RESULTS Although causality is unclear , heavy and dependent cannabis use is consistently associated with a high prevalence of comorbid psychiatric disorders and learning and memory impairments that seem to recover after a period of abstinence .
Evidence regarding other cognitive domains and neurological consequences including cerebrovascular events is limited and inconsistent .
Abstinence after treatment is only achieved in a minority of cases ; treatment targeted at reduction in use appears have some success .
Potential moderators of the impact of CUD on the brain include age of onset , heaviness of use , CUD severity , the ratio of ∆9-tetrahydrocannabinol to cannabidiol , and severity of comorbid disorders .
Current evidence of long-term effects of daily cannabis use and cannabis use disorder on brain-related outcomes is suggestive rather than conclusive but use is associated with psychiatric morbidity and with cognitive impairments that recover after a period of abstinence
AIMS To summarize and evaluate our knowledge of the relationship between heavy cannabis use , Cannabis Use Disorder ( CUD ) , and the brain .
What predicts incident use of cannabis and progression to abuse and dependence? A 4-year prospective examination of risk factors in a community sample of adolescents and young adults.
OBJECTIVES To determine risk factors of incident onset of use , abuse and dependence of cannabis in a community sample of adolescents and young adults . METHODS Risk factors were examined in a prospect i ve longitudinal design across 4 years in a representative sample ( N = 2,446 ) aged 14 - 24 at the outset of the study ( EDSP ) . Patterns of DSM-IV defined cannabis use , abuse and dependence were assessed with the Composite International Diagnostic Interview ( M-CIDI ) . Potential risk factors were assessed at baseline . Incident cannabis use , abuse and dependence at second follow-up ( on average 42 months after baseline ) were the main outcome measures in this study . Associations were analyzed with logistic and negative binomial regressions . RESULTS Using 11 of a total of 56 variables examined , the predictive value of the final multiple logistic regression for incident cannabis use was moderately good ( area under the ROC curve = 0.78 ) . Cannabis use frequency was predicted in the final model by 18 variables , cannabis abuse by two variables in the younger sub sample and nine factors in the older group , and dependence by eight variables ( dependence : ROC curve area = 0.97 ) . Incident cannabis use was predicted mainly by availability of drugs , peers ' drug use , a more ' positive ' attitude towards future drug use , and regular previous use of licit drugs , while cannabis dependence was predicted primarily by parental death before age 15 , deprived socio-economic status , and baseline use of other illicit drugs . CONCLUSION Different factors predict the onset or severity of cannabis use and the progression to abuse and dependence . In addition to well-documented risk factors such as peer group pressure , drug availability , and low self-esteem , findings suggest that family history ( e.g. parental mental disorders , early parental death ) , and prior experiences with legal drugs play a significant role in the initiation of cannabis consumption and the transition to cannabis use disorders in adolescents and young adults . Findings suggest that early intervention and prevention might be improved by better targeted treatment
RESULTS Although causality is unclear , heavy and dependent cannabis use is consistently associated with a high prevalence of comorbid psychiatric disorders and learning and memory impairments that seem to recover after a period of abstinence .
Evidence regarding other cognitive domains and neurological consequences including cerebrovascular events is limited and inconsistent .
Abstinence after treatment is only achieved in a minority of cases ; treatment targeted at reduction in use appears have some success .
Potential moderators of the impact of CUD on the brain include age of onset , heaviness of use , CUD severity , the ratio of ∆9-tetrahydrocannabinol to cannabidiol , and severity of comorbid disorders .
Current evidence of long-term effects of daily cannabis use and cannabis use disorder on brain-related outcomes is suggestive rather than conclusive but use is associated with psychiatric morbidity and with cognitive impairments that recover after a period of abstinence
AIMS To summarize and evaluate our knowledge of the relationship between heavy cannabis use , Cannabis Use Disorder ( CUD ) , and the brain .