A recent study has found that people who use cannabis and tobacco simultaneously are nearly twice as likely to develop symptoms of mental health, specifically anxiety and depression, than those who don’t.
With the aim of adding to a perceived lack of information on the association between mental health and the uses and co-use of cannabis and tobacco, researchers from the University of California analysed data from nearly 53,843 US citizens who participated in the COVID-19 Citizen Science Study.
“Studies showed that cannabis use increased over time and is 2–10 times more common among those with, versus without, cigarette smoking. These trends raise concerns about unknown harms related to cannabis use in general and co-use of tobacco and cannabis in particular. Co-use may increase exposure to toxicants and pose additive health risks”
Cannabis laws have been changing at the State level in recent years, and subsequently, the use of cannabis and the co-use of cannabis and tobacco have increased. Data shows that “In the U.S., 22.1% of adults reported using tobacco and 12.4% using cannabis in the past month in 2020. Co-use of tobacco and cannabis (defined in this study as concurrently using both substances in the past month) is also prevalent with 33% of people who use tobacco also reporting using cannabis in the past month.”
Data from previous studies shows that the use of either tobacco or cannabis can be related to poor mental health. However, this is difficult to draw firm conclusions from as people often turn to substances as a way to help deal with ongoing symptoms.
To determine if a link is present, researchers compared reported instances of anxiety and depression in those who use and co-use cannabis and tobacco with those who do not consume either.
The results showed that there was an association, particularly in those who co-use as opposed to not using either tobacco or cannabis. The authors wrote, “As hypothesized, we found that use of tobacco and/or cannabis was positively associated with self-reported anxiety and depression. Notably, co-use was associated with higher odds of anxiety when compared to tobacco-only use, but not different from cannabis-only use. We also found that daily use of cigarettes, e-cigarettes, and cannabis were associated with the increased odds of reporting anxiety and depression. To our knowledge, this is the first study among the US adult population to evaluate the association of mental health with four mutually exclusive patterns of tobacco and cannabis use, with a focus on the co-use of both substances.”
The limitations of this study included a small sample size, the data being collected online which often leads to bias, and the COVID regulations that were in place at the time of the survey being conducted all need to be considered when making conclusions from the results.