Table 2. Compendium of studies in a single region on factors related to the development of CUD across different levels of cannabis permissiveness (in terms of legal status).
*At the time of the study, parentheses () indicate the year of policy change, if any. Data obtained primarily from EMCDDA reports.
**Countries with missing data on the provided variables were excluded from this table.
| Region | Cannabis Legal status* | Study | N | Age of Sample | Individual Factors | Use Variables | Micro-environment Factors |
|---|---|---|---|---|---|---|---|
| Australia |
Illegal (up until medical legalization in 2016) |
Coffey et al. (2000) | 2032 | 14–15 | -- | Peer cannabis use (OR 2.1) and nicotine use (OR 2.0) associated with cannabis use. | -- |
| Degenhardt et al. (2001) | 10641 | 18+ | Participants who were cannabis dependent had a OR 2.84 for developing psychosis. | -- | -- | ||
| Clough et al. (2004) | 336 | 13–36 | -- | Alcohol use (OR 10.4) and tobacco use (OR 19.0) associated with current cannabis use. | -- | ||
| Lynskey et al. (2004) | 156 twin pairs discordant for cannabis dependence | 24–36 | Early MDD (OR 3.40 in dizygotic pairs, n.s. in monozygotic pairs) associated with subsequent cannabis use. | -- | -- | ||
| Teesson et al. (2012) | 8841 | 16–85 | Strong association between CUD and affective disorders (OR 3.0). | Prevalence of lifetime and past 12-month CUD 6% and 1% respectively. Strong association between CUD and alcohol use disorder (OR 3.6) Cannabis use more common in males (OR 2.0) and younger users (OR 4.6). |
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| Germany |
Illegal (up until medical legalization in 2017) |
Hofler et al. (1999) | 1228 | 14–17 | Affective disorders (COR 2.9) and low self-esteem (COR 1.72) associated with cannabis use. | Baseline history of alcohol use (COR 5.2) predictive of cannabis use. | Family history of substance use disorder with a cumulative odds ratio (COR) of 1.43 predictive of cannabis use. |
| Sydow et al. (2002) | 2446 | 14–24 | Baseline use of other illicit drugs predicted cannabis dependence. | Parental death before age 15 and deprived socioeconomic status predicted cannabis dependence. Availability of drugs, peers’ drug use, and a more positive attitude of the individual towards drug use predicted cannabis use. |
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| Netherlands | Depenalized | Veen et al. (2004) | 133 | 15–54 | Cannabis users had earlier first symptomatic episodes of psychosis compared to nonusers. | -- | -- |
| New Zealand | Illegal | Poulton et al. (1997) | 641 | 15–21 | -- | Males were more likely to use and be dependent on cannabis than females. Early use substantially increased the risk for the development of cannabis dependence in young adulthood. | -- |
| Norway | Illegal | Pedersen (1990) | 1311 | 13–19 | Poor mental health (determined by number of depression and anxiety symptoms) correlated with heavy use. | -- | Parental divorce correlated with heavy cannabis use (having ever used the drug 50 times or more). |
| Norway & Israel | Illegal Legal | Sznitman and Bretteville-Jensen (2015) | 2175 648 |
18+ | -- | Past year cannabis use higher in Israel (13%) compared to Norway (5%), (p<.001). | -- |
| United Kingdom |
Illegal (up until medical legalization in 2010) |
Best et al. (2005) | 2078 | 14–16 | -- | -- | Lifetime cannabis users less likely to spend time regularly with both their mothers and fathers, but more likely to spend free time with friends who smoked, drank alcohol and used illicit drugs, and with friends involved in criminal activities. |
| USA |
Mixed Illegal/decriminalized: Majority of states Legal: Alaska, California, Colorado, District of Columbia (D.C.), Hawaii, Maine, Massachusetts, Montana, Nevada, Oregon, Vermont, Washington |
Stinson et al. (2006) | 43093 | 18+ | Greater odds of dependence for those widowed/separated/divorced. In those who were cannabis dependent, the prevalence for any mood disorder was 48.2%, any anxiety disorder was 43.5%, and any personality disorder was 76.7% |
Sample had an OR of 0.3 for past 12-month cannabis dependence. In those who were cannabis dependent, the prevalence for alcohol use disorder was 54.7% and 48.7% for nicotine dependence. | -- |
| Winters & Lee (2008) | 55230 | 18–26 | -- | Increased odds ratio of initiation of use in teenage years (12–18) compared to years 22–26; ORs 3.9–7.2. | -- | ||
| Buckner et al. (2008) | 1709 | 16.6 (Average age at Time 1- start of study) 30 (Time 4- end of study) |
14-year longitudinal study. Social anxiety disorder (SAD) at study entry was associated with 6.5 greater odds of cannabis dependence. | -- | -- | ||
| Cerda et al. (2012) | 34653 | 18+ | -- | States with medical marijuana laws (MMLs) had a higher OR (1.92) for marijuana use and marijuana abuse/dependence (OR 1.81) than states without MMLs. | -- | ||
| Hasin et al. (2015) | Time 1: 43093 Time 2: 36309 |
4.1% to 9.5% increase in use prevalence, 1.5% to 2.9% increase in DSM-IV cannabis use disorder in total sample, and 35.6% to 30.5% decrease in DSM-IV cannabis use disorder in previous users from 2001 to 2013. |
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| Reed (2016) | Not listed | 21% to 31% increase in use prevalence in 18–25 year-olds from 2006 to 2014. | Increased THC-only and THC-positive motor vehicle fatalities, and decreased perception of health risk of use in adolescents from 2006 to 2014. |
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| Borodovsky et al. (2016) | 2838 | 32.5 (Average at time of study) | Individuals in MML states had a significantly higher likelihood of ever use of vaping (OR 2.04) and edibles (OR 1.78) than those in states without MMLs. In the vaping model, MML status was a significant predictor (OR: 1.77, p < 0.001), but neither recreational legalization status nor dispensary status were significant predictors (OR: 1.17–1.71, p= .27−.02). In the edible model both MML status and dispensary status were significant predictors (OR: 1.33, p = .007; OR: 1.88, p < .001) while recreational legalization status was not (OR: 1.39, p = .18). |
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| Maier et al. (2017) | Not listed | No significant differences in property and violent crime rates from 2010 to 2014 |