Definitions of risky and problematic cannabis use: a systematic review Casajuana C, López-Pelayo H, Miquel L, Balcells MM, Colom J, Gual A

There is no conflict of interest related to this presentation

Introduction Cannabis the most used illicit drug worldwide Increasing evidence on organic, psychiatric and social consequences of consuming cannabis Early interventions in potential at-risk cannabis users are needed … but how can we identify this users? Cannabis is the third most consumed illicit drug worldwide and evidence for the negative consequences of cannabis consumption is increasing. Although cannabis is one of the oldest drugs used, little is known about which consumption patterns may lead to negative consequences. Cannabis dependence has been well documented, but pre-dependent stages remain unexplored

Knowledge gap Official definitions are lacking Risky cannabis use: pattern increasing the probability of future negative consequences Problematic cannabis use: pattern already causing negative consequences, with or without fullfilling dependence criteria Defintitionssitua les dificultats per definir el consum de risc i perjudicial per falta d'eines de freqüència i quantitat

Objective Conduct a systematic review to: 1) Identify and analyze current definitions and criteria used in scientific literature and by official organizations or institutions 2) To identify if there exists a consensus 3) Give recommendations for further studies

Methodology 1582 unique entries by title/abstract 73 fulfilling inclusion criteria 43 not fulfilling exclusion criteria + 3 references 46 articles finally included 25 definitions using screening tools 17 definitions for problematic cannabis use 8 definitions for risky cannabis use 21 definitions using frequency of cannabis use 7 definitions for problematic cannabis use 14 definitions for risky cannabis use 19 fulfilling exclusion criteria: -Imprecise definition (N=12) -Personal characteristics (N=7) 1508 not fulfilling inclusion criteria Flowchart resulting from the systematic literature review following PRISMA guidelines

Results Identified criteria used to define risky and problematic cannabis use: a) Screening tools (N=25) Specific for cannabis Cannabis Abuse Screening Test (CAST) Cannabis Use Disorder Identification Test (CUDIT) Cannabis Use Problems Identification Test (CUPIT) Not specific for cannabis Alcohol, Smoking and Substance Involvement Screening Test (ASSIST) CRAFFT Test b) Frequency of consumption (N=21)

Specific screening tools   Term used Author Proposed cut- off score Screened population CAST Screens for cannabis abuse 6 items Lifetime use Risky cannabis use Guitart (2012) Score ≥ 4 Adolescents Problematic cannabis use Gálera (2013) Score ≥ 2 Gheorghiev (2009) Score ≥ 3 Military sample Redonnet (2012) Young adults CUDIT Screens for cannabis abuse and dependence 10 items Past 6 months Lyvers (2013) Score≥ 8 Young adult users Adamson (2010) Score ≥ 13 Mental health patients Adamson (2003) Scores ≥ 8 Alcohol-dependent out-patients Annaheim (2008) Score 6-8 Adolescents and young adults Thake (2011) Scores ≥ 6 Scores≥ 8 General population Health care settings Annaheim (2007) General population  CUPIT Screens problematic cannabis use and risk of developing CUD after 12 months. 13 items Considers frequency & times cannabis is used in a typical occasion Past 3 and 12 months Bashford (2010) Score ≥ 12 Cannabis users recruited from different settings , including patients and general population) Tools used to identify both risky and problematic, but more often problematic use Variabilty in scores: + confusion as scores overlap are higher than for problematic use Depend on diferent populations, versions of the screening tools Screening tools consider a timeframe, but just one screening tool includes information on quantity to define risky use, although using as a proxy the hours stoned after consumig

Proposed frequency pattern Author (year)  Proposed frequency pattern Justification Risky cannabis use Caldeira (2008) 5 or more times in the past year Empirically decided Coffey (2003) Weekly cannabis use Cohort study Degenhardt (2008) At least weekly Díaz (2011) Almost weekly Fischer (2012) Gmel et al (2010) At least twice a week during the past 6 months, or more than once per week during the past month Ogborne (2000) At least weekly during the year of the survey Survey result Patton (2003, 2007) Weekly (moderate risk) or daily (high risk) Van Ours (2013) Several consumptions per week Problematic cannabis use Kay- Lambkin (2009 y 2011) At least weekly use Kelly (2014) More than 2 days of marijuana use in the past 12 months Survey result (children) Steinhausen (2007) More than 3 times in the past month More definitions for risky use Problematic cannabis use less frequent than risky use We observe more heterogenity in definitions Can be explained as more than 50% frequencies proposed are not evidence-based Incomplete definitions: No time-frames included No quantites included Shouldn’t there be specific considerations for high risk groups?

Institutional web-pages Only three included a definition related to risky or problematic cannabis use EMCDDA High risk users are frequent cannabis users, defined as consuming 20 days or more a month. Canadian Centre on Substance Abuse “At risk” cannabis users are individuals consuming less than 1 gram, a few times a week, at night and especially at weekends during several years with periods of high intensity usage PNSD Binary CAST scores of 2-3 are indicative of a low risk and scores above 4 suggest a high risk to develop problems related to cannabis use. Variability within institutional definitions One definition uses quantity but is actual based on medical marihuana use

Limitations of current criteria No consensus = high variability Incomplete criteria Mostly not evidence based Quantities not considered No timeframes Specific at risk groups are not reflected

Recommendation Clearly differentiate both concepts Work for evidence based and complete definitions Quantity & frequency Timeframes Specific considerations for high-risk groups Risky use  Quantity and frequency Problematic use  Screening tool

Conclusions To promote early interventions we need to be able to identify at risk and problematic cannabis users Consensus on definitions is decisive Need to homogenize and complete definitions Recommendations to the public

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