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Cited by 914Cannabis and Cannabinoid ResearchSubstance Abuse Treatment and OutcomesMental Health Treatment and Access

Association of Cannabis Use in Adolescence and Risk of Depression, Anxiety, and Suicidality in Young Adulthood

Open access
Gobbi, Gabriella, Atkin, Tobias, Zytynski, Tomasz, Wang, Shouao, Askari, Sorayya, Boruff, Jill, Ware, Mark, Marmorstein, Naomi +3 more·2019·JAMA Psychiatry
DOI 10.1001/jamapsychiatry.2018.4500PMC PMC6450286
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Abstract

Importance: Cannabis is the most commonly used drug of abuse by adolescents in the world. While the impact of adolescent cannabis use on the development of psychosis has been investigated in depth, little is known about the impact of cannabis use on mood and suicidality in young adulthood. Objective: To provide a summary estimate of the extent to which cannabis use during adolescence is associated with the risk of developing subsequent major depression, anxiety, and suicidal behavior. Data Sources: Medline, Embase, CINAHL, PsycInfo, and Proquest Dissertations and Theses were searched from inception to January 2017. Study Selection: Longitudinal and prospective studies, assessing cannabis use in adolescents younger than 18 years (at least 1 assessment point) and then ascertaining development of depression in young adulthood (age 18 to 32 years) were selected, and odds ratios (OR) adjusted for the presence of baseline depression and/or anxiety and/or suicidality were extracted. Data Extraction and Synthesis: Study quality was assessed using the Research Triangle Institute item bank on risk of bias and precision of observational studies. Two reviewers conducted all review stages independently. Selected data were pooled using random-effects meta-analysis. Main Outcomes and Measures: The studies assessing cannabis use and depression at different points from adolescence to young adulthood and reporting the corresponding OR were included. In the studies selected, depression was diagnosed according to the third or fourth editions of Diagnostic and Statistical Manual of Mental Disorders or by using scales with predetermined cutoff points. Results: After screening 3142 articles, 269 articles were selected for full-text review, 35 were selected for further review, and 11 studies comprising 23 317 individuals were included in the quantitative analysis. The OR of developing depression for cannabis users in young adulthood compared with nonusers was 1.37 (95% CI, 1.16-1.62; I2 = 0%). The pooled OR for anxiety was not statistically significant: 1.18 (95% CI, 0.84-1.67; I2 = 42%). The pooled OR for suicidal ideation was 1.50 (95% CI, 1.11-2.03; I2 = 0%), and for suicidal attempt was 3.46 (95% CI, 1.53-7.84, I2 = 61.3%). Conclusions and Relevance: Although individual-level risk remains moderate to low and results from this study should be confirmed in future adequately powered prospective studies, the high prevalence of adolescents consuming cannabis generates a large number of young people who could develop depression and suicidality attributable to cannabis. This is an important public health problem and concern, which should be properly addressed by health care policy.

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Crossref · 10.1001/jamapsychiatry.2018.4500

Cites

83 of 87 references verified0 citation errors · 1 not checkable

Statistics

Nothing to recompute.

Claims the paper makes

19 of 43 cited sources checked · 6 supported · 0 flagged · accuracy not yet measured

  • Findingcitation

    One study of 1232 first-year college students established 6 cannabis use trajectories varying from nonuse, to late-increase use, to college-peak use, to chronic use.

    “For example, 1 study of 1232 first-year college students established 6 cannabis use trajectories varying from nonuse, to late-increase use, to collegepeak use, to chronic use.35”
    Quote in the paperNot a substantial claim1 of 1 sources checked
    • cites [35] 35. Caldeira KM, O'Grady KE, Vincent KB, Arria AM. Marijuana use trajectories during the post-college transition: health outcomes in young adulthood. Drug Alcohol Depend. 2012;125(3):267-275. doi:10. 1016/j.drugalcdep.2012.02.022 source

      Results §3.1 identifies six marijuana-use trajectories, including Non-Use, Late-Increase, College-Peak, and Chronic. Methods §2.2 reports 1,253 first-year college students, not 1,232; the trajectory-group counts in Results §3.1 also sum to 1,253. (LLM, conf=0.91)

      Experimental — accuracy not yet measured
  • Findingcitation

    A few studies failed to find a statistical correlation between cannabis and depressive symptoms.

    “In contrast, a few studies failed to find a statistical correlation between cannabis and depressive symptoms.39,48,55,56,59,60”
    Quote in the paperNot a substantial claim2 of 3 sources checked
    • cites [39] 39. Epstein M, Hill KG, Nevell AM, et al. Trajectories of marijuana use from adolescence into adulthood: environmental and individual correlates. Dev Psychol. 2015;51(11):1650-1663. doi:10.1037/dev0000054 source
    • cites [48] 48. Meier MH, Hill ML, Small PJ, Luthar SS. Associations of adolescent cannabis use with academic performance and mental health: a longitudinal study of upper middle class youth. Drug Alcohol Depend. 2015;156:207-212. doi:10. 1016/j.drugalcdep.2015.09.010 source

      The Discussion reports no statistically significant association between cannabis use and internalizing symptoms in this sample. It also states that the measure combined depression and anxiety symptoms, so the paper does not establish a null association for depressive symptoms specifically. (LLM, conf=0.86)

      Experimental — accuracy not yet measured
    • cites [55] 55. Scholes-Balog KE, Hemphill SA, Evans-Whipp TJ, Toumbourou JW, Patton GC. Developmental trajectories of adolescent cannabis use and their relationship to young adult social and behavioural adjustment: a longitudinal study of Australian youth. Addict Behav. 2016;53:11-18. doi:10.1016/j. addbeh.2015.09.008 source
  • Premisecitation

    The brain remains in a state of active, experience-guided development from the prenatal period through childhood and adolescence until the age of approximately 21 years.

    “The brain indeed remains in a state of active, experienceguided development from the prenatal period through childhood and adolescence until the age of approximately 21 years.20,21”
    Quote in the paperSubstantial claim1 of 2 sources checked
    • cites [20] 20. Giedd JN, Blumenthal J, Jeffries NO, et al. Brain development during childhood and adolescence: a longitudinal MRI study. Nat Neurosci. 1999;2(10): 861-863. doi:10.1038/13158 source
    • cites [21] 21. Fuhrmann D, Knoll LJ, Blakemore SJ. Adolescence as a sensitive period of brain development. Trends Cogn Sci. 2015;19(10):558-566. doi:10.1016/j.tics.2015.07.008 source

      The ‘Brain development in adolescence’ section describes protracted brain development, and the Conclusion says some adolescent development may be susceptible to environmental influences. The figure text describes changes from infancy through adolescence and into the twenties, but the paper does not establish continuous experience-guided development from the prenatal period or an endpoint at approximately age 21. Page numbers are unavailable in our copy. (LLM, conf=0.87)

      Experimental — accuracy not yet measured
  • Findingcitation

    Two trajectory studies demonstrated that quitting cannabis by the end of adolescence did not protect people from some of the serious effects of the drug.

    “Two trajectory studies demonstrated that quitting cannabis by the end of adolescence did not protect people from some of the serious effects of the drug.16,39”
    Quote in the paperSubstantial claim2 of 2 sources checked
    • cites [16] 16. Brook JS, Lee JY, Brown EN, Finch SJ, Brook DW. Developmental trajectories of marijuana use from adolescence to adulthood: personality and social role outcomes. Psychol Rep. 2011;108(2):339- 357. doi:10.2466/10.18.PR0.108.2.339-357 source

      The Discussion (Limitations; page unavailable) says the maturing-out group was not exempt from adverse adult outcomes despite decreased marijuana use. It does not establish that participants quit by the end of adolescence, and the paper reports associations with outcomes rather than demonstrating that cannabis caused them. (LLM, conf=0.88)

      Experimental — accuracy not yet measured
    • cites [39] 39. Epstein M, Hill KG, Nevell AM, et al. Trajectories of marijuana use from adolescence into adulthood: environmental and individual correlates. Dev Psychol. 2015;51(11):1650-1663. doi:10.1037/dev0000054 source

      The Results (Adult Functioning Factors at Age 33; page not supplied) report poorer educational and economic outcomes for the adolescent-limited group despite little to no marijuana use by their early 30s. But the Results (Key Developmental Points; page not supplied) place peak use at age 18 and desistance around ages 21–24, not quitting by the end of adolescence. The Discussion also says the study cannot determine whether marijuana use caused the disparities. (LLM, conf=0.90)

      Experimental — accuracy not yet measured
  • Findingcitation

    Girls seem more susceptible than boys to develop adult depression if they smoke cannabis in adolescence.

    “moreover, girls seem more susceptible than boys to develop adult depression if they smoke cannabis in adolescence.15”
    Quote in the paperNot a substantial claim1 of 1 sources checked
    • cites [15] 15. Patton GC, Coffey C, Carlin JB, Degenhardt L, Lynskey M, Hall W. Cannabis use and mental health in young people: cohort study. BMJ. 2002;325 (7374):1195-1198. doi:10.1136/bmj.325.7374.1195 source

      The “Cannabis in adolescence and depression in young adults” section reports a significant interaction between sex and weekly-or-more-frequent teenage cannabis use, with higher later risk in girls. The claim omits two limits: the finding concerns frequent use, not any cannabis use, and the measured outcome is depression and anxiety together, not depression alone. Page numbers were not available in our copy. (LLM, conf=0.86)

      Experimental — accuracy not yet measured
  • May combine two claims. 23
  • Classified as probably not a substantial claim. 25

  • May combine two claims.

    Premisecitation

    Two other systematic reviews and meta-analyses analyzed the association between cannabis and depression but focused on use in the general population (adolescents and adults) and thus could not study the window of risk in adolescence.

    “Two other systematic reviews and meta-analyses 23,24 analyzed the association between cannabis and depression, but those studies likewise focused on use in the general population (adolescents and adults) and thus could not study the window of risk in adolescence.”
    Quote in the paperSubstantial claim1 of 2 sources checked
    • cites [23] 23. Moore TH, Zammit S, Lingford-Hughes A, et al. Cannabis use and risk of psychotic or affective mental health outcomes: a systematic review. Lancet. 2007;370(9584):319-328. doi:10.1016/S0140-6736 (07)61162-3 source

      The indexed copy’s Search Strategy and Selection Criteria section concerns breast and cervical cancer, not cannabis or depression. Searches for cannabis, depression, and an adolescent window of risk returned no relevant passage. The supplied source title also does not match the text held in the indexed copy, so this copy cannot verify the attribution. (LLM, conf=0.75)

      Experimental — accuracy not yet measured
    • cites [24] 24. Degenhardt L, Hall W, Lynskey M. Exploring the association between cannabis use and depression. Addiction. 2003;98(11):1493-1504. doi:10.1046/j. 1360-0443.2003.00437.x source

  • Probably not a substantial claim: may not pass S3 (load-bearing). May combine two claims.

    Study design and conductcitation

    The Medline strategy was developed with input from the research team and then peer reviewed by a second librarian using the PRESS standard.

    “The Medline strategy was developed with input from the research team and then peer reviewed by a second librarian using the PRESS standard.27”
    Quote in the paperNot a substantial claim1 of 1 sources checked
    • cites [27] 27. McGowan J, Sampson M, Lefebvre C. An evidence based checklist for the peer review of electronic search strategies (PRESS EBC). Evid Based Libr Inf Pract. 2010;5(1):149-154. doi:10. 18438/B8SG8R source

  • Probably not a substantial claim: may not pass S3 (load-bearing). May combine two claims.

    Findingcitation

    Another study found an increased risk of depression among adolescents who possessed the short allele of the serotonin transporter gene (5-HTTLPR genotype) (S/S), evincing an interaction between genetics and an environmental exposure (cannabis).

    “Another study 69 found an increased risk of depression among adolescents who possessed the short allele of the serotonin transporter gene (5-HTTLPR genotype) (S/S), evincing an interaction between genetics and an environmental exposure (cannabis).”
    Quote in the paperNot a substantial claim1 of 1 sources checked
    • cites [69] 69. Otten R, Engels RC. Testing bidirectional effects between cannabis use and depressive symptoms: moderation by the serotonin transporter gene. Addict Biol. 2013;18(5):826-835. doi:10.1111/j.1369-1600.2011.00380.x source

      Split into 2 atoms — 0 confirmed, 2 partially supported, 0 disputed, 0 misattributed, 0 unverifiable. Expand the claim to see per-atom verdicts.

      Experimental — accuracy not yet measured

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Study design and conductown data

    The cohort with the highest OR for depression was entirely reanalyzed using both classical multivariable regression and propensity score adjusted regression methods.

    “The cohort with the highest OR for depression 46 was entirely reanalyzed using both the classical methods for factors adjustment (multivariate regression analysis) and using the propensity score adjusted regression meth-ods to better estimate the differences in the distribution of the confounding variables 67 using SAS, version 9.4 (SAS Institute Inc).”
    Quote in the paperNot a substantial claim1 of 2 sources checked
    • cites [46] 46. Marmorstein NR, Iacono WG. Explaining associations between cannabis use disorders in adolescence and later major depression: a test of the psychosocial failure model. Addict Behav. 2011; 36(7):773-776. doi:10.1016/j.addbeh.2011.02.006 source

      The Results report an odds ratio of 2.95 for later major depression in the Minnesota twin cohort, supporting its identification as a cohort with a depression OR. Our copy does not establish that this was the highest OR among cohorts. The reanalysis using multivariable and propensity-score-adjusted regression is described in the citing sentence as the citing authors’ own work, not as a method used by this source. (LLM, conf=0.77)

      Experimental — accuracy not yet measured
    • cites [67] 67. Schneeweiss S, Rassen JA, Glynn RJ, Avorn J, Mogun H, Brookhart MA. High-dimensional propensity score adjustment in studies of treatment effects using health care claims data. Epidemiology. 2009;20(4):512-522. doi:10.1097/EDE. 0b013e3181a663cc

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Interpretationcitation

    These differences may constitute the neurobiological underpinning of the cognitive and behavioral deficits that are observed in humans.

    “these differences may constitute the neurobiological underpinning of the cognitive and behavioral deficits that are observed in humans.9”
    Quote in the paperNot a substantial claim1 of 1 sources checked
    • cites [9] 9. Volkow ND, Baler RD, Compton WM, Weiss SR. Adverse health effects of marijuana use. N Engl J Med. 2014;370(23):2219-2227. doi:10.1056/ NEJMra1402309 source

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Findingcitation

    Another study supported a self-medication hypothesis in male individuals, in which adolescents with higher depressive symptoms at baseline used more cannabis.

    “Another study supported a self-medication hypothesis in male individuals, in which adolescents with higher depressive symptoms at baseline used more cannabis.59”
    Quote in the paperNot a substantial claim1 of 1 sources checked
    • cites [59] 59. Wilkinson AL, Halpern CT, Herring AH. Directions of the relationship between substance use and depressive symptoms from adolescence to young adulthood. Addict Behav. 2016;60:64-70. doi:10.1016/j.addbeh.2016.03.036 source

  • May combine two claims.

    Premisecitation

    Adolescent rats treated with THC have fewer synaptic contacts during adulthood and reduced efficiency of hippocampal networks.

    “Adolescent rats treated with THC also have fewer synaptic contacts during adulthood and reduced efficiency of hippocampal networks 75”
    Quote in the paperNot a substantial claim1 of 1 sources checked
    • cites [75] 75. Gilman JM, Kuster JK, Lee S, et al. Cannabis use is quantitatively associated with nucleus accumbens and amygdala abnormalities in young adult recreational users. J Neurosci. 2014;34(16): 5529-5538. doi:10.1523/JNEUROSCI.4745-13.2014 source

      The Introduction and Discussion describe THC-related structural changes in rats’ nucleus accumbens, but do not report fewer synaptic contacts in adulthood or reduced hippocampal-network efficiency. Searches for adolescent THC exposure, synaptic contacts, and hippocampal-network efficiency found no passage addressing those outcomes. The Discussion’s report of no hippocampal effects in one rat study does not establish a contradiction for the adolescent-treatment claim. (LLM, conf=0.76)

      Experimental — accuracy not yet measured

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Study design and conductcitation

    PRISMA reporting guideline for reporting of systematic reviews was followed and fulfilled.

    “Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) reporting guideline for reporting of systematic reviews were followed and fulfilled.29”
    Quote in the paperNot a substantial claim1 of 1 sources checked
    • cites [29] 29. Moher D, Liberati A, Tetzlaff J, Altman DG, PRISMA Group. Preferred reporting items for systematic reviews and meta-analyses: the PRISMA statement. PLoS Med. 2009;6(7):e1000097. doi:10.1371/journal.pmed.1000097 source

  • May combine two claims.

    Findingcitation

    Other studies found significant positive associations between cannabis use during adolescence and later anxiety and depression paralleled by academic unpreparedness, delinquency, and poorer academic performance.

    “Other studies likewise found significant positive associations between cannabis use during adolescence and later anxiety and depression paralleled by academic unpreparedness, delinquency, and poorer academic performance.36”
    Quote in the paperNot a substantial claim1 of 1 sources checked
    • cites [36] 36. D'Amico EJ, Tucker JS, Miles JN, Ewing BA, Shih RA, Pedersen ER. Alcohol and marijuana use trajectories in a diverse longitudinal sample of adolescents: examining use patterns from age 11 to 17 years. Addiction. 2016;111(10):1825-1835. doi:10. 1111/add.13442 source

      The Abstract Findings and Results (Effects of use on wave 7 outcomes; page not provided) report significant associations between greater adolescent marijuana use and academic unpreparedness, delinquency, poorer academic performance, and poorer mental health in high school. The Methods (Measures; page not provided) say the mental-health scale primarily reflects anxiety and depression, but the paper does not report separate significant associations for anxiety and depression. (LLM, conf=0.86)

      Experimental — accuracy not yet measured

  • Probably not a substantial claim: may not pass S3 (load-bearing). May combine two claims.

    Premisecitation

    Some of the detrimental effects of cannabis on behavior seem more pronounced in females in both animals and humans, although this finding remains controversial.

    “Some of the detrimental effects of cannabis on behavior seem more pronounced in females in both animals 19 and humans, 15 although this finding remains controversial.”
    Quote in the paperNot a substantial claim1 of 2 sources checked
    • cites [19] 19. Rubino T, Parolaro D. The impact of exposure to cannabinoids in adolescence: insights from animal models. Biol Psychiatry. 2016;79(7):578-585. doi:10.1016/j.biopsych.2015.07.024 source
    • cites [15] 15. Patton GC, Coffey C, Carlin JB, Degenhardt L, Lynskey M, Hall W. Cannabis use and mental health in young people: cohort study. BMJ. 2002;325 (7374):1195-1198. doi:10.1136/bmj.325.7374.1195 source

  • May combine two claims.

    Findingcitation

    The 6 cannabis trajectory groups were not significantly different on year-1 health-related variables but differed on all 10-year mental health outcomes tested, including depression and anxiety.

    “The 6 cannabis trajectory groups were not significantly different on year-1 health-related variables but differed on all 10-year mental health outcomes tested, including depression and anxiety.”
    Quote in the paperNot a substantial claim

  • May combine two claims.

    Findingcitation

    There is evidence that younger users of cannabis (aged 14 to 15 years) were at significantly higher risk of suicidal behaviors, although overall the association between cannabis use and depression did not vary with age.

    “There is evidence that younger users of cannabis (aged 14 to 15 years) were at significantly higher risk of suicidal behaviors, although, overall, the association between cannabis use and depression did not vary with age 42”
    Quote in the paperSubstantial claim0 of 1 sources checked
    • cites [42] 42. Fergusson DM, Horwood LJ, Swain-Campbell N. Cannabis use and psychosocial adjustment in adolescence and young adulthood. Addiction. 2002;97(9):1123-1135. doi:10.1046/j.1360-0443. 2002.00103.x source

  • Probably not a substantial claim: may not pass S3 (load-bearing). May combine two claims.

    Findingcitation

    This study failed to support a link between using cannabis as an adolescent and later depression in male or female individuals but found instead a positive association between tobacco and depression.

    “This study failed to support a link between using cannabis as an adolescent and later depression in male or female individuals but found instead a positive association between tobacco and depression.”
    Quote in the paperNot a substantial claim

  • May combine two claims.

    Findingown data

    Twenty-four longitudinal studies did not report OR poolable data or reported the same cohorts and were thus not included in the meta-analysis.

    “Twenty-four longitudinal studies did not report OR poolable data or reported the same cohorts and were thus not included in the meta-analysis”
    Quote in the paperNot a substantial claim

  • May combine two claims.

    Findingown data

    A total of 11 articles met the inclusion criteria for the meta-analysis: 7 for depression, 3 for anxiety, 3 for suicidal ideation, and 3 for suicide attempts.

    “A total of 11 articles met the inclusion criteria for the metaanalysis (Figure 1): 7 for depression 10,16,34,38,[44][45][46] ; 3 for anxiety, 16,38,44 3 for suicidal ideation, 41,47,57 and 3 for suicide attempts.10,54,57”
    Quote in the paperSubstantial claim

  • May combine two claims.

    Findingown data

    The pooled OR among studies from the United States was 1.54 (95% CI, 1.20-1.98); the pooled OR among studies from other countries was 1.24 (95% CI, 0.99-1.56; P = .21).

    “The pooled OR among studies from the United States was 1.54 (95% CI, 1.20-1.98);the pooled OR among studies from other countries was 1.24 (95% CI, 0.99-1.56;P = .21).”
    Quote in the paperNot a substantial claim

  • May combine two claims.

    Findingown data

    After removing the study by Degenhardt et al when assessing the association of cannabis with depression, the new OR was 1.40 (95% CI, 1.17-1.67) and remained significant.

    “The new OR was 1.40 (95% CI, 1.17-1.67)and remained significant.”
    Quote in the paperNot a substantial claim

  • May combine two claims.

    Premisecitation

    A meta-analysis published in 2014 examined the association of cannabis use and depression, but included youth and adults and therefore did not estimate the specific risk of use during adolescence.

    “A meta-analysis published in 2014 examined the association of cannabis use and depression, 22 but this study included youth and adults and therefore did not estimate the specific risk of use during adolescence.”
    Quote in the paperSubstantial claim0 of 1 sources checked
    • cites [22] 22. Lev-Ran S, Roerecke M, Le Foll B, George TP, McKenzie K, Rehm J. The association between cannabis use and depression: a systematic review and meta-analysis of longitudinal studies. Psychol Med. 2014;44(4):797-810. doi:10.1017/ S0033291713001438 source

  • May combine two claims.

    Premisecitation

    The 2014 meta-analysis did not consider the risk of suicidal behavior and the comorbid anxiety often associated with depression.

    “The study also did not consider the risk of suicidal behavior and the comorbid anxiety often associated with depression.”
    Quote in the paperSubstantial claim0 of 1 sources checked
    • cites [22] 22. Lev-Ran S, Roerecke M, Le Foll B, George TP, McKenzie K, Rehm J. The association between cannabis use and depression: a systematic review and meta-analysis of longitudinal studies. Psychol Med. 2014;44(4):797-810. doi:10.1017/ S0033291713001438 source

  • Probably not a substantial claim: may not pass S3 (load-bearing). May combine two claims.

    Study design and conductcitation

    Database search strategies complied with the Institute of Medicine standards and were not limited by language or by year of publication.

    “Database search strategies complied with the Institute of Medicine standards 25 and were not limited by language or by year of publication.”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites [25] 25. Eden J, Levit L, Berg A, Morton S. Finding What Works in Health Care: Standards for Systematic Reviews. Washington, DC: National Academies Press; 2011.

      Couldn’t be matched to a paper in Crossref, so it can’t be checked.

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Study design and conductown data

    A sensitivity analysis was done to rule out possible cohort overlap.

    “One set of sensitive analysis was done to rule out possible cohorts' overlap.”
    Quote in the paperNot a substantial claim

  • May combine two claims.

    Interpretationreasoning

    The effect size is modest, but considering that 20.9% of adolescents in the United States report monthly use of cannabis and 7% of US high school seniors are daily or near-daily users, the consequences of cannabis use during adolescence are magnified in young adulthood.

    “The effect size is modest, but considering that 20.9% of adolescents in the United States report monthly use of cannabis 3 and 7% of US high school seniors are daily or neardaily users, 4 the consequences of cannabis use during adolescence are magnified in young adulthood.”
    Quote in the paperNot a substantial claim0 of 2 sources checked
    • cites [3] 3. Choo EK, Benz M, Zaller N, Warren O, Rising KL, McConnell KJ. The impact of state medical marijuana legislation on adolescent marijuana use. J Adolesc Health. 2014;55(2):160-166. doi:10.1016/j. jadohealth.2014.02.018 source
    • cites [4] 4. Johnston LD. OMP, Bachman J, Schulenberg J. Monitoring the Future National Results on Drug Use: 2012 Overview. Ann Arbor, Michigan: Institute for Social Research, University of Michigan; 2013.

      Couldn’t be matched to a paper in Crossref, so it can’t be checked.

  • Classified as probably not a substantial claim.

    Study design and conductnone given

    When multiple studies reported on the same population cohort at different time points, only the study reporting the longest follow-up was chosen.

    “When multiple studies were found reporting on the same population cohort at different time points, only the study reporting the longest follow-up was chosen.”
    Quote in the paperSubstantial claim

  • May combine two claims.

    Interpretationown data

    This meta-analysis shows that cannabis consumption in adolescence is associated with increased risk of developing major depression in young adulthood and suicidality, especially suicidal ideation.

    “This meta-analysis shows that cannabis consumption in adolescence is associated with increased risk of developing major depression in young adulthood and suicidality, especially suicidal ideation.”
    Quote in the paperSubstantial claim

  • May combine two claims.

    Premisecitation

    These neuroanatomic alterations are mostly characterized by a decrease in volume (hippocampus, amygdala, prefrontal cortex) or greater gray matter density in cannabis users than in controls in the left nucleus accumbens extending to subcallosal cortex, hypothalamus, sublenticular extended amygdala, and left amygdala.

    “and are mostly characterized by a decrease in volume (hippocampus, amygdala, prefrontal cortex) or greater gray matter density in cannabis users than in controls in the left nucleus accumbens extending to subcallosal cortex, hypothalamus, sublenticular extended amygdala, and left amygdala.74”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites [74] 74. Lorenzetti V, Solowij N, Yücel M. The Role of cannabinoids in neuroanatomic alterations in cannabis users. Biol Psychiatry. 2016;79(7):e17-e31. doi:10.1016/j.biopsych.2015.11.013

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Study design and conductnone given

    Two reviewers independently assessed all titles and abstracts along with full texts of potentially relevant articles.

    “Two reviewers (T.A. and T.Z.) independently assessed all titles and abstracts along with full texts of potentially relevant articles.”
    Quote in the paperNot a substantial claim

  • Classified as probably not a substantial claim.

    Study design and conductnone given

    Only longitudinal prospective cohort studies reporting outcome data about cannabis use at baseline and depression at follow-up and adjusting for depression and/or anxiety and/or suicidality at baseline were included in the meta-analysis.

    “Only longitudinal prospective cohort studies reporting outcome data about cannabis use (baseline) and depression (follow-up) and adjusting for depression and/or anxiety and/or suicidality at baseline were included in the metaanalysis (eTable 1 in the Supplement).”
    Quote in the paperSubstantial claim

  • Classified as probably not a substantial claim.

    Study design and conductnone given

    Only studies reporting adjusted OR for basal depression or anxiety or suicidality were included in the meta-analysis.

    “Only studies reporting adjusted OR for basal depression or anxiety or suicidality were included in the metaanalysis.”
    Quote in the paperSubstantial claim

  • Classified as probably not a substantial claim.

    Study design and conductreasoning

    Included studies were controlled and adjusted for age, sex, and depression and/or anxiety at baseline.

    “controlled and adjusted for the following confounding factors: age, sex, and depres-sion and/or anxiety at baseline.”
    Quote in the paperSubstantial claim

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Premisecitation

    Additional studies demonstrate the neurobiological and pathophysiological depression-like behavior of adolescent rats when exposed to cannabinoids.

    “Additional studies further demonstrate the neurobiological and the pathophysiological depressionlike behavior of adolescent rats when exposed to cannabinoids.19”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites [19] 19. Rubino T, Parolaro D. The impact of exposure to cannabinoids in adolescence: insights from animal models. Biol Psychiatry. 2016;79(7):578-585. doi:10.1016/j.biopsych.2015.07.024 source

  • May combine two claims.

    Premisecitation

    Animal studies have demonstrated that cannabis consumption during adolescence produces an increase in anhedonia and anxiety in adulthood, paralleled by a decrease in serotonin and an increase in norepinephrine.

    “Animal studies have demonstrated that cannabis consumption during adolescence produces an increase in anhedonia and anxiety in adulthood, paralleled by a decrease in serotonin (a neurotransmitter linked to depression) and an increase in norepinephrine (a neurotransmitter linked to anxiety).17”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites [17] 17. Bambico FR, Nguyen N-T, Katz N, Gobbi G. Chronic exposure to cannabinoids during adolescence but not during adulthood impairs emotional behaviour and monoaminergic neurotransmission. Neurobiol Dis. 2010;37(3):641- 655. doi:10.1016/j.nbd.2009.11.020 source

  • Probably not a substantial claim: may not pass S3 (load-bearing). May combine two claims.

    Premisecitation

    Following long-term adolescent cannabinoid exposure, dopamine neurons become less responsive to the stimulating action of cannabinoids and a long-lasting cross-tolerance for morphine, cocaine, and amphetamine occurs.

    “Studies have also demonstrated that, following long-term adolescent cannabinoid exposure, dopamine neurons become less responsive to the stimulating action of cannabinoids and a long-lasting cross-tolerance for morphine, cocaine, and amphetamine occur.18”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites [18] 18. Pistis M, Perra S, Pillolla G, Melis M, Muntoni AL, Gessa GL. Adolescent exposure to cannabinoids induces long-lasting changes in the response to drugs of abuse of rat midbrain dopamine neurons. Biol Psychiatry. 2004;56(2):86-94. doi:10.1016/j. biopsych.2004.05.006 source

  • Probably not a substantial claim: may not pass S3 (load-bearing), S4 (based).

    Interpretationnone given

    This study is consistent with the greater part of research on brain imaging literature demonstrating the negative influence of cannabis in brain plasticity during development.

    “This study also is consistent with the greater part of research on brain imaging literature demonstrating the negative influence of cannabis in brain plasticity during the development.”
    Quote in the paperNot a substantial claim

  • May combine two claims.

    Interpretationcitation

    Most of the 24 nonpoolable longitudinal studies reported a positive correlation between adolescent cannabis use and later depression, reinforcing the results of the meta-analysis.

    “Interestingly, most of these studies reported a positive correlation between adolescent cannabis use and later depression, 15,[30][31][32][33][34][35][36][37]40,42,43,[49][50][51][52][53]61 reinforcing the results of the meta-analysis.”
    Quote in the paperNot a substantial claim
    • Rests on an assumption: The 24 nonpoolable longitudinal studies' positive correlations are comparable enough to the pooled results to reinforce them.

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Study design and conductcitation

    The risk of bias of the included articles was assessed using the Research Triangle Institute item bank on risk of bias and precision of observational studies.

    “The risk of bias of the included articles was assessed using the Research Triangle Institute item bank on risk of bias and precision of observational studies.63”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites [63] 63. Viswanathan M, Berkman ND. Development of the RTI item bank on risk of bias and precision of observational studies. J Clin Epidemiol. 2012;65(2): 163-178. doi:10.1016/j.jclinepi.2011.05.008 source

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Premisecitation

    The association between cannabis and suicidal behavior was previously reported by Borges et al.

    “The association between cannabis and suicidal behavior was previously reported by Borges et al. 70”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites [70] 70. Borges G, Bagge CL, Orozco R. A literature review and meta-analyses of cannabis use and suicidality. J Affect Disord. 2016;195:63-74. doi:10. 1016/j.jad.2016.02.007 source

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Study design and conductnone given

    Parental level of education, socioeconomic status, alcohol consumption, and cigarette smoking were also controlled for in almost all included studies.

    “Parental level of education, socioeconomic status, alcohol consumption, and cigarette smoking were also controlled for in almost all included studies.”
    Quote in the paperNot a substantial claim

  • Classified as probably not a substantial claim.

    Interpretationreasoning

    The findings in this meta-analysis suggest that cannabis is a serious public health concern.

    “the findings in this meta-analysis suggest that cannabis is a serious public health concern”
    Quote in the paperSubstantial claim

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Interpretationreasoning

    The content of THC in a 'one-weekly joint' likely shifted from 1980 to the present day and across locales.

    “Thus, the content of THC in”
    Quote in the paperNot a substantial claim

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Study design and conductreasoning

    It was not possible to evaluate the exact quantity of cannabis consumed among adolescents in individual studies because they used measures of frequency of use rather than the precise quantity.

    “It was also not possible to evaluate the exact quantity of cannabis consumed among adolescents in individual studies since they used measures of frequency of use and rather than the precise quantity.”
    Quote in the paperNot a substantial claim

  • Probably not a substantial claim: may not pass S3 (load-bearing). May combine two claims.

    Premisecitation

    The potency of cannabis has generally increased since 1980 and varies across geographic location.

    “Furthermore, the potency of cannabis has generally increased since 1980, 76 and potency varies across geographic location.8”
    Quote in the paperNot a substantial claim0 of 2 sources checked
    • cites [76] 76. Rubino T, Realini N, Braida D, et al. Changes in hippocampal morphology and neuroplasticity induced by adolescent THC treatment are associated with cognitive impairment in adulthood. Hippocampus. 2009;19(8):763-772. doi:10.1002/ hipo.20554 source
    • cites [8] 8. European Drug Report 2018: Trends and Developments. Luxembourg: European Monitoring Centre for Drugs and Drug Addiction; 2018.

      Couldn’t be matched to a paper in Crossref, so it can’t be checked.

41 of 41

  • The paper relies on this without support.

    The association between adolescent cannabis use and young adult depression is causal, for the purpose of estimating population attributable risk.

    “In this study, the estimated population attributable risk is 7.2%.”
    “This translates to some 413 326 young adult cases of depression potentially attributable to cannabis exposure”

  • The paper relies on this without support.

    The 24 nonpoolable longitudinal studies' positive correlations are comparable enough to the pooled results to reinforce them.

    “Interestingly, most of these studies reported a positive correlation between adolescent cannabis use and later depression, 15,[30][31][32][33][34][35][36][37]40,42,43,[49][50][51][52][53]61 reinforcing the results of the meta-analysis.”

  • The paper relies on this without support.

    Self-reported questionnaires accurately classify adolescent cannabis use in the included studies.

    “Cannabis use in most studies was measured with a selfreported questionnaire.”

  • The paper relies on this without support.

    The diagnostic tools and scales used in included studies validly identify depression, anxiety, and suicidality.

    “Depression or anxiety was considered in a dichotomous manner according to the third and fourth editions of the Diagnostic and Statistical Manual of Mental Disorders 62 criteria or with scales (eg, Symptom Checklist-90, Composite International Diagnostic Interview, General Health Questionnaire-12, Clinical Interview Schedule-Revised) with a determined cutoff points (eTable 1 in the Supplement).”
4 of 4

Claims other papers make about this one

Each is checked against this paper’s own text: does it say what the citing paper says it does?

  • There is an association between youth cannabis use and suicide attempts (OR 3.46).

    “In one review of three studies, including 13,687 participants, Gobbi et al. (2019) found an association between youth cannabis use and suicide attempts (OR: 3.46).”

    From Risk and Protective Factors of Self-harm and Suicidality in Adolescents: An Umbrella Review with Meta-Analysis (2024) · cites this paper as Gobbi et al. (2019)

    The Results of the Meta-analyses report three studies of suicide attempts and a pooled OR of 3.46 for adolescent cannabis use. The passages in our copy do not substantiate the citing sentence’s figure of 13,687 participants. (LLM, conf=0.85)

    Experimental — accuracy not yet measured

  • Heavier and more frequent cannabis use was associated with suicidal ideation and suicide attempts in adolescents and young adults.

    “Heavier and more frequent cannabis use was associated with suicidal ideation and suicide attempts in adolescents and young adults [48, 49].”

    From Cannabis, cannabinoids and health: a review of evidence on risks and medical benefits (2025) · cites this paper as [48]

    The Results of the Meta-analyses report associations between adolescent cannabis use and subsequent suicidal ideation and suicide attempts in adolescence or young adulthood. Parameters Definitions says the pooled analysis used the highest-frequency category when studies reported multiple use frequencies, but it does not establish that risk rose with frequency. The Limitations say studies measured frequency rather than precise quantity, so the claim about heavier use is not supported. (LLM, conf=0.85)

    Experimental — accuracy not yet measured

  • There is an association between youth cannabis use and suicidal ideation (OR 1.50).

    “In reviews of behavior issues and suicide ideation, Gobbi et al. (2019) found an association between youth cannabis use and suicidal ideation (OR:1.50).”

    From Risk and Protective Factors of Self-harm and Suicidality in Adolescents: An Umbrella Review with Meta-Analysis (2024) · cites this paper as Gobbi et al. (2019)

  • Cannabis consumption is associated with a higher risk for depression and suicidality, particularly among young people.

    “Another area of concern with cannabis consumption is its as sociation with a higher risk for depression and suicidality, particu larly among young people.”

    From Substance use disorders: a comprehensive update of classification, epidemiology, neurobiology, clinical aspects, treatment and prevention (2023) · cites this paper as [131]

  • A recent meta-analysis reported an OR of 1.37 (95% CI: 1.16-1.62) for developing depression in young cannabis users compared to non-users.

    “a recent meta- analysis reported an OR of 1.37 (95% CI: 1.16- 1.62) for developing depression, and of 3.46 (95% CI: 1.53- 7.84) for suicidal attempt, in young cannabis users when compared to non- users 131 .”

    From Substance use disorders: a comprehensive update of classification, epidemiology, neurobiology, clinical aspects, treatment and prevention (2023) · cites this paper as [131]

Self-check

Percentages, sums and reported differences re-computed from the paper’s own numbers.

Each contradiction between two passages listed here was confirmed by an independent check.

  • Adolescent suicide attempts are included despite the stated adult-outcome scope

    Major

    The methods place suicide attempts in early adulthood, but the pooled analysis includes attempts measured within adolescence.

  • Thirty-five studies are called meta-analysis studies although only eleven were pooled

    Minor

    One passage says 35 studies were retained for the meta-analysis; the results say only 11 met its inclusion criteria, and another passage explicitly excludes 24 of the 35 from it.

  • Adolescent suicidal ideation is included despite the stated adult-outcome scope

    Minor

    The methods place all four measured outcomes in early adulthood, but the suicidal-ideation analysis includes outcomes measured within adolescence.

  • The cited DSM edition differs from the editions named in the methods

    Minor

    The methods specify the third and fourth DSM editions while citing reference 62, which lists the fifth edition.

4 of 4

Cites

Flagged first, then by citations

Research works printed but not linked: 6

  1. Johnston, 2013, OMP, Bachman J, Schulenberg J. Monitoring the Future National Results on Drug Use: 2012 Overview
  2. Australian Institute of Health and Welfare (AIHW), 2011, 2010 National Drug Strategy Household Survey Report
  3. 2018, European Drug Report 2018: Trends and Developments
  4. Canadian Agency for Drugs and Technologies in Health, 2013, Grey Matters: a Practical Search Tool for Evidence-Based Medicine
  5. Vespa, 2017, The Changing Economics and Demographics of Young Adulthood: 1975-2016
  6. BriereFN. Association Entre Consommation de Drogues Illicites et Symptomatologie Dépressive à l’Adolescence. Une Étude Longitudinale Auprès de Jeunes Québécois Fréquentant l’École Secondaire en Milieu Défavorisé [PhD thesis]. Montreal, Canada: Université de Montréal; 2011.

Cited by

Sorted by citations

Related

Authors
Gobbi, G., Atkin, T., Zytynski, T., Wang, S., Askari, S., Boruff, J., Ware, M., Marmorstein, N., Cipriani, A., Dendukuri, N., & Mayo, N.
Affiliations
  • McGill University Health Centre (CA)
  • McGill University (CA)
  • Rutgers, The State University of New Jersey (US)
  • National Health Service (GB)
Corresponding author
Gobbi, Gabriella
ORCID
Venue
JAMA Psychiatry
Publisher
American Medical Association (AMA)
Published
2019-04-01
Volume
76
Issue
4
Pages
426
ISSN
2168-622X (ISSN-L)
DOI
10.1001/jamapsychiatry.2018.4500
PMC
PMC6450286
OpenAlex
W2912112705
Cited by
914
References
83
Citations by year
2026: 92 · 2025: 140 · 2024: 127 · 2023: 151 · 2022: 129 · 2021: 124 · 2020: 108 · 2019: 42
FWCI
12.91
Type
journal article
Language
en
Open access
Locations
  • JAMA Psychiatry (publishedVersion)
  • Europe PMC (PubMed Central) (publishedVersion)
  • PubMed Central (publishedVersion)
  • PubMed (publishedVersion)
Funders
  • National Institute for Health and Care Research (RP-2017-08-ST2-006)
  • Canadian Institutes of Health Research
Topics
  • Health Sciences › Medicine › Pharmacology › Cannabis and Cannabinoid Research
  • Health Sciences › Medicine › Epidemiology › Substance Abuse Treatment and Outcomes
  • Social Sciences › Psychology › Social Psychology › Mental Health Treatment and Access
Keywords
adolescent cannabis use, cannabis use disorder, major depressive disorder, anxiety, suicidal ideation, suicide attempts, early adulthood, mental health outcomes, risk of bias, mood disorders, substance use and mental health, psychosis risk, longitudinal cohort, risk of bias assessment
MeSH terms
Marijuana Use, Adolescent, Adolescent Behavior, Age Factors, Anxiety, Major Depressive Disorder, Humans, Suicide, Attempted, Suicidal Ideation

About these checks

Registry, retraction, Cites and statistics results are computed, not judged, with one exception: a printed reference that no index lists is read once by a model before it counts as a citation error. Claims are extracted by a model and kept only when their quote appears verbatim in the text; each cited source is then checked, with a model’s help, for whether it says what the claim relies on. Those verdicts can be wrong — read the claim’s quote and the cited source before relying on one.

Claims read by deepseek-v4.1-flash under definition version 3 (extract-v3) on 2026-10-11.

Classified by jev-1.13-20260917 (gold-guideline-v0.2) on 2026-10-11.

Cited sources are checked by gpt-6-sol.

Statistics and arithmetic are recomputed, not judged.

Confidence bands are shown only for fields calibrated on our annotated test set. None is calibrated yet, so no band is shown.

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