Use and diversion of medical marijuana among adults admitted to inpatient psychiatry.

BACKGROUND: Marijuana use is associated with anxiety, depressive, psychotic, neurocognitive, and substance use disorders. Many US states are legalizing marijuana for medical uses.
OBJECTIVE: To determine the prevalence of medical marijuana use and diversion among psychiatric inpatients in Colorado.
METHODS: Some 623 participants (54.6% male) responded to an anonymous 15-item discharge survey that assessed age, gender, marijuana use, possession of a medical marijuana card, diversion of medical marijuana, perceived substance use problems, and effects of marijuana use. Univariate statistics were used to characterize participants and their responses. Chi-square tests assessed factors associated with medical marijuana registration.
RESULTS: Of the total number of respondents, 282 (47.6%) reported using marijuana in the last 12 months and 60 (15.1%) reported having a marijuana card. In comparison to survey respondents who denied having a medical marijuana card, those respondents with a medical marijuana card were more likely to have initiated use before the age of 25, to be male, to have used marijuana in the last 12 months, and to have used at least 20 days in the past month. 133 (24.1%) respondents reported that someone with a medical marijuana card had shared or sold medical marijuana to them; 24 (41.4%) of respondents with a medical marijuana card reported ever having shared or sold their medical marijuana.
CONCLUSION: Medical marijuana use is much more prevalent among adults hospitalized with a psychiatric emergency than in the general population; diversion is common. Further studies which correlate amount, dose, duration, and strain of use with particular psychiatric disorders are needed.