Marijuana, PTSD treatment data is insufficient, say researchers
Washington Times - 8/15/2017
Two medical studies published Monday in a peer-reviewed journal conclude that there is insufficient data from previous research to evaluate the benefits of medical marijuana in treating chronic pain and post traumatic stress disorder.
But the studies' researchers, who work in the Department of Veterans Affairs, are barred from commenting about their findings because the drug is illegal under federal law.
The VA researchers' studies were published in the Annals of Internal Medicine.
In an accompanying editorial, Dr. Sachin Patel of the Vanderbilt Psychiatric Hospital said the studies "highlight an alarming lack of high-quality data from which to draw firm conclusions about the efficacy of cannabis for these conditions, for which cannabis is both sanctioned and commonly used."
Both studies reviewed previous research evaluating the effectiveness of cannabis and cannabis products in treating physical and psychological disorders.
Researchers often have expressed frustration over the lack of so-called "gold-standard" testing in medical marijuana studies — that is, randomized clinical trials.
"Given how debilitating PTSD can be — high rates of suicide, etc. — anything we can do to help folks that are suffering, especially if it has minimal risk, I think deserves further examination," said Zachary Walsh, a researcher who did not work on the VA studies.
An associate professor of psychology at the University of British Columbia, Mr. Walsh is the lead author of a February study that also reviewed previous medical marijuana research and its effects on PTSD. He concluded there is strong preliminary evidence that it can be helpful but that clinical trials are needed.
"Given the very acceptable risk profile of cannabis and the lack of good treatments for PTSD, I think it's a very promising therapy. There's great potential benefit and low potential risk relative to other treatments," he said.
Patients who replace a cocktail of medications with cannabis to treat PTSD "report tremendous success," Mr. Walsh said.
"If it's not effective, then people can just stop using the cannabis. And we do need the clinical trials and those are underway. So I think in a few years we'll know a whole lot more," he added.
Medical marijuana is legal in 28 states, and recreational pot is legal in eight states and the District of Columbia, even though the drug remains illegal under federal law.
The VA study led by Shannon Nugent looked at research evaluating the effects of cannabis on adults with chronic pain.
"Limited evidence suggests that cannabis may alleviate neuropathic pain in some patients, but insufficient evidence exists for other types of chronic pain. Among general populations, limited evidence suggests that cannabis is associated with an increased risk for adverse mental health effects," Ms. Nugent and colleagues wrote in their conclusion.
The other VA study, led by Maya O'Neil, focused on the effects of marijuana treating PTSD via searches of ongoing studies and a review of existing evidence. In their introduction, the researchers highlighted that one-third of patients seeking medical marijuana do so to treat PTSD.
"Evidence is insufficient to draw conclusions about the benefits and harms of plant-based cannabis preparations in patients with PTSD, but several ongoing studies may soon provide important results," Ms. O'Neil and colleagues wrote in their conclusion.
A VA spokesperson referred inquiries on Monday to past statements by Veteran Affairs Secretary David Shulkin.
In comments at a White House press conference in May, Mr. Shulkin acknowledged the potential benefits of medical marijuana, but said his department is restricted from prescribing marijuana because of federal laws.
"My opinion is, is that some of the states that have put in appropriate controls, there may be some evidence that this is beginning to be helpful," Mr. Shulkin said. "And we're interested in looking at that and learning from that. But until the time that federal law changes, we are not able to be able to prescribe medical marijuana for conditions that may be helpful."