The use of cannabis was associated with lower rates of subjective cognitive decline (SCD), according to the findings of a new study from researchers affiliated with the State University of New York (SUNY). The research found that participants who use marijuana for recreational or medicinal purposes reported less confusion and memory loss compared to those who do not use weed.
The new study, which was published online last month by the journal Current Alzheimer Research, found that recreational cannabis use had the most significant impact on cognitive decline.
“Compared to non-users,” the authors wrote, “non-medical cannabis use was significantly associated with 96% decreased odds of SCD,” according to a report from Filter.
People who used cannabis for medicinal reasons or for both recreational and medical purposes also showed “decreased odds of SCD.” However, the differences did not rise to the level of statistical significance.
The authors of the study note that previous research has found a link between heavy cannabis use and cognitive performance. Past studies have shown that frequent or heavy marijuana use was associated with lower verbal recall performance, subjective memory complaints and lower cognitive function, among other signs of mental decline.
“However, the cognitive implications of cannabis are not only determined by the frequency of cannabis consumption,” the researchers wrote, adding that other factors including the particular product used, method of consumption, and reason for use could also “impact the cognitive effects associated with cannabis use.”
“Our study addresses these knowledge gaps by comprehensively examining how reason, frequency, and method of cannabis use are associated with SCD among US middle-aged and older adults,” the authors of the study added.
To conduct the study, researchers at SUNY Upstate Medical University in Syracuse, New York analyzed health survey data from the 2021 Behavioral Risk Factor Surveillance System (BRFSS). The researchers note that the system’s cognitive decline model “was restricted to respondents aged 45 years and older in Washington DC and 14 US states (GA, HI, MS, OR, PA, TN, TX, WI, CO, MD, MI, OH, OK, and NY).”
The total sample included 4,744 observations with valid SCD responses.
Survey Asked About Memory Lapses And Confusion
The survey asked respondents, “During the past 12 months, have you experienced confusion or memory loss that is happening more often or is getting worse?” Respondents were given the option to reply yes, no, don’t know/not sure, or to refuse the question.
The researchers analyzed the survey data based on three cannabis variables including frequency of use over the past month, ranging from zero to 30 days; reason for cannabis use, which included non-user, medical, non-medical or both; and the method of cannabis consumption, such as non-user, smoke, eat, drink, vaporize, dab or other.
“We found that non-medical cannabis use was significantly associated with reduced odds of SCD in comparison to non-users,” the researchers wrote, adding that there are several possible reasons for the study’s findings.
The researchers offered several possible reasons that could explain why cannabis use was associated with reduced rates of self-reported cognitive decline. They note that many people use cannabis to help them sleep, citing a recent study that found that “more frequent sleep disturbances were associated with higher dementia risk in a national US older adult sample.”
“Several studies have found that cannabis use might enhance sleep quality, expedite sleep onset, and reduce sleep disturbances. Non-medical cannabis use could have contributed to the observed decrease in SCD due to its potential benefit on sleep quality,” the discussion section of the new paper said.
The results of the study were not consistent for some variables, however. Researchers found an association between the method of cannabis consumption, including a higher prevalence of SCD among cannabis smokers. The research also found an association between the frequency of use and cognitive decline.
“Although increased frequency and different methods of cannabis use showed positive associations with SCD, these relationships were not statistically significant.”
The researchers stressed that the study does not refute previous research that has shown frequent or heavy marijuana use was associated with cognitive decline. Instead, they said that the mixed findings indicate the need for further research on the subjects.
“Our findings underscore the importance of considering multiple factors, such as the reasons for cannabis use, when examining the relationship between cannabis and SCD,” the authors wrote in their conclusion. “Further research is needed to explore the underlying mechanisms contributing to these associations.”
The authors noted several limitations to the study, including a reliance on self-reported data. They also reported possible bias in responses from participants in states that have not legalized medical cannabis, noting that “individuals in such states may be more likely to underreport or misreport their cannabis use.”
The study was published as an “article in press,” indicating that it has been accepted by the journal and copyedited and formatted for publication. Further corrections or proofreading changes could come before the article’s final version is published.
