Heavy cannabis users seeking treatment - Prevalence of psychiatric disorders

Aims The aim of this study was to estimate the prevalence of psychiatric disorders among 1439 heavy cannabis users seeking treatment for abuse problems in Denmark. Design Using two different registers, we compared cannabis users with 9122 abusers of other substances. Findings (1) Cannabis users were younger and more often males, but otherwise demographic data suggested that the group was as marginalized as users of hard drugs. (2) Additional abuse of other substances was common. (3) Even though cannabis users were generally young, 27.5% had at some point been inpatients at psychiatric hospitals with disorders unrelated to psychoactive substance abuse. (4) Cannabis users had significantly raised levels of depression (p<0.001) and personality disorders (p<0.0001) compared with users of other drugs, while the prevalence of schizophrenia was marginally raised (p<0.05). The results were obtained after adjustment for age, gender and secondary abuse. Analyses were made using logistic regression methods. Conclusion Co-morbid psychiatric disorders are common among heavy cannabis users seeking treatment. Some psychiatric disorders occur more frequently in this group compared with users of other substances.