Comorbidity with psychiatric disorders, including anxiety disorders and DSM-IV antisocial personality disorder, except for posttraumatic stress disorders (PTSD), surprisingly, did not differ across groups. PTSD had a significantly higher rate in comorbid vs. non-comorbid individuals at baseline and comorbid CUD and bipolar I subjects at follow-up. Subjects with PTSD may, therefore, more often use and abuse cannabinoids to cope with their symptoms cf., anxiety, sleep disorders and intrusions. A recent small randomized controlled trial (RCT) using medical cannabis (nabilone) to treat PTSD found that nabilone significantly reduced the severity of PTSD-related nightmares [36]. Participants also reported significant improvements on secondary measures of general well-being and mean global improvements.
