An epidemiologic review of marijuana and cancer: an update

Distal and Proximal Minority Stressors on Patterns of Tobacco and Cannabis Use Among Young Bisexual Women

BACKGROUND

Bisexual women have high rates of tobacco and cannabis use, but few studies have examined co-use behavior in this population. Although the role of distal minority stressors (eg, discrimination) on substance use has been examined, fewer studies have examined proximal minority stressors (eg, negative sexual identity self-schemas). The current study was a secondary data analysis that examined patterns of tobacco and cannabis use, and the role of distal (instability of bisexuality, sexual irresponsibility of bisexual people, and hostility toward bisexual people) and proximal (illegitimacy of bisexuality, anticipated binegativity, internalized binegativity, and identity affirmation) bisexual-specific minority stressors among bisexual women.

METHODS

Participants were 224 young (aged 18-30 years old) self-identified bisexual women who reported on their past 30-day tobacco and cannabis use and completed measures of distal and proximal bisexual-specific minority stressors. Participants were categorized into one of 4 patterns: no use, tobacco use only, cannabis use only, and tobacco and cannabis co-use.

RESULTS

The most common pattern of past 30-day use was tobacco and cannabis co-use (39.1%). Results from a multinomial logistic regression revealed that bisexual women who reported higher illegitimacy of bisexuality, a proximal minority stressor, were significantly more likely to engage in tobacco and cannabis co-use, relative to no use.

DISCUSSION

Bisexual women have particularly high rates of substance use, with tobacco and cannabis co-use as the most common pattern. Incorporating the role of proximal minority stressors, and specifically, beliefs about the legitimacy of bisexuality, may be an important target of substance use interventions for bisexual women.

Cannabis Unveiled: An Exploration of Marijuana's History, Active Compounds, Effects, Benefits, and Risks on Human Health

Marijuana, also known as cannabis, is a psychoactive drug that comes from the Cannabis plant. Marijuana can be smoked, vaporized, or consumed through edibles in a variety of ways. Perception changes, changes in mood, and problems with coordination are all possible side effects. Marijuana is used for both recreational and medical purposes to treat a variety of health conditions. The literature review on the effects of marijuana on the human body has increased in recent years as more states legalize its use. It is important to investigate the benefits and harmful effects of marijuana on individuals due to the widespread use of cannabis-derived substances like marijuana for medical, recreational, and combined purposes. The paper will review different aspects of marijuana in 4 main domains. A thorough discussion of marijuana's definition, history, mechanism of action, pharmacokinetics, and effects on human cells will be given in the first domain. The second domain will concentrate on marijuana's negative effects, while the third domain will look at marijuana's possible positive impacts, such as its usage in controlling multiple sclerosis, treating obesity, lowering social anxiety, and managing pain. The fourth domain will concentrate on marijuana's effects on anxiety, educational attainment, and social consequences. Additionally, this paper also will provide a highlight of the history of marijuana use and governmental legislation, both of which play a significant role in determining how the public views marijuana. In conclusion, this paper provides a comprehensive review of marijuana's effects, which may be of interest to a large readership. This review adds to the continuing discussion about the use of marijuana by analyzing the data that is currently available about the possible advantages and disadvantages of marijuana usage.

Increasing Cancer in Adolescents and Young Adults: Cancer Types and Causation Implications

Purpose: This study aimed to identify cancer incidence trends in the United States and globally in adolescents and young adults (AYAs) 15-39 years of age, by sex, and to speculate on causes for trend changes. Methods: For the United States, SEER*Stat was used to obtain average annual percent change (AAPC) trends in cancer incidence during the period 2000-2019 among 395,163 AYAs. For global data, the source was the Institute of Health Metrics and Evaluation and its sociodemographic index (SDI) classification system. Results: In the United States, the invasive cancer incidence increased during the period 2000-2019 in both females (AAPC: 1.05, 95% CI: 0.90-1.20, p << 0.001) and males (AAPC: 0.56, 95% CI: 0.43-0.69, p << 0.001). A total of 25 and 20 types of cancers increased statistically significantly in female and male AYAs, respectively. Among potential causes for the increases, the obesity epidemic in the United States strongly correlates with the overall cancer increase in both its female (Pearson correlation coefficient R2 = 0.88, p = 0.0007) and male (R2 = 0.83, p = 0.003) AYAs, as does the most common malignancy in American AYAs, breast cancer (R2 = 0.83, p = 0.003). Worldwide, cancer incidence in the age group increased steadily during the period 2000-2019 among high-middle, middle, and low-middle SDI countries, but not in low SDI countries and with slowing of increase in high SDI countries. Conclusions: The increases and their age-dependent profiles implicate several causations that are preventable, including obesity, overdiagnosis, unnecessary diagnostic radiation, human papilloma virus infection, and cannabis avoidance. The United States is beginning to reverse the increasing incidence, and prevention efforts should be augmented accordingly.

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.

Protective Behavioural Mechanisms Against Cannabis Use Among Adolescents in Cannabis-Growing Settings of South Africa: Insights Into Adolescent Cannabis Use Prevention

We aimed to explore the behavioural protective mechanisms against cannabis use among adolescents living in South African illicit cannabis-growing communities, based on the Self Determination Theory (SDT). Exploratory qualitative design techniques were followed in conducting the study. The snowball sampling technique was used to recruit thirty (30) non-cannabis smoking adolescents from 2 purposively selected communities and grouped into 4 focus groups and interviewed. A semi-structured focus group interview guide was used to moderate the discussions. Data were analysed inductively, using the ATLAS. ti software. Nine behavioural coping mechanisms, grouped under intrinsic and extrinsic protective behavioural mechanisms, protected participants from using cannabis. Intrinsically, participants' determination not to engage in bad behaviours, focus on their academic work during their free periods, their non-financial dependence on cannabis-using peers, self-preservation to ensure good marriages, and religious beliefs on substance abuse motivated them to not use cannabis. On the other hand, the concept of Ukuphoxa (preservation of family dignity), fear of arrest, fear of being tagged a social deviant, and the fear of contracting illnesses such as lung cancer served as protective behavioural mechanisms against cannabis use. Health promotion and education programmes for adolescents on non-cannabis use in communities where illicit cannabis abounds must identify and draw on contextual intrinsic and extrinsic motivations that ensure non-cannabis use.

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.

Genotoxicity of Marijuana in Mono-Users

Marijuana (Cannabis sp.) is among the most recurred controlled substances in the world, and there is a growing tendency to legalize its possession and use; however, the genotoxic effects of marijuana remain under debate. A clear definition of marijuana's genotoxic effects remains obscure by the simultaneous consumption of tobacco and other recreational substances. In order to assess the genotoxic effects of marijuana and to prevent the bias caused by the use of substances other than cannabis, we recruited marijuana users that were sub-divided into three categories: (1) users of marijuana-only (M), (2) users of marijuana and tobacco (M+T), and (3) users of marijuana plus other recreative substances or illicit drugs (M+O), all the groups were compared against a non-user control group. We quantified DNA damage by detection of γH2AX levels and quantification of micronuclei (MN), one of the best-established methods for measuring chromosomal DNA damage. We found increased levels of γH2AX in peripheral blood lymphocytes from the M and M+T groups, and increased levels of MNs in cultures from M+T group. Our results suggest a DNA damage increment for M and M+T groups but the extent of chromosomal damage (revealed here by the presence of MNs and NBuds) might be related to the compounds found in tobacco. We also observed an elevated nuclear division index in all marijuana users in comparison to the control group suggesting a cytostatic dysregulation caused by cannabis use. Our study is the first in Mexico to assess the genotoxicity of marijuana in mono-users and in combination with other illicit drugs.

Wonder or evil?: Multifaceted health hazards and health benefits of Cannabis sativa and its phytochemicals

Cannabis sativa, widely known as 'Marijuana' poses a dilemma for being a blend of both good and bad medicinal effects. The historical use of Cannabis for both medicinal and recreational purposes suggests it to be a friendly plant. However, whether the misuse of Cannabis and the cannabinoids derived from it can hamper normal body physiology is a focus of ongoing research. On the one hand, there is enough evidence to suggest that misuse of marijuana can cause deleterious effects on various organs like the lungs, immune system, cardiovascular system, etc. and also influence fertility and cause teratogenic effects. However, on the other hand, marijuana has been found to offer a magical cure for anorexia, chronic pain, muscle spasticity, nausea, and disturbed sleep. Indeed, most recently, the United Nations has given its verdict in favour of Cannabis declaring it as a non-dangerous narcotic. This review provides insights into the various health effects of Cannabis and its specialized metabolites and indicates how wise steps can be taken to promote good use and prevent misuse of the metabolites derived from this plant.

Nonmedical Cannabis Use: Patterns and Correlates of Use, Exposure, and Harm, and Cancer Risk

Cannabis has certain health benefits, but some people may experience harms from use. Co-use of tobacco and cannabis is common. Smoke from cannabis contains many of the same carcinogens and toxicants as the smoke from tobacco, raising concerns that cannabis smoking may be a risk factor for cancer. With growing access to and acceptance of medical and nonmedical cannabis, there is an urgent need to understand the risks and benefits of the current modes of cannabis use and how cannabis may be associated with cancer risk. This monograph summarizes a session from a National Cancer Institute Symposium on nonmedical cannabis use and cancer risk. We had 3 objectives: describe the relation between nonmedical cannabis use and cancer risk, delineate patterns and correlates of cannabis co-use with tobacco, and document potentially harmful inhalational exposure resulting from smoked and vaped cannabis. Methodological limitations in the literature and future research recommendations are provided.

How marijuana use status affects responses to anti-marijuana messages

Background

The current study examined how cannabis use status impacts cognitive and emotional reactions to public health campaigns about cannabis, and the degree to which these reactions influence message likeability and attitudes about cannabis-related harms.

Methods

In a between-subjects design, 252 subjects recruited via Amazon Mechanical Turk viewed six real-world cannabis education messages: three message themes (cognitive ability, driving, and health harms) from each of two real-world public campaigns. Subjects answered questions measuring their cognitive and emotional reactions to each message as well as message likeability and harm perceptions of cannabis. Analyses examined the mediating effects of message responsiveness on the association between baseline cannabis use (user vs non-user) with indices of liking and harm.

Results

For all three message themes, informativeness ratings mediated the effect of cannabis user status on the outcomes of perceived harmfulness and message likeability. Specifically, cannabis users perceived cannabis as less harmful and reported all messages as less likeable compared to non-users, partly because they perceived the messages to be less informative than non-users. Surprisingly, users found some of the messages to be more pleasant, which was associated with increased perceptions of harm and message liking compared to non-users.

Conclusions

Cannabis education campaigns that take into account differences in emotional and cognitive reactions by use experience, rather than use a "one size fits all" approach, could possibly maximally impact likeability and harm perceptions of these messages.

Cognitive and affective responses to marijuana prevention and educational messaging

BACKGROUND

Perceptions of risk of using marijuana have decreased significantly in the US over the last decade, while marijuana use has increased. In order to educate people on the risks associated with marijuana use, large-scale health messaging campaigns have been deployed to educate the public about the risks associated with marijuana use, particularly in states where medical or recreational marijuana is legal. Few studies have examined how messages about marijuana affect the audiences' cognitive and emotional responsivity to these messages.

METHODS

To address this knowledge gap, this study used psychophysiological assessment (heart rate, skin conductance, facial action coding) and self-report measures to explore the impact of different marijuana risk messages on real-time cognitive and affective responses and self-reported message receptivity, likeability, and intentions to use marijuana in a sample of 50 young adult marijuana users and non-users. Each participant saw six messages. Three messages were used from each of two campaigns, representing one of three risks (cognitive ability, driving, health harms).

RESULTS

Psychophysiological responses showed that the driving-themed messages for both campaigns had the greatest cognitive resource allocation to encoding the message, the greatest arousal, and the most positive emotional response, regardless of user status. Self-reports showed a less consistent pattern.

CONCLUSIONS

Overall, psychophysiological measures provided a more consistent picture of message processing and effects than self-report measures. Findings from this study provide immediately useful data for improving the development and effectiveness of marijuana health-risk prevention campaigns by elucidating cognitive and emotional processes that could be targeted in future programs.

General risks of harm with cannabinoids, cannabis, and cannabis-based medicine possibly relevant to patients receiving these for pain management: an overview of systematic reviews

ABSTRACT

The growing demand for improved pain treatments together with expanding legalization of, and access to, cannabinoids, cannabis, and cannabis-based medicines has intensified the focus on risk-benefit considerations in pain management. Given limited harms data from analgesic clinical trials, we conducted an overview of systematic reviews focused on all harms possibly relevant to patients receiving cannabinoids for pain management. This PROSPERO-registered, PRISMA-compliant systematic overview identified 79 reviews, encompassing over 2200 individual reports about psychiatric and psychosocial harms, cognitive/behavioral effects, motor vehicle accidents, cardiovascular, respiratory, cancer-related, maternal/fetal, and general harms. Reviews, and their included studies, were of variable quality. Available evidence suggests variable associations between cannabis exposure (ranging from monthly to daily use based largely on self-report) and psychosis, motor vehicle accidents, respiratory problems, and other harms. Most evidence comes from settings other than that of pain management (eg, nonmedicinal and experimental) but does signal a need for caution and more robust harms evaluation in future studies. Given partial overlap between patients receiving cannabinoids for pain management and individuals using cannabinoids for other reasons, lessons from the crisis of oversupply and overuse of opioids in some parts of the world emphasize the need to broadly consider harms evidence from real-world settings. The advancement of research on cannabinoid harms will serve to guide optimal approaches to the use of cannabinoids for pain management. In the meantime, this evidence should be carefully examined when making risk-benefit considerations about the use of cannabinoids, cannabis, and cannabis-based medicine for chronic pain.

Cannabis Significantly Reduces the Use of Prescription Opioids and Improves Quality of Life in Authorized Patients: Results of a Large Prospective Study

OBJECTIVES

This article presents findings from a large prospective examination of Canadian medical cannabis patients, with a focus on the impacts of cannabis on prescription opioid use and quality of life over a 6-month period.

METHODS

The Tilray Observational Patient Study took place at 21 medical clinics throughout Canada. This analysis includes 1,145 patients who had at least one postbaseline visit, with follow-up at 1, 3, and 6 months. Instruments included a comprehensive cannabis use inventory, the World Health Organization Quality of Life Short Form (WHOQOL-BREF), and a detailed prescription drug questionnaire.

RESULTS

Participants were 57.6% female, with a median age of 52 years. Baseline opioid use was reported by 28% of participants, dropping to 11% at 6 months. Daily opioid use went from 152 mg morphine milligram equivalent (MME) at baseline to 32.2 mg MME at 6 months, a 78% reduction in mean opioid dosage. Similar reductions were also seen in the other four primary prescription drug classes identified by participants, and statistically significant improvements were reported in all four domains of the WHOQOL-BREF.

CONCLUSIONS

This study provides an individual-level perspective of cannabis substitution for opioids and other prescription drugs, as well as associated improvement in quality of life over 6 months. The high rate of cannabis use for chronic pain and the subsequent reductions in opioid use suggest that cannabis may play a harm reduction role in the opioid overdose crisis, potentially improving the quality of life of patients and overall public health.

Scoping Review and Meta-Analysis Suggests that Cannabis Use May Reduce Cancer Risk in the United States

Introduction: Cannabis smoke contains carcinogens similar to tobacco, in addition to compounds with antitumor activity. Cannabis use reduces the risk of obesity and cannabinoids inhibit chronic inflammation, known causes of cancer. The net effect of Cannabis use on cancer risk is not known. Objective: To examine the association between Cannabis use and cancer risk in the United States. Methods: Identify and analyze published data on cancer risk in Cannabis users. Results: A total of 55 data points, consisting of risk ratios of cancer in Cannabis users and nonusers, were identified from 34 studies. Of these, 5 did not contain data essential for inclusion in the meta-analysis. The remaining data showed a nonsignificant trend to an association with reduced risk (relative risk [RR]=0.90, p>0.06, N=50) although heterogeneity is high (I²=72.4%). Removal of data with high risk of selection bias (defined as those from North Africa and those that failed to adjust for tobacco) and data with high risk of performance bias (defined as those with fewer than 20 cases or controls among Cannabis users) resulted in an RR <1.0 (RR=0.86, p<0.017, N=24) and large effect size (Hedges g=0.66), but did not decrease heterogeneity (I²=74.9). Of all cancer sites, only testicular cancer showed an RR value >1, although this was not significant and had a negligible effect size (RR=1.12, p=0.3, Hedges g=0.02). Following removal of testicular cancers the remaining data showed a decrease in risk (RR=0.87, p<0.025, N=41). Cancers of the head and neck showed a negative association with cancer risk (RR=0.83, p<0.05), with a large effect size (Hedges g=0.55), but high heterogeneity (I²=79.2%). RR did not reach statistical significance in the remaining cancer site categories (lung, testicular, obesity-associated, other). The data are consistent with a negative association between Cannabis use and nontesticular cancer, but there is low confidence in this result due to high heterogeneity and a paucity of data for many cancer types.

Self-reported reductions in tobacco and nicotine use following medical cannabis initiation: Results from a cross-sectional survey of authorized medical cannabis patients in Canada

BACKGROUND

Despite decades of campaigns aimed at reducing tobacco/nicotine (T/N) use and the development of many different T/N reduction and cessation strategies, the impacts on international public health remain significant. Some studies have found an association between medical and non-medical cannabis use and T/N use, although the evidence on whether cannabis/cannabinoids increase or decrease the odds of reducing or ceasing T/N use remain contradictory. This paper explores the self-reported use of cannabis and associated changes in T/N use among a Canadian medical cannabis patient population.

METHODS

This study examines the impact of medical cannabis on T/N use by comparing self-reported patterns of use before and after the initiation of medical cannabis. Participants completed an online cross-sectional survey examining demographics, patterns of medical cannabis use, and the impact of medical cannabis on the use of T/N and other substances. The survey also included novel measures examining whether patients intended to use medical cannabis to reduce T/N use or had experience with other pharmacological or psychobehavioral T/N cessation strategies. We conducted a series of descriptive analyses and univariate and multivariate logistic regressions to explore the potential association between primary variables of interest and T/N reduction and cessation.

RESULTS

In total, the study recruited 2102 individuals, of whom 650 were current or former T/N users. Following initiation of medical cannabis use 320 (49%) T/N users self-reported reductions in use, with 160 (24.6%) reporting no T/N use in the 30 days prior to the survey. Odds of T/N cessation were greater among those who were age 55 or older (Adjusted Odds Ratio [AOR] = 2.56, 95% Confidence Interval [CI] 1.53-4.26), or those who reported >25 T/N uses per day in the pre-period (AOR = 2.11, 95% CI 1.14-3.92). Specific intent to use medical cannabis to quit resulted in significantly greater odds of reducing T/N use (AOR = 2.79, 95% CI 1.49-5.22); however, involvement with traditional T/N cessation treatments (pharmacological or psychobehavioral) was negatively associated with T/N cessation (AOR 0.39, 95% CI 0.18-0.86).

CONCLUSIONS

Results from this retrospective survey of medical cannabis users suggest that initiation of medical cannabis use was associated with self-reported reductions and/or cessation of T/N use in nearly half of study participants. In light of the significant morbidity, mortality, and health care costs related to T/N dependence, future research should further evaluate the potential of cannabis-based treatments to support efforts to reduce or cease T/N use.

The Clinical Conundrum of Cannabis: Current Practices and Recommendations for Transplant Clinicians: An Opinion of the Immunology/Transplantation PRN of the American College of Clinical Pharmacy

Cannabis, or marijuana, comprises many compounds with varying effects. It has become a treatment option for chronic diseases and debilitating symptoms, and evidence suggests that it has immunomodulatory and antiinflammatory properties. Transplant centers are more frequently facing issues about cannabis, as indications and legalization expand. As of February 2020, 33 states and the District of Columbia have legalized medical cannabis, and 14 have legalized recreational cannabis. Moreover, 8 states have passed legislation prohibiting the denial of transplant listing solely based on cannabis use. Studies demonstrate the potential for significant pharmacokinetic and pharmacodynamic interactions between cannabis and immunosuppression. Additionally, safety concerns include increased risk of myocardial infarction, ischemic stroke, tachyarrhythmias, malignancy, neurocognitive deficits, psychosis, other neuropsychiatric disorders, cannabis use disorder, respiratory symptoms, and infection. A recent retrospective database study found a negative association between documented cannabis use disorder and graft survival, but little additional evidence exists evaluating this relationship. In the absence of robust clinical data, transplant centers need a clear, reasoned, and systematic approach to cannabis. The results of our national survey, unfortunately, found little consensus among institutions. As both recreational and medicinal cannabis become more ubiquitous nationwide, transplant centers will need to develop comprehensive policies to address its use.

Cannabis use among Canadian adults with cancer (2007-2016): results from a national survey

Background: The current study aims to evaluate the rates and associations of cannabis use among Canadian adults with cancer (2007-2016).Methods: Canadian Community Health Survey (CCHS) (2007-2016) was accessed and adult participants who answered yes to the question "Do you have cancer?" and who have complete information about cannabis use were included. Multivariable logistic regression was used to identify factors associated with cannabis use.Results: A total of 4667 participants who currently have cancer were included in the current analysis. The rate of cannabis use increased throughout the study (34.4% in 2015-2016 versus 27.7% in 2007-2008). The following factors were associated with cannabis use: younger age (OR: 3.64; 95% CI: 2.27-5.86; P<0.01); male sex (OR: 2.11; 95% CI: 1.80-2.48; P<0.01); white race (OR: 2.02; 95% CI: 1.46-2.78; P<0.01); single status (OR for married versus single: 0.38; 95% CI: 0.29-0.50; P<0.01) and higher income (OR for income < 20,000 versus income ≥ 80,000: 00.74; 95% CI: 0.56-0.99; P=0.04).Conclusions: Within this study cohort of Canadian adults with current cancer diagnosis, cannabis use is not uncommon. A history of cannabis use is associated with younger age, male sex, white race, non-married status, and higher income.

Marijuana Use and Sexual Risk Behavior Among Young Black Men Who Have Sex with Men in California

Young black men who have sex with men (YBMSM) are disproportionately affected by HIV and continue to experience higher rates of new HIV infections when compared to other population groups. As part of the Peer Promotion of Wellness and Enhanced Linkage to Resources Project, we examined problem marijuana use and the overall sexual risk profile of 250 YBMSM. Eighty percent reported prior use of marijuana in their lifetime (n = 200). Among those, problem marijuana use was correlated with problem use of alcohol (r = 0.51, p < 0.001) and other drugs (r = 0.29, p < 0.001); lower household income (r = - .22, p < .01); homelessness (r = 0.15, p < 0.05); incarceration (r = 0.16, p < 0.05); exchanging sex for money, drugs, or shelter (r = 0.18, p < 0.05); having sex with someone known or suspected of having HIV and/or an STI (r = 0.20, p < 0.01); having sex with someone known or suspected of being an injector (r = 0.24, p < 0.01); and having unprotected sex while under the influence of alcohol or drugs (r = 0.32, p < 0.001). The complex relationship between marijuana and sexual risk behavior was examined while accounting for the possible moderating effects of alcohol or other drugs. Problem marijuana, alcohol, and other drug use each made unique contributions to predicting risky sex behavior. A significant marijuana and other drug interaction was found to predict sexual risk behaviors. Future efforts should include holistic intervention approaches for YBMSM that consider factors facilitating high-risk sexual behaviors.

Review of Medicinal Use of Cannabis Derivatives and the Societal Impact of Legalization

Background:

In recent past, there has been a rush to legalize marijuana along with a lot of support for its medicinal uses. This review intends to discuss the medicinal uses of marijuana and its adverse effects based on the current available evidence. Furthermore, it discusses the impact of legalization of marijuana.

Methodology:

This was a narrative review for which a thorough literature search was conducted on the Medline and PubMed databases. A detailed search of the Internet to find relevant information on webpages was also performed.

Results:

High-quality evidence for the majority of medical indications of marijuana remains investigational. Most of the available literature compares it against placebos. Postlegalization usage of marijuana has increased.

Conclusion:

It would be prudent to wait for studies which prove beyond doubt the advantages of marijuana over the existing drugs and also outweigh its side effects and addiction potential. Moreover, further legalization of marijuana should only be considered after evaluating its effects at places where it is already legally available.

Heavy cannabis use, dependence and the brain: a clinical perspective

AIMS

To summarize and evaluate our knowledge of the relationship between heavy cannabis use, cannabis use disorder (CUD) and the brain.

METHODS

Narrative review of relevant literature identified through existing systematic reviews, meta-analyses and a PubMed search. Epidemiology, clinical representations, potential causal mechanisms, assessments, treatment and prognosis are discussed.

RESULTS

Although causality is unclear, heavy and dependent cannabis use is consistently associated with a high prevalence of comorbid psychiatric disorders and learning and memory impairments that seem to recover after a period of abstinence. Evidence regarding other cognitive domains and neurological consequences, including cerebrovascular events, is limited and inconsistent. Abstinence after treatment is only achieved in a minority of cases; treatment targeted at reduction in use appears have some success. Potential moderators of the impact of CUD on the brain include age of onset, heaviness of use, CUD severity, the ratio of ∆9-tetrahydrocannabinol to cannabidiol and severity of comorbid disorders.

CONCLUSIONS

Current evidence of long-term effects of daily cannabis use and cannabis use disorder on brain-related outcomes is suggestive rather than conclusive, but use is associated with psychiatric morbidity and with cognitive impairments that recover after a period of abstinence.

Cannabis-based medicines for chronic pain management: current and future prospects

PURPOSE OF REVIEW

The medicinal use of cannabis has recently become the focus of much medical, as well as political, attention. This reality of growing use but limited evidence creates unique dilemmas for the prescribing clinician. The purpose of this review is to explore current evidence and gaps in knowledge and offer some practical considerations.

RECENT FINDINGS

There is robust preclinical data regarding the relevance of the endocannabinoid system to many pain-relevant processes. However, evidence to support cannabis-based medicines clinical use is still lacking. The best evidence to date is in managing neuropathic pain, although whether effects are clinically significant remains undetermined. However, the safety profile of cannabinoids seems favorable, especially by comparison to other medications used for pain control.

SUMMARY

The endocannabinoid system is undoubtedly a new and exciting pharmaceutical target for chronic pain management, but transition from preclinical to clinical studies has so far proved difficult. Although it is reasonable to consider cannabinoids for otherwise unresponsive pain, care should be taken in frail clinical populations. As this has become a socioeconomic and political issue in which agendas often take precedence over due diligence, there is a pressing need for unbiased empirical data and high quality evidence to better inform prescribers and patients.

Cannabinoids Promote Progression of HPV-Positive Head and Neck Squamous Cell Carcinoma via p38 MAPK Activation

PURPOSE

Human papillomavirus (HPV)-related head and neck squamous cell carcinoma (HNSCC) is associated with daily marijuana use and is also increasing in parallel with increased marijuana use in the United States. Our study is designed to define the interaction between cannabinoids and HPV-positive HNSCC.

EXPERIMENTAL DESIGN

The expression of cannabinoid receptors CNR1 and CNR2 was analyzed using The Cancer Genome Atlas (TCGA) HNSCC data. We used agonists, antagonists, siRNAs, or shRNA-based models to explore the roles of CNR1 and CNR2 in HPV-positive HNSCC cell lines and animal models. Cannabinoid downstream pathways involved were determined by Western blotting and analyzed in a primary HPV HNSCC cohort with single-sample gene set enrichment analysis (ssGSEA) and the OncoGenome Positioning System (Onco-GPS).

RESULTS

In TCGA cohort, the expression of CNR1 and CNR2 was elevated in HPV-positive HNSCC compared with HPV-negative HNSCC, and knockdown of CNR1/CNR2 expression inhibited proliferation in HPV-positive HNSCC cell lines. Specific CNR1 and CNR2 activation as well as nonselective cannabinoid receptor activation in cell lines and animal models promoted cell growth, migration, and inhibited apoptosis through p38 MAPK pathway activation. CNR1/CNR2 antagonists suppressed cell proliferation and migration and induced apoptosis. Using whole-genome expression analysis in a primary HPV HNSCC cohort, we identified specific p38 MAPK pathway activation signature in tumors from HPV HNSCC patients with objective measurement of concurrent cannabinoid exposure.

CONCLUSIONS

Cannabinoids can promote progression of HPV-positive HNSCC through p38 MAPK pathway activation.

Cannabis Expectancies for Sleep

Up to 35% of adults in the United States suffer from sleep disturbances, which covary with a host of negative mental and physical health outcomes. Previous research suggests that cannabis' sedative effects may be associated with improved sleep. The present study examined the self-reported effect of cannabis use on individual's sleep-related problems. Participants included 311 individuals recruited online, who reported both sleep-related problems and cannabis use. Analyses revealed that participants expected cannabis to decrease the incidence of sleep-related problems, including allowing participants to have an earlier bedtime, to fall asleep more quickly, and to have a longer night's sleep. Moreover, expectancies about the influence of cannabis on sleep negatively covaried with cannabis-related problems. These findings suggest that individuals believe using cannabis might positively influence their sleep quality and believing so may be protective against cannabis problems. Randomized control trials of cannabis for insomnia appear justified.

Hookah and Electronic Inhalant Device Use and Perceptions Among African American Youth and Young Adults: Are We Asking the Right Questions?

Objectives. Survey items used in surveillance systems to assess the use of emerging products like hookah and electronic inhalant devices (EIDs) may not match definitions used by high-risk populations. This qualitative study explored how African American youth and young adults (YYAs) (1) use hookah and EIDs and (2) identify patterns in the ways they describe and organize these products. Design. Individual in-person interviews were conducted among a sample of continuation high school and vocational school students in southern California. Participation was limited to those who had ever tried at least one tobacco product, self-identified as African American, and were between the ages of 14 and 26 years (n = 28). We conducted a content analysis to identify patterns in perceptions and use of these products. Results. African American YYAs recognized and described traditional hookah based on physical attributes, but for EIDs, including e-cigarettes, e-hookah, and vape pens, YYAs focused on reasons for using the product. Three primary categories emerged for reasons YYA used specific products: nicotine content and quitting, social facilitation, and use with marijuana. E-cigarettes were identified as quitting aids and as having nicotine but were not considered addictive. The term hookah recalled both the traditional and electronic pen-type products for YYAs. The terms vapes, hookah, wax pens, and others are used in the context of describing product use with marijuana. Conclusions. A better understanding of why African American YYAs use these products is needed to develop better measures for accurate rates of use, uncover differences in use between product types, and to develop effective prevention messaging.

Aerosol Gas-Phase Components from Cannabis E-Cigarettes and Dabbing: Mechanistic Insight and Quantitative Risk Analysis

Consumption of cannabis by nontraditional methods has surged since the advent of legalization in North America and worldwide. Inhaling cannabis extracts using vaporizers and via dabbing has risen in popularity, while concerns over product safety have not hindered their proliferation. The work herein is the first step toward assessing the safety of vaporizing and dabbing concentrated cannabis extracts as a function of gas-phase reaction products. The gas-phase thermal degradants of Δ⁹-tetrahydrocannabinol (THC) have not been previously investigated. It was found that users may be exposed to concerning degradants such as methacrolein, benzene, and methyl vinyl ketone when using cartridge vaporizers and dabbing. It was shown that THC alone and mixed with terpenes generated similar degradation products and, most notably, elevated levels of isoprene. Importantly, it was shown that added terpenes led to higher levels of gas-phase products compared to THC alone. To estimate cancer and noncancer risks associated with exposure to these and other degradants, quantitative risk assessment was applied to experimentally determined values for dabbing and vaping and literature-sourced levels of hazardous components in cannabis smoke. Overall, gas-phase aerosol products had significantly lower values in dabbing and vaporizing compared to cannabis smoking, although these results should be interpreted in light of potential variations in degradant levels due to disparate usage patterns and the dangers of the higher aerosol concentration of THC.

What is the evidence for cannabis use in otolaryngology?: A narrative review

OBJECTIVES

Review of the English literature for all studies involving cannabis and Otolaryngology.

METHODS

PubMed was searched using a combination of the terms cannabis, marijuana, otolaryngology, hearing, tinnitus, vestibular, rhinology, sinusitis, laryngology, voice, airway, head and neck, head and neck cancer, facial trauma, spasm, pediatric otolaryngology, sleep medicine, obstructive sleep apnea, and other variations. Literature included in the review provided substantive research on cannabis in Otolaryngology.

RESULTS

Seventy-nine unique publications were found in the literature. The majority were published in the last decade and pertain to the subspecialty of Head and Neck; specifically, its association with incident cancers. A small number of studies exist that suggest cannabis may be a useful therapy for Otolaryngological patients suffering from blepharospasm, the effects of radiation, and the psychological sequelae of receiving a cancer diagnosis.

CONCLUSION

Further research is required to determine the potential therapeutic roles and adverse effects of cannabis on conditions related to Otolaryngology. This study serves the Otolaryngological researcher with the most current, comprehensive literature review for the exploration into possible projects to undertake.

Opportunities for cannabis in supportive care in cancer

Cannabis has the potential to modulate some of the most common and debilitating symptoms of cancer and its treatments, including nausea and vomiting, loss of appetite, and pain. However, the dearth of scientific evidence for the effectiveness of cannabis in treating these symptoms in patients with cancer poses a challenge to clinicians in discussing this option with their patients. A review was performed using keywords related to cannabis and important symptoms of cancer and its treatments. Literature was qualitatively reviewed from preclinical models to clinical trials in the fields of cancer, human immunodeficiency virus (HIV), multiple sclerosis, inflammatory bowel disease, post-traumatic stress disorder (PTSD), and others, to prudently inform the use of cannabis in supportive and palliative care in cancer. There is a reasonable amount of evidence to consider cannabis for nausea and vomiting, loss of appetite, and pain as a supplement to first-line treatments. There is promising evidence to treat chemotherapy-induced peripheral neuropathy, gastrointestinal distress, and sleep disorders, but the literature is thus far too limited to recommend cannabis for these symptoms. Scant, yet more controversial, evidence exists in regard to cannabis for cancer- and treatment-related cognitive impairment, anxiety, depression, and fatigue. Adverse effects of cannabis are documented but tend to be mild. Cannabis has multifaceted potential bioactive benefits that appear to outweigh its risks in many situations. Further research is required to elucidate its mechanisms of action and efficacy and to optimize cannabis preparations and doses for specific populations affected by cancer.

Perceived Effectiveness of Anti-Marijuana Messages in Adult Users and Nonusers: An Examination of Responses to Messages About Marijuana's Effects on Cognitive Performance, Driving, and Health

OBJECTIVE

Marijuana use is associated with negative cognitive and health outcomes and risky driving. Given the rapidly changing policies regarding legal recreational and medicinal marijuana use, it is important to examine what types of marijuana prevention messages may be effective in minimizing such outcomes. This study examined cognitive and affective responses to anti-marijuana public health messages in a sample of adult marijuana users and nonusers to determine the correlates of perceived message effectiveness.

METHOD

Participants (N = 203; mean age = 37.7 years) were adult marijuana users and nonusers recruited via Amazon Mechanical Turk (August 2017). After completing self-report measures of marijuana use, they viewed six anti-marijuana messages presented in a random order, addressing marijuana's effects in each of three topic areas: cognitive performance, driving, and adverse health outcomes (e.g., two messages per topic). Participants completed assessments of cognitive and affective perceptions after viewing each message. For each message topic, a linear regression model was used to determine which cognitive and affective perceptions were most predictive of perceived message effectiveness.

RESULTS

For all message topics, nonusers perceived the messages as more effective than did users (p < .001). In the majority of analyses, greater message effectiveness was associated with increased perceived harm of marijuana and increased liking of the message. For driving and health messages, greater message effectiveness was also significantly correlated with lower pleasant affect.

CONCLUSIONS

The findings suggest that audience perceptions may be uniquely predictive of message effectiveness, depending on the topic.

Maternal use of illicit drugs, tobacco or alcohol and the risk of childhood cancer before 6 years of age

BACKGROUND

Previous studies provide conflicting evidence of a link between maternal substance use and risk of childhood cancer.

METHODS

We analyzed a cohort of 785,438 newborns in Quebec (2006-2016). We identified infants whose mothers had problematic illicit drug, tobacco, or alcohol use before or during pregnancy. The primary outcomes were childhood hematopoietic cancer or solid tumors within 0-5 years of age. Using Cox proportional hazards models, we computed hazard ratios (HR) and 95% confidence intervals (CI) for the association between maternal substance use and childhood cancer, adjusted for potential confounders.

RESULTS

A total of 925 cases of cancer occurred during 3.5 million person-years of follow-up. Children exposed to any maternal substance use had marginally elevated cancer incidence rates compared with unexposed children (29.4 vs. 26.1 per 100,000 person-years). Maternal illicit drug use was associated with the risk of acute lymphoblastic leukemia (HR 1.63, 95% CI 0.79-3.36) and fibrosarcoma (HR 2.11, 95% CI 0.86-5.16). Maternal tobacco use was associated with acute myeloid leukemia (HR 2.01, 95% CI 0.72-5.60) and fibrosarcoma (HR 2.13, 95% CI 1.05-4.32), but a weak association with neuroblastoma (HR 1.21, 95% CI 0.61-2.40) and renal tumors (HR 1.14, 95% CI 0.42-3.13) also appeared to be present.

CONCLUSIONS

We found a potential association between maternal substance use and certain types of early childhood cancer. Although effects were modest, maternal substance use may contribute to some types of childhood cancer, especially leukemia and fibrosarcoma.

A commentary on the medicinal use of marijuana

Background

Lately, the number of people using marijuana in the USA has dramatically increased. In 2018, many states have legalized marijuana use for both medical and recreational purposes, thus exploring the evidence behind medical marijuana use became essential. Muslim majority countries enforce rigorous rules as marijuana has been a long-debated issue due to the stigma associated with its use as a treatment. Marijuana has a high beneficial effect in managing chronic pain in adults and relieving spasticity symptoms in multiple sclerosis, obstructive sleep apnea syndrome, and fibromyalgia. As well as, used as pain management, and as anti-emetic in treatment of chemotherapy-induced vomiting and nausea. Marijuana is requested from more than one-third of posttraumatic stress disorder patients due to its significant clinical improvement in nightmares and subsidence disorder symptoms.

Marijuana adversely affects the body’s resistance to many infections, compromising their immune response. Its recreational use has led to an increasing trend in the occurrence of major acute cardiovascular events as stroke, epilepsy, acute myocardial infarction, congestive heart failure, and arrhythmia.

Conclusion

Many countries started to allow medicinal use of marijuana due to its beneficial effect in managing chronic pain, spasticity symptoms in multiple sclerosis, obstructive sleep apnea syndrome, fibromyalgia, and posttraumatic stress disorder. But literature lacks benefit-harm analysis for marijuana usage in medicine. Therefore, evidence-based report of short- and long-term health effects of marijuana use—both harmful and beneficial effects—is crucial for further marijuana prescription in healthcare settings.

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

BACKGROUND

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

METHODS

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

RESULTS

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

CONCLUSIONS

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

Is Cannabis Use Associated with Sedentary Behavior during Leisure Time? A Study in Canada, 2011-2012

BACKGROUND

Sedentary behavior, defined as lying or sitting, is a global health concern. As researchers continue to identify modern-day risk factors for sedentary behavior, few have explored the role of illicit drug use.

OBJECTIVE

To examine the association between leisure-time sedentary behavior and cannabis use, in adolescents and adults.

METHODS

We conducted a cross-sectional study relating cannabis use to total leisure-time sedentary behavior (hr/wk using the computer, playing video games, watching television or videos, and reading for leisure) using data from the 2011-2012 Canadian Community Health Survey (CCHS), a population-based survey of Canadians age ≥12 years. Analyses were possible for 48,240 respondents in Saskatchewan, Ontario, and Nunavut who reported on sedentary behavior. We used logistic regression modeling to relate frequency of cannabis use (never, occasional, heavy) to high-risk sedentary behavior (<35 versus ≥35 hr/wk) overall and stratified by sex, age, and rural location.

RESULTS

Approximately 80% of respondents were ≥25 years old. In the fully-adjusted model, the odds of ≥35 hr/wk of sedentary behavior were 80% higher for heavy cannabis users versus never users (OR = 1.8, 95% CI: 1.4-2.3); in occasional cannabis users, the odds were 30% higher (OR = 1.3, 95% CI: 1.1-1.5). In stratified analyses, odds ratios were statistically significant among adults age 25-44 years and people living in nonrural settings. Conclusions/Importance: Our findings support dual lifestyle interventions targeting heavy cannabis use and excessive sedentary behavior simultaneously. Moreover, leisure-time sedentary behavior should be considered as a covariate in future epidemiologic models relating cannabis to health.

The Relationship Between Tobacco and Cannabis Use: A Review

BACKGROUND

Based on the prevalence and health implications of tobacco and cannabis use, aiming to reduce their use, especially among youth, is a sound objective at both the individual and public health level. A proper understanding of the relationships between tobacco and cannabis use may help to achieve this goal.

OBJECTIVES

To review the relationships between tobacco and cannabis use.

METHODS

A selective review of the literature.

RESULTS

We present an overview of the motivations for tobacco and cannabis use, and their perceived harmfulness. The article then reviews the gateway theory, reverse gateway theory, route of administration theory, and common liability theory. We describe the link between co-use and dependence symptoms, and the substitution phenomenon between tobacco and cannabis use. Three forms of simultaneous use-mulling, blunt smoking, and chasing-and their impacts are explained. We summarize the impact of tobacco use on cannabis (and vice versa) treatment outcomes, and, finally, review new treatments that simultaneously target tobacco and cannabis dependence. Most of the literature reviewed here relates to substance use among adolescents and young adults.

CONCLUSIONS

The use of tobacco and cannabis-two of the most widely used substances around the world-are strongly intertwined in several respects. Both health professionals and researchers should have well-informed views on this issue to better evaluate, understand, inform, and provide care to their patients.

Marijuana and head and neck cancer: an epidemiological review

Background

Marijuana is the most widely used illicit substance in Canada. To date, no conclusive study has looked at the epidemiologic basis of marijuana use and head and neck cancer (HNC). Due to the imminent recreational legalization of marijuana in Canada, the epidemiologic relationship between marijuana use and HNC is becoming increasingly important.

Objective

To examine the epidemiologic characteristics of HNC patients who are recreational marijuana users.

Methods

This study was conducted at a single tertiary care centre from 2011 to 2014. Patients were enrolled consecutively at time of diagnosis of malignancy. Data was prospectively collected and included socioeconomic factors, alcohol/tobacco history, tumor characteristics, and treatment modality. Marijuana use was defined as current usage on an at least weekly basis.

Results

Eight hundred seventy-nine patients met inclusion and exclusion criteria. Seventy-four (8.4%) patients were classified as marijuana users. Compared to non-users, marijuana users were less likely to be married (p = 0.048) and had less significant tobacco smoking history (p = 0.004). There were no significant differences between other socioeconomic factors or local and regional disease (p > 0.05). Marijuana users differed in the proportion of cancers stratified by primary site (p < 0.0001), with higher rates of p16+ oropharyngeal cancers, and treatment modality (p < 0.0001), with more use of chemoradiation.

Conclusions

HNC patients who were marijuana users were less likely to be married and smoke tobacco. They have a distinct cancer site prevalence and are more likely to be treated by chemoradiation. Understanding the epidemiological breakdown of marijuana users amongst HNC patients will be a useful adjunct for future studies.

Electronic supplementary material

The online version of this article (10.1186/s40463-018-0319-2) contains supplementary material, which is available to authorized users.

Transition to drug co-use among adolescent cannabis users: The role of decision-making and mental health

BACKGROUND

Co-use of cannabis and drugs other than cannabis (DOTC) influences the risk of experiencing cannabis disorders. Accordingly, we explored whether speed of transition to drug co-use, the number of DOTC used, and/or being an experimental cannabis-only user, a regular cannabis-only user, or a regular cannabis user who co-uses DOTC (i.e., cannabis-plus user) were associated with decision-making (DM), mental health disorder symptoms, or cannabis use-related characteristics.

METHODS

We analyzed baseline data from a sub-sample of 266 adolescent (ages 14 to 16) cannabis users (CU) participating in an ongoing longitudinal study. Assessments included semi-structured interviews, self-report questionnaires, and measures of drug use, DM (measured via the Iowa Gambling Task), mental health disorders, and cannabis use-related problems.

RESULTS

Endorsing a larger number of mood disorders symptoms was associated with being a regular cannabis-plus user rather than a regular cannabis-only user (AOR = 1.08, C.I.95% 1.01, 1.15). Poorer DM was associated with a faster transition to co-use, such that for each one unit increase in DM performance, the years to onset of drug co-use increased by 1% (p = 0.032). Endorsing a larger number of cannabis use-related problems was positively associated with endorsing a larger number of DOTC used (p = 0.001).

CONCLUSIONS

This study provides new evidence on the process of drug co-use among CU. Specifically, mood disorder symptoms were associated with use of DOTC among regular CU. Furthermore, poorer DM was associated with a faster transition to drug co-use. Poorer DM and mood disorder symptoms may aggravate or accelerate the onset of adverse consequences among adolescent CU.

Tobacco, alcohol and illicit drugs during pregnancy and risk of neuroblastoma: systematic review

OBJECTIVE

To determine whether prenatal and perinatal maternal consumption of alcohol, tobacco and/or illicit drugs is associated with risk of neuroblastoma.

DATA SOURCES

Medline and Embase (both from inception to February 2017), and reference lists of included studies.

STUDY SELECTION

To be eligible, a study had to be an original report including data on intake of alcohol, tobacco smoking and/or consumption of illicit drugs during pregnancy and risk of neuroblastoma in the child.

DATA EXTRACTION

From eligible studies, data study characteristics as well as effect measures and confounders were extracted. We assessed unadjusted and confounder-adjusted estimates, performed risk of bias analysis, constructed random-effects models and assessed heterogeneity.

RESULTS

We identified 14 case-control studies (1987-2016) involving a total of 3114 children with neuroblastoma. Meta-analysis of unadjusted estimates showed an association between alcohol (OR 1.26; 95% CI 1.07 to 1.49), tobacco (OR 1.22; 95% CI 1.04 to 1.44) and illicit drug consumption during pregnancy and risk of neuroblastoma during childhood, with illicit drug consumption showing the strongest association (OR 3.26; 95% CI 1.36 to 7.86). However, adjusted estimates were highly heterogeneous.

LIMITATIONS

All studies were at high risk of bias.

CONCLUSIONS

Smoking, alcohol or illicit drugs during pregnancy might play a role in the development of neuroblastoma. However, well-designed studies are needed to assess whether these exposures are causal and whether time period during pregnancy, dose or co-consumption of substances is critical.

TRIAL REGISTRATION NUMBER

Registration number CRD42016036165.

The adverse health effects and harms related to marijuana use: an overview review

BACKGROUND

With impending marijuana legislation in Canada, a broad understanding of the harms associated with marijuana use is needed to inform the clinical community and public, and to support evidence-informed public policy development. The purpose of the review was to synthesize the evidence on adverse health effects and harms of marijuana use.

METHODS

We searched MEDLINE, The Cochrane Database of Systematic Reviews, Embase, PsycINFO, the Cumulative Index to Nursing and Allied Health Literature, and the Health Technology Assessment Database from the inception of each database to May 2018. Given that systematic reviews evaluating one or other specific harm have been published, this is an overview review with the primary objective of assessing a health effect or harm. Data on author, country and year of publication, search strategy and results, and outcomes were extracted. Quality was assessed using the AMSTAR (A Measurement Tool to Assess Systematic Reviews) checklist.

RESULTS

The final analysis included 68 reviews. Evidence of harm was reported in 62 reviews for several mental health disorders, brain changes, cognitive outcomes, pregnancy outcomes and testicular cancer. Inconclusive evidence was found for 20 outcomes (some mental health outcomes, other types of cancers and all-cause mortality). No evidence of harm was reported for 6 outcomes.

INTERPRETATION

Harm was associated with most outcomes assessed. These results should be viewed with concern by physicians and policy-makers given the prevalence of use, the persistent reporting of a lack of recognition of marijuana as a possibly harmful substance and the emerging context of legalization for recreational use.

Cannabis Use and Incidence of Testicular Cancer: A 42-Year Follow-up of Swedish Men between 1970 and 2011

Background: Given current drug policy reforms to decriminalize or legalize cannabis in numerous countries worldwide, the current study assesses the relation between cannabis use and the development of testicular cancer.Methods: The study included a population-based sample (n = 49,343) of young men ages 18-21 years who underwent conscription assessment for Swedish military service in 1969-1970. The conscription process included a nonanonymous questionnaire eliciting information about drug use. Conscription information was linked to Swedish health and administrative registry data. Testicular cancers diagnosed between 1970 and 2011 were identified by International Classification of Diseases-7/8/9/10 testicular cancer codes in the Swedish National Patient Register, the Cancer Register, or the Cause of Death Register. Cox regression modeling was used to estimate the hazards associated with cannabis use and time to diagnosis of testicular cancer.Results: No evidence was found of a significant relation between lifetime "ever" cannabis use and the subsequent development of testicular cancer [n = 45,250; 119 testicular cancer cases; adjusted HR (aHR), 1.42; 95% confidence interval (CI), 0.83-2.45]. "Heavy" cannabis use (defined as usage of more than 50 times in lifetime, as measured at conscription) was associated with the incidence of testicular cancer (n = 45,250; 119 testicular cancer cases; aHR 2.57; 95% CI, 1.02-6.50).Conclusions: The current study provides additional evidence to the limited prior literature suggesting cannabis use may contribute to the development of testicular cancer.Impact: Emerging changes to cannabis drug policy should consider the potential role of cannabis use in the development of testicular cancer. Cancer Epidemiol Biomarkers Prev; 26(11); 1644-52. ©2017 AACR.

Association of marijuana use with oral HPV infection and periodontitis among Hispanic adults: Implications for oral cancer prevention

BACKGROUND

Despite limited data, research suggests that marijuana use is associated with oral HPV infection and periodontitis, two potential oropharyngeal cancer risk factors. We assessed these associations in a Hispanic adult population in Puerto Rico.

METHODS

A cross-sectional study of 735 adults assessed marijuana use, determined through an audio computer-assisted self-interview, and periodontitis and self-collection of oral HPV samples following the National Health and Nutrition Examination Survey methodology. The Centers of Disease Control and Prevention/American Academy of Periodontology definition was used for periodontitis. HPV typing was performed using polymerase chain reaction with modified L1 consensus primers (MY09/MY11).

RESULTS

26.5% of adults reported lifetime use of marijuana, 2.7% were frequent users (lifetime use ≥ 26 times, past year use ≥ 6 times, and past 30-day use ≥2 times), 5.7% had oral HPV infection, and 20.1% had severe periodontitis. The multivariate logistic regression analysis showed that frequent marijuana users were more likely to have severe periodontitis (OR = (2.93, 95%: 1.08-7.96)) than never/once lifetime users after adjusting for age, sex, healthcare coverage, smoking, binge drinking, number of oral sex partners, and oral HPV infection. However, frequent marijuana use was not associated with oral HPV infection.

CONCLUSION

Marijuana use was associated with periodontitis, but not with oral HPV infection. Further evaluation of the role of marijuana use in oral HPV infection and periodontitis may inform novel preventive public health strategies, as marijuana users could be at increased risk of oral cancer.

Marijuana Use and Perceptions of Risk and Harm: A Survey among Canadians in 2016

OBJECTIVES

To describe marijuana use by Canadians and their perceptions of risk and harm.

DESIGN

A cross-sectional, structured, online and telephone survey.

PARTICIPANTS

A nationally representative sample of Canadians.

METHODS

This survey used random probability sampling and targeted respondents based on age, sex, region and their expected response rate.

RESULTS

Of the 20% of respondents reporting marijuana use in the past 12 months, they were more likely to be younger and male. The most common form of use was smoking, 79%. When asked about harmfulness, 42% and 41% responded that they considered marijuana more harmful than helpful to mental health and to physical health, respectively. When asked about driving under the influence, 71% responded that it was the same as alcohol.

CONCLUSION

This research is important for health providers and policy makers seeking to maximize public health through clinical and legislative reform of non-medical use of marijuana.

Evidence for the use of "medical marijuana" in psychiatric and neurologic disorders

Introduction

Cannabis is listed as a Schedule I substance under the Controlled Substances Act of 1970, meaning the US federal government defines it as an illegal drug that has high potential for abuse and no established medical use; however, half of the states in the nation have enacted "medical marijuana" (MM) laws. Clinicians must be aware of the evidence for and against the use of MM in their patients who may consider using this substance.

Methods

A PubMed database search was performed using the text string: "Cannabis"[Mesh] OR "Marijuana Abuse"[Mesh] OR "Medical Marijuana"[Mesh] OR "Marijuana Smoking"[Mesh] OR "cannabi*" OR "tetrahydrocannabinol." The search was further limited to randomized clinical trial publications in English on human subjects to identify articles regarding the therapeutic use of phytocannabinoids for psychiatric and neurologic disorders. Commercially available products (ie, dronabinol, nabilone, nabiximols) and synthetic cannabinoids were excluded from the review.

Results

Publications were identified that included patients with dementia, multiple sclerosis, Parkinson disease, Huntington disease, schizophrenia, social anxiety disorder, depression, tobacco use disorder, and neuropathic pain.

Discussion

There is great variety concerning which medical conditions are approved for treatment with MM for either palliative or therapeutic benefit, depending on the state law. It is important to keep an evidence-based approach in mind, even with substances considered to be illegal under US federal law. Clinicians must weigh risks and benefits of the use of MM in their patients and should ensure that patients have tried other treatment modalities with higher levels of evidence for use when available and appropriate.

Updates on the epidemiology and risk factors for penile cancer

Penile cancer is a rare neoplasm representing less than 1% of all malignancies in the USA and Europe but is a significant public health hazard in the developing world. Male neonatal circumcision has been associated with a dramatic decrease in penile cancer rates with countries such as Israel, where circumcision is widely performed, having the lowest incidence in the world at <0.1% of malignancies. Many risk factors have been identified for penile cancer including phimosis, lack of circumcision, obesity, lichen sclerosis, chronic inflammation, smoking, UVA phototherapy, socioeconomic status, human papillomavirus (HPV) infection and immune compromised states. The relationship between these factors and invasive disease varies and continues to be investigated. Our objective was to present a contemporary overview of the epidemiology and risk factors for invasive penile cancer.

Smoking and Disease Outcomes in Patients With Malignant Germ Cell Tumors

BACKGROUND

To our knowledge, no studies have evaluated the association between smoking and stage at diagnosis or survival among men with germ cell tumors (GCTs). We therefore evaluated the association between smoking and GCT presentation and outcomes.

METHODS

Electronic medical records of 1161 patients with GCT treated at Dana-Farber Cancer Institute between 1997 and 2013 were reviewed. Outcomes of interest were stage at diagnosis, relapse from clinical stage I (CSI) disease, relapse after first-line chemotherapy, and death from disease. Logistic regression models evaluated the association between smoking and tumor characteristics at diagnosis. Multivariable Cox proportional hazards regression was used to calculate hazard ratios (HRs) and 95% confidence intervals (CIs) for the association between smoking at diagnosis and risk of relapse and GCT cancer death.

RESULTS

In men diagnosed with CSI disease, smokers were 86% more likely to have a large tumor (≥ 4 cm) compared with nonsmokers (odds ratio [OR] 1.86; 95% CI, 1.28-2.71) and had a statistically significant increased risk of relapse (HR 2.05; 95% CI, 1.41-2.97). Among men with metastatic disease at diagnosis, the heaviest smokers (> 15 pack-years) were more likely to present with intermediate- or poor-risk disease compared with nonsmokers (OR 3.12; 95% CI, 1.29-7.55) and any smoking was associated with a statistically significant increased risk of relapse (HR 1.86; 95% CI, 1.26-2.73) and GCT death (HR 2.56; 95% CI, 1.55-4.23).

CONCLUSION

Smoking is associated with more advanced disease at diagnosis and poorer GCT outcomes, including increased risk of relapse, for both CSI and metastatic disease.

Scientific Advances in Thoracic Oncology 2016

Lung cancer care is rapidly changing with advances in genomic testing, the development of next-generation targeted kinase inhibitors, and the continued broad study of immunotherapy in new settings and potential combinations. The International Association for the Study of Lung Cancer and the Journal of Thoracic Oncology publish this annual update to help readers keep pace with these important developments. Experts in thoracic cancer and care provide focused updates across multiple areas, including prevention and early detection, molecular diagnostics, pathology and staging, surgery, adjuvant therapy, radiotherapy, molecular targeted therapy, and immunotherapy for NSCLC, SCLC, and mesothelioma. Quality and value of care and perspectives on the future of lung cancer research and treatment have also been included in this concise review.

The Use of Medical Marijuana in Cancer

The use of medical marijuana in cancer care presents a dilemma for both patients and physicians. The scientific evidence is evolving, yet much of the known information is still insufficient to adequately inform patients as to risks and benefits. In addition, evidence-based dosing and administration information on medical marijuana is lacking. Medical marijuana is now legal, on some level, in 24 states plus the District of Columbia, yet is not legal on the federal level. This review addresses the current state of the research, including potential indications, risks and adverse effects, preliminary data on anticancer effects, as well as legal and quality issues. A summary of the clinical trials underway on medical marijuana in the oncology setting is discussed.