The number of states that have approved marijuana for PTSD treatment is on the rise, but a new study shows that it may actually worsen symptoms, according to Samuel T. Wilkinson, MD, of the Yale University School of Medicine in New Haven, Connecticut, and colleagues.
The observational study included 2,276 participants who had been admitted to specialized Veterans Administration treatment programs for PTSD between 1991 and 2011. Participants were split into four groups: 831 who started taking marijuana (“starters”), 850 who never used marijuana (“never used”), 296 who used marijuana at admission and after discharge (“continuing use”), and 299 who stopped using marijuana after treatment (“stoppers”).
Each participant was evaluated at admission and four months after discharge, with measurements taken using the short version of the Mississippi Scale (MISS) to evaluate PTSD symptom severity, the drug and alcohol subscales of the Addiction Severity Index (ASI), and reports of violent behavior.
Those in the “never used” group had significantly lower MISS scores than those in the “starters” and the “continuing use” groups, the researchers reported at the recent American Academy of Addiction Psychiatry meeting. The “stoppers” had significantly lower MISS scores at follow-up than they did at baseline. Those in the “starters” group also had the highest level of violent behavior and the highest ASI scores. The “stoppers” group had significantly lower ASI scores than the other three groups.
Although a growing number of states have approved post-traumatic stress disorder (PTSD) as a qualifying condition for medical marijuana use, new research shows that the drug may actually worsen symptoms and increase violent behavior.
A large observational study of more 2000 participants who were admitted to specialized Veterans Administration treatment programs for PTSD showed that those who never used marijuana had significantly lower symptom severity 4 months later than those who continued or started use after treatment. Veterans who were using marijuana at treatment admission but quit after discharge (“stoppers”) also had significantly lower levels of PTSD symptoms at follow-up.