A recent study found that when states adopted recreational cannabis laws, admissions for mental health treatment fell.
The study, published in the journal Economic Health, has come to prominence due to growing questions about the effects of cannabis on mental health. In the last two decades, many states have legalized the use of cannabis for adults. Unfortunately, research on how cannabis affects mental health is mixed.
Some studies have found that cannabis can help with certain mental health conditions, while others suggest the potential for cannabis to worsen certain conditions. Because of this complex picture, some worry that legalizing cannabis could lead to worse mental health for the general population.
This study, however, suggests that a more positive outcome comes shortly after recreational cannabis laws—less admissions for mental health treatment.
Cannabis Laws And Mental Health
Until recently, there was little research on how cannabis laws affect mental health. But Alberto Ortega, a researcher from Indiana University, Bloomington, wants to know more. “Recreational marijuana laws continue to be popular, but the effects of treatment on mental health are unclear,” Ortega explained. This prompted him to investigate whether the growing number of states with legal cannabis are seeing more positive effects.
To do this, Ortega analyzed data on mental health admissions from the Mental Health Facility’s Uniform Reporting System. It includes data on patients aged 13 to 65, over 12 years from 2007 to 2019. During this time, 10 states passed recreational cannabis laws. By comparing state-by-state data, in the years before and after voters adopted the new laws, Ortega found a clear pattern. Shortly after a state adopted the legalization of cannabis, they experienced a significant decrease in mental health treatment admissions.
These results proved robust even when he controlled for differences between states with cannabis laws and those without. For example, states that pass recreational cannabis laws tend to have broader access to Medicaid, as well as pre-existing medical cannabis laws. Because these factors can also affect mental health, Ortega controlled for them in his analysis. He also included controls for demographics such as age, race, economics, and politics. But despite these controls, the main findings were made.
Results Vary For Some Demographics
In the first few years after a state adopts a recreational cannabis law, states experience a 37% decrease in mental health admissions, on average. The results remained fairly constant for all ages under 65, even the youngest group (13-20), which saw reductions in admissions. The correlation also proved to be relatively consistent between men and women, who experienced a 42% and 37% reduction in admissions, respectively.
Race drives the biggest difference in results. Black mental health admissions fell 27%, compared to a 9% decline among whites. However, other racial demographics show less consistent results. Why does one race report fewer admissions than another? We need more research to understand this connection and what might be causing it.
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Medicaid enrollees also experienced greater outcomes. However, this may result from reporting facilities with high numbers of Medicaid users. However, both groups saw a decrease in admissions following the legalization of cannabis.
Results Show Lower Admissions, Not Better Mental Health
You can interpret this study as showing the benefits of cannabis directly helping individuals’ mental health—and thus leading to fewer mental health admissions. But as Ortega explained, “the pathways that contribute to the reduction in treatment admissions remain unclear. Therefore, the results should not be confused with good mental health.”
Future research should address the reasons for the link. Because many different theories can explain the data. Cannabis can directly help mental health. But it’s also possible that self-medicating with cannabis prevents someone from seeking help, without actually improving their mental health. Unknown factors may also account for these results.
A major limitation of this study: it does not tell us who used cannabis, and how their mental health was. It only looks at large trends at the population level. It cannot replace medical research looking at the mental health consequences of cannabis use. Ortega reminded us that his findings, “specifically speak to treatment admissions and should not be taken to improve or decrease mental health.” However, in terms of the immediate impact of legalizing cannabis on the health system – the results are clear: Legal cannabis leads to less acceptance of mental health.