“How many wars is the US really fighting?” blares the headline of a 2015 article. The answer, according to the author, Nick Turse, is that US Special Operations forces have already deployed to 135 nations, carrying out roles as advisors, performing secret operations, or actively engaged as the tip of the spear in war. Some of these operations have taken place in hot spots of the world like Afghanistan and Iraq. The seemingly imminent destruction of ISIS in Mosul bears testimony to the bravery and skills of all the soldiers who have taken up arms. Their victories will no doubt be cause for much relief, celebration, and national accolades for those that went above and beyond the call of duty; however, long after the fanfare and the last tweets have disappeared into the ether, some families will welcome soldiers with "invisible wounds" home. They will bear permanent mental scars of war.
The lifetime prevalence of post-traumatic stress disorder (PTSD; see video for explanation) in the general population ranges between 1.9% and 8.8% . Up to 18% of soldiers returning home from recent wars are likely to suffer from PTSD. In another 2016 NY Times article, a neuropathologist described the brain of a soldier, who had survived a suicide bombing attack, only to perish two years later from a drug overdose. If the visible brain changes that he reports are confirmed by other scientists, it would be an indication that the phenomenon first referred to as shell shock, then combat fatigue, and now PTSD, may have physical roots, rather than just being a “mental problem.”
However, for PTSD sufferers, the roots of the nightmares are less important than the havoc the unpredictable, and sometimes never-ending, loop of images in their heads wreak on their lives. Some have even speculated that PTSD may have been an additional stressor contributing to the daily suicide rate of 22 among veterans (2010 estimates). Numerous social and cognitive approaches are already being used to help patients adjust in society. Now researchers have suggested an interesting hypothesis that one may also be able to pharmacologically erase the embedded memories that can trigger trauma—at least in laboratory animals.
Here is where endocannabinoids enter the story. They speculate that endocannabinoids and glucocorticoids interact in fear memory consolidation. Researchers have proposed a feedback loop, whereby glucocorticoids could trigger endocannabinoid release to help in “fear memory extinction .”
Cannabinoids have been shown to have a range of positive effects of stress, including anti-anxiety like states, in animal models . What about people? A spate of studies and reviews have reached opposite or no conclusions. One study emphatically stated that marijuana use was associated with worse outcomes in symptom severity and violence among patients with PTSD. Another literature review found insufficient evidence to draw any conclusions at all. What researchers do seem to agree on, is that the severity of PTSD symptoms may drive sufferers to use cannabis as a coping mechanism. Most papers these days end with a phrase like this: "Large-scale randomized clinical trials are needed to establish the benefits of cannabis to patients with PTSD.” Roughly translated, the jury is still out on this one. In the meantime, patients lacking access to multidisciplinary or trauma-focused psychological care will do what they need to do in order to forget the fog of war.
1. Bisson, Jonathan I., et al. "Post-Traumatic Stress Disorder." The BMJ 351 (2015): h6161.
2. de Bitencourt, R. M., F. A. Pamplona, and R. N. Takahashi. "A Current Overview of Cannabinoids and Glucocorticoids in Facilitating Extinction of Aversive Memories: Potential Extinction Enhancers." Neuropharmacology 64 (2013): 389-95.
3. Mizrachi Zer-Aviv, T., A. Segev, and I. Akirav. "Cannabinoids and Post-Traumatic Stress Disorder: Clinical and Preclinical Evidence for Treatment and Prevention." Behav Pharmacol 27.7 (2016): 561-9.