Medical cannabis doesn't cause cognitive decline in seniors, study finds

"Although the cannabis patients have been using it consistently for at least a year, we have not found that their cognitive function is lower than of people similar to them in age and background."

A worker touches a cannabis plant at a growing facility for the Tikun Olam company near the northern city of Safed (photo credit: REUTERS/NIR ELIAS)
A worker touches a cannabis plant at a growing facility for the Tikun Olam company near the northern city of Safed
(photo credit: REUTERS/NIR ELIAS)
A new study conducted at Haifa University's School of Public Health has found no evidence of cognitive decline in senior citizens who regularly smoke medical cannabis to treat chronic pain. 
Chronic pain affects 19%-37% of the adult population worldwide and medical cannabis has, in recent years, been raised by patients and researchers alike as a "highly effective" possible treatment.
According to the researchers however, most studies done to date have mainly examined the effect of cannabis use on cognitive function in young people.
"Previous studies have shown that medical cannabis can have long-term effects on the brain when consumed at a young age, but this is not necessarily the same effect when consumed in old age,"  said Dr. Sharon Sznitman and Dr. Galit Weinstein, two of the researchers who conducted the study.
"Our study is the first step in a more accurate assessment of the risk versus benefit of cannabis treatment in this population," the researchers explained.
The study involved 125 subjects, of whom 63 were medically licensed to use medical cannabis and 62 were unlicensed. The average age of the subjects was 62.
During the study, the subjects' cognitive function were tested using a series of computerized tests that evaluate the function of psychomotor responses, concentration, memory and learning abilities.
Study participants were asked to refrain from using cannabis three hours before the test so that their cognitive abilities would be tested when they were not under the immediate influence of cannabis.
"Although the cannabis patients have been using it consistently for at least a year, we have not found that their cognitive function is lower than that of people similar to them in age and background diseases," Sznitman and Weinstein said.
The study was published in the medical journal Drug and Alcohol Review and was conducted by Sznitman and Weinstein together with Dr. Simon Vulfsons from the Rambam Medical Campus and Prof. David Meiri from the Technion. 
"Our research findings may reduce concerns among physicians who deal with chronic pain and among patients suffering from it regarding the possible effects of cannabis on brain function," the researchers added.
"However, more research needs to be done to substantiate the results of the current study. The studies should include brain photographs and other ways in which cognition can be assessed," they concluded.