The Link Between Cannabis Use Disorder and Mental Illness

Cannabis is one of the most widely used drugs in the world, and its use as a recreational drug has been enhanced by widespread legalization for personal use. However, cannabis use is not without risks, and the risk of developing a cannabis use disorder (CUD) is in the 10-15 percent range for regular users. CUD can affect not only physical health, but also mental health and it appears that adolescent youth and young adults are particularly vulnerable as described in a recent large-scale study from Denmarkreporting an increased risk of psychotic and nonpsychotic bipolar disorder and unipolar depression in cannabis users who start using at an early age.

What is the study about?

The study, published in JAMA Psychiatry, is one of the largest of its kind, involving more than six million Danes born between 1970 and 2000. The researchers used national registers to identify individuals with CUD and those with mental disorders, such as schizophrenia, bipolar disorder, unipolar depression, anxiety disorders, and personality disorders. They also adjusted for potential confounders, such as gender, age, socioeconomic status, family history of mental disorders, and other substance use disorders.

The researchers followed the participants from their 15th birthday until the end of 2016, and calculated the risk of developing a mental disorder after being diagnosed with CUD. They also compared the risk of CUD among those with and without a mental disorder.

What are the main findings?

The main findings of the study are:

• CUD was associated with an increased risk of psychotic and nonpsychotic bipolar disorder and unipolar depression in both men and women.
• The risk was higher for psychotic bipolar disorder than for nonpsychotic bipolar disorder or unipolar depression.
• The risk was higher for those who were diagnosed with CUD at a younger age or who had a longer duration of CUD.
• CUD was also associated with an increased risk of schizophrenia, anxiety disorders, and personality disorders, but these associations were weaker than those for bipolar disorder and unipolar depression.
• Individuals with a mental disorder had a higher risk of developing CUD than those without a mental disorder.

What are the implications?

The study provides evidence that CUD is linked to an increased risk of developing bipolar disorder and unipolar depression. These findings have important implications for public health, especially as legaled recreational use is becoming widespread. The researchers emphasize that their study does not prove that cannabis use causes these mental disorders, as there may be other factors involved, such as genetic predisposition or self-medication. However, they suggest that cannabis use may trigger or worsen these conditions in some individuals who are vulnerable to them.

The researchers also call for more research to understand whether cannabis has particularly harmful effects on certain subgroups of users, such as those with a family history of mental disorders or those who use high-potency cannabis products. This could help inform policies and prevention strategies related to cannabis use and legalization.

If you would like to discuss your cannabis use with a qualified mental health professional, please schedule an appointment at CARMAhealth by calling 512-212-4670 or visit us at https://carmahealth.com/locations