ABSTRACT
Background
Multiple states have authorized cannabis as an opioid substitution agent and as a treatment for posttraumatic stress disorder (PTSD).
Objectives
This study sought to investigate the relationship between cannabis use, non-medical opioid use, and PTSD symptoms among U.S. veterans.
Methods
From 1992–2011, veterans admitted to specialized intensive PTSD treatment participated in a national evaluation with assessments at intake and four months after discharge. Participants with non-medical opioid use ≥ 7 days during the 30 days preceding admission were divided into two groups: those with cannabis use ≥ 7 days, and those without cannabis use. These two groups were compared on measures of substance use and PTSD symptoms at baseline and 4-months outpatient follow-up. We hypothesized that, at both assessments, the group with baseline cannabis use would show less non-medical opioid use and less severe PTSD symptoms.
Results
Of 1,413 veterans with current non-medical opioid use, 438 (30.3%) also used cannabis, and 985 (69.7%) did not. At baseline, veterans with concurrent non-medical opioid and cannabis use had slightly fewer days of non-medical opioid use (p < .005; d = −0.16), greater use of other substances (p < .0001) and more PTSD symptoms (p = .003; d = 0.16), compared to veterans who used non-medical opioids but not cannabis. At follow-up, substance use or PTSD symptoms did not significantly differ.
Conclusion
Cannabis use was not associated with a substantial reduction of non-medical opioid use, or either improvement or worsening of PTSD symptoms in this population. Hence, these data do not encourage cannabis use to treat either non-medical opioid use or PTSD.
Disclosure
The authors report no potential conflict of interest.
Additional information
The VA New England Mental Illness Research and Education Center, West Haven, CT manages The Intensive PTSD VA Treatment database, which is stored in secure VA servers and is not available to the public. Queries can be directed to Robert Rosenheck, M.D. ([email protected]).