Association Between Marijuana Use and Risk of Cancer: A Systematic Review and Meta-analysis

Secondhand cannabis smoke exposure and respiratory symptoms among adults living in a state with legalized medical cannabis with limited smoke-free protections

Background

Little is known about the demographic and health correlates of secondhand cannabis smoke (SHCS) exposure, despite increased availability and use of cannabis across the U.S. This study examined the prevalence and correlates of SHCS exposure in a sample of N=5,410 adults living in Oklahoma and the association of SHCS exposure with self-reported respiratory problems.

Methods

Data were from a repeated cross-sectional online survey of adults ages 18 and older who completed measurements of past 30-day SHCS exposure in the respondent's home, in a vehicle, and/or in an indoor setting; harm perceptions of SHCS exposure; frequency of current respiratory symptoms; past 30-day use of cannabis, alcohol, and cigarettes.

Results

Almost half (42 %) reported past 30-day SHCS exposure. In bivariate tests, those exposed were male, younger, non-Hispanic (NH) black or Hispanic, reported lower educational and financial attainment, had lower harm perceptions of SHCS exposure, endorsed more respiratory symptoms, and reported past 30-day cannabis and cigarette use (all p's < 0.01). In an adjusted regression model, young adulthood (ages 18-24), NH black race (vs NH White), and past 30-day cigarette smoking and cannabis use emerged as the strongest correlates of SHCS exposure. In interaction models, respiratory symptoms were highest among those reporting past 30-day SHCS exposure and past 30-day cannabis use.

Conclusion

SHCS exposure is common and associated with more frequent respiratory symptoms, particularly among cannabis users. Those exposed were more socially and economically vulnerable.

The Efficacy of Cannabis in Oncology Patient Care and Its Anti-Tumor Effects

As the legalization of medical cannabis expands across several countries, interest in its potential advantages among cancer patients and caregivers is burgeoning. However, patients seeking to integrate cannabis into their treatment often encounter frustration when their oncologists lack adequate information to offer guidance. This knowledge gap is exacerbated by the scarcity of published literature on the benefits of medical cannabis, leaving oncologists reliant on evidence-based data disheartened. This comprehensive narrative article, tailored for both clinicians and patients, endeavors to bridge these informational voids. It synthesizes cannabis history, pharmacology, and physiology and focuses on addressing various symptoms prevalent in cancer care, including insomnia, nausea and vomiting, appetite issues, pain management, and potential anti-cancer effects. Furthermore, by delving into the potential mechanisms of action and exploring their relevance in cancer treatment, this article aims to shed light on the potential benefits and effects of cannabis in oncology.

Cannabis Use and Head and Neck Cancer

Importance

Cannabis is the most commonly used illicit substance worldwide. Whether cannabis use is associated with head and neck cancer (HNC) is unclear.

Objective

To assess the clinical association between cannabis use and HNC.

Design, Setting, and Participants

This large multicenter cohort study used clinical records from a database that included 20 years of data (through April 2024) from 64 health care organizations. A database was searched for medical records for US adults with and without cannabis-related disorder who had recorded outpatient hospital clinic visits and no prior history of HNC. Propensity score matching was performed for demographic characteristics, alcohol-related disorders, and tobacco use. Subsequently, relative risks (RRs) were calculated to explore risk of HNC, including HNC subsites. This analysis was repeated among those younger than 60 years and 60 years or older.

Exposure

Cannabis-related disorder.

Main Outcomes and Measures

Diagnosis of HNC and any HNC subsite.

Results

The cannabis-related disorder cohort included 116 076 individuals (51 646 women [44.5%]) with a mean (SD) age of 46.4 (16.8) years. The non-cannabis-related disorder cohort included 3 985 286 individuals (2 173 684 women [54.5%]) with a mean (SD) age of 60.8 (20.6) years. The rate of new HNC diagnosis in all sites was higher in the cannabis-related disorder cohort. After matching (n = 115 865 per group), patients with cannabis-related disorder had a higher risk of any HNC (RR, 3.49; 95% CI, 2.78-4.39) than those without HNC. A site-specific analysis yielded that those with cannabis-related disorder had a higher risk of oral (RR, 2.51; 95% CI, 1.81-3.47), oropharyngeal (RR, 4.90; 95% CI, 2.99-8.02), and laryngeal (RR, 8.39; 95% CI, 4.72-14.90) cancer. Results were consistent when stratifying by older and younger age group.

Conclusions and Relevance

This cohort study highlights an association between cannabis-related disorder and the development of HNC in adult patients. Given the limitations of the database, future research should examine the mechanism of this association and analyze dose response with strong controls to further support evidence of cannabis use as a risk factor for HNCs.

Latent Trajectories of Persistence of Cannabis Use Across Four Decades in 329 Men From the San Diego Prospective Study

OBJECTIVE

These analyses use data from a 40-year prospective study to extend information into the sixth and seventh decades of life regarding latent trajectory classes of cannabis use and predictors of those classes.

METHOD

Data from the San Diego Prospective Study were analyzed for 329 men of European and Hispanic ethnicity who had used cannabis at about age 23 at study entry (Time 1) and who were interviewed about every 5 years through about age 60 to 70. Latent classes of cannabis use trajectories were evaluated using latent class growth analyses, baseline predictors of class membership were determined, and significant predictors of each class were established using logistic regression analyses.

RESULTS

Four latent classes were identified ranging from 12.5% with cannabis use at every follow-up to 25.8% with no use after Time 1. Eight of 14 Time 1 predictors differed significantly across the trajectory classes, including five (age, marital status, religious identity, intensity of cannabis use, and sensation seeking) that significantly contributed to regression analyses when all significant predictors were considered together.

DISCUSSION

Forty-two percent of participants continued using cannabis long-term, including one in eight who used it at every follow-up. Predictors of continued use and identification of those most likely to stop required gathering information on a range of demographic, prior substance use, and personality characteristics.

CONCLUSIONS

Considering the potential enhanced dangers of cannabis use in later life, the high rate of continued use over four decades implies that clinicians should ask all older patients about recent cannabis use, especially if they had used it in their 20s.

Heavy Lifetime Cannabis Use and Mortality by Sex

Importance

The association between mortality and cannabis use remains unclear.

Objective

To examine sex-stratified associations of cumulative lifetime cannabis use with all-cause, cardiovascular disease (CVD), and cancer mortality in the UK Biobank population.

Design, Setting, and Participants

This cohort study used data from volunteers in the UK Biobank population. Participant monitoring for mortality in the UK Biobank study commenced from the point of their inclusion between 2006 and 2010 and continued until December 19, 2020. Data regarding the causes of death were sourced from the National Health Service Information Centre. Data were analyzed from inception of study inclusion to December 2020.

Exposure

Cannabis use status was assessed by questionnaire and categorized as heavy, moderate, low, and never.

Main Outcomes and Measures

The main outcomes were all-cause, CVD, and cancer mortality. Sex-stratified associations of cumulative lifetime cannabis use with mortality were estimated using Cox proportional hazards regression with adjustment for demographic and clinical variables.

Results

Among 121 895 participants (54.51% females with mean [SD] age of 55.15 [7.64] years; 45.49% males with mean [SD] age of 56.46 [7.79] years) during an overall median of 11.80 years (IQR, 10.53-13.22 years) of follow-up, 2375 total deaths occurred, including 1411 deaths from CVD and 440 from cancer. In males, after full adjustment, the hazard ratios (HRs) were 1.28 (95% CI, 0.90-1.81) for all-cause mortality, 0.98 (95% CI, 0.43-2.25) for CVD mortality, and 1.09 (95% CI, 0.71-1.67) for cancer mortality among heavy cannabis users compared with never users. In females, after full adjustment, the HRs were 1.49 (95% CI, 0.92-2.40) for all-cause mortality, 2.67 (95% CI, 1.19-4.32) for CVD mortality, and 1.61 (95% CI, 0.91-2.83) for cancer mortality among heavy cannabis users compared with never users. In female current tobacco users, after full adjustment, heavy cannabis use was associated with all-cause mortality (HR, 2.25; 95% CI, 1.12-4.53), CVD mortality (HR, 2.56; 95% CI, 1.43-15.36), and cancer mortality (HR, 3.52; 95% CI, 1.50-8.33) and among never tobacco users was associated with CVD mortality (HR, 2.98; 95% CI, 1.67-6.61). In male current tobacco users, heavy cannabis use was associated with cancer mortality (HR, 2.44; 95% CI, 1.14-5.23).

Conclusions and Relevance

In this study, a positive association between CVD mortality and heavy lifetime cannabis use was observed among females. Longitudinal studies are needed in general populations to investigate the potential effects of cannabis on mortality.

Does cannabis elevate cancer risk? : Evidence from Mendelian randomization

BACKGROUND

Cannabis use is increasing annually but the relationship between cannabis use and cancer incidence is not uniform because of confounding factors. We aimed to assess the effect of cannabis use on cancer risk using a two-sample Mendelian randomization (MR) approach.

METHODS

Secondary data analyses were performed on pooled data based on Genome-Wide Association Study (GWAS), selecting data from the ICC and UK-Biobank and 23andMeInc lifetime cannabis use and cannabis use disorder related to the substance use disorders working group from the Psychiatric Genomics Consortium, then selecting highly correlated SNPs as instrumental variables. The substance use disorders working group, iPSYCH, and deCODE GWAS data, and then highly correlated SNPs were selected as instrumental variables for two-sample Mendelian randomization analyses using inverse variance weighting, MR-Egger regression, and weighted median, respectively, to evaluate the relationship between lifetime cannabis use and nine tumors, and subsequently analyzed these results in the same way using cannabis use disorders.

RESULTS

The risk of all cancers except breast cancer was not associated with lifetime cannabis use. Our inverse variance weighting method found that lifetime marijuana use reduced the breast cancer risk (P = 0.016, odds ratio [OR] = 0.981), and we subsequently conducted analyses of cannabis use disorders and cancer risk, which showed that cannabis use disorders elevated the risk of breast cancer (P = 0.007, OR = 1.007) as well as the risk of lung cancer (P = 0.014, OR = 1.122).

CONCLUSION

Large MR analyses suggest that lifetime cannabis use may reduce breast cancer risk, but cannabis use disorder exacerbates the risk of breast and lung cancer. The mechanisms responsible for this outcome remain to be investigated.

Marijuana Use May Be Associated with Reduced Prevalence of Prostate Cancer: A National Survey on Drug Use and Health Study from United States of America

Preclinical evidence indicates the potential anti-tumor capabilities of cannabinoids in prostate cancer (PC). We undertook a cross-sectional study using National Survey on Drug Use and Health data from 2002 to 2020, involving 2503 participants in the USA. The independent variable was marijuana use status (current, former, never), while the dependent variable was self-reported PC (yes, no). Eleven other demographic variables were assessed as covariates. PC prevalence was lower among current marijuana users (46/145, 31.7%) and former users (323/1021, 31.6%) compared to non-users (534/1337, 39.9%, p < 0.001). PC prevalence was lower among users versus non-users in the elderly (≥65) (36.4% vs. 42.4%, p = 0.016) and non-Hispanic white subgroups (28.9% vs. 38.3%, p < 0.001). There were no significant PC prevalence differences between users and non-users in the younger population (50-64) or other race/ethnicity. In the multivariable analyses, former marijuana use was associated with lower PC compared to never using (odd ratio = 0.74, 95% CI 0.62-0.90, p = 0.001). Current use was also suggestive of reduced prevalence but was not statistically significant (odd ratio = 0.77, 95% CI 0.52-1.14, p = 0.198), possibly due to low sample size. Our findings from a large national survey provide additional data to link marijuana use with lower PC prevalence.

Cannabis and Cannabinoids in Adults With Cancer: ASCO Guideline

PURPOSE

To guide clinicians, adults with cancer, caregivers, researchers, and oncology institutions on the medical use of cannabis and cannabinoids, including synthetic cannabinoids and herbal cannabis derivatives; single, purified cannabinoids; combinations of cannabis ingredients; and full-spectrum cannabis.

METHODS

A systematic literature review identified systematic reviews, randomized controlled trials (RCTs), and cohort studies on the efficacy and safety of cannabis and cannabinoids when used by adults with cancer. Outcomes of interest included antineoplastic effects, cancer treatment toxicity, symptoms, and quality of life. PubMed and the Cochrane Library were searched from database inception to January 27, 2023. ASCO convened an Expert Panel to review the evidence and formulate recommendations.

RESULTS

The evidence base consisted of 13 systematic reviews and five additional primary studies (four RCTs and one cohort study). The certainty of evidence for most outcomes was low or very low.

RECOMMENDATIONS

Cannabis and/or cannabinoid access and use by adults with cancer has outpaced the science supporting their clinical use. This guideline provides strategies for open, nonjudgmental communication between clinicians and adults with cancer about the use of cannabis and/or cannabinoids. Clinicians should recommend against using cannabis or cannabinoids as a cancer-directed treatment unless within the context of a clinical trial. Cannabis and/or cannabinoids may improve refractory, chemotherapy-induced nausea and vomiting when added to guideline-concordant antiemetic regimens. Whether cannabis and/or cannabinoids can improve other supportive care outcomes remains uncertain. This guideline also highlights the critical need for more cannabis and/or cannabinoid research.Additional information is available at www.asco.org/supportive-care-guidelines.

Cardiovascular and Respiratory Effects of Cannabis Use by Route of Administration: A Systematic Review

Aim: Knowledge of the cardiovascular and respiratory effects of cannabis use by route of administration is unclear. This evidence is necessary to increase clinical and public health awareness given the recent trend in cannabis legalization, normalization, and surge in the availability and usage of various forms of cannabis products. Methods: Search was conducted in Web of Science, ProQuest, Psych INFO, Scopus, Embase, and Medline databases, and subsequently in the references of retrieved articles. Peer-reviewed articles published between 2009 and 2023, that reported on cardiovascular and respiratory effects of cannabis use by route of administration were included. Studies with no report of the route of administration and combined use of other illicit substances were excluded. The review was guided by Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) guidelines. Results: Of the 1873 articles retrieved, 42 met inclusion criteria encompassing six case reports, 21 reviews, and 15 empirical studies. Four administration routes were identified: smoking, vaping, oral ingestion, and dabbing. Smoking was the most common route of administration and was associated with both respiratory effects, such as bronchitis, dyspnea, and chronic obstructive lung disease, and cardiovascular effects including tachycardia, ventricular arrhythmias, and myocardial infarction. Cannabis edibles were associated with minimal respiratory effects. Tachycardia was the most common cardiovascular effect and was associated with all routes of administration. Conclusion: Cannabis use does cause cardiovascular and respiratory effects, but the conclusion remains tentative of the cardiovascular and respiratory effects by route of administration due to methodological limitations of the studies.

Testicular cancer in 2023: Current status and recent progress

Testicular germ cell tumor (GCT) is the most common solid tumor in adolescent and young adult men. Progress in the management of GCT has been made in the last 50 years, with a substantial improvement in cure rates for advanced disease, from 25% in the 1970s to nearly 80%. However, relapsed or platinum-refractory disease occurs in a proportion, 20% of whom will die from disease progression. This article reviews the current evidence-based treatments for extracranial GCT, the acute and chronic toxic effects that may result, and highlights contemporary advances and progress in the field.

Adverse Impact of Cannabis on Human Health

Cannabis, the most commonly used recreational drug, is illicit in many areas of the world. With increasing decriminalization and legalization, cannabis use is increasing in the United States and other countries. The adverse effects of cannabis are unclear because its status as a Schedule 1 drug in the United States restricts research. Despite a paucity of data, cannabis is commonly perceived as a benign or even beneficial drug. However, recent studies show that cannabis has adverse cardiovascular and pulmonary effects and is linked with malignancy. Moreover, case reports have shown an association between cannabis use and neuropsychiatric disorders. With growing availability, cannabis misuse by minors has led to increasing incidences of overdose and toxicity. Though difficult to detect, cannabis intoxication may be linked to impaired driving and motor vehicle accidents. Overall, cannabis use is on the rise, and adverse effects are becoming apparent in clinical data sets.

Role of Cannabinoids in Oral Cancer

Cannabinoids have incited scientific interest in different conditions, including malignancy, due to increased exposure to cannabis. Furthermore, cannabinoids are increasingly used to alleviate cancer-related symptoms. This review paper aims to clarify the recent findings on the relationship between cannabinoids and oral cancer, focusing on the molecular mechanisms that could link cannabinoids with oral cancer pathogenesis. In addition, we provide an overview of the current and future perspectives on the management of oral cancer patients using cannabinoid compounds. Epidemiological data on cannabis use and oral cancer development are conflicting. However, in vitro studies assessing the effects of cannabinoids on oral cancer cells have unveiled promising anti-cancer features, including apoptosis and inhibition of cell proliferation. Downregulation of various signaling pathways with anti-cancer effects has been identified in experimental models of oral cancer cells exposed to cannabinoids. Furthermore, in some countries, several synthetic or phytocannabinoids have been approved as medical adjuvants for the management of cancer patients undergoing chemoradiotherapy. Cannabinoids may improve overall well-being by relieving anxiety, depression, pain, and nausea. In conclusion, the link between cannabinoid compounds and oral cancer is complex, and further research is necessary to elucidate the potential risks or their protective impact on oral cancer.

Assessment of prevalence, predictors, reasons and regulations of substance smoking among children in Ghana

BACKGROUND

In Ghana, it is against the law for children to smoke. Nevertheless, a portion of children in the country do smoke. However, there is a paucity of research on young smokers in Ghana and other sub-Saharan African nations. This study, therefore, investigated the prevalence of smoking, the kinds of substances children smoke, predictors of smoking, reasons for and factors that lead children to smoke, and regulation of smoking among children in Ghana.

METHODS

In total, 5024 children aged 8-17 were studied using a cross-sectional convergent parallel mixed method. Descriptive statistics, Person's Chi-square test, Fisher Exact test, and binary logistic regression were used to analyse the quantitative data. In contrast, thematic analysis was used to analyse the qualitative data.

RESULTS

The results showed that 3.2% of children had ever smoked. Male children smoked more often than female children. The prevalence of cigarette, marijuana, and shisha smoking was 78.3%, 18%, and 3.7%, respectively. While more male children than female children smoked cigarettes and marijuana, more female children than male children used shisha. Children mainly smoked for fun and due to group culture. In addition, children were influenced by friends; parents, family members, and neighbours who smoke; curiosity; and advertisements and videos to initiate smoking. Despite the availability of regulations and laws regulating tobacco products in public places, tobacco advertisement, promotion, and sale to persons under 18, children are still smoking.

CONCLUSIONS

Children who have ever engaged in smoking reported using cigarettes, marijuana, and shisha. Policymakers urgently need to strategise and strengthen their policies, programmes, and interventions to address smoking among children.

Association between cannabis use and risk of diabetes mellitus type 2: A systematic review and meta-analysis

BACKGROUND

Cannabis consumption exerts multiple effects on metabolism via various pathways, including glucose regulation and insulin secretion. Studies concerning the association between cannabis use and diabetes mellitus type 2 are discrepant.

OBJECTIVE

This study was conducted to evaluate the association between cannabis use and type 2 diabetes mellitus (T2DM).

SEARCH METHODS

We searched PubMed, Scopus, Embase, Proquest, Web of Science, and Cochrane Library with no time, language or study types restriction until July 1, 2022, using various forms of "cannabis" and "diabetes mellitus" search terms.

SELECTION CRITERIA

Randomized control trials, cohort, and case-control studies investigating the relationship between cannabis consumption and diabetes mellitus type 2 were included.

DATA COLLECTION AND ANALYSIS

The Newcastle-Ottawa scale was used to assess the quality of studies. We pooled odds ratio (OR) with 95% confidence interval (CI) using the random-effects model, generic inverse variance method, DerSimonian and Laird approach.

MAIN RESULTS

A meta-analysis of seven studies, containing 11 surveys and 4 cohorts, revealed that the odds of developing T2DM in individuals exposed to cannabis was 0.48 times (95% CI: 0.39 to 0.59) lower than in those without cannabis exposure.

CONCLUSIONS

A protective effect of cannabis consumption on the odds of diabetes mellitus type 2 development has been suggested. Yet given the considerable interstudy heterogeneity, the upward trend of cannabis consumption and cannabis legalization is recommended to conduct studies with higher levels of evidence.

The Acute Exposure of Human Adult Testis Tissue to Cannabinoids THC and CBD Does Not Impact Testosterone Production Nor Germ Cell Lineage

PURPOSE

While an increased risk of developing germ cell tumors has been established in regular cannabis consumers, there is conflicting evidence about an association between cannabis use and testosterone levels in those regular consumers. In this context, we aimed to determine whether Δ9-tetrahydrocannabinol (THC) and cannabidiol (CBD), the two major and best-studied cannabinoids present in cannabis, also the most used for therapeutic applications, can directly impact the steroidogenic function and germ cell lineage of the human adult testis.

MATERIALS AND METHODS

We used our well-characterized organotypic culture of human testis, in which adult testis explants were exposed to CBD, THC, or CBD/THC [ratio 1:1] from 10-9 to 10-5 M for up to either 48 hours or 9 days of culture. The testes were obtained from multi-organ donors (n=13; mean age: 55.15±5.62 y).

RESULTS

The testosterone production and the spatial distribution of Leydig cells did not change upon CBD and/or THC exposure versus controls after 48 hours or 9 days. The overall tissue morphology of the cannabinoids-exposed testis explants was similar to their control upon 24 hours or 9 days of exposure, a finding confirmed by morphometric analyses on short-term cultures. In line, the number of apoptotic cells was not affected by either 48 hours or 9 days of cannabinoids treatment versus mock. Cannabinoids had no impact on the number of proliferating cells nor on mRNA expression of genes encoding proteins involved in germ cell differentiation, meiosis, or Sertoli and Leydig functions after 24 hours exposure.

CONCLUSIONS

Altogether, these findings show an absence of acute direct effects of exposure to cannabis-derived cannabinoids THC and CBD on testicular testosterone production and germ cells ex vivo. Further studies are warranted to explore an indirect impact of cannabinoids on testis functions through the hypothalamic-pituitary-testis axis, as well as the potential effects of long-term exposures.

Cannabis use among recently treated cancer patients: perceptions and experiences

PURPOSE

To characterize cannabis use among cancer patients, we aimed to describe 1) patterns of cannabis use across multiple cancer sites; 2) perceived goals, benefits, harms of cannabis; and 3) communication about cannabis.

METHODS

Patients with 9 different cancers treated at Memorial Sloan Kettering Cancer Center between March and August 2021 completed an online or phone survey eliciting cannabis use, attitudes, and communication about cannabis. Multivariable logistic regression estimated the association of cancer type and cannabis use, adjusting for sociodemographic characteristics and prior cannabis use.

RESULTS

Among 1258 respondents, 31% used cannabis after diagnosis, ranging from 25% for lung cancer to 59% for testicular cancer. Characteristics associated with cannabis use included younger age, lower education level, and cancer type. In multivariable analysis, compared to lung cancer patients, gastrointestinal cancer patients were more likely to use cannabis (odds ratio [OR] 2.64, 95% confidence interval [CI] 1.25-5.43). Cannabis use in the year prior to diagnosis was strongly associated with cannabis use after diagnosis (OR 19.13, 95% CI 11.92-30.72). Among users, reasons for use included difficulty sleeping (48%); stress, anxiety, or depression (46%); and pain (42%). Among respondents who used cannabis to improve symptoms, 70-90% reported improvement; < 5% reported that any symptom worsened. Only 25% discussed cannabis with healthcare providers.

CONCLUSIONS

Almost a third of cancer patients use cannabis, largely for symptom management. Oncologists may not know about their patients' cannabis use. To improve decision making about cannabis use during cancer care, research is needed to determine benefits and harms of cannabis use.

Balancing risks and benefits of cannabis use: umbrella review of meta-analyses of randomised controlled trials and observational studies

OBJECTIVE

To systematically assess credibility and certainty of associations between cannabis, cannabinoids, and cannabis based medicines and human health, from observational studies and randomised controlled trials (RCTs).

DESIGN

Umbrella review.

DATA SOURCES

PubMed, PsychInfo, Embase, up to 9 February 2022.

ELIGIBILITY CRITERIA FOR SELECTING STUDIES

Systematic reviews with meta-analyses of observational studies and RCTs that have reported on the efficacy and safety of cannabis, cannabinoids, or cannabis based medicines were included. Credibility was graded according to convincing, highly suggestive, suggestive, weak, or not significant (observational evidence), and by GRADE (Grading of Recommendations, Assessment, Development and Evaluations) (RCTs). Quality was assessed with AMSTAR 2 (A Measurement Tool to Assess Systematic Reviews 2). Sensitivity analyses were conducted.

RESULTS

101 meta-analyses were included (observational=50, RCTs=51) (AMSTAR 2 high 33, moderate 31, low 32, or critically low 5). From RCTs supported by high to moderate certainty, cannabis based medicines increased adverse events related to the central nervous system (equivalent odds ratio 2.84 (95% confidence interval 2.16 to 3.73)), psychological effects (3.07 (1.79 to 5.26)), and vision (3.00 (1.79 to 5.03)) in people with mixed conditions (GRADE=high), improved nausea/vomit, pain, spasticity, but increased psychiatric, gastrointestinal adverse events, and somnolence among others (GRADE=moderate). Cannabidiol improved 50% reduction of seizures (0.59 (0.38 to 0.92)) and seizure events (0.59 (0.36 to 0.96)) (GRADE=high), but increased pneumonia, gastrointestinal adverse events, and somnolence (GRADE=moderate). For chronic pain, cannabis based medicines or cannabinoids reduced pain by 30% (0.59 (0.37 to 0.93), GRADE=high), across different conditions (n=7), but increased psychological distress. For epilepsy, cannabidiol increased risk of diarrhoea (2.25 (1.33 to 3.81)), had no effect on sleep disruption (GRADE=high), reduced seizures across different populations and measures (n=7), improved global impression (n=2), quality of life, and increased risk of somnolence (GRADE=moderate). In the general population, cannabis worsened positive psychotic symptoms (5.21 (3.36 to 8.01)) and total psychiatric symptoms (7.49 (5.31 to 10.42)) (GRADE=high), negative psychotic symptoms, and cognition (n=11) (GRADE=moderate). In healthy people, cannabinoids improved pain threshold (0.74 (0.59 to 0.91)), unpleasantness (0.60 (0.41 to 0.88)) (GRADE=high). For inflammatory bowel disease, cannabinoids improved quality of life (0.34 (0.22 to 0.53) (GRADE=high). For multiple sclerosis, cannabinoids improved spasticity, pain, but increased risk of dizziness, dry mouth, nausea, somnolence (GRADE=moderate). For cancer, cannabinoids improved sleep disruption, but had gastrointestinal adverse events (n=2) (GRADE=moderate). Cannabis based medicines, cannabis, and cannabinoids resulted in poor tolerability across various conditions (GRADE=moderate). Evidence was convincing from observational studies (main and sensitivity analyses) in pregnant women, small for gestational age (1.61 (1.41 to 1.83)), low birth weight (1.43 (1.27 to 1.62)); in drivers, car crash (1.27 (1.21 to 1.34)); and in the general population, psychosis (1.71 (1.47 to 2.00)). Harmful effects were noted for additional neonatal outcomes, outcomes related to car crash, outcomes in the general population including psychotic symptoms, suicide attempt, depression, and mania, and impaired cognition in healthy cannabis users (all suggestive to highly suggestive).

CONCLUSIONS

Convincing or converging evidence supports avoidance of cannabis during adolescence and early adulthood, in people prone to or with mental health disorders, in pregnancy and before and while driving. Cannabidiol is effective in people with epilepsy. Cannabis based medicines are effective in people with multiple sclerosis, chronic pain, inflammatory bowel disease, and in palliative medicine but not without adverse events.

STUDY REGISTRATION

PROSPERO CRD42018093045.

FUNDING

None.

Perceptions of Safety of Daily Cannabis vs Tobacco Smoking and Secondhand Smoke Exposure, 2017-2021

Importance

While rates of cigarette use are declining, more US adults are using cannabis. Perceptions of safety are important drivers of substance use and public policy; however, little is known about the comparative views of US adults on tobacco and cannabis safety.

Objective

To compare public perceptions of safety of cannabis vs tobacco smoke and evaluate how perceptions may be changing over time.

Design, Setting, and Participants

This longitudinal survey study was conducted using a web-based survey administered in 2017, 2020, and 2021. US adults participating in Ipsos KnowledgePanel, a nationally representative, population-based survey panel, were included. Data were analyzed from March 2021 through June 2023.

Main Outcomes and Measures

Two questions directly compared the perception of safety of cannabis vs tobacco in terms of daily smoking and secondhand smoke exposure. Additional questions assessed perceptions of safety of secondhand tobacco smoke for adults, children, and pregnant women, with an analogous set of questions for secondhand cannabis smoke.

Results

A total of 5035 participants (mean [SD] age, 53.4 [16.2] years; 2551 males [50.7%]) completed all 3 surveys and provided responses for tobacco and cannabis risk questions. More than one-third of participants felt that daily smoking of cannabis was safer than tobacco, and their views increasingly favored safety of cannabis vs tobacco over time (1742 participants [36.7%] in 2017 vs 2107 participants [44.3%] in 2021; P < .001). The pattern was similar for secondhand cannabis smoke, with 1668 participants (35.1%) responding that cannabis was safer than tobacco in 2017 vs 1908 participants (40.2%) in 2021 (P < .001). Participants who were younger (adjusted odds ratio [aOR] for ages 18-29 years vs ≥60 years, 1.4 [95% CI, 1.1-1.8]; P = .01) or not married (aOR, 1.2 [95% CI, 1.0-1.4]; P = .01) were more likely to move toward safer views of cannabis use over time, while those who were retired (aOR vs working, 0.8 [95% CI, 0.7-0.9]; P = .01) were less likely to move toward a safer view of cannabis. Participants were also more likely to rate secondhand smoke exposure to cannabis vs tobacco as completely or somewhat safe in adults (629 participants [12.6%] vs. 119 participants [2.4%]; P < .001), children (238 participants [4.8%] vs. 90 participants [1.8%]; P < .001), and pregnant women (264 participants [5.3%] vs. 69 participants [1.4%]; P < .001).

Conclusions and Relevance

This study found that US adults increasingly perceived daily smoking and secondhand exposure to cannabis smoke as safer than tobacco smoke from 2017 to 2021. Given that these views do not reflect the existing science on cannabis and tobacco smoke, the findings may have important implications for public health and policy as the legalization and use of cannabis increase.

Cannabis- and Substance-Related Carcinogenesis in Europe: A Lagged Causal Inferential Panel Regression Study

Recent European data facilitate an epidemiological investigation of the controversial cannabis-cancer relationship. Of particular concern were prior findings associating high-dose cannabis use with reproductive problems and potential genetic impacts. Cancer incidence data age-standardised to the world population was obtained from the European Cancer Information System 2000-2020 and many European national cancer registries. Drug use data were obtained from the European Monitoring Centre for Drugs and Drug Addiction. Alcohol and tobacco consumption was sourced from the WHO. Median household income was taken from the World bank. Cancer rates in high-cannabis-use countries were significantly higher than elsewhere (β-estimate = 0.4165, p = 3.54 × 10^-115). Eighteen of forty-one cancers (42,675 individual rates) were significantly associated with cannabis exposure at bivariate analysis. Twenty-five cancers were linked in inverse-probability-weighted multivariate models. Temporal lagging in panel models intensified these effects. In multivariable models, cannabis was a more powerful correlate of cancer incidence than tobacco or alcohol. Reproductive toxicity was evidenced by the involvement of testis, ovary, prostate and breast cancers and because some of the myeloid and lymphoid leukaemias implicated occur in childhood, indicating inherited intergenerational genotoxicity. Cannabis is a more important carcinogen than tobacco and alcohol and fulfills epidemiological qualitative and quantitative criteria for causality for 25/41 cancers. Reproductive and transgenerational effects are prominent. These findings confirm the clinical and epidemiological salience of cannabis as a major multigenerational community carcinogen.

Should oncologists trust cannabinoids?

Cannabis enjoyed a "golden age" as a medicinal product in the late 19th, early 20th century, but the increased risk of overdose and abuse led to its criminalization. However, the 21st century have witnessed a resurgence of interest and a large body of literature regarding the benefits of cannabinoids have emerged. As legalization and decriminalization have spread around the world, cancer patients are increasingly interested in the potential utility of cannabinoids. Although eager to discuss cannabis use with their oncologist, patients often find them to be reluctant, mainly because clinicians are still not convinced by the existing evidence-based data to guide their treatment plans. Physicians should prescribe cannabis only if a careful explanation can be provided and follow up response evaluation ensured, making it mandatory for them to be up to date with the positive and also negative aspects of the cannabis in the case of cancer patients. Consequently, this article aims to bring some clarifications to clinicians regarding the sometimes-confusing various nomenclature under which this plant is mentioned, current legislation and the existing evidence (both preclinical and clinical) for the utility of cannabinoids in cancer patients, for either palliation of the associated symptoms or even the potential antitumor effects that cannabinoids may have.

Effects of Smoking Marijuana on the Respiratory System: A Systematic Review

BACKGROUND

The prevalence of marijuana use and its derivatives has surged over the past century, largely due to increasing legalization globally. Despite arguments advocating its benefits, marijuana smoking exposes the lungs to harmful combustion byproducts, leading to various respiratory issues such as asthma, pneumonia, emphysema, and chronic obstructive pulmonary disease.

METHODS

We embarked on an extensive literature search, utilizing PubMed/Medline, Scopus, Web of Science, and Google Scholar databases, identifying 200 studies. After the elimination of duplicates, and meticulous review of abstracts and full texts, 55 studies were included in our analysis.

RESULTS

Current literature demonstrates that marijuana use negatively impacts lung function, triggering symptoms like chronic cough, sputum production, and wheezing, and diminishing FEV1/FVC ratio in spirometry tests. Moreover, prolonged or chronic marijuana use augments the risk of respiratory function impairment. While the carcinogenic effects of marijuana are still contested, a weak correlation between marijuana use and lung cancer has been observed in some studies. Additionally, instances of other pathologies linked to marijuana use have been reported, including the development of COPD, pulmonary bullae, spontaneous pneumothorax, pleuritic pain, chronic pulmonary aspergillosis, hemoptysis, and pulmonary Langerhans cell histiocytosis.

CONCLUSIONS

The evidence underscores that marijuana use is detrimental to respiratory health. In light of the escalating trend of marijuana use, particularly among the youth, it is imperative to advocate public health messages discouraging its consumption.

Pleiotropic loci for cannabis use disorder severity in multi-ancestry high-risk populations

Cannabis use disorder (CUD) is common and has in part a genetic basis. The risk factors underlying its development likely involve multiple genes that are polygenetic and interact with each other and the environment to ultimately lead to the disorder. Co-morbidity and genetic correlations have been identified between CUD and other disorders and traits in select populations primarily of European descent. If two or more traits, such as CUD and another disorder, are affected by the same genetic locus, they are said to be pleiotropic. The present study aimed to identify specific pleiotropic loci for the severity level of CUD in three high-risk population cohorts: American Indians (AI), Mexican Americans (MA), and European Americans (EA). Using a previously developed computational method based on a machine learning technique, we leveraged the entire GWAS catalog and identified 114, 119, and 165 potentially pleiotropic variants for CUD severity in AI, MA, and EA respectively. Ten pleiotropic loci were shared between the cohorts although the exact variants from each cohort differed. While majority of the pleiotropic genes were distinct in each cohort, they converged on numerous enriched biological pathways. The gene ontology terms associated with the pleiotropic genes were predominately related to synaptic functions and neurodevelopment. Notable pathways included Wnt/β-catenin signaling, lipoprotein assembly, response to UV radiation, and components of the complement system. The pleiotropic genes were the most significantly differentially expressed in frontal cortex and coronary artery, up-regulated in adipose tissue, and down-regulated in testis, prostate, and ovary. They were significantly up-regulated in most brain tissues but were down-regulated in the cerebellum and hypothalamus. Our study is the first to attempt a large-scale pleiotropy detection scan for CUD severity. Our findings suggest that the different population cohorts may have distinct genetic factors for CUD, however they share pleiotropic genes from underlying pathways related to Alzheimer's disease, neuroplasticity, immune response, and reproductive endocrine systems.

Risk and mortality of testicular cancer in patients with neurodevelopmental or other psychiatric disorders

BACKGROUND

Both testicular germ cell tumours (TGCT) and neurodevelopmental disorders are associated with urogenital malformations. Few studies have investigated the association between psychiatric disorders and TGCT. We investigated whether history of any psychiatric or neurodevelopmental disorder is associated with increased risk or mortality of TGCT.

METHOD

This is a nested case-control study including 6166 TGCT patients diagnosed during 1992-2014, individually matched for age and calendar period to 61,660 controls. We calculated odds ratios (ORs) for the association between type of psychiatric diagnoses and TGCT risk. Among the cases, we used a cohort design and calculated hazard ratios (HRs) of the association between psychiatric diagnose and all-cause and TGCT-specific death.

RESULTS

History of a neurodevelopmental disorder (attention deficit hyperactivity disorder, autism spectrum disorder and intellectual disabilities) was associated with an increased risk of seminoma (OR: 1.54; 1.09-2.19). Seminoma patients with neurodevelopmental disorders were younger (34 versus 38 years, p = 0.004) and had more stage IV disease (5.4% versus 1.2%) than those without. Psychiatric history overall was not associated with TGCT. Patient history of any psychiatric disorder was associated with an increased all-cause and TGCT-specific death.

CONCLUSIONS

We report an association between neurodevelopmental disorders and testicular seminoma, and an increased TGCT-specific mortality for TGCT patients with psychiatric disorders.

Impacts of medical and non-medical cannabis on the health of older adults: Findings from a scoping review of the literature

BACKGROUND

Cannabis legalization has enabled increased consumption in older adults. Age-related mental, physical, and physiological changes may lead to differences in effects of cannabis in older adults compared to younger individuals.

OBJECTIVE

To perform a scoping review to map the evidence regarding the health effects of cannabis use for medical and non-medical purposes in older adults.

METHODS

Electronic databases (MEDLINE, Embase, PsycINFO, Cochrane Library) were searched for systematic reviews (SRs), randomized controlled trials (RCTs) and non-randomized/observational studies (NRSs) assessing the health effects and associations of cannabis use (medical or non-medical) in adults ≥ 50 years of age. Included studies met age-related inclusion criteria or involved a priori identified health conditions common among older adults. Records were screened using a liberal accelerated approach and data charting was performed independently by two reviewers. Descriptive summaries, structured tables, effect direction plots and bubble plots were used to synthesize study findings.

FINDINGS

From 31,393 citations, 133 publications describing 134 unique studies (26 SRs, 36 RCTs, 72 NRSs) were included. Medical cannabis had inconsistent therapeutic effects in specific patient conditions (e.g., end-stage cancer, dementia), with a number of studies suggesting possible benefits while others found no benefit. For medical cannabis, harmful associations outnumbered beneficial, and RCTs reported more negative effects than NRSs. Cannabis use was associated with greater frequencies of depression, anxiety, cognitive impairment, substance use and problematic substance use, accidents/injuries, and acute healthcare use. Studies often were small, did not consistently assess harms, and did not adjust for confounding.

DISCUSSION

The effects of medical cannabis are inconsistent within specific patient conditions. For older adults, generally, the available evidence suggests cannabis use may be associated with greater frequencies of mental health issues, substance use, and acute healthcare use, and the benefit-to-risk ratio is unclear. Studies with a balanced assessment of benefits and harms may guide appropriate public health messaging to balance the marketing pressures of cannabis to older adults.

Association between cannabis use with urological cancers: A population-based cohort study and a mendelian randomization study in the UK biobank

BACKGROUND

Legislation of cannabis use has been approved in many European and North American countries. Its impact on urological cancers is unclear. This study was conducted to explore the association between cannabis use and the risk of urological cancers.

METHODS

We identified 151,945 individuals with information on cannabis use in the UK Biobank from 2006 to 2010. Crude and age-standardized incidence ratios of different urological cancers were evaluated in the entire cohort and subgroups. Cox regression was performed for survival analysis.

RESULTS

Previous use of cannabis was a significant protective factor for renal cell carcinoma (HR = 0.61, 95%CI:0.40-0.93, p = 0.021) and prostate cancer (HR = 0.82, 95%CI:0.73-0.93, p = 0.002) in multivariable analysis. The association between previous cannabis use and both renal cell carcinoma and bladder cancer was only observed in females (HRRCC  = 0.42, 95%CI:0.19-0.94, p = 0.034; HRBCa  = 0.43, 95%CI:0.21-0.86, p = 0.018) but not in men. There was no significant association between cannabis use and testicular cancer incidence. Mendelian randomization demonstrated a potential causal effect of cannabis use on a lower incidence of renal cell carcinoma.

CONCLUSIONS

Previous use of cannabis was associated with a lower risk of bladder cancer, renal cell carcinoma, and prostate cancer. The inverse association between cannabis and both renal cell carcinoma and bladder cancer was only found in females but not in males.

Current Cannabidiol Safety: A Review

BACKGROUND

Marijuana, also known as cannabis, is the second most widely used illegal psychoactive substance smoked worldwide after tobacco, mainly due to the psychoactive effects induced by D-9-tetrahydrocannabinol (9-THC). Cannabidiol (CBD) is extracted from cannabis and may be used as an anti-inflammatory agent. Some patents on cannabidiol are discussed in this review. The cannabinoid is a non-psychoactive isomer of the more infamous tetrahydrocannabinol (THC); and is available in several administration modes, most known as CBD oil.

OBJECTIVES

This study aims to provide an enhanced review of cannabidiol properties used in treating inflammation. This review also emphasises the current safety profile of cannabidiol.

METHODS

Cannabis is also called Marijuana. It is the second most commonly used illegal psychoactive substance in the universe after tobacco. D-9-tetrahydrocannabinol (9-THC) present in cannabis produces psychoactive effects. Cannabidiol (CBD) extracted from cannabis is used for antiinflammatory purposes. Cannabis smoking causes various types of cancer, such as lung, tongue, and jaw. The current review took literature from Google Scholar, PubMed, and Google Patents. Many clinical investigations are included in this review.

RESULT

After analysing the literature on cannabis, it has been suggested that although cannabis is banned in some countries, it may be included in the treatment and mitigation of some diseases and symptoms like pain management, epilepsy, cancer, and anxiety disorder. Mild side effects were frequently observed in cannabis medications, which included infertility in females, liver damage, etc. Conclusion: Cannabis contains chemical compounds such as the cannabinoids delta-9- tetrahydrocannabinol (THC), a psychoactive substance, and non-psychoactive cannabidiol (CBD). Cannabidiol has been confirmed as an efficient treatment of epilepsy in several clinical trials, with one pure CBD product named Epidiolex. It is also used in treating anxiety and acne, as a pain reliever, and has anti-inflammatory properties.

Design and implementation of an Internet-Based cancer risk assessment tool: Use over 10 years

BACKGROUND

Prevention and early intervention can improve survival and quality of life across all cancers. Patient understanding of risk factors and associated actionable lifestyle changes and screening programs is not well understood by clinicians METHODS: An Internet-based tool, Reduce My Risk, was created in 2009 and made available on oncolink.org. Users voluntarily completed a survey regarding demographics and cancer risk factors, and received information about their cancer risk RESULTS: Twenty eight thousand and one surveys were completed from 2009 to 2019. Median age was 26 years (18-101); 60% were females, 87% lived in North America, and 37% had at least a bachelor's degree. Users reported on behavioral/ modifiable risk factors: 13% were current smokers, 52% were current consumers of alcohol, and 8% of those had ≥14 drinks/week. Body mass index (BMI) was ≥30 in 19%; 74% of all surveys reported dietary risks and 36% reported infrequent exercise. Excess UV exposure was reported by 19%. Among women, 36% reported performing breast self-examinations monthly, and 50% reported receiving clinician breast examinations at least once every 3 years. Sixty seven percent of men 55-75 years reported screening prostate specific antigen testing, with 50% receiving annual digital rectal examinations. Nonmodifiable risk factors included family cancer history (64%), genetic syndrome (3%), and cancer-predisposing health conditions (26%) CONCLUSIONS: Ninety-seven percent of users reported modifiable risk factors, and 60% reported ≥4 of these risk factors. Understanding detailed characteristics of a large number of respondents has the potential to improve educational interventions to reduce cancer risk through behavioral modification and cancer screening across the general public.

Marijuana and the Lung: Evolving Understandings

Human beings have used marijuana products for centuries. Relatively recent data showing extensive cannabinoid receptors, particularly in the brain, help to explain the impacts of cannabinoids on symptoms/diseases, such as pain and seizures, with major nervous system components. Marijuana can cause bronchitis, but a moderate body of literature suggests that distal airway/parenchymal lung disease does not occur; marijuana does not cause chronic obstructive pulmonary disease and probably does not cause lung cancer, distinctly different from tobacco. Potentials for cognitive impairment and for damage to the developing brain are contextually important as its beneficial uses are explored.

Cannabinoids and Their Role in Chronic Pain Treatment: Current Concepts and a Comprehensive Review

For decades, chronic pain was managed with an almost conventional approach of using a wide range of analgesic spectrum, surgical approaches and complex interventional pain techniques to modulate or even interrupt pain pathways. These different approaches carry many pharmacological hazards together with the lack of efficacy and safety of many interventional and surgical management techniques for chronic pain have mandated searching for other effective therapies including alternative treatments. Cannabinoids are naturally occurring substances that are derived from Cannabis sativa L. The usage of cannabinoids and their related synthetic chemical compounds has emerged as a choice in the management of different chronic pain conditions is being evaluated, however, the efficacy is still not consistently established. In the present investigation, therefore, we discuss the different aspects related to cannabinoids and their implications in the management of chronic pain conditions. This review will also discuss the safety profile of the cannabinoids together with the legal considerations that hinder their use in different countries.

Is psychedelic use associated with cancer?: Interrogating a half-century-old claim using contemporary population-level data

BACKGROUND

In 1967, concerns about the carcinogenic potential of psychedelics arose after a study reported chromosomal damage in human leukocytes following in vitro lysergic acid (LSD) exposure. Worries were further heightened by subsequent reports of leukemia and other cancers in LSD users. Additional investigations of psychedelics' effects on chromosomes were published over the next decade, with the majority suggesting these concerns were unfounded. However, the relationship between psychedelics and cancer has been explored only minimally from an epidemiological perspective.

AIMS

To determine whether associations exist between psychedelic use and either lifetime cancer or hematologic cancer diagnoses.

METHODS

We analyzed data from adult participants in the 2015-2019 administrations of the National Survey on Drug Use and Health for associations between lifetime use of psychedelics and lifetime diagnosis of either any cancer or hematologic cancer.

RESULTS

We identified no associations between lifetime psychedelic use and either lifetime cancer diagnosis or hematologic cancer diagnosis. Sub-analyses of lifetime lysergamide, phenethylamine, and tryptamine use also revealed no associations with lifetime cancer or hematologic cancer diagnosis.

CONCLUSIONS

While laboratory studies and case reports from the 1960s and 1970s generated concerns about psychedelics' carcinogenic potential, this analysis of recent epidemiological data does not support an association between psychedelic use and development of cancer in general or hematologic cancer. Important study limitations to consider include a lack of information about psychedelic dosage, number of lifetime psychedelic exposures, and the temporal relationship between psychedelic use and cancer diagnosis.

[Inhaled marijuana and the lung, a toxic cocktail?]

Unlike the well-documented effects of tobacco smoke on the lung, the effects of cannabis smoke remain controversial, the main bias consisting in co-consumption of tobacco. That said, the composition of joint smoke is close to that of cigarettes, containing many compounds that are carcinogenic and/or alter the respiratory epithelium. Confirmed respiratory effects in chronic cannabis smokers include aggravated chronic bronchitis symptoms, a cumulative effect with tobacco on COPD and emphysema occurrence, an increased risk of bullous emphysema, and pneumothorax with heightened risk of recurrence after pleural symphysis. Recent prospective studies have shown a negative impact on lung function, with not only damage to the airways, but also DLCO alteration and an accelerated drop in FEV1. Finally, cannabis smoking is very common among young patients with lung cancer. Its consumption could lead to a different lung cancer profile, potentially more undifferentiated and less accessible to targeted therapy. Questioning about cannabis consumption must be systematic and targeted medical care should be offered.

Endocannabinoid System and the Otolaryngologist

The endocannabinoid system is located throughout the central and peripheral nervous systems, endocrine system, gastrointestinal system, and within inflammatory cells. The use of medical cannabinoids has been gaining traction as a viable treatment option for varying illnesses in recent years. Research is ongoing looking at the effect of cannabinoids for treatment of common otolaryngologic pathologies. This article identifies common otolaryngologic pathologies where cannabinoids may have benefit, discusses potential drawbacks to cannabinoid use, and suggests future directions for research in the application of medical cannabinoids.

Perspectives of pediatric oncologists and palliative care physicians on the therapeutic use of cannabis in children with cancer

BACKGROUND

Children with cancer are increasingly using cannabis therapeutically.

AIM

The purpose of this study was to determine the perspectives and practices of pediatric oncologists and palliative care physicians regarding the use of cannabis for medical purposes among children with cancer.

METHODS

A self-administered, voluntary, cross-sectional, deidentified online survey was sent to all pediatric oncologists and palliative care physicians in Canada between June and August 2020. Survey domains included education, knowledge, and concerns about cannabis, views on its effectiveness, and the importance of cannabis-related research. Data were analyzed using descriptive statistics.

RESULTS

In total, 122/259 (47.1%) physicians completed the survey. Although 62.2% of the physicians completed some form of training about medical cannabis, nearly all (95.8%) desired to know more about the dosing, side effects, and safety of cannabis. Physicians identified a potential role of cannabis in the management of nausea and vomiting (85.7%), chronic pain (72.3%), cachexia/poor appetite (67.2%), and anxiety or depression (42.9%). Only four (0.3%) physicians recognized cannabis to be potentially useful as an anticancer agent. Nearly all physicians reported that cannabis-related research for symptom relief is essential (91.5%) in pediatric oncology, whereas 51.7% expressed that future studies are necessary to determine the anticancer effects of cannabis.

CONCLUSIONS

Our findings indicate that most pediatric oncologists and palliative care physicians recognize a potential role for cannabis in symptom control in children with cancer. Well-conducted studies are required to create evidence for cannabis use and promote shared decision making with pediatric oncology patients and their caregivers.

Global patterns in testicular cancer incidence and mortality in 2020

With 74 500 new cases worldwide in 2020, testicular cancer ranks as the 20th leading cancer type, but is the most common cancer in young men of European ancestry. While testicular cancer incidence has been rising in many populations, mortality trends, at least those in high-income settings, have been in decline since the 1970s following the introduction of platinum-based chemotherapy. To examine current incidence and mortality patterns, we extracted the new cases of, and deaths from cancers of the testis from the GLOBOCAN 2020 database. In 2020, testicular cancer was the most common cancer in men aged 15 to 44 in 62 countries worldwide. Incidence rates were highest in West-, North- and South-Europe and Oceania (age-standardised rate, ASR ≥7/100 000), followed by North America (5.6/100 000 and lowest (<2/100 000) in Asia and Africa. The mortality rates were highest in Central and South America (0.84 and 0.54 per 100 000, respectively), followed by Eastern and Southern Europe, and Western and Southern Africa. The lowest mortality rates were in Northern Europe, Northern Africa and Eastern Asia (0.16, 0.14, 0.9 per 100 000, respectively). At the country level, incidence rates varied over 100-fold, from 10/100 000 in Norway, Slovenia, Denmark and Germany to ≤0.10/100 000 in Gambia, Guinea, Liberia, Lesotho. Mortality rates were highest in Fiji, Argentina and Mexico. Our results indicate a higher mortality burden in countries undergoing economic transitions and reinforce the need for more equitable access to testicular cancer diagnosis and treatment globally.

Modification of Behavioral Habits in Prehabilitation Programs

OBJECTIVES

To review the evidence supporting the modification of behavioral habits and substance use management during cancer treatment and how to implement them as part of a multimodal optimization intervention.

DATA SOURCES

A literature review of the association between cancer and behavioral habits, their impact on oncological treatment outcomes, and substance use management guidelines.

CONCLUSION

There is an association between harmful habits, such as smoking and alcohol consumption, and cancer. The continuation of poor behavioral habits throughout oncological treatments is associated with poor oncological outcomes and increased complications. Prehabilitation could be an ideal setting to screen, assess, and modify these harmful habits. Prehabilitation programs should be equipped with professionals and resources to help patients achieve harmful habit cessation.

IMPLICATIONS FOR NURSING PRACTICE

This review puts into manifest the importance of a multidisciplinary approach to substance use management. It can serve as a framework to develop a harmful habit cessation intervention in the context of multimodal prehabilitation to improve surgical and oncological outcomes in the cancer population.

A cross-sectional survey: Exploring future healthcare workers' intention to use cannabis through extended theory of planned behavior

Cannabis is the most extensively abused drug, leading to multiple health burdens such as traffic accidents and psychosis. There is a global wave of legalization of recreational and medical cannabis. This study aimed to understand future healthcare workers' intention to use cannabis through extended Theory of Planned Behavior (TPB). An online cross-sectional survey on cannabis, including validated survey tools and questions on demographics, knowledge, and constructs of the TPB was designed, and distributed during virtual classes in late 2020. Responses were obtained from the Faculty of Medicine of a local university. Nine hundred ninety-six responses were collected, of which 629 were complete and analysed. Age was the only demographic variable associated with cannabis use intention (p = 0.029). Respondents with intention had better knowledge of cannabis. All TPB and additional constructs, including perceived behavioral control (COR = 3.44, 95% CI 2.72-4.35, p < 0.001), descriptive norm (COR = 2.24, 95% CI 1.81-2.77, p < 0.001), injunctive norm (COR = 0.51, 95% CI 0.42-0.61, p < 0.001), attitude (COR = 1.23, 95% CI 1.18-1.28, p < 0.001), knowledge (COR = 1.08, 95% CI 1.03-1.14), and perceived availability (COR = 2.75, 95% CI 2.22-3.40, p < 0.001) were individually associated with intention. In the final multiple logistic regression model adjusted for age, only attitude (AOR = 1.19, 95% CI 1.13-1.25, p < 0.001) and perceived availability (p = 0.004) showed statistically significant associations with intention. Descriptive norm (standardized coefficient = 0.570) had better explanatory power than the injunctive norm (standardized coefficient = -0.143) in the model. Perceived behavioral control was associated with intention among respondents with negative to neutral attitudes towards cannabis (AOR = 2.48, 95% CI 1.63-3.77, p < 0.001), but not among those with positive attitudes. All TPB constructs positively correlated with the intention to use cannabis. Changing the attitudes and perceived control on cannabis use may be useful in preventing cannabis use.

Cannabinoids orchestrate cross-talk between cancer cells and endothelial cells in colorectal cancer

Medical marijuana has been approved by the FDA for treating chemotherapy-induced nausea and vomiting. However, less is known about its direct effects on tumor cells and the tumor microenvironment. In this study, RNA-sequencing datasets in the NCBI GEO repository were first analyzed; upregulation of cannabinoid receptors was observed in both primary and metastatic colorectal cancer (CRC) tumor tissues. An increase of cannabinoid receptors was also found in patients with CRC, azoxymethane/dextran sulfate sodium-induced CRC and CRC metastatic mouse models. Δ⁹-Tetrahydrocannabinol (Δ⁹-THC)-induced tumor progression in both primary and metastatic mouse models and also increased angiogenesis. A human growth factor antibody array indicated that Δ⁹-THC promoted the secretion of angiogenic growth factors in CRC, leading to the induction of tube formation and migration in human-induced pluripotent stem cell-derived vascular endothelial cells. The nuclear translocation of STAT1 played important roles in Δ⁹-THC-induced angiogenesis and tumor progression. Pharmacological treatment with STAT1 antagonist or abrogation of STAT1 with CRISPR/Cas9-based strategy rescued those effects of Δ⁹-THC in CRC. This study demonstrates that marijuana might increase the risk of CRC progression and that inhibition of STAT1 is a potential strategy for attenuating these side effects.

Impact of Cannabinoid Compounds on Skin Cancer

Drugs targeting the endocannabinoid system are of interest as potential systemic chemotherapeutic treatments and for palliative care in cancer. In this context, cannabinoid compounds have been successfully tested as a systemic therapeutic option in preclinical models over the past decades. Recent findings have suggested an essential function of the endocannabinoid system in the homeostasis of various skin functions and indicated that cannabinoids could also be considered for the treatment and prophylaxis of tumour diseases of the skin. Cannabinoids have been shown to exert their anticarcinogenic effects at different levels of skin cancer progression, such as inhibition of tumour growth, proliferation, invasion and angiogenesis, as well as inducing apoptosis and autophagy. This review provides an insight into the current literature on cannabinoid compounds as potential pharmaceuticals for the treatment of melanoma and squamous cell carcinoma.

Geotemporospatial and causal inferential epidemiological overview and survey of USA cannabis, cannabidiol and cannabinoid genotoxicity expressed in cancer incidence 2003-2017: part 1 - continuous bivariate analysis

BACKGROUND

The genotoxic and cancerogenic impacts of population-wide cannabinoid exposure remains an open but highly salient question. The present report examines these issues from a continuous bivariate perspective with subsequent reports continuing categorical and detailed analyses.

METHODS

Age-standardized state census incidence of 28 cancer types (including "All (non-skin) Cancer") was sourced using SEER*Stat software from Centres for Disease Control and National Cancer Institute across US states 2001-2017. It was joined with drug exposure data from the nationally representative National Survey of Drug Use and Health conducted annually by the Substance Abuse and Mental Health Services Administration 2003-2017, response rate 74.1%. Cannabinoid data was from Federal seizure data. Income and ethnicity data sourced from the US Census Bureau. Data was processed in R.

RESULTS

Nineteen thousand eight hundred seventy-seven age-standardized cancer rates were returned. Based on these rates and state populations this equated to 51,623,922 cancer cases over an aggregated population 2003-2017 of 124,896,418,350. Regression lines were charted for cancer-substance exposures for cigarettes, alcohol use disorder (AUD), cannabis, THC, cannabidiol, cannabichromene, cannabinol and cannabigerol. In this substance series positive trends were found for 14, 9, 6, 9, 12, 6, 9 and 7 cancers; with largest minimum E-Values (mEV) of 1.76 × 109, 4.67 × 108, 2.74 × 104, 4.72, 2.34 × 1018, 2.74 × 1017, 1.90 × 107, 5.05 × 109; and total sum of exponents of mEV of 34, 32, 13, 0, 103, 58, 25, 31 indicating that cannabidiol followed by cannabichromene are the most strongly implicated in environmental carcinogenesis. Breast cancer was associated with tobacco and all cannabinoids (from mEV = 3.53 × 109); "All Cancer" (non-skin) linked with cannabidiol (mEV = 1.43 × 1011); pediatric AML linked with cannabis (mEV = 19.61); testicular cancer linked with THC (mEV = 1.33). Cancers demonstrating elevated mEV in association with THC were: thyroid, liver, pancreas, AML, breast, oropharynx, CML, testis and kidney. Cancers demonstrating elevated mEV in relation to cannabidiol: prostate, bladder, ovary, all cancers, colorectum, Hodgkins, brain, Non-Hodgkins lymphoma, esophagus, breast and stomach.

CONCLUSION

Data suggest that cannabinoids including THC and cannabidiol are important community carcinogens exceeding the effects of tobacco or alcohol. Testicular, (prostatic) and ovarian tumours indicate mutagenic corruption of the germline in both sexes; pediatric tumourigenesis confirms transgenerational oncogenesis; quantitative criteria implying causality are fulfilled.

Geotemporospatial and causal inferential epidemiological overview and survey of USA cannabis, cannabidiol and cannabinoid genotoxicity expressed in cancer incidence 2003-2017: part 3 - spatiotemporal, multivariable and causal inferential pathfinding and exploratory analyses of prostate and ovarian cancers

BACKGROUND

The epidemiology of cannabinoid-related cancerogenesis has not been studied with cutting edge epidemiological techniques. Building on earlier bivariate papers in this series we aimed to conduct pathfinding studies to address this gap in two tumours of the reproductive tract, prostate and ovarian cancer.

METHODS

Age-standardized cancer incidence data for 28 tumour types (including "All (non-skin) Cancer") was sourced from Centres for Disease Control and National Cancer Institute using SEER*Stat software across US states 2001-2017. Drug exposure was sourced from the nationally representative household survey National Survey of Drug Use and Health conducted annually by the Substance Abuse and Mental Health Services Administration 2003-2017 with response rate 74.1%. Federal seizure data provided cannabinoid concentration data. US Census Bureau provided income and ethnicity data. Inverse probability weighted mixed effects, robust and panel regression together with geospatiotemporal regression analyses were conducted in R. E-Values were also calculated.

RESULTS

19,877 age-standardized cancer rates were returned. Based on these rates and state populations this equated to 51,623,922 cancer cases over an aggregated population 2003-2017 of 124,896,418,350. Inverse probability weighted regressions for prostate and ovarian cancers confirmed causal associations robust to adjustment. Cannabidiol alone was significantly associated with prostate cancer (β-estimate = 1.61, (95%C.I. 0.99, 2.23), P = 3.75 × 10- 7). In a fully adjusted geospatiotemporal model at one spatial and two temporal years lags cannabidiol was significantly independently associated with prostate cancer (β-estimate = 2.08, (1.19, 2.98), P = 5.20 × 10- 6). Cannabidiol alone was positively associated with ovarian cancer incidence in a geospatiotemporal model (β-estimate = 0.36, (0.30, 0.42), P <  2.20 × 10- 16). The cigarette: THC: cannabidiol interaction was significant in a fully adjusted geospatiotemporal model at six years of temporal lag (β-estimate = 1.93, (1.07, 2.78), P = 9.96 × 10- 6). Minimal modelled polynomial E-Values for prostate and ovarian cancer ranged up to 5.59 × 1059 and 1.92 × 10125. Geotemporospatial modelling of these tumours showed that the cannabidiol-carcinogenesis relationship was supra-linear and highly sigmoidal (P = 1.25 × 10- 45 and 12.82 × 10- 52 for linear v. polynomial models).

CONCLUSION

Cannabinoids including THC and cannabidiol are therefore important community carcinogens additive to the effects of tobacco and greatly exceeding those of alcohol. Reproductive tract carcinogenesis necessarily implies genotoxicity and epigenotoxicity of the germ line with transgenerational potential. Pseudoexponential and causal dose-response power functions are demonstrated.

Geospatiotemporal and causal inference study of cannabis and other drugs as risk factors for female breast cancer USA 2003-2017

Breast cancer (BC) is the commonest human cancer and its incidence (BC incidence, BCI) is rising worldwide. Whilst both tobacco and alcohol have been linked to BCI genotoxic cannabinoids have not been investigated. Age-adjusted state-based BCI 2003-2017 was taken from the Surveillance Epidemiology and End Results database of the Centers for Disease Control. Drug use from the National Survey of Drug Use and Health, response rate 74.1%. Median age, median household income and ethnicity were from US census. Inverse probability weighted (ipw) multivariable regression conducted in R. In bivariate analysis BCI was shown to be significantly linked with rising cannabis exposure {β-est. = 3.93 [95% confidence interval 2.99, 4.87], P = 1.10 × 10-15}. At 8 years lag cigarettes:cannabis [β-est. = 2660 (2150.4, 3169.3), P = 4.60 × 10-22] and cannabis:alcoholism [β-est. = 7010 (5461.6, 8558.4), P = 1.80 × 10-17] were significant in ipw-panel regression. Terms including cannabidiol [CBD; β-est. = 16.16 (0.39, 31.93), P = 0.446] and cannabigerol [CBG; β-est. = 6.23 (2.06, 10.39), P = 0.0034] were significant in spatiotemporal models lagged 1:2 years, respectively. Cannabis-liberal paradigms had higher BCI [67.50 ± 0.26 v. 65.19 ± 0.21/100 000 (mean ± SEM), P = 1.87 × 10-11; β-est. = 2.31 (1.65, 2.96), P = 9.09 × 10-12]. 55/58 expected values >1.25 and 13/58 >100. Abortion was independently and causally significant in space-time models. Data show that exposure to cannabis and the cannabinoids Δ9-tetrahydrocannabinol, CBD, CBG and alcoholism fulfil quantitative causal criteria for BCI across space and time. Findings are robust to adjustment for age and several known sociodemographic, socio-economic and hormonal risk factors and establish cannabinoids as an additional risk factor class for breast carcinogenesis. BCI is higher under cannabis-liberal legal paradigms.

Cannabis, Cannabinoids and Cannabis-Based Medicines in Cancer Care

As medical cannabis becomes legal in more states, cancer patients are increasingly interested in the potential utility of the ancient botanical in their treatment regimen. Although eager to discuss cannabis use with their oncologist, patients often find that their provider reports that they do not have adequate information to be helpful. Oncologists, so dependent on evidence-based data to guide their treatment plans, are dismayed by the lack of published literature on the benefits of medical cannabis. This results largely from the significant barriers that have existed to effectively thwart the ability to conduct trials investigating the potential therapeutic efficacy of the plant. This is a narrative review aimed at clinicians, summarizing cannabis phytochemistry, trials in the areas of nausea and vomiting, appetite, pain and anticancer activity, including assessment of case reports of antitumor use, with reflective assessments of the quality and quantity of evidence. Despite preclinical evidence and social media claims, the utility of cannabis, cannabinoids or cannabis-based medicines in the treatment of cancer remains to be convincingly demonstrated. With an acceptable safety profile, cannabis and its congeners may be useful in managing symptoms related to cancer or its treatment. Further clinical trials should be conducted to evaluate whether the preclinical antitumor effects translate into benefit for cancer patients. Oncologists should familiarize themselves with the available database to be able to better advise their patients on the potential uses of this complementary botanical therapy.

The Effects of Cannabinoids on Sleep

The use of cannabis products to help with sleep and various other medical conditions by the public has increased significantly in recent years. Withdrawal from cannabinoids can lead to sleep disturbance. Here, we describe a patient who developed significant insomnia leading to worsening anxiety, mood, and suicidal ideation in the setting of medical cannabis withdrawal, prompting presentation to the Emergency Department and inpatient admission. There is a limited evidence base for the use of cannabis products for sleep. We provide a comprehensive review evaluating the literature on the use of cannabis products on sleep, including an overview of cannabis and related psychoactive compounds, the current state of the law as it pertains to the prescribing and use of these substances, and potential side effects and drug interactions. We specifically discuss the impact of cannabis products on normal sleep and circadian sleep-wake rhythms, insomnia, excessive daytime sleepiness, sleep apnea, parasomnias, and restless legs syndrome. We also describe the effects of cannabis withdrawal on sleep and how this increases relapse to cannabis use. Most of the studies are observational but the few published randomized controlled trials are reviewed. Our comprehensive review of the effects of cannabis products on normal sleep and sleep disorders, relevant to primary care providers and other clinicians evaluating and treating patients who use these types of products, shows that cannabis products have minimal to no effects on sleep disorders and may have deleterious effects in some individuals. Further research examining the differential impact of the various types of cannabinoids that are currently available on each of these sleep disorders is required.

Mortality in substance-induced psychosis: a register-based national cohort study

AIMS

We aimed to analyze whether people with substance-induced psychosis (SIP), both those who convert and do not convert to schizophrenia, have higher all-cause and cause-specific mortality when compared to the general population.

DESIGN

Prospective cohort study.

SETTING

Nationwide Danish registers.

PARTICIPANTS/CASES

We included all people born in Denmark, living in Denmark on their 15th birthday, and age 15 or more during the study period from January 1, 1994, and August 10, 2017.

MEASUREMENTS

Exposure was categorized as: (i) neither SIP nor schizophrenia; (ii) SIP without preceding schizophrenia; (iii) SIP converted to schizophrenia; and (iv) schizophrenia without preceding SIP. Any SIP and substance-specific SIPS were examined regarding all-cause and cause-specific mortality.

FINDINGS

The study included a total of 5 619 691 individuals. Compared to people with neither schizophrenia nor SIP, people with SIP without preceding schizophrenia had an increased risk of dying (hazard ratio [HR] = 6.23, 95% CI = 5.96-6.50), as had those with SIP converting to schizophrenia (HR = 9.77, 95% CI = 8.84-10.79) and those with only schizophrenia (HR = 3.07, 95% CI = 3.03-3.13). A similar pattern, albeit with higher HRs, was observed for suicides and accidental deaths. Other cause-specific-mortality groups also generally showed the same pattern, as did types of individual substances.

CONCLUSIONS

Substance-induced psychosis was strongly associated with an increased risk of both all-cause and cause-specific mortality, even among cases who did not convert to schizophrenia. This provides a strong rationale for monitoring people with previous diagnosis of substance-induced psychosis and developing and implementing interventions to reduce this excess mortality.

Public health monitoring of cannabis use in Europe: prevalence of use, cannabis potency, and treatment rates

Background

Cannabis is one of the most widely used substances worldwide. Heavy use is associated with an increased risk of cannabis use disorders, psychotic disorders, acute cognitive impairment, traffic injuries, respiratory problems, worse pregnancy outcomes, and there are indications for genotoxic and epigenotoxic adverse effects. International regulation of medical and non-medical cannabis use is changing rapidly and substantially, highlighting the importance of robust public health monitoring. This study aimed to describe the trends of key public health indicators in European Union (27 member states + UK, Norway and Turkey) for the period 2010 to 2019, their public health implications, and to identify the steps required to improve current practice in monitoring of cannabis use and harm in Europe.

Methods

Data on four key cannabis indicators (prevalence of use, prevalence of cannabis use disorder [CUD], treatment rates, and potency of cannabis products) in Europe were extracted from the United Nations Office on Drugs and Crime, European Monitoring Centre for Drugs and Drug Addiction and the Global Burden of Disease study. For prevalence of use and CUD, the first and last available estimate in each country were compared. For treatment rates and cannabis potency, linear regression models were conducted.

Findings

Between 2010 and 2019, past-month prevalence of cannabis use increased by 27% in European adults (from 3·1 to 3·9%), with most pronounced relative increases observed among 35-64 year-olds. In 13 out of 26 countries, over 20% of all past-month users reported high-risk use patterns. The rate of treatment entry for cannabis problems per 100,000 adults increased from 27·0 (95% CI: 17·2 to 36·8) to 35·1 (95% CI: 23·6 to 46·7) and has mostly plateaued since 2015. Modest increases in potency were found in herbal cannabis (from 6·9% to 10·6% THC) while median THC values tripled in cannabis resin (from 7·6% to 24·1% THC).

Interpretation

In the past decade, cannabis use, treatment rates and potency levels have increased in Europe highlighting major concerns about the public health impact of cannabis use. Continued monitoring and efforts to improve data quality and reporting, including indicators of high-risk use and cannabis-attributable harm, will be necessary to evaluate the health impact of international changes in cannabis regulation.

Funding

This study received no specific funding.

Medical Cannabis as Adjunctive Therapy for Head and Neck Cancer Patients

The goal of this systematic review was to define a consensus within the current literature regarding the impact/effect of cannabis or cannabinoids on the treatment of patients with head and neck cancer. We conducted a review of PubMed, Embase, and Web of Science databases, using a comprehensive search strategy, focusing on articles relating to head & neck cancer and cannabis/cannabinoids without a time limit for publication.

Two, independent reviewers screened articles based on title/abstract and included the ones selected by both. We then conducted a full-text review and excluded all articles which did not meet inclusion criteria. A single reviewer then assessed studies for methodological quality and extracted relevant data using a premade data collection tool. We identified five studies that met inclusion criteria. Studies were of varying quality and the majority investigated recreational cannabis use with only one study reporting dosing across participants. Lack of standardized cannabis exposure presents a wide array of potential confounding variables across the remaining studies. Meta-analysis was not attempted due to variability in reported outcomes.

It is impossible to draw any conclusions regarding the benefit or adverse effects of current medical cannabis products in this patient population. The literature regarding the effect of cannabis/cannabinoids on head & neck cancer patients is limited. However, the current lack of evidence does not definitively disprove the efficacy of cannabis. High-quality studies are necessary for physicians to provide advice to patients who are either using or interested in cannabis as an adjunctive treatment.

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.

Illicit drug use and oral health

People with drug use disorders (PWDUD) have elevated prevalence of oral diseases, in particular dental caries (tooth decay), periodontal (gum) disease and xerostomia (dry mouth). When left untreated, these oral health conditions may progress and lead to tooth ache, abscesses and tooth loss, and in turn, to poor chewing functioning and digestion, dental aesthetic problems and reduced wellbeing. Illicit drug use may, per se, cause xerostomia, which in turn increases vulnerability for dental caries. However, the other main drivers of oral diseases and their progression-poor oral hygiene, frequent sugar intake and infrequent dental visits-can mainly be ascribed to the irregular lifestyle, poor economy and mental health problems that often accompany illicit drug use. Establishment of good oral health habits is essential in the dental care for PWDUD. Dental treatment is often comprehensive and challenging; because the patients may have extensive treatment needs but also difficulties adhering to preventive measures and dental appointments. An integrated care approach for PWDUD would likely benefit both their oral and general health.