Natural outcome of cannabis use disorder: a 3-year longitudinal follow-up.

Aims To assess the prevalence and correlates of remission from cannabis use disorders (CUDs), focusing on the proportion of individuals with CUDs that remit without abstaining from cannabis use. Design Three-year longitudinal study. Setting Wave 1 (2001) and wave 2 (2004) of the National Epidemiologic Survey on Alcohol and Related Conditions (NESARC), a nationally representative sample of US adults aged 18 years and over. Participants Our sample included 444 individuals diagnosed with DSM-IV cannabis abuse and/or dependence during the 12 months prior to wave 1 of the NESARC. Measurements Baseline socio-demographic and clinical correlates were analysed for possible outcomes of CUDs after 3 years: abstinent remission, non-abstinent remission and sustained disorder. Findings Approximately two-thirds (67%) of individuals with baseline CUD remitted at follow-up. Approximately 37% of those who remitted were non-abstinent. Remission was associated with Hispanic ethnicity [odds ratio (OR) = 2.59; 95% confidence interval (CI) = 1.27–4.87], baseline daily or almost daily use of cannabis (OR = 1.91; 95% CI = 1.15–3.16), baseline use of other drugs (OR = 1.63; 95% CI = 1.04–2.56) and two or more medical conditions at baseline (OR = 8.40; 95% CI = 2.67–26.41). Non-abstinent remission was associated with baseline daily or almost daily use of cannabis (OR = 1.92; 95% CI = 1.05–3.51). Conclusions A substantial level of remission from cannabis use disorders (CUDs), including non-abstinent remission, suggests that the nature of CUDs may be more unstable than reported previously.