Preventing cannabis-related harm: Considerations for youth and beyond

Transcription

1 Preventing cannabis-related harm: Considerations for youth and beyond Elaine Hyshka, BA, MA, PhD Assistant Professor, School of Public Health, University of Alberta; Scientific Director, Inner City Health and Wellness Program, Royal Alexandra Hospital Cannabis legalization in Canada: Implications for public health in Alberta May ; University of Calgary, Calgary, Canada

2 Outline Brief overview of cannabis-related harms Historical approaches to preventing cannabis-related harm Primary prevention 2.0 Harm reduction strategies Conclusion

3 Cannabis-related harms Brief overview

4 Age of onset Most people who use cannabis do so infrequently; and without significant negative health or social outcomes Most use concentrated amongst young people and youth, and tapers off with age Initiating cannabis use in early adolescence increases risk of experiencing cannabis-related harm, longer cannabis-use trajectories, earlier transitions to problematic use

5 State of the evidence Conclusive evidence regarding the short- and long- term impacts of cannabis use remains elusive McCormick et al.; National Academies of Medicine (2017) Reviewed 10,000 studies; ranked evidence as insufficient (-), limited (+), moderate (++), substantial (+++), conclusive (++++)

6 Potential health risks Development of schizophrenia and other psychoses (+++) in those with genetic or biological liability Increased risk of motor vehicle crashes (+++) Low birth weight of offspring (+++) Respiratory symptoms (+++) with long term use Problematic use patterns and cannabis use disorder with early onset and/or heavy use (+++) Increased risk for males and those who use tobacco

7 Conventional approaches to preventing cannabis-related harm amongst youth

8 Prevention through criminal enforcement of abstinence Cannabis criminalized in Canada in 1923 Max. penalty for first conviction for possession of under 30 grams of cannabis is $1000 fine or 6 months in jail 55% of all cannabis-related possession cases involve single charge (StatCan, 2013) Hypothesis: Criminal penalties send a message to youth that deters them from using cannabis. with more severe penalties expected to have a stronger deterrent effect

9 Do criminal penalties impact youth cannabis use? EMCDDA (2017). Cannabis legislation in Europe an overview.

10 Adolescent use rates, post-legalization Available data includes two large state surveys from Washington and Colorado, which demonstrate that teen cannabis use rates have remained stable post-legalization Healthy Kids Colorado Survey (2015).

11 Diverts resources from prevention, treatment, and harm reduction Source: DeBeck K, Wood E, Montaner J, Kerr T. Canada s new federal National Anti-Drug Strategy : An informal audit of reported funding allocation. International Journal of Drug Policy Mar;20(2):

12 Iatrogenic impacts of criminalization Differential enforcement Lifelong impacts of criminalization Discourages help-seeking Organized crime and drug market violence Clandestine production, potentially unsafe or contaminated supply Prohibits effective population surveillance and screening for high risk cannabis use

13 Universal prevention through individuallevel risk reduction Prevention campaigns that aim to promote abstinence by increasing knowledge or personal skills Settings: Schools, communities Providers: Mass (and social) media, classroom teachers, law enforcement, peer leaders Tactics: Public service announcements Social (drug) resistance skills Personal and social skills training Normative education

14 Universal prevention review of reviews Review Focus Parameters Included studies Conclusions Community-based interventions Ferri (2013) Effectiveness of mass media campaigns aimed at reducing illicit drug use Earliest studies reported in 28 articles No evidence of effectiveness or iatrogenic impacts on drug use. Werb et al. (2011) Effectiveness of public service announcements aimed at reducing illicit drug use Earliest RCTs, 4 observational studies No evidence of effectiveness on substance use. Thomas et al. (2011) Effectiveness of mentoring on substance use among deprived youth Earliest cluster RCTs No evidence of effectiveness on drug use, substance use; mixed evidence of effectiveness on alcohol use. Gates et al. (2006) Drug use prevention in non-school settings Earliest cluster RCTs Positive effect of brief interventions and motivational interviewing; no evidence of effectiveness for educational and skills training. [Slide via from Cam Wild ]

15 Universal prevention review of reviews Review Focus Parameters Included studies Conclusions School-based interventions Teeson et al. (2012) Lemstra et al. (2010) Porath-Waller et al. (2010) Foxcroft (2011) Faggiano et al. (2008) Alcohol and other drug use prevention Cannabis and alcohol use prevention Cannabis use prevention Universal alcohol use prevention Illicit drug use prevention Earliest RCTs of 7 Australian programs RCT and cohort studies experimental and quasi-experimental studies (NB: no assessment of study quality) Positive impact for alcohol programs; no evidence of effectiveness for other drug programs Positive impact of comprehensive interventions; no evidence of effectiveness of knowledge only interventions on alcohol and of longer program duration Overall positive impact on cannabis use. Interactive interventions more successful than didactic approaches.. Poorer outcomes for teacher-led interventions; better outcomes with increasing number of sessions. Earliest RCTs Inconclusive evidence of positive impact for alcohol-specific and generic substance use programs. No evidence of effectiveness of generic education. Earliest (29 RCTs, 3 controlled prospective studies) No evidence of effectiveness for knowledgebased interventions. Positive impact for skills-based interventions. [Slide via from Cam Wild ]

16 Time to rethink universal prevention Most common factors that reduce program effectiveness: 1. Implementation failure Low fidelity to program elements known via research to improve odds of success. Contracting development of creative materials used in programs to marketing and PR firms that are poorly informed by or responsive to scientific evidence. 2. Overemphasis on abstinence as the outcome of interest. Not allowing for a distinction between safer/appropriate use and problematic use BC research with street-involved youth suggests that they want factual information about drug use, resources and supports, counseling, harm reduction (Ti et al., 2017) 3. Overemphasis on individual-level interventions and proximate risk factors Attempt to change personal characteristics with far less attention paid to environmental influences that shape behaviour

17 Time to rethink universal prevention 1. Most commonly-used approach (DARE and offshoots) shown conclusively to have no or iatrogenic effects (Foxcroft et al., 2011; Sloboda et al., 2009) Yet infrastructure for/interest in this program lives on 2. Community-based settings: No evidence of effectiveness for mass media campaigns as currently implemented Out of school youth: brief interventions/motivational interviewing show positive effects; no evidence for general knowledge and skills training 3. School settings: No evidence for effectiveness of passive, knowledge-based informational approaches Individual-skills based approaches show moderate positive impacts if they are interactive, include multiple sessions, and are not delivered by police Comprehensive approaches promising

18 Promising approaches for preventing cannabis-related harm amongst youth

19 Public health approach to youth cannabis use Focus is not on preventing all use or promoting abstinenceonly. Instead aim is to: Prevent initiation of cannabis use in (early) adolescence Prevent related harms amongst adolescents and young adults who initiate use.

20 Substance use is a social phenomenon Adolescent substance use not just a product of deficits in individual knowledge or skills Influenced by multi-level risk and protective factors. Difficult to change behaviour without influencing environmental factors Effective prevention programs Target multiple risk and protective factors Intervene at more than one social ecological level Often have a broader focus than just drugs or alcohol

21 Domains of social influence - peers Evidence indicates that peer networks are a strong determinant of early initiation and current use of cannabis Cannabis use is seen as a situated product, not so much of pressure, but of active lifestyle decisions in keeping with group norms within social contexts of constraint and opportunity (Rhodes et al., 2003, p. 316)

22 Domains of social influence - family Structure and quality of family life predicts early initiation into cannabis use Operationalized in a variety of ways, however, lack of parental monitoring is particular a particularly important risk factor for early adolescent cannabis use (Eitle, 2005; Kosterman et al., 2000; Tang & Orwin, 2009).

23 Prevention 2.0 Several examples of successful prevention interventions which intervene at broader socio-ecological levels The Gatehouse Project (Australia) Strengthening Families Program (US) Icelandic Model of Adolescent Substance Use Prevention (Sigfúsdóttir et al. 2009): Interventions to strengthen parent-child attachment and engage adolescents in family life and alternative leisure activities Targeted interpersonal, school, community, and policy level

24 Percentage of self-reported substance use among Icelandic adolescents, by year, between 1997 and 2007 Source: Sigfúsdóttir ID, Thorlindsson T, Kristjánsson ÁL, Roe KM, Allegrante JP. Substance use prevention for adolescents: the Icelandic Model. Health Promot Int Mar 1;24(1):

25 Harm reduction strategies for youth who use cannabis Even with widespread implementation of the more promising substance use prevention interventions, it is likely that some adolescents will continue to initiate cannabis use, and use throughout high school (Midford, 2009) Youth-focused programming is needed to reduce harms for current users However, very little research has addressed cannabis harm reduction strategies for adults or youth Experiences with other substances instructive

26 School-based harm reduction programming for older adolescents Poulin and Nicholson (2005) Demonstration project in Nova Scotia Targeted school and interpersonal levels Aimed to reduce risky patterns of substance use amongst high school age population harm minimization was an acceptable approach to drug education targeting the senior high school population some evidence of effectiveness

27 Conclusion Moving away from conventional approaches to preventing cannabisrelated harm is consistent with a public health approach to psychoactive substance use New approaches require high quality surveillance data to be effective Reimagining universal prevention and development of harm reduction programs targeting older adolescents could have ancillary benefits for other risk behaviours or substances

28 Thank you Contact:

29 References Champion, K.E., Newton, N.C., Barrett, E.L., & Teeson, M. (2013). A systematic review of school-based alcohol and other drug prevention programs facilitated by computers or the internet. Drug and Alcohol Review, 32, Emmers, E., Bekkering, G.E., & Hannes, K. (2015). Prevention of alcohol and drug misuse in adolescents: An overview of systematic reviews. Nordic Studies on Alcohol and Drugs, 32, Faggiano, F., Vigna-Taglianti, F. D., Versino, E., Zambon, A., Borraccino, A., & Lemma, P. (2008). School-based prevention for illicit drugs use: A systematic review. Preventive Medicine, 46, Ferri M, Allara E, Bo A, Gasparrini A, Faggiano F (2013). Media campaigns for the prevention of illicit drug use in young people. Cochrane Database of Systematic Reviews, Issue 6. Art. No.: CD DOI: / CD pub2. Foxcroft, D. R., & Tsertsvadze, A. (2011). Universal school-based prevention programs for alcohol misuse in young people. Cochrane Database Systematic Reviews, 5, CD Gates, S., McCambridge, J., Smith, L. A., & Foxcroft, D. R. (2006). Interventions for prevention of drug use by young people delivered in non-school settings. Cochrane Database Systematic Reviews, 1, CD Lemstra, M., Bennett, N., Nannapaneni, U., Neudorf, C., Warren, L., Kershaw, T., & Scott, C. (2010). A systematic review of school-based marijuana and alcohol prevention programs targeting adolescents aged Addiction Research and Theory, 18, Porath-Waller, A.J., Beasley, E., & Bierness, D.J. (2010). A meta-analytic review of school-based prevention for cannabis use. Health Education Research, 22, ,

30 Lower Risk Cannabis Use Guidelines Although abstinence is the only way to completely avoid the health risks of cannabis use, for those who do use it, the risks are expected to be reduced if: use is delayed until early adulthood frequent use is avoided users shift away from smoking cannabis towards less harmful (smokeless) delivery systems such as vaporizers less potent products are used, or THC dose is titrated driving is avoided for 3 to 4 hours after use, or longer if needed people with higher risk of cannabis related problems (e.g. people with a personal or family history of psychosis, people with cardiovascular problems, and pregnant women) abstain altogether. Centre for Addiction and Mental Health (2014): CANNABIS POLICY FRAMEWORK

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