Need for Weed Takes Its Toll

Marijuana dependent users had higher rates of mental health disorders than others

/ Author:  / Reviewed by: Chris Galloway, M.D.

(RxWiki News) People that are dependent on marijuana may be using it to cope with a mental health disorder. Masking mental illness with weed can turn into dependence.

A recent study looked at the rates of mental health issues in frequent marijuana users, compared to the general population.

The results of this study showed that people who were dependent on marijuana were more likely to have a mental health issues, as compared to people who were not dependent.

"Call a therapist for any addiction."

Peggy van der Pol, PhD student, an epidemiologist from the Trimbos Institute at the Netherlands Institute of Mental Health and Addiction, led a team to investigate mental health disorders in people who use marijuana.

While marijuana may not be known to have the same addiction potential associated with substances like heroin and cocaine, clinical dependence is still possible.

Marijuana dependence has the characteristics of other substance use disorders.  Marijuana-dependent people may develop an increasing tolerance over time and may experience withdrawal symptoms if they stop using marijuana.  Also, marijuana dependence can get in the way of work or social life.

For this study, 521 young adults, between the ages of 18-30, that used marijuana on a regular basis (3 or more days per week) were evaluated for mental health disorders and troubled childhoods.

The researchers also did the same evaluations for 1,072 people in the general population, who did not frequently use marijuana, to compare results from the two groups. In the marijuana group, 252 were diagnosed with symptoms of marijuana dependence, while 269 were not found to be dependent.

The results of the study showed that dependent marijuana users had 15 times higher odds, and non-dependent marijuana users had 5 times higher odds, of having a mental health disorder compared to those in the general population.

Dependent marijuana users had both externalizing and internalizing disorders, whereas non-dependent users had mostly externalizing disorders. The authors noted that the higher rate of externalizing disorders in non-dependent users was largely due to childhood externalizing disorders.

Externalizing disorders involve acting out and include: attention deficit/hyperactivity disorder (ADHD), conduct disorder and oppositional defiant disorder.

Internalizing disorders involve more mood-oriented symptoms and include: depression, anxiety disorders and obsessive-compulsive disorder.

Dependent and non-dependent cannabis users did have similar habits, but dependent users tended to use marijuana when they were alone and as a coping device more so than non-dependent users.

After making adjustments, the authors concluded that marijuana dependent users were 2.5 times more likely to have a mental health disorder than non-dependent users.

The authors said that the self-reporting nature of this study could be considered a limitation. Participants may have chosen to hide key information that could have skewed results.

The authors concluded that mental health risks in frequent, non-dependent marijuana users may have been overestimated in previous studies. Authors continued that non-dependent users could still be at risk for becoming marijuana dependent.

This study was published in March in Addiction.

The Netherlands Organisation for Health Research and Development supported the funding for this project. No conflicts of interest were declared.

Reviewed by: 
Review Date: 
March 29, 2013
Last Updated:
April 1, 2013