The Cannabis Gray Market: A Case for Cannabis Regulatory Science Research.

The cannabis gray market poses significant public health concerns and remains a major threat to consumer and/or potential consumer uptake of regulated cannabis markets in jurisdictions with legal state-sponsored cannabis programs. In this perspective, we provide an overview of the cannabis gray market, and describe an integrated epidemiological and regulatory science framework to study the gray market. Using tobacco regulatory science as a guide, we introduce example cannabis regulatory science research activities as a means to improve the field's understanding of the cannabis gray market. Cannabis regulatory science is a developing field that can improve our understanding of the cannabis regulatory ecosystem and provide regulatory officials and policymakers alike with much needed data to inform regulatory decision-making and improve the success and uptake of state-sponsored cannabis programs.

Youth and Young Adults' Knowledge and Perceptions of Risks and Benefits Regarding Cannabis Products: A Cross-Sectional Analysis of Over 1,700 Individuals.

Canada legalized the use of non-medical cannabis in 2018. This study examines youth and young adults' knowledge and perceptions of harms, benefits, and education around cannabis use since legalization. An online survey was completed by a convenience sample of 1,759 individuals aged 12-25 years living in Manitoba, Canada. Most participants (n = 1,525, 86.7%) reported receiving education on the potential effects/harms related to cannabis; the most common topics included driving and cannabis use (79.9%), the mental harms of cannabis (67.4%), and addiction and dependency (66.3%). Youth who reported using cannabis more than once (n = 1,203) were more knowledgeable about the effects of cannabis than youth who never used cannabis or used cannabis once (n = 580; mean score: 6.6 versus 5.7 out of 8, respectively; p < .001). Vaping cannabis oil was perceived as the most harmful cannabis product among all participants. Among participants with experience using cannabis, the most frequently reported benefits were relaxation, improved sleep, and enhanced enjoyment of food/music. Half of the participants reported ever being in a car with someone driving high, of which, 40% of these participants reported doing so in the last 30 days. Future tailored education is needed to address knowledge related to cannabis use among youth and young adults who use and do not use cannabis.

Isolation and characterization of synthesis intermediates and side products in hexahydrocannabiphorol.

After the Swiss ban of hexahydrocannabinol (HHC) in March 2023, other semisynthetic dibenzopyran cannabinoids emerged on the Swiss gray market. Hexahydrocannabiphorol (HHCP) was the most prominent of them due to its potent cannabimimetic effects, as anecdotal reports from recreational users suggest. In October 2023, a class wide ban of dibenzopyran cannabinoids was introduced in Switzerland to prevent new similar substances from entering the drug market. Various vendors in online shops claim that HHCP is made from CBD, even though they possess different alkyl chain lengths. An HHCP sample was analyzed by gas chromatography coupled to mass spectrometry (GC-MS), showing that a mixture of molecules with the same or a similar molecular mass as HHCP was present. Six different substances could be isolated from this sample using column chromatography. Four phenols ((9R)-HHCP, iso-HHCP, cis-HHCP, and abn-HHCP) and two ketones (possible intermediates to (9R)-HHCP and abn-HHCP) were identified by various nuclear magnetic resonance spectroscopy (NMR) techniques. (9S)-HHCP was obtained in an impure fraction. In addition, a fraction was obtained that showed characteristic molecular and fragment ions consistent with bisalkylated products from the synthesis of similar compounds. The presence of abnormal cannabinoids (abn-HHCP) and bisalkylated cannabinoids is a confirmation that this sample was produced purely synthetically as initially suspected, as these compounds have not been reported in Cannabis. Chiral derivatization of the phenols with Mosher acid chlorides showed that only iso-HHCP was present as a scalemic mixture, indicating a good stereocontrol of this synthetic procedure.

Exploring Twitter chatter to assess the type and availability of cannabis-related products in Thailand.

Cannabis-related tweets were collected between January and April 2022 to estimate the availability and characteristics of cannabis products advertised on Twitter amid the legalization of recreational cannabis in Thailand. The Twitter API was called using the tweepy Python library to collect cannabis-related tweets in the Thai language. A total of 185,558 unique tweets were collected over the duration of the data collection period based on 83 search terms. Twenty thousand random tweets were manually coded by four Thai native speakers to assess the volume and characteristics of tweets proposing cannabis. 72.6% of collected tweets from the 20,000 random samples were coded as relevant to the study. 54.6% of relevant tweets were advertising cannabis products, 29.8% were personal communications, and 15.6% were related to news or media content. Among the tweets that advertised cannabis products, 94.4% proposed cannabis flower, 2.4% cannabis edibles and 1.8% cannabis concentrates. Consumption of potent forms of cannabis such as cannabis edibles and concentrates increase the risk of harmful side-effects, especially in a population with limited knowledge about these products. Our findings call for additional monitoring efforts and for increasing the public awareness on potent cannabis products emerging in Thailand.

Protocol for a pragmatic trial of Cannabidiol (CBD) to improve chronic pain symptoms among United States Veterans.

BACKGROUND: Chronic pain affects over 100 million Americans, with a disproportionately high number being Veterans. Chronic pain is often difficult to treat and responds variably to medications, with many providing minimal relief or having adverse side effects that preclude use. Cannabidiol (CBD) has emerged as a potential treatment for chronic pain, yet research in this area remains limited, with few studies examining CBD's analgesic potential. Because Veterans have a high need for improved pain care, we designed a clinical trial to investigate CBD's effectiveness in managing chronic pain symptoms among Veterans. We aim to determine whether CBD oral solution compared to placebo study medication is associated with greater improvement in the Patient Global Impression of Change (PGIC). METHODS: We designed a randomized, double-blind, placebo-controlled, pragmatic clinical trial with 468 participants. Participants will be randomly assigned in a 1:1 ratio to receive either placebo or a CBD oral solution over a 4-week period. The trial is remote via a smartphone app and by shipping study materials, including study medication, to participants. We will compare the difference in PGIC between the CBD and placebo group after four weeks and impacts on secondary outcomes (e.g., pain severity, pain interference, anxiety, suicide ideation, and sleep disturbance). DISCUSSION: Once complete, this trial will be among the largest to date investigating the efficacy of CBD for chronic pain. Findings from this clinical trial will contribute to a greater knowledge of CBD's analgesic potential and guide further research. Given the relative availability of CBD, our findings will help elucidate the potential of an accessible option for helping to manage chronic pain among Veterans. TRIAL REGISTRATION: This protocol is registered at clinicaltrials.gov under study number NCT06213233.

Activity-based detection of synthetic cannabinoid receptor agonists in plant materials.

BACKGROUND: Since late 2019, fortification of 'regular' cannabis plant material with synthetic cannabinoid receptor agonists (SCRAs) has become a notable phenomenon on the drug market. As many SCRAs pose a higher health risk than genuine cannabis, recognizing SCRA-adulterated cannabis is important from a harm reduction perspective. However, this is not always an easy task as adulterated cannabis may only be distinguished from genuine cannabis by dedicated, often expensive and time-consuming analytical techniques. In addition, the dynamic nature of the SCRA market renders identification of fortified samples a challenging task. Therefore, we established and applied an in vitro cannabinoid receptor 1 (CB1) activity-based procedure to screen plant material for the presence of SCRAs. METHODS: The assay principle relies on the functional complementation of a split-nanoluciferase following recruitment of ß-arrestin 2 to activated CB1. A straightforward sample preparation, encompassing methanolic extraction and dilution, was optimized for plant matrices, including cannabis, spiked with 5 µg/mg of the SCRA CP55,940. RESULTS: The bioassay successfully detected all samples of a set (n = 24) of analytically confirmed authentic Spice products, additionally providing relevant information on the 'strength' of a preparation and whether different samples may have originated from separate batches or possibly the same production batch. Finally, the methodology was applied to assess the occurrence of SCRA adulteration in a large set (n = 252) of herbal materials collected at an international dance festival. This did not reveal any positives, i.e. there were no samples that yielded a relevant CB1 activation. CONCLUSION: In summary, we established SCRA screening of herbal materials as a new application for the activity-based CB1 bioassay. The simplicity of the sample preparation, the rapid results and the universal character of the bioassay render it an effective and future-proof tool for evaluating herbal materials for the presence of SCRAs, which is relevant in the context of harm reduction.

The role of red and white light in optimizing growth and accumulation of plant specialized metabolites at two light intensities in medical cannabis (Cannabis sativa L.).

The cultivation of medical cannabis (Cannabis sativa L.) is expanding in controlled environments, driven by evolving governmental regulations for healthcare supply. Increasing inflorescence weight and plant specialized metabolite (PSM) concentrations is critical, alongside maintaining product consistency. Medical cannabis is grown under different spectra and photosynthetic photon flux densities (PPFD), the interaction between spectrum and PPFD on inflorescence weight and PSM attracts attention by both industrialists and scientists. Plants were grown in climate-controlled rooms without solar light, where four spectra were applied: two low-white spectra (7B-20G-73R/Narrow and 6B-19G-75R/2Peaks), and two high-white (15B-42G-43R/Narrow and 17B-40G-43R/Broad) spectra. The low-white spectra differed in red wavelength peaks (100% 660 nm, versus 50:50% of 640:660 nm), the high-white spectra differed in spectrum broadness. All four spectra were applied at 600 and 1200 µmol m-2 s-1. Irrespective of PPFD, white light with a dual red peak of 640 and 660 nm (6B-19G-75R/2Peaks) increased inflorescence weight, compared to white light with a single red peak of 660 nm (7B-20G-73R/Narrow) (tested at P = 0.1); this was associated with higher total plant dry matter production and a more open plant architecture, which likely enhanced light capture. At high PPFD, increasing white fraction and spectrum broadness (17B-40G-43R/Broad) produced similar inflorescence weights compared to white light with a dual red peak of 640 and 660 nm (6B-19G-75R/2Peaks). This was caused by an increase of both plant dry matter production and dry matter partitioning to the inflorescences. No spectrum or PPFD effects on cannabinoid concentrations were observed, although at high PPFD white light with a dual red peak of 640 and 660 nm (6B-19G-75R/2Peaks) increased terpenoid concentrations compared to the other spectra. At low PPFD, the combination of white light with 640 and 660 nm increased photosynthetic efficiency compared with white light with a single red peak of 660nm, indicating potential benefits in light use efficiency and promoting plant dry matter production. These results indicate that the interaction between spectrum and PPFD influences plant dry matter production. Dividing the light energy in the red waveband over both 640 and 660 nm equally shows potential in enhancing photosynthesis and plant dry matter production.

Prenatal tetrahydrocannabinol and cannabidiol exposure produce sex-specific pathophysiological phenotypes in the adolescent prefrontal cortex and hippocampus.

Clinical and preclinical evidence has demonstrated an increased risk for neuropsychiatric disorders following prenatal cannabinoid exposure. However, given the phytochemical complexity of cannabis, there is a need to understand how specific components of cannabis may contribute to these neurodevelopmental risks later in life. To investigate this, a rat model of prenatal cannabinoid exposure was utilized to examine the impacts of specific cannabis constituents (Δ9-tetrahydrocannabinol [THC]; cannabidiol [CBD]) alone and in combination on future neuropsychiatric liability in male and female offspring. Prenatal THC and CBD exposure were associated with low birth weight. At adolescence, offspring displayed sex-specific behavioural changes in anxiety, temporal order and social cognition, and sensorimotor gating. These phenotypes were associated with sex and treatment-specific neuronal and gene transcriptional alterations in the prefrontal cortex, and ventral hippocampus, regions where the endocannabinoid system is implicated in affective and cognitive development. Electrophysiology and RT-qPCR analysis in these regions implicated dysregulation of the endocannabinoid system and balance of excitatory and inhibitory signalling in the developmental consequences of prenatal cannabinoids. These findings reveal critical insights into how specific cannabinoids can differentially impact the developing fetal brains of males and females to enhance subsequent neuropsychiatric risk.

Significant Psychedelic Experiences Evaluated for Mystical Characteristics Associated with Cannabis Use Reduction and Psychological Flexibility Improvement: A Naturalistic Cross-Sectional Retrospective Survey.

Treating cannabis use disorder remains a significant challenge in the field of addiction medicine. Some recent studies point to psychedelic-assisted psychotherapy as a potential treatment option for substance use disorders. The objective of this study was therefore to explore the impact of naturalistic psychedelic experiences on cannabis use and psychological flexibility. An online retrospective survey was carried out on 152 cannabis users who also reported a significant experience induced by psychedelics in the past. Following a psychedelic experience, there was a significant and sustained reduction of average CUDIT score (p < .001), frequency of cannabis use (p < .001), and acute duration of daily intoxication (p < .001). Cannabis use reduction during the first month post-experience was significantly associated with the intensity of the mystical experience (p = .01). Participants reported a concomitant increased lasting improvement of psychological flexibility following the experience (p < .001), which was correlated to the intensity of the mystical experience during the first month post-experience (p = .04). This study demonstrates that naturalistic psychedelic experiences may be followed by a decrease in cannabis use. Positive health outcomes appear potentially connected to the intensity of the mystical experience, as well as an improvement in psychological flexibility.

Lebanese cannabis oil as a potential treatment for acute myeloid leukemia: In vitro and in vivo evaluations.

ETHNOPHARMACOLOGICAL RELEVANCE: The Cannabis sativa L. ssp. indica (Lam.) plant has been historically utilized as a natural herbal remedy for the treatment of several ailments. In Lebanon, cannabis extracts have long been traditionally used to treat arthritis, diabetes, and cancer. AIM OF THE STUDY: The current study aims to investigate the anti-cancer properties of Lebanese cannabis oil extract (COE) on acute myeloid leukemia using WEHI-3 cells, and a WEHI-3-induced leukemia mouse model. MATERIALS AND METHODS: WEHI-3 cells were treated with increasing concentrations of COE to determine the IC50 after 24, 48 and 72-h post treatment. Flow cytometry was utilized to identify the mode of cell death. Western blot assay was performed to assess apoptotic marker proteins. In vivo model was established by inoculating WEHI-3 cells in BALB/c mice, and treatment commencing 10 days post-inoculation and continued for a duration of 3 weeks. RESULTS: COE exhibited significant cytotoxicity with IC50 of 7.76, 3.82, and 3.34 µg/mL at 24, 48, and 72 h respectively post-treatment. COE treatment caused an induction of apoptosis through an inhibition of the MAPK/ERK pathway and triggering a caspase-dependent apoptosis via the extrinsic and intrinsic modes independent of ROS production. Animals treated with COE exhibited a significantly higher survival rate, reduction in spleen weight as well as white blood cells count. CONCLUSION: COE exhibited a potent anti-cancer activity against AML cells, both in vitro and in vivo. These findings emphasize the potential application of COE as a chemotherapeutic adjuvant in treatment of acute myeloid leukemia.

Predictors of changes in marijuana consumption in Germany during the covid-19 pandemic.

During the Covid-19 pandemic Germany experienced its first increase in the proportion of heavy cannabis users since 1995. With the expected nationwide decriminalization of cannabis before 2025, we investigate the potential causes for that increase. Data were from the 2021 European Web Survey on Drugs (EWSD) including 762 12-month marijuana users from Germany (72.9% male, mean age = 29.5 years). Both heavy and regular cannabis consumers reported an increase in marijuana consumption during the pandemic, with infrequent users reporting a decrease. Using multinomial logistic regression, we found younger individuals (OR = 0.95 [95% CI = 0.92, 0.98]) and those not pursuing or completing higher education (OR = 1.86 [1.23, 2.81]) had increased use. Additionally, using cannabis to self-medicate (OR = 2.79 [1.56, 4.99]) and purchasing marijuana (OR = 2.26 [1.35, 3.77]) was associated with increased use. We found, relative to infrequent users, both regular (OR = 4.00 [2.39, 6.72]) and notably heavy users (OR = 31.17 [12.10, 80.32]) were more likely to use cannabis to self-medicate. Both regular (OR = 4.09 [2.47, 6.77]) and especially heavy users (OR = 13.53 [6.74, 27.16]) were also more likely to purchase marijuana. Heavy users were also more likely to be past 30-day tobacco users (OR = 5.92 [2.81, 12.45]). We identified the self-reported motivation of using cannabis to self-medicate as well as act of purchasing marijuana as having the strongest relation to being a heavy user and increasing marijuana use during the Covid-19 pandemic.

Examining the association between prenatal cannabis exposure and child autism traits: A multi-cohort investigation in the environmental influences on child health outcome program.

This study examined the association between prenatal cannabis exposure and autism spectrum disorder (ASD) diagnoses and traits. A total sample of 11,570 children (ages 1-18; 53% male; 25% Hispanic; 60% White) from 34 cohorts of the National Institutes of Health-funded environmental influences on child health outcomes consortium were included in analyses. Results from generalized linear mixed models replicated previous studies showing that associations between prenatal cannabis exposure and ASD traits in children are not significant when controlling for relevant covariates, particularly tobacco exposure. Child biological sex did not moderate the association between prenatal cannabis exposure and ASD. In a large sample and measuring ASD traits continuously, there was no evidence that prenatal cannabis exposure increases the risk for ASD. This work helps to clarify previous mixed findings by addressing concerns about statistical power and ASD measurement.

Understanding the epidemiology and perceived efficacy of cannabis use in patients with chronic musculoskeletal pain.

BACKGROUND: The belief that cannabis has analgesic and anti-inflammatory properties continues to attract patients with chronic musculoskeletal (MSK) pain towards its use. However, the role that cannabis will play in the management of chronic MSK pain remains to be determined. This study examined 1) the rate, patterns of use, and self-reported efficacy of cannabis use among patients with chronic MSK pain and 2) the interest and potential barriers to cannabis use among patients with chronic MSK pain not currently using cannabis. METHODS: Self-reported cannabis use and perceived efficacy were prospectively collected from chronic MSK pain patients presenting to the Orthopaedic Clinic at the University Health Network, Toronto, Canada. The primary dependent variable was current or past use of cannabis to manage chronic MSK pain; bivariate and multivariable logistic regression were used to identify patient characteristics independently associated with this outcome. Secondary outcomes were summarized descriptively, including self-perceived efficacy among cannabis users, and interest as well as barriers to cannabis use among cannabis non-users. RESULTS: The sample included 629 patients presenting with chronic MSK pain (mean age: 56±15.7 years; 56% female). Overall, 144 (23%) reported past or present cannabis use to manage their MSK pain, with 63.7% perceiving cannabis as very or somewhat effective and 26.6% considering it as slightly effective. The strongest predictor of cannabis use in this study population was a history of recreational cannabis use (OR 12.7, p<0.001). Among cannabis non-users (N=489), 65% expressed interest in using cannabis to manage their chronic MSK pain, but common barriers to use included lack of knowledge regarding access, use and evidence, and stigma. CONCLUSIONS: One in five patients presenting to an orthopaedic surgeon with chronic MSK pain are using or have used cannabis with the specific intent to manage their pain, and most report it to be effective. Among non-users, two-thirds reported an interest in using cannabis to manage their MSK pain, but common barriers to use existed. Future double-blind placebo-controlled trials are required to understand if this reported efficacy is accurate, and what role, if any, cannabis may play in the management of chronic MSK pain.

Investigating Substance Use as a Coping Strategy Among Adolescent Psychiatric Inpatients: A Comparative Analysis Before and During the COVID-19 Pandemic.

The COVID-19 pandemic resulted in significant changes in daily life, potentially impacting mental health and substance use behavior. Research on COVID-related changes in adolescent substance use have yielded mixed findings. The current cross-sectional chart review study compared rates of past-year substance use before and during COVID-19 among adolescent psychiatric inpatients, and investigated how motives for coping with COVID-19 changes were related to psychiatric acuity, and past-year substance use. Count models assessed if the number of past-year days of alcohol and cannabis use was higher among adolescents (n = 491, 11-18 years, 61% female) hospitalized during COVID-19 (3/14/20 to 4/5/21) versus adolescents hospitalized before COVID-19 (8/30/2019 to 3/13/20). For a subsample of COVID-19 inpatients (n = 124; 75% female), we evaluated psychiatric correlates of endorsing substances to cope with COVID-19 changes/rules. Results indicated adolescents admitted during COVID-19 reported significantly more past-year alcohol and cannabis use days than adolescents admitted before COVID-19. Adolescents endorsed using alcohol (19%), cannabis (33%), and e-cigarettes/vaping (25%) to cope with COVID-19. E-cigarette/vaping to cope with COVID-19 was significantly related to lifetime suicide attempt. Endorsing alcohol or cannabis to cope with COVID-19 was associated with a significantly greater number of past-year use days for each respective substance. Adolescent psychiatric inpatients admitted during COVID-19 reported more substance use days than adolescents admitted before COVID-19. Using substances to cope was linked to psychiatric correlates (e.g., suicidality). Assessing the presence and function of substance use in this population may be important to identify, treat, and prevent compounding negative outcomes during times of community stress.

Prenatal tobacco and tobacco-cannabis co-exposure: Relationship with attention and memory in middle childhood.

We examined associations between prenatal tobacco exposure (with and without cannabis exposure) and children's performance on laboratory measures of sustained attention, attentional set shifting, and working memory in middle childhood (9-12 years of child age). Participants were recruited in the first trimester of pregnancy and oversampled for prenatal tobacco exposure; with a smaller sample (n = 133; n = 34 non-substance exposed, n = 37 exposed to tobacco only, n = 62 co-exposed) invited (oversampled for co-exposure) to participate in the middle-childhood assessment (M age = 10.6, SD = 0.77; 68% Black, 20% Hispanic). Results for sustained attention indicated lower attention (percent hits) at the first epoch for tobacco only exposed compared to non-exposed and co-exposed; a trend (p = .07) towards increases in impulsive responding across time (a total of 8 epochs) for tobacco exposed (with and without cannabis) compared to non-exposed children; and a significant association between higher number of cigarettes in the first trimester and greater increases in impulsive responding across epochs. However, children prenatally exposed to tobacco (with and without cannabis) demonstrated greater short-term memory compared to children not prenatally exposed, and this difference was driven by higher scores for children prenatally co-exposed to tobacco and cannabis compared to those who were non-exposed. Overall, results suggest that prenatal tobacco exposure, especially in the first trimester, may increase risk for impulsive responding on tasks requiring sustained attention, and that co-use of cannabis did not exacerbate these associations. The higher short-term memory scores among children who were co-exposed compared to non-exposed are perplexing and need replication, particularly in studies with larger sample sizes and samples exposed only to cannabis to examine this more closely.

NHS-Reimbursed Cannabis Flowers for Cancer Palliative Care and the Management of Chemotherapy-Induced Nausea and Vomiting: An Autobiographical Case Report.

Chemotherapy-induced nausea and vomiting (CINV) is a debilitating side effect of cancer treatment, affecting many patients. Cannabinoid agonists, such as nabilone and Δ9-tetrahydrocannabinol (THC), the main psychoactive component of Cannabis sativa L., have shown efficacy as antiemetics. Here, we report the case of Michael Roberts (MR), who we believe is the first British patient reimbursed by the National Health Service (NHS) England for the cost of medicinal cannabis flowers to manage CINV. Medical data were obtained from NHS records and individual funding request (IFR) forms. Patient-reported outcome measures (PROMs) were collected using validated questionnaires as part of the standard of care at the specialized private clinics where the prescription of medicinal cannabis was initiated. The patient presented with rectosigmoid adenocarcinoma with lung metastases. He received FOLFIRI (folinic acid, fluorouracil, and irinotecan) chemotherapy and underwent an emergency Hartmann's procedure with subsequent second-line FOLFOX (folinic acid, fluorouracil, and oxaliplatin) chemotherapy and lung ablation. MR reported severe nausea and vomiting associated with the initial FOLFIRI treatment. Antiemetics metoclopramide and aprepitant demonstrated moderated efficacy. Antiemetics ondansetron, levomepromazine, and nabilone were associated with intolerable side effects. Inhalation of THC-predominant cannabis flowers in association with standard medication improved CINV, anxiety, sleep quality, appetite, overall mood, and quality of life. Our results add to the available evidence suggesting that medicinal cannabis flowers may offer valuable support in cancer palliative care integrated with standard-of-care oncology treatment. The successful individual funding request in this case demonstrates a pathway for other patients to gain access to these treatments, advocating for broader awareness and integration of cannabis-based medicinal products in national healthcare services.

Association Between Preoperative Cannabis Use and Increased Rate of Revision Surgery Following Spinal Fusion: A Systematic Review and Meta-Analysis.

The use of cannabis as a method of chronic pain relief has skyrocketed since its legalization in states across the United States. Clinicians currently have a limited scope regarding the effectiveness of marijuana on surgical procedures. This systematic review aims to determine the effect of current cannabis use on the rate of failure of spinal fusions and overall surgical outcomes. A systematic review was performed in accordance with the Preferred Reporting Items for Systematic Review and Meta-Analyses (PRISMA) statement. PubMed, Embase, and Scopus were searched, identifying studies assessing spinal fusion with reported preoperative cannabis use. Outcomes of interest included reoperation due to fusion failure or pseudoarthrosis with a follow-up time of at least six months. Subgroups of cervical fusions alone and lumbar fusions alone were also analyzed. Certainty in evidence and bias was assessed using the GRADE criteria and ROBINS-I tool (PROSPERO #CRD42023463548). Four studies met the inclusion criteria, with a total of 788 patients (188 in the cannabis user group and 600 in the non-user group). The rate of revision surgery among cannabis users was higher than that in non-users for all spinal fusions (RR: 3.58, 95% CI: 1.67 to 7.66, p = 0.001). For cervical fusions alone, there remained a higher rate of revision surgery for cannabis users compared to non-users (RR: 4.47, 95% CI: 1.93 to 10.36, p = 0.0005). For lumbar fusions alone, there was no difference in the rates of revision surgery between cannabis users and non-users (RR: 1.21, 95% CI: 0.28 to 7.73, p = 0.79). Cannabis use was shown to be associated with a higher rate of pseudoarthrosis revisions in spinal fusions on meta-analysis. On subgroup stratification by spine region, cannabis use remained associated with pseudoarthrosis revisions on cervical fusions alone but not lumbar fusions alone. Further research with larger, randomized studies is required to fully elucidate the relationship between cannabis use and fusion, both in general and by spinal region.

Expectations of How Acute Cannabis Use Affects Gambling Experiences and Behaviors.

Emerging research shows that many individuals commonly consume cannabis while gambling. However, individuals' expectations for how cannabis consumption will impact their gambling behavior remain unknown. Participants who gambled weekly (N = 472) were recruited from Amazon Mechanical Turk and completed assessments of gambling behaviors, cannabis consumption, and expectations about the influence of cannabis on gambling. Almost all participants (94%) screened positive for problem gambling. Over half of participants (55%) reported lifetime cannabis consumption, and almost all those participants (99%) reported gambling under the influence of cannabis (GUIC) in the past month. Most participants agreed with positive expectations of gambling; they expected that they would feel calmer when under the influence of cannabis (61.4%), that gambling would be more enjoyable (61.0%), and that their gambling skills would increase when GUIC (60.6%). At the same time, most participants also agreed with negative expectations of GUIC. They expected cannabis use would make them more careless (56.4%), more anxious (54.8%), and less able to concentrate (53.7%) while gambling. Negative cannabis expectancies were significantly associated with the severity of cannabis consumption. Both positive and negative cannabis expectancies were significantly associated with gambling problems and time spent gambling under the influence of cannabis. These findings indicate that expectations may influence the decision to consume cannabis and gamble simultaneously. This study contributes to the need for addressing cannabis expectations during treatment of gambling problems.

Changes in Parent-Student Text Message and Phone Call Communication During the Transition to College as Predictors of Cannabis and Simultaneous Use During the First Year.

Parent communication can be protective against cannabis use among young adults. However, changes in parent-student communication frequency naturally occur during the transition from high school to college. Recent research suggests declines in parent-student communication frequency predict increased drinking and consequences during the first year of college, yet these effects on other risky behaviors are unknown. The current study investigated whether post-matriculation changes in frequency of texting/calling with parents predict cannabis use and simultaneous use of cannabis and alcohol, and whether pre-matriculation cannabis and simultaneous use predict changes in communication. First-year students (N = 287, 61.3% female, 50.9% White) reported cannabis and simultaneous use pre- and post-matriculation (T1 & T3) and changes in frequency of texting/calling their mother/father per day (T2). Negative binomial hurdle models examined whether T2 changes in communication frequency predicted T3 cannabis and simultaneous use, and logistic regression models examined whether T1 cannabis and simultaneous use predicted T2 changes in communication frequency. Results revealed that increasing (vs. decreasing) frequency of calling with mothers and texting with fathers was protective against cannabis use, whereas increasing frequency of calling with fathers was associated with greater risk of use. Changes in communication did not significantly predict simultaneous use, nor did pre-matriculation cannabis or simultaneous use predict changes in either mode of communication with parents during the college transition. These findings highlight that changes in mother and father communication may be both beneficial and detrimental to cannabis use depending on the parent and mode of communication. Implications for these findings are discussed.

Impact of Legalization on Cannabis Use, Attitudes, and Purchasing Preferences: A Repeated Cross-Sectional Survey of Canadian Young Adults.

Objective: The Government of Canada legalized recreational cannabis use in October of 2018 with the implementation of the Cannabis Act. The act aimed to reduce the illicit cannabis market, improve consumer health outcomes, and reduce youth access to cannabis. However, little is known about the attitudes and behaviors of young adults, who have been shown to have a high prevalence of cannabis use, towards cannabis after legalization. Method: In this descriptive study, we examined cannabis use, attitudes, and purchasing preferences among Canadian university-attending young adults both before and after the legalization of cannabis. Participants were recruited from a large Canadian university from 2017 to 2021. Results: Our findings showed that there was an increase in cannabis use immediately following legalization that subsequently decreased in later years. Additionally, attitudes about the legalization of cannabis became more favorable in later years (following legalization), particularly among those who did not use cannabis. Most young adults were also keen to purchase cannabis from a government-owned store before legalization. However, with the exception of past-month consumers, this preference decreased substantially following legalization. Conclusions: The current research adds to the knowledge base about changes in cannabis-related attitudes and use after legalization and focuses on a key population - young adults.