Researchers discover that treating health problems with medical marijuana could lead to the development of cannabis use disorder (CUD).
A new study, carried out by Massachusetts General Hospital, found that medical marijuana products that treat pain, anxiety and depression failed to improve these symptoms and consequently, doubles the risk of developing the addictive symptoms of cannabis use disorder.
Cannabis use disorder is a diagnosed condition concerning marijuana use. Data indicates that it roughly affects around 10% of the 193 million cannabis users globally.
The study was published in JAMA Network Open.
Cannabis use disorder and medical marijuana
Medical marijuana has now been commercialised for use in 36 states and the District of Columbia (as of December 2021) for a range of health conditions through medical marijuana cards. To receive one of these cards, a licensed physician must provide written approval, who typically is not the patient’s primary care provider, but a ‘cannabis doctor’ who may offer authorisation to patients with only a cursory examination. They may not provide recommendations for alternative treatments and no follow-up.
The trial began in 2017 with 269 adults with an average age of 37 from the greater Boston area who were interested in obtaining a medical marijuana card. One group was given a medical marijuana card immediately and the second ‘control’ group were asked to wait for 12-weeks before obtaining a card. Both groups were tracked over the 12-weeks.
“There have been many claims about the benefits of medical marijuana for treating pain, insomnia, anxiety and depression, without sound scientific evidence to support them,” commented lead author Jodi Gilman, PhD, with the Center for Addiction Medicine at MGH. “In this first study of patients randomised to obtain medical marijuana cards, we learned there can be negative consequences to using cannabis for medical purposes. People with pain, anxiety or depression symptoms failed to report any improvements, though those with insomnia experienced improved sleep.”
Particularly disturbing to Gilman was the fact individuals with symptoms of anxiety or depression – the most common conditions for which medical cannabis is sought – were most vulnerable to developing cannabis use disorder. Cannabis use disorder symptoms include the need for more cannabis to overcome drug tolerance and continued use despite physical or psychological problems caused by cannabis.
The findings
The team found that the odds of developing cannabis use disorder was nearly two times higher in the medical marijuana card group, compared to the second ‘control’ group. By week 12, 10% of the medical marijuana group had developed a cannabis use disorder diagnosis, with that number rising to 20% in those seeking a card for anxiety and depression.
“Our study underscores the need for better decision-making about whether to begin to use cannabis for specific medical complaints, particularly mood and anxiety disorders, which are associated with an increased risk of a cannabis use disorder,” said Gilman.
Regardless of the specific health condition for which cannabis is sought, Gilman believes that regulation and distribution of cannabis to people with medical marijuana cards must be greatly improved.
“There needs to be better guidance to patients around a system that currently allows them to choose their own products, decide their own dosing, and often receive no professional follow-up care.”
