Swipe to Inhale: Tobacco-Related Content on Social Media and Susceptibility to Tobacco Use.

INTRODUCTION: Research has linked youth exposure and engagement with tobacco-related content on social media to behavioral changes; however, there is a lack of studies exploring the source and types of such content and their impact on youth's susceptibility to tobacco use. This study examined the association between the type and source of content posted on social media and susceptibility to tobacco use, defined as curiosity or intention to use tobacco or e-cigarettes. METHODS: Data were from the Population Assessment Tobacco and Health study, a nationally representative cohort study of U.S. youth (n=5,652). This analysis conducted in March 2024, focused on Wave 6 (2021), examining youth who used social media in the past month and did not use cigarettes or e-cigarettes. Multivariable logistic regression was performed to evaluate the associations. RESULTS: Of the youth who had used social media in the past month (88.7%), 61.4% had encountered tobacco-related content. Exposure to such content was associated with greater susceptibility to e-cigarette use (OR=1.49, 95% CI: 1.38-1.62) and cigarette use (OR=1.29, 95% CI: 1.17-1.43). Daily or near-daily exposure to tobacco-related content compared to non-exposed respondents was associated with greater odds of susceptibility to tobacco use (OR=1.53, 95% CI: 1.37-1.71). Only posts made by celebrities and influencers were associated with a greater susceptibility to tobacco use. CONCLUSIONS: Regular exposure to tobacco-related content on social media, particularly content shared by celebrities and social media influencers, was associated with susceptibility to tobacco use. These findings underscore the need for targeted interventions to mitigate the effects of social media influencers on youth.

Therapeutic Potential of Psychedelic Drugs: Navigating High Hopes, Strong Claims, Weak Evidence, and Big Money.

Therapeutic claims about many psychedelic drugs have not been evaluated in any studies of even modest rigor. The science of psychedelic drugs is strengthening however, making it easier to differentiate some promising findings amid the hype that suffuses this research area. Ketamine has risks of adverse side effects (e.g., addiction and cystitis), but multiple studies suggest it can benefit individuals with treatment-resistant depression. Other therapeutic signals from psychedelic drug research that merit rigorous replication studies include 3,4-Methylenedioxymethamphetamine (MDMA) for post-traumatic stress disorder (PTSD) and psilocybin for depression, end of life dysphoria, and alcohol use disorder. The precise mechanisms through which psychedelic drugs can produce benefit and harm are not fully understood. Rigorous research is the best path forward for evaluating the therapeutic potential and mechanisms of psychedelic drugs. Policies governing the clinical use of these drugs should be informed by evidence and prioritize the protection of public health over the profit motive.

Surgical parameters influence paediatric knee kinematics and cartilage stresses in anterior cruciate ligament reconstruction: Navigating subject-specific variability using neuromusculoskeletal-finite element modelling analysis.

PURPOSE: Anterior cruciate ligament (ACL) rupture is increasingly common in paediatric and adolescent populations, typically requiring surgical ACL reconstruction (ACLR) to restore knee stability. However, ACLR substantially alters knee biomechanics (e.g., motion and tissue mechanics) placing the patient at elevated risk of early-onset knee osteoarthritis. METHODS: This study employed a linked neuromusculoskeletal (NMSK)-finite element (FE) model to determine effects of four critical ACLR surgical parameters (graft type, size, location and pre-tension) on tibial articular cartilage stresses in three paediatric knees of different sizes during walking. Optimal surgical combinations were defined by minimal kinematic and tibial cartilage stress deviations in comparison to a corresponding intact healthy knee, with substantial deviations defined by normalized root mean square error (nRMSE) > 10%. RESULTS: Results showed unique trends of principal stress deviations across knee sizes with small knee showing least deviation from intact knee, followed by large- and medium-sized knees. The nRMSE values for cartilage stresses displayed notable variability across different knees. Surgical combination yielding the highest nRMSE in comparison to the one with lowest nRMSE resulted in an increase of maximum principal stress on the medial tibial cartilage by 18.0%, 6.0% and 1.2% for small, medium and large knees, respectively. Similarly, there was an increase of maximum principal stress on lateral tibial cartilage by 11.2%, 4.1% and 12.7% for small, medium and large knees, respectively. Knee phenotype and NMSK factors contributed to deviations in knee kinematics and tibial cartilage stresses. Although optimal surgical configurations were found for each knee size, no generalizable trends emerged emphasizing the subject-specific nature of the knee and neuromuscular system. CONCLUSION: Study findings underscore subject-specific complexities in ACLR biomechanics, necessitating personalized surgical planning for effective restoration of native motion and tissue mechanics. Future research should expand investigations to include a broader spectrum of subject-specific factors to advance personalized surgical planning. LEVEL OF EVIDENCE: Level III.

The relationship between cannabis and nicotine use: A systematic review and meta-analysis.

BACKGROUND AND AIMS: Cannabis and nicotine (tobacco or e-cigarettes) use commonly co-occurs and understanding their relationship can help to inform public health strategies to prevent their harms. We conducted a systematic review and meta-analysis to estimate the association of cannabis use given prior nicotine use and vice versa. METHODS: PubMed, Embase, PsycINFO, Google Scholar and a hand-search were conducted in 2023 for longitudinal studies of the general population with no restrictions in settings (locations). Random-effects meta-analysis was conducted to estimate odds ratios between cannabis and nicotine use in both directions. The impact of unmeasured confounding was assessed using E-values. RESULTS: From 5387 identified records, we included 20 studies. Among cannabis-naïve youths, baseline use of any nicotine products was positively associated with initiation of any cannabis use at follow-up [odds ratio (OR) = 5.39, 95% confidence interval (CI) = 3.19, 9.11; adjusted OR (aOR) = 2.59, 95% CI = 2.01, 3.32]. In nicotine-naïve participants (youths + adults), baseline cannabis use was positively associated with the initiation of any nicotine use at follow-up (OR = 4.08, 95% CI = 2.05, 8.11; aOR = 2.94, 95% CI =1.54, 5.61). There were no significant associations between baseline cannabis use and subsequent initiation of any nicotine (aOR = 3.29, 95% CI = 0.85, 12.76) or daily nicotine use (aOR = 2.63, 95% CI = 0.41, 16.95) among youths. The median E-values were 5.5 for nicotine exposure and cannabis use initiation and 4.1 for cannabis exposure and nicotine use initiation, indicating that substantial unmeasured confounding would need to have a strong association with both outcomes to fully explain away the cannabis and nicotine relationship. CONCLUSION: Although the evidence for associations between cannabis use and tobacco use is mixed, a majority of studies to date have found that cannabis use is associated with prior nicotine use and vice versa.

Commentary: The Conflict Between Protecting Public Health and Raising Tax Revenue.

When Canada created a legal market for cannabis, it gave priority to public health by restricting marketing using branding and promotion via social and other media sources. These restrictions to protect the public from harmful use are under increasing pressure from the legal cannabis industry, which claims that they prevent them from outcompeting and replacing the illicit market. Public health advocates are reasonably concerned that these restrictions will not hold given our experience with alcohol, tobacco and gambling where governments' fiscal dependence on tax revenue favours the liberalization of regulation.

Will Australia's tightened prescription system reduce nicotine vaping among young people?

BACKGROUND: Australia introduced a prescription only policy for e-cigarettes in 2011 to prevent uptake among youth while allowing smokers to access e-cigarettes for cessation. This is one of the restrictive forms of regulation for e-cigarettes recommended by the World Health Organisation. AIMS: To assess whether the policy has prevented e-cigarette youth uptake and facilitated smokers' access to e-cigarettes for cessation; and to examine a proposed toughening of the policy. METHODS: An analysis of survey and administrative data on e-cigarette use and smoking and a critical analysis of the contents of submissions to parliamentary inquiries into the policy. RESULTS: E-cigarette use among youth and young adults has increased steeply since 2016 but very few of these products have been obtained through the prescription system, because medical authorities discourage their use. A policy change in 2021 to increase the prescription of e-cigarettes has not reduced e-cigarette use among youth and only marginally increased rates of prescribing. Australian policy makers have nonetheless tightened the prescription system by banning any use of e-cigarettes unless prescribed by a doctor and dispensed by a pharmacist. IMPLICATIONS: Australia's tightened prescription policy for e-cigarettes may reduce adolescent vaping but at the risk of reducing smokers' access to e-cigarettes and increasing the size of the illicit market for combustible cigarettes and e-cigarettes. A more effective policy would allow vapes to be sold as consumer products by licensed tobacconists under regulations that require prior product approval, plain packaging, bans on their promotion and enforced age restrictions on purchases.

Restricting supply of tobacco products to pharmacies: a scoping review.

OBJECTIVE: We synthesised the published literature on proposals to restrict tobacco supply to pharmacies, covering (1) policy concept/rationale/attempts, (2) policy impact and implementation and (3) policy and research recommendations. DATA SOURCES: We searched eight databases (PubMed, CINAHL, Scopus, Web of Science, Embase, IPA, ProQuest and OATD) for publications with at least an English-language abstract. We searched reference lists of included publications manually. STUDY SELECTION: One author screened all publications, and a second author reviewed a 10% subset. We focused on approaches to restrict the supply of tobacco products to pharmacies, without any restrictions on study design, location, participants or publication date. DATA EXTRACTION: Data extraction adhered to the JBI Scoping Review Methodology and Preferred Reporting Items for Systematic Reviews and Meta-Analyses extension for Scoping Reviews checklist. DATA SYNTHESIS: We included 18 publications. Among the 13 studies conducted in specific geographical contexts, 8 were from Aotearoa/New Zealand. Most publications (n=8) focused on effectiveness domains, indicating potential reductions in retailer density, smoking prevalence, disease burden, cost and increased opportunities for cessation advice. Seven explored policy acceptability among experts, pharmacists and people who smoke. Publications noted that pharmacy-only supply aligns with other programmes involving pharmacists, such as needle exchange programmes, but conflicts with efforts to phase out tobacco sales from the US and Canadian pharmacies. CONCLUSIONS: Progress in tobacco retailing policy (eg, licensing, retailer incentives) and research (eg, assessment of policy equity and durability, application in other geographical contexts) are needed before a pharmacy-only tobacco supply model would be feasible.

E-cigarettes: A framework for comparative history and policy.

BACKGROUND: England, Australia and the United States have approached the regulation of e-cigarettes in very different ways, yet all three countries have appealed to the concept of evidence as underpinning policy responses. We compared these policy responses using a combination of the methodologies of historians and policy scientists in order to elucidate the factors that had influenced policy in each country. ARGUMENT/ANALYSIS: Each country's evidence and values intersected in different ways, producing very different responses within specific national contexts and histories. Our analysis accordingly emphasized the historical precursors of the policy issues raised by e-cigarettes and placed the policy debate within the context of regulatory bodies and the networks of researchers and advocates who influenced policy. Issues also of importance were the nature of the state; political context; the pre-history of nicotine for smoking cessation; the role of activism and its links with government; the influence of harm reduction ideas from drugs and HIV; and finally, whom policy was perceived to benefit. In the United Kingdom, based on this pre-history of the smoking issue, it was the existing smoker, while in the United States and Australia, protecting children and adolescents has played a central role. CONCLUSIONS: Structural and historical factors appear to underpin differences in e-cigarette policy development in England, Australia and the United States.

Sensitivity analysis of paediatric knee kinematics to the graft surgical parameters during anterior cruciate ligament reconstruction: A sequentially linked neuromusculoskeletal-finite element analysis.

BACKGROUND AND OBJECTIVE: Incidence of paediatric anterior cruciate ligament (ACL) rupture has increased substantially over recent decades. Following ACL rupture, ACL reconstruction (ACLR) surgery is typically performed to restore passive knee stability. This surgery involves replacing the failed ACL with a graft, however, surgeons must select from range of surgical parameters (e.g., type, size, insertion, and pre-tension) with no robust evidence guiding these decisions. This study presents a systemmatic computational approach to study effects of surgical parameter variation on kinematics of paediatric knees. METHODS: This study used sequentially-linked neuromusculoskeletal (NMSK) finite element (FE) models of three paediatric knees to estimate the: (i) sensitivity of post-operative knee kinematics to four surgical parameters (type, size, insertion, and pre-tension) through multi-input multi-output sensitivity analysis; (ii) influence of motion and loading conditions throughout stance phase of walking gait on sensitivity indices; and (iii) influence of subject-specific anatomy (i.e., knee size) on sensitivivty indices. A previously validated FE model of the intact knee for each subject served as a reference against which ACLR knee kinematics were compared. RESULTS: Sensitivity analyses revealed significant influences of surgical parameters on ACLR knee kinematics, albeit without discernible trend favouring any one parameter. Graft size and pre-tension were primary drivers of variation in knee translations and rotations, however, their effects fluctuated across stance indicating motion and loading conditions affect system sensitivity to surgical parameters. Importantly, the sensitivity of knee kinematics to surgical parameter varied across subjects, indicating geometry (i.e., knee size) influenced system sensitivity. Notably, alterations in graft parameters yielded substantial effects on kinematics (normalized root-mean-square-error > 10 %) compared to intact knee models, indicating surgical parameters vary post-operative knee kinematics. CONCLUSIONS: Overall, this initial study highlights the importance of surgical parameter selection on post-operative kinematics in the paediatric ACLR knee, and provides evidence of the need for personalized surgical planning to ultimately enhance patient outcomes.

Participation in Australian drug treatment programs for individuals engaging in high-risk substance use: Data from a nationally representative sample.

INTRODUCTION: Substance use, including drugs, alcohol and smoking have a significant health, social and economic impact. We aim to assess the rate and factors associated with treatment access among individuals with high-risk substance use. METHOD: This study is a cross-sectional analysis of the 2019 Australian National Drug Strategy Household Survey (N = 22,015). Participants were persons with high-risk substance use based on the Alcohol, Smoking and Substance Involvement Screening Test-Lite (ASSIST-Lite) and current smokers. We measured self-reports of past 12-month engagement in a tobacco, alcohol or other drugs treatment program. RESULTS: Overall, 0.4% had high-risk drug use (0.3% cannabis, 0.1% meth/amphetamine or 0.1% opioids), 7.4% had high-risk alcohol use, and 14.0% currently smoked. Among high-risk users, past 12-month treatment access rates were 50.6% [22.3-78.9%] for opioids, 27.1% [8.1-46.1%] for meth/amphetamine, 14.5% [4.3-24.7%] for cannabis, 9.6% [8.1-11.0%] for alcohol and 11.7% [10.6-12.9%] for current smoking. The primary source of treatment support was information and education (12.7% drugs, 4.6% alcohol, 4.0% smoking), followed by counselling (6.7% drugs, 4.5% alcohol, 3.0% smoking). Online or internet support was accessed by 5.9% (drug) and 1.6% (alcohol) people with high-risk use. Psychological distress was associated with treatment access (drugs: odds ratio 3.03 [0.77-11.95], p = 0.111; alcohol: odds ratio 3.16 [2.20-4.56], p ≤ 0.001; smoking: odds ratio 1.95 [1.52-2.49], p ≤ 0.001). DISCUSSION AND CONCLUSIONS: The proportion of people engaging in risky substance use who had used treatment programs remains low, especially for alcohol. Public health strategies to scale up treatment access are warranted.

How much cannabis is used in a joint in Australia? An experimental investigation into use by potency and frequency.

INTRODUCTION: Cannabis use is highly prevalent in Australia, yet current survey metrics measure tetrahydrocannabinol (THC) exposure with limited accuracy. Often survey items measure cannabis quantity by assuming specific modes of use (i.e., 'how many joints do you use?'), which fail to capture variations in cannabis use and the diverse modes of use (e.g., joints, cones, spliffs). This study investigated how much cannabis is used in these modes of administration in an Australian sample. METHODS: Participants (N = 31, Mage = 25.77; 51% university students) completed the Roll a Joint Paradigm in which they rolled joints, spliffs and packed cones as they would typically, using oregano as 'cannabis.' Participants then prepared each again but with cannabis of higher or lower potency. RESULTS: The amount of cannabis used across different modes of administration was variable: joints (range 0.10-1.25 g), spliffs (range 0.12-1.21 g) and cones (range 0.03-0.41 g). Participants who used cannabis daily rolled three times the amount of cannabis into a joint. DISCUSSION AND CONCLUSIONS: The amount of cannabis used in common modes of administration may be highly variable. Daily use may be associated using larger quantities of cannabis. Titration attempts based on potency were not proportional or consistent across modes of administration. The results indicate people may adjust the quantity of cannabis based on perceived potency, however, not proportional to THC concentration. Inconsistency in the amount of cannabis used based on potency and within different modes of administration may represent a problem for self-report metrics which ask participants to report cannabis use in joints.

Prevalence and correlates of positive parental attitudes towards cannabis use and use intention in Australia during 2016 and 2019.

INTRODUCTION: With recent policy changes around medicinal cannabis in Australia, there is concern about the influence of changing norms of cannabis use on adults who are actively parenting. METHODS: This repeated cross-sectional population study used National and Drug Strategy and Household Surveys to estimate the changes and correlates of cannabis-related attitudes (support of legalisation, approve of regular use, would try or use if legal) among Australian parents from 2016 to 2019. RESULTS: The estimated proportion of parents who supported legalisation and approved regular cannabis use increased significantly. Parents who would try cannabis if it was legal grew from 5.9% (95 %CI: 5.2, 6.7) to 8.1% (95 %CI: 7.2, 9.0). Parents who said they would use cannabis more often increased from 1.6 (95 % CI: 1.2, 1.9) to 2.9 (95 %CI: 2.4, 3.4), an 81% jump in the three years. The strongest associations were observed between a very high level of psychological distress and regular smoking and drinking. For example, people with a very high level of psychological distress were 2.16 times (95 %CI: 1.42, 3.28) and 2.48 times (95 %CI: 1.61, 3.83) more likely to approve legalisation and regular cannabis use, respectively. Daily drinking was associated with higher odds of trying cannabis (OR = 1.66; CI: 1.25-2.20). DISCUSSION AND CONCLUSION: The proportion of parents who would try or use cannabis more often represents a sizeable pool of potential new and frequent users. This highlights the need for education and intervention strategies for parents who use cannabis and care for young children. The associations between mental health and substance use suggest that more research is needed to understand the impact of legalisation on vulnerable groups.

How has the brain disease model of addiction contributed to tobacco control?

Our paper evaluates the extent to which the brain disease model of addiction (BDMA) has contributed to reducing the prevalence of tobacco smoking and  tobacco-related harm over the past 20 years. We discuss the ways in which genetic and neuroscience research on nicotine addiction have contributed to our understanding of tobacco smoking. We then examine the extent to which the BDMA has produced more effective treatments to assist smoking cessation. We also assess the degree to which the BDMA has contributed to the tobacco control policies that have produced substantial reductions in tobacco-related morbidity and mortality in the two decades since the model was first proposed by Alan Leshner. We also assess whether the BDMA has reduced the stigmatisation of people who smoke tobacco.

Use of flavored cannabis vaping products in the US, Canada, Australia, and New Zealand: findings from the international cannabis policy study wave 4 (2021).

Background: Vaping is an increasingly popular mode of cannabis use. Few studies have characterized the role of flavors in cannabis e-liquids.Objectives: To explore the prevalence of flavored vaping liquids, including differences between countries and correlates of use.Methods: Data were from Wave 4 (2021) of the International Cannabis Policy Study with national samples aged 16-65 in Canada, the United States (US), Australia, and New Zealand. The sample comprised 52,938 respondents, including 6,265 who vaped cannabis e-liquids in the past 12-months (2,858 females, 3,407 males). Logistic regression models examined differences in the use of flavored e-liquids between countries and sociodemographic characteristics.Results: The prevalence of vaping cannabis e-liquids was highest in the US (15.3%) and Canada (10.7%) compared to Australia (4.0%) and New Zealand (3.7%). Among past 12-month cannabis consumers, 57.5% reported using flavored vaping liquids, 34.2% used unflavored vaping products and 8.3% did not know. People who vape in Australia were most likely to report using flavored liquids compared to New Zealand (OR = 2.29), Canada (OR = 3.14), and the US (OR = 3.14) (p < .05 for all). Fruit was the most reported vaping flavor (40.8%), followed by candy/dessert (20.4%) and vanilla (15.2%). Use of flavored vapes was greater among younger, ethnic minorities, female, higher education and income adequacy, and more frequent consumers (p < .05).Conclusion: Many cannabis consumers reported using flavored e-liquids, with highest levels among young people aged 16-35. Given the high prevalence of vaping in legal markets, regulators should consider the role of flavored vaping products in promoting cannabis use among this group.