Tags: cannabis, marijuana, education/communications, effectiveness, risk factors

 

The problem: People use cannabis to treat a variety of medical issues, and many consider it to be superior to traditional pharmaceutical drugs. However, these beliefs are not always in line with legal policies or empirical evidence. There is strong evidence that cannabis is effective in treating some conditions, but very limited evidence for the treatment of others. It is unclear whether people turning to cannabis for the management of medical treatments are accurately aware of the proven effectiveness and/or risks of cannabis use.

 

Why do this study? This study was done to compare cannabis users’ knowledge about risks and medicinal effectiveness to existing empirical evidence.

 

The study: This study analyzed data collected from a survey that was conducted at a cannabis advocacy event, in a state where medical and recreational cannabis is legal. Survey participants were asked about their personal cannabis use, where they obtained information about cannabis, what conditions they thought cannabis was effective in treating and what risks cannabis poses. These responses were compared to the official conclusions drawn by the National Academy of Science, Engineering and Medicine (NASEM) based on empirical studies. Most participants cited their own experiences as their main source of cannabis knowledge, followed by the internet, advice from friends/family, medical cannabis dispensary, primary care providers, and lastly, books and journal articles. Most participants reported using cannabis every day, and most of them used it for medical reasons.

            Participants’ beliefs of effectiveness/risks of cannabis matched those of NASEM about half the time, on average. Most respondents believed cannabis use is effective in treating adverse effects of chemotherapy, chronic pain, and irritable bowel syndrome, which matches NASEM conclusions. In contrast, the majority thought that cannabis was effective in treating cancer, depressive symptoms, and epilepsy, which does not match NASEM review. Those who reported learning cannabis information from their primary care provider had a better knowledge of medical effectiveness, but not of increased risks. Among respondents, those who reported more frequent cannabis use were less well informed about risks.  Compared to NASEM conclusions, based on existing research, survey participants over estimated the medical effectiveness and underestimated the risks of cannabis use.

 

Conclusions: This study concludes that there are considerable discrepancies between what cannabis users believe about effectiveness/risks of cannabis use for treating medical conditions, and what empirical evidence has proven. This tells us that many of the people using cannabis for medical treatments are often not well informed about the factual benefits/risks of cannabis use.

 

What does this study add?  This study highlights the need for more research and education (by those dispensing both profession medical advice and those dispensing cannabis) about the risks and effectiveness of cannabis use. This is particularly relevant for users with health issues for which cannabis may be a treatment option.

 

Funder: None

 

Author conflicts: None

 

Commentary: (Kelly Hughes and David Casarett)

A skeptic would look at these results and conclude that many cannabis users are blind to the real science about its benefits, and in denial regarding its risks.  That’s a fair assessment, and certainly some skepticism about the benefits and risk fo cannabis are appropriate.  The considerable discrepancies between what cannabis users believe and what the medical community has proven shows the need for better dissemination of information beyond the medical/research community. Better communication is central to effectively informing the public about cannabis use, to maximize the benefits and minimize the harm and risk. That’s one view.

On the other hand, it’s possible to read an entirely different message from this study—that patients see benefits that science hasn’t yet discovered.  This is a fair assessment, too, especially since research (at least in the US) has been curtailed by legal hurdles.  So just because there haven’t been good studies demonstrating a benefit, that doesn’t mean that this evidence doesn’t exist; just that we haven’t found that evidence yet.

So what’s the correct interpretation?  Probably a little of both.  People may well have exaggerated views of the benefits of cannabis, and may downplay its risks if they have experienced those risks themselves.  However, it’s also worth thinking about the role that advocacy plays and whether a mismatch of beliefs vs. evidence is harmful to advocacy efforts.  As a physician (DC) I always try to adhere as close as I can to the evidence when I talk to my physician colleagues.  I emphasize what we don’t know, and I acknowledge what we don’t. That’s been effective for me, and I have to believe that a stricter interpretation of the evidence might help advocacy effort to be more effective.