cannabis and depression: are people with depression more likely to use cannabis?
The era of reefer madness has ended. The war on drugs has been exposed as a political stunt. The US is slowly legalizing recreational cannabis, one state at a time. One of the many downfalls of the anti-cannabis era was the suspension of clinical research. Scientists were not permitted to explore the potential therapeutic qualities of cannabis, as well as all the other drugs considered illegal. As these restrictions have been lifted, a body of knowledge has begun to grow. A question of great interest: how does cannabis relate to depression?
Depression and Odds of Cannabis Use
Researchers sought out to understand the relationship between depression and odds of cannabis use. Primarily, they wanted to know if cannabis use habits differed between depressed and non-depressed individuals.
Source: Association of Depression With Past-Month Cannabis Use Among US Adults Aged 20 to 59 Years, 2005 to 2016
In sum, individuals with depression had an increased odds of cannabis use compared to the general population. Specifically, depressed individuals were more likely to have used cannabis in the last 30 days and even the last 24 hours. Next, researchers compared the odds ratios of these groups from 2005-2006 and 2015-2016. The goal of this analysis was to identify changes in the relationship over time.
The odds ratio for depression and any past-month cannabis use increased from 1.46 (95% CI, 1.07-1.99) in 2005 to 2006 to 2.30 (95% CI, 1.82-2.91) in 2015 to 2016.
In 2005-2006, depressed individuals were 46% more likely to use cannabis compared to the general population. Today, they are more than twice as likely to be using cannabis. These results suggest that a higher proportion of individuals with depression are using cannabis over time. The authors put forward the idea that more depressed individuals are self-medicating and that this practice may be reinforced by media and advertising.
The odds ratio for depression and daily or near-daily past-month cannabis use increased from 1.37 (95% CI, 0.81-2.32) in 2005 to 2006 to 3.16 (95% CI, 2.23-4.48) in 2015 to 2016.
In 2005-2006, depressed individuals were no more likely to use cannabis daily than the general population. Not only did the odds increase in 2015-2016, but so did the strength of the relationship. This is strong evidence supporting the relationship between depression and cannabis use. However, there are still many unanswered questions. Notably, we do not know the directionality of the relationship. Are depressed individuals drawn to cannabis? Does cannabis worsen depressive symptoms? These questions are complex and personal.
The data suggests that people with depression are more likely to use cannabis than the general population. It also states that these odds have magnified over time. A lot has changed in the last decade. Though cannabis is still illegal under federal law, the majority of states allow medicinal use. In 2012, Colorado and Washington became the first two states to legalize the recreational use of cannabis and a number of other states have followed in their footsteps. The increased access may contribute to the increased odds of cannabis use in the depressed population. However, it does not examine what draws depressed individuals to cannabis at higher rates than the general population. Other factors must be at play that changed how people cope with depressive symptoms.