Many people with multiple sclerosis (MS), about two-thirds according to a recent survey, use cannabis for a variety of reasons, largely to manage pain, spasticity, depression, anxiety, insomnia and fatigue, and previous research has already suggests that memory, processing speed, and executive function improved after MS patient groups stopped using cannabis for 28 days.
But now, researchers are aiming to understand why MS patients continue to use cannabis, despite the cognitive risks.
The study “Impaired awareness: Why people with multiple sclerosis continue using cannabis despite evidence to the contrary,” published in the journal Brain and Behavior by a team of researchers in Canada.
Researchers hypothesized that patients, due to their disease, have a lesser awareness or understanding of their thoughts (called metacognition), which could partly explain the predisposition to cannabis consumption. The study enrolled 40 cognitively impaired adults with MS who were “longstanding, frequent” cannabis consumers; 20 stopped using cannabis (and one ended up leaving the study), while the other 20 continued to use it. Both groups were followed over 28 days, patients’ cognitive skills tested before and after.
People in the withdrawal group improved significantly “across multiple domains such as processing speed, learning, verbal and visual memory, and executive function,” following 28 days without cannabis. The other group showed no changes in cognitive function between the study’s start and the testing 28 days later. “Most notably, cognitive improvement was not accompanied by a self-awareness of this positive cognitive change,” the researchers say, with all 19 withdrawal group patients returning to regular cannabis use for reasons similar to those they initially relayed.
Patients using cannabis to manage depression showed a reduction in their depression scores (indicating less depression) after stopping cannabis for 28 days; those who continued had no changes.
Researchers also saw that the withdrawal group patients were less likely to partake in activities outside of their homes, and that this negative change “gives a possible clue as to why all our study participants returned to using cannabis after a month of abstinence. The ‘reward’ that comes with this recidivism is a less constrictive lifestyle, which in the context of a disabling illness like MS, cannot be underestimated,” researchers wrote.