.20), caffeine consumption (P = 0.73), warm up practices (P = 0.08), and phonotraumatic behaviors. Alcohol consumption, smoking tobacco, marijuana, e-cigarette usage was similar between groups. Overall, 11% of our sample reported intermittent less than daily marijuana use, with one singer reporting daily consumption. None of the singers in this sample used e-cigarettes. These rates are noticeably lower than the agematched United States population. Perceptions of cigarettes, marijuana, electronic cigarettes, alcohol, and caffeine were also the same between groups, with the vast majority of singers perceiving these agents as harmful to the voice (64%-100% depending on the agent). No laryngeal pathology was identified during laryngeal examination of any singers.

CONCLUSIONS

Vocal hygiene habits are similar between trained and untrained collegiate singers. This likely relates to a desire for vocal longevity irrespective of prior training. This may dispel the long-held assumption that formal training was necessary to develop good vocal habits. We do however, present a very homogenous, highly educated sample of collegiate singers from Stanford University, having significantly less at-risk behavior than their aged-matched counterparts in the general US population. A lack of laryngeal pathology despite extensive vocal demands may also be reflective of good vocal hygiene habits.

Is Recovery from Cannabis Dependence Possible? Factors that Help or Hinder Recovery in a National Sample of Canadians with a History of Cannabis Dependence

Objectives

To identify among Canadian adults who have ever been dependent upon cannabis, the prevalence of risk and protective factors associated with (1) cannabis remission, (2) the absence of psychiatric disorders or addictions in the past year (APD), and (3) positive mental health (PMH).

Method

Data from Statistics Canada's nationally representative 2012 Canadian Community Health Survey-Mental Health (n = 20, 777, of whom 336 have a history of cannabis dependence) was used. Chi-square tests and logistic regression analyses were conducted. The World Health Organization Composite International Diagnostic Interview (WHO-CIDI) measures were used to determine lifetime cannabis dependence, past-year remission from cannabis depression, and the absence of psychiatric disorders in the past year (APD) (i.e., no suicidal ideation, depressive episodes, anxiety disorders, bipolar disorders, or any substance dependence). PMH is comprised of three factors: APD, happiness or life satisfaction and social and psychological well-being.

Results

Among those with a history of cannabis dependence, 72% were in remission from cannabis dependence. Although 53% were free of major psychiatric disorders and any substance dependence and 43% of respondents were in PMH, these percentages were dramatically lower than those without a history of cannabis dependence (92% and 74%, respectively). Positive outcomes were more common among women, older respondents, those with higher levels of social support, and those who had never had major depressive disorder or generalized anxiety disorder.

Conclusion

Although many Canadians with a history of cannabis dependence achieve remission and a large minority are truly resilient and achieve PMH, many are failing to thrive. Targeted outreach is warranted for the most vulnerable individuals with a history of cannabis dependence (e.g., men, younger respondents, those with low social support and a history of mental illness).

Cannabis use among youth in the United States, 2004-2016: Faster rate of increase among youth with depression

BACKGROUND

Cannabis use has significant negative consequences for youth. Depression is associated with greater cannabis use among adults but less is known about cannabis use and depression among youth. This study investigated whether depression is associated with increased cannabis use among youth in the United States (US), overall and by demographics, and examined trends in cannabis use by depression status among youth from 2004 to 2016.

METHODS

Data were from the 2004-2016 National Survey on Drug Use and Health (NSDUH), annual cross-sectional national samples of US persons 12 and older. The analytic sample included respondents aged 12-17 (total combined n=204,102). First, the prevalence of past-month cannabis use by past-year depression status among youth was examined, overall and by demographic subgroups, using pooled data from 2004-2016. Next, linear time trends of past-month cannabis use were assessed by depression status from 2004 to 2016 using logistic regression models with continuous year as the predictor. Models with year-by-depression status interaction terms assessed differential time trends for those with and without depression.

RESULTS

From 2004-2016, cannabis use increased both among youth with and without depression. Cannabis use increased significantly more rapidly among youth with (8.45% to 11.65%), compared to without, depression (4.28% to 4.71%). Youth with depression were more than twice as likely to report cannabis use (12.86% versus 6.40%), relative to those without depression.

CONCLUSIONS

Cannabis use was more than twice as common and increased more rapidly from 2004 to 2016 among youth with depression compared to youth without depression.

Modes of marijuana use - smoking, vaping, eating, and dabbing: Results from the 2016 BRFSS in 12 States

BACKGROUND

The prevalence of modes of marijuana use (e.g., smoked, vaped, eaten, dabbed, etc.), and of multi-modal use has not been assessed across multiple states, and can inform marijuana prevention and education work, given that certain modes of use are associated with specific public health risks. This study aimed to assess the prevalence of different modalities of reported marijuana use among adults in 12 states.

METHODS

Data came from 6174 adult marijuana users age 18 and older who responded to questions about past month and mode of marijuana use on the 2016 BRFSS surveys in 12 states with varied state marijuana policies. We used weighted frequencies for descriptive analyses, and logistic regression to identify correlates of multi-modal use.

RESULTS

The prevalence of past month (current) marijuana use among adults in these states was 9.1 % (males = 12.0 %, females= 6.3 %). Among current marijuana users, 33.7 % reported multiple methods of marijuana use, 90.1 % reported any marijuana smoking (e.g., joints, blunts, bongs, bowls), 58.3 % reported only smoking (no other modes of consumption), 24.5 % reported any edible use, 4.5 % reported using only edibles, 19.4 % reported any marijuana vaping, 2.1 % reported only vaping, 14.5 % reported any dabbing (flash vaporization/inhalation of highly concentrated marijuana), and 0.4 % reported only dabbing. Correlates of multimodal use are also examined.

CONCLUSION

Multi-modal use of marijuana is common, and use of non-smoked marijuana (edibles, vaping, dabbing) often occurs in conjunction with other modes of marijuana use. Ongoing surveillance of marijuana modes of use and multi-modal use is warranted to inform public education and prevention.

Vaporization of Marijuana Among Recreational Users: A Qualitative Study

OBJECTIVE

Vaporization of marijuana products, or "vaping," has become a prevalent mode of administration and is typically perceived to hold unique benefits compared to combustible administration methods. Such positive beliefs regarding marijuana vaporization may contribute to its abuse liability. This qualitative study examined cognitions pertaining to vaping among recreational marijuana users.

METHOD

Focus groups were conducted with frequent marijuana users (N = 31; five groups; six to seven per group; M = 5.0 days/week marijuana use). Three topic areas were queried during discussions with the goal of revealing factors that may contribute to the abuse liability of vaporization. These comprised differences between smoking and vaporizing marijuana products, perceived advantages of vaporization, and perceived disadvantages of vaporization. Focus groups lasted approximately 60 minutes and followed a semistructured agenda; the sessions were audio recorded and transcribed for an applied thematic analysis. An executive summary of each group was made and key themes pertaining to vaporization were summarized.

RESULTS

Several themes emerged, including differences between smoking and vaporizing marijuana, convenience, discretion, and efficiency of vaping, perceived health benefits, the absence of traditional smoking rituals, and the high cost of vaporization devices.

CONCLUSIONS

Several factors appear to promote marijuana vaporization, including device aspects (e.g., discreet, convenient), the subjective high, economical efficiency, and perceived harm-reducing and health-promoting effects. These qualitative data highlight unique cognitions about marijuana vaping that may substantially increase its abuse liability. Quantitative research is needed to examine the extent to which cognitions about marijuana vaporization contribute to actual use patterns and problematic behaviors.

Terpenoids, Cannabimimetic Ligands, beyond the Cannabis Plant

Medicinal use of Cannabis sativa L. has an extensive history and it was essential in the discovery of phytocannabinoids, including the Cannabis major psychoactive compound-Δ9-tetrahydrocannabinol (Δ9-THC)-as well as the G-protein-coupled cannabinoid receptors (CBR), named cannabinoid receptor type-1 (CB1R) and cannabinoid receptor type-2 (CB2R), both part of the now known endocannabinoid system (ECS). Cannabinoids is a vast term that defines several compounds that have been characterized in three categories: (i) endogenous, (ii) synthetic, and (iii) phytocannabinoids, and are able to modulate the CBR and ECS. Particularly, phytocannabinoids are natural terpenoids or phenolic compounds derived from Cannabis sativa. However, these terpenoids and phenolic compounds can also be derived from other plants (non-cannabinoids) and still induce cannabinoid-like properties. Cannabimimetic ligands, beyond the Cannabis plant, can act as CBR agonists or antagonists, or ECS enzyme inhibitors, besides being able of playing a role in immune-mediated inflammatory and infectious diseases, neuroinflammatory, neurological, and neurodegenerative diseases, as well as in cancer, and autoimmunity by itself. In this review, we summarize and critically highlight past, present, and future progress on the understanding of the role of cannabinoid-like molecules, mainly terpenes, as prospective therapeutics for different pathological conditions.

Longitudinal associations between marijuana and cigar use in young adults

BACKGROUND

We assess the longitudinal associations between marijuana and cigar (little cigars and cigarillos [LCCs] and large cigars) use on subsequent initiation of marijuana and cigar use.

METHODS

Data are from a cohort study of 2189 young adults recruited in fall 2010 from 11 colleges in the Southeast. We used discrete-time survival analysis to examine whether ever use of marijuana at baseline (spring 2011, freshman year) predicted initiation of LCCs and large cigars and whether ever use of these cigar products predicted initiation of marijuana use across 10 waves of data collection (2011-2018).

RESULTS

The sample was 65.3 % female, 83.6 % White, 5.9 % Hispanic, and 61.8 % had college-educated mothers. At baseline, 70 % reported never using LCCs, 71 % reported never using large cigars, and 74 % reported never using marijuana. Ever use of marijuana at baseline was associated with an increased risk of LCC initiation (Incident rate ratio [IRR] = 1.6, 95 %CI = 1.0, 2.5) but not large cigar initiation. Ever use of LCCs (IRR = 1.4, 95 %CI = 1.1, 1.8) and ever use of large cigars (IRR = 1.3, 95 %CI = 1.1, 1.8) at baseline both predicted initiation of marijuana use.

CONCLUSIONS

Our findings support growing evidence that marijuana and LCCs are strongly associated and use of one substance predicts use of the other. In contrast to studies of adults, we also found that young adults who have tried large cigars may be at increased risk for subsequent marijuana use. These findings highlight the need to consider each product as a potential gateway of the other when developing interventions for young adults.

Pharmacotherapy for the Treatment of Cannabis Use Disorder: A Systematic Review

BACKGROUND

Cannabis use disorder (CUD) is a growing concern, and evidence-based data are needed to inform treatment options.

PURPOSE

To review the benefits and risks of pharmacotherapies for the treatment of CUD.

DATA SOURCES

MEDLINE, PsycINFO, Cochrane Database of Systematic Reviews, and clinical trial registries from inception through September 2019.

STUDY SELECTION

Pharmacotherapy trials of adults or adolescents with CUD that targeted cannabis abstinence or reduction, treatment retention, withdrawal symptoms, and other outcomes.

DATA EXTRACTION

Data were abstracted by 1 investigator and confirmed by a second. Study quality was dually assessed, and strength of evidence (SOE) was determined by consensus according to standard criteria.

DATA SYNTHESIS

Across 26 trials, the evidence was largely insufficient. Low-strength evidence was found that selective serotonin reuptake inhibitors (SSRIs) do not reduce cannabis use or improve treatment retention. Low- to moderate-strength evidence was found that buspirone does not improve outcomes and that cannabinoids do not increase abstinence rates (moderate SOE), reduce cannabis use (low SOE), or increase treatment retention (low SOE). Across all drug studies, no consistent evidence of increased harm was found.

LIMITATIONS

Few methodologically rigorous trials have been done. Existing trials are hampered by small sample sizes, high attrition rates, and heterogeneity of concurrent interventions and outcomes assessment.

CONCLUSION

Although data on pharmacologic interventions for CUD are scarce, evidence exists that several drug classes, including cannabinoids and SSRIs, are ineffective. Because of increasing access to and use of cannabis in the general population, along with a high prevalence of CUD among current cannabis users, an urgent need exists for more research to identify effective pharmacologic treatments.

PRIMARY FUNDING SOURCE

U.S. Department of Veterans Affairs. (PROSPERO: CRD42018108064).

Patterns of Marijuana Use Among Patients With Celiac Disease in the United States: A Population-based Analysis of the NHANES Survey

BACKGROUND

Marijuana use has been assessed in patients with chronic gastrointestinal disorders and may contribute to either symptoms or palliation. Use in those with celiac disease (CD) has not been assessed. Our aim was to evaluate patterns of marijuana use in a large population-based survey among patients with CD, people who avoid gluten (PWAG), and controls.

STUDY

We analyzed data from the National Health and Nutrition Examination Survey from 2009 to 2014. χ tests and multivariable logistic regression were used to compare participants with CD and PWAG to controls regarding the use of marijuana.

RESULTS

Among respondents who reported ever using marijuana (overall 59.1%), routine (at-least monthly) marijuana use was reported by 46% of controls versus 6% of participants with diagnosed CD (P=0.005) and 66% undiagnosed CD as identified on serology (P=0.098) and 51% of PWAG (P=0.536). Subjects with diagnosed CD had lower odds of routine marijuana use compared with controls (odds ratio, 0.08; 95% confidence interval, 0.01-0.73), whereas participants with undiagnosed CD had increased odds of routine use (odds ratio, 2.26; 95% confidence interval, 0.83-6.13), which remained elevated even after adjusting for age, sex, race/ethnicity, health insurance status, alcohol, tobacco use, educational level, and poverty/income ratio.

CONCLUSIONS

In all groups, marijuana use was high. Although there were no differences among subjects with CD, PWAG, and controls who ever used marijuana, subjects with diagnosed CD appear to have decreased routine use of marijuana when compared with controls and PWAG. Those with undiagnosed CD have significantly higher rates of regular use. Future research should focus on the utilization of marijuana as it may contribute to further understanding of symptoms and treatments.

Rural-urban differences in cannabis detected in fatally injured drivers in the United States

While there is a vast literature on rural and urban differences in substance use, little is known in terms of cannabis positive drug tests among fatally injured drivers. In the present study, we examined rural-urban differences in cannabis detected in fatally-injured drivers. Data were drawn from the 2015-2017 Fatality Analysis Reporting System. Multivariable logistic regression was performed to examine rural-urban differences in the percentage of cannabis detected in fatally-injured drivers. Analyses were stratified by rural-urban classification and sex. A positive cannabis test in fatally-injured drivers was more prevalent in urban locations. Compared to fatally-injured drivers in rural locations, urban drivers had higher odds of a positive test for cannabinoids (aOR: 1.21, 95% CI 1.14-1.28). Non-Hispanic Black drivers had higher odds of testing positive for cannabinoids (aOR: 1.43, 95% CI 1.31-1.55). Those aged at least 25 years had lower odds of a positive test for cannabinoids. Drivers involved in a weekend nighttime crash (aOR: 1.14, 95% CI 1.03-1.26) and weekday nighttime (aOR: 1.15, 95% CI 1.05-1.26) had higher odds of testing positive for cannabinoids compared to drivers involved in a weekend daytime crash. Results showed significant rural-urban differences in the prevalence of cannabis detected in fatally-injured drivers.

Role of cannabis in inflammatory bowel diseases

For many centuries, cannabis (marijuana) has been used for both recreational and medicinal purposes. Currently, there are about 192 million cannabis users worldwide, constituting approximately 3.9% of the global population. Cannabis comprises more than 70 aromatic hydrocarbon compounds known as cannabinoids. Endogenous circulating cannabinoids, or endocannabinoids, such as anandamide and 2-arachidonoyl-glycerol, their metabolizing enzymes (fatty acid amide hydrolase and monoacylglycerol lipase) and 2 G-protein coupled cannabinoid receptors, CB1 and CB2, together represent the endocannabinoid system and are present throughout the human body. In the gastrointestinal (GI) tract, the activated endocannabinoid system reduces gut motility, intestinal secretion and epithelial permeability, and induces inflammatory leukocyte recruitment and immune modulation through the cannabinoid receptors present in the enteric nervous and immune systems. Because of the effects of cannabinoids on the GI tract, attempts have been made to investigate their medicinal properties, particularly for GI disorders such as pancreatitis, hepatitis, and inflammatory bowel diseases (IBD). The effects of cannabis on IBD have been elucidated in several small observational and placebo-controlled studies, but with varied results. The small sample size and short follow-up duration in these studies make it difficult to show the clear benefits of cannabis in IBD. However, cannabis is now being considered as a potential drug for inflammatory GI conditions, particularly IBD, because of its spreading legalization in the United States and other countries and the growing trend in its use. More high-quality controlled studies are warranted to elucidate the mechanism and benefits of cannabis use as a possible option in IBD management.

Cannabis Use and Sport: A Systematic Review

CONTEXT

Cannabis use has increased, in large part due to decriminalization. Despite this increase in usage, it remains unclear what proportion of athletes use cannabis and what effect it has on athletic performance and recovery.

OBJECTIVE

To systematically review cannabis use among athletes, including epidemiology, effect on performance and recovery, and regulations for use in sport.

DATA SOURCES

PubMed, MEDLINE, and EMBASE databases were queried from database inception through November 15, 2018. A hand search of policies, official documents, and media reports was performed for relevant information.

STUDY SELECTION

All studies related to cannabis use in athletes, including impact on athletic performance or recovery, were included.

STUDY DESIGN

Systematic review.

LEVEL OF EVIDENCE

Level 4.

DATA EXTRACTION

Demographic and descriptive data of included studies relating to epidemiology of cannabis use in athletes were extracted and presented in weighted means or percentages where applicable.

RESULTS

Overall, 37 studies were included, of which the majority were cross-sectional studies of elite and university athletes. Among 11 studies reporting use among athletes (n = 46,202), approximately 23.4% of respondents reported using cannabis in the past 12 months. Two studies found a negative impact on performance, while another 2 studies found no impact. There was no literature on the influence of cannabis on athletic recovery. Across athletic organizations and leagues, there is considerable variability in acceptable thresholds for urine tetrahydrocannabinol levels (>15 to 150 ng/mL) and penalties for athletes found to be above these accepted thresholds.

CONCLUSION

Overall, these results suggest that approximately 1 in 4 athletes report using cannabis within the past year. Based on the available evidence, cannabis does not appear to positively affect performance, but the literature surrounding this is generally poor. Given the variability in regulation across different sport types and competition levels, as well as the growing number of states legalizing recreational cannabis use, there is a need to improve our understanding of the effects of cannabis use on the athlete and perhaps adopt a clearer and overarching policy for the use of cannabis by athletes in all sports and at all levels.

Women's Questions About Perinatal Cannabis Use and Health Care Providers' Responses

Background: Cannabis use is common among individuals of reproductive age. We examined publicly posted questions about perinatal cannabis use and licensed United States health care provider responses. Materials and Methods: Data were medical questions on perinatal cannabis use posted online from March 2011 to January 2017 on an anonymous digital health platform. Posters were able to "thank" health care providers for their responses and providers could "agree" with other provider responses. We characterized 364 user questions and 596 responses from 277 unique providers and examined endorsement of responses through provider "agrees" and user "thanks." Results: The most frequent questions concerned prenatal cannabis use detection (24.7%), effects on fertility (22.6%), harms of prenatal use to the fetus (21.3%), and risks of baby exposure to cannabis through breast milk (14.4%). Provider sentiment in responses regarding the safety of perinatal cannabis use were coded as 55.6% harmful, 8.8% safe, 8.8% mixed/unsure, and 26.8% safety unaddressed. Half of providers (49.6%) discouraged perinatal cannabis use, 0.5% encouraged use, and 49.9% neither encouraged nor discouraged use. Provider responses received 1,004 provider "agrees" and 583 user "thanks." Provider responses indicating that perinatal cannabis use is unsafe received more provider "agrees" than responses indicating that use is safe (B = 0.42, 95% CI 0.02-0.82, p = 0.04). User "thanks" did not differ by provider responses regarding safety or dis/encouragement. Conclusion: The data indicate public interest in cannabis use effects before, during, and after pregnancy. While most health care providers indicated cannabis use during pregnancy and breastfeeding is not safe, many did not address safety or discourage use, suggesting a missed educational opportunity.