Is there a Connection Between Cannabis Consumption and Mental Health?

With an increase in cannabis use among those who are 15 years old and older, there has been a closer look at the relationship between mental health disorders and regular or heavy cannabis use. Regular cannabis use is at least twice as common in those who have mental disorders, though the concern is that regular cannabis use can make someone more susceptible to mental health issues or cause current mental health issues to worsen over time.

No Prior History or Family History

In individuals who have no prior history and no family history of mental health disorders, the risk for developing one is low. However, the risk may be increased if someone starts using cannabis when younger, if they are a heavy or daily user, or if they use products that have higher than normal THC content. Cannabis use, even with those who have no prior history, can increase the risk of depression, suicide, and other mental health disorders, though this is not something that occurs frequently.

Prior History or Family History

It is not likely that someone even with a family history will develop anxiety as a result of cannabis use. However, those who do have a prior history of mental health disorders are more likely to use cannabis to self-medicate, which can increase their risk of developing a cannabis use disorder. This includes anxiety and related mental health disorders. There is also a higher risk for developing psychosis and schizophrenia for those who use cannabis and have a family history of these mental disorders. More studies are being done to see the exact link between prior mental health disorders and cannabis use to determine how much of an impact the cannabis use may have.

Cannabis Use Disorder

Cannabis use disorder has been listed in the DSM-5 since 2013 and is an increased concern for those who use cannabis regularly or heavily. This mental disorder is defined as a pattern of use that leads to significant impairment or distress. Those diagnosed with this tend to use cannabis more than they intend and are unsuccessful at controlling the use. They may spend a significant amount of time using cannabis or recovering from the effects, have a strong desire to use cannabis, and have issues with work, home, or school because of the cannabis use. They also may continue using despite the issues caused by the use, have an increased tolerance for cannabis, and can suffer from withdrawal symptoms. In a recent study, around 57% of regular cannabis users were diagnosed with cannabis use or met the criteria but did not have a diagnosis.

Depression

Depression is a collection of disorders that include a persistent depressed mood or lack of pleasure in most activities. There is a low risk of those who use cannabis heavily developing depression or having suicidal thoughts, though the risk does increase some if they have a family history of depression or suicide. Studies have shown a strong link between cannabis use disorder and depression in early adolescence and late adulthood. This works both ways, as those who have cannabis use disorder have a higher chance of having depression, and those who use cannabis regularly while they are depressed have a higher chance of developing cannabis use disorder.

Anxiety Disorders

Several recent studies have found a relationship between cannabis use and anxiety. Those who use cannabis regularly were more likely to have symptoms of anxiety, especially if they started using cannabis before they were 15 years old. The risk of developing anxiety from cannabis use is small, though the severity of the anxiety can differ for each person. Those who do develop anxiety, regardless of whether it’s connected to cannabis use, and who continue to use cannabis while suffering from anxiety may tend to use cannabis to self-medicate. This can lead to the development of cannabis use disorder.

Schizophrenia and Related Disorders

Cannabis use and the development of cannabis use disorder is higher amongst those who have schizophrenia, and there is substantial evidence that shows that the use of cannabis can lead to an increased occurrence of schizophrenia and related disorders. Some studies have found that using cannabis can increase the risk of psychosis and related disorders by around 40%. Those who have been diagnosed with cannabis use disorder are at a higher risk of developing schizophrenia and related disorders, more so than those who are addicted to alcohol or cocaine. The risk is heightened by a family history of mental illness, the amount and frequency of cannabis use, and other factors like the age when they started using cannabis. Those who start using cannabis when they are younger or who frequently use cannabis with higher THC content are more likely to develop a psychotic disorder like schizophrenia.

Bipolar Disorder

So far, there has been limited research on the relationship between bipolar disorder and cannabis use. However, those with bipolar disorder are more likely to use cannabis regularly as self-medication, which means they are more likely to develop cannabis use disorder. Cannabis use in those who have bipolar disorder can cause more severe symptoms and lengthen the duration of manic phases. More studies are needed in this area, but they have shown that cannabis use could be linked to the first episode of bipolar disorder as well as lead to worse symptoms.

Cannabis use in and of itself has a low risk of causing mental disorders in those with no personal or family history, though even those with no prior history do have a high chance of developing cannabis use disorder. In those who do have a personal or family history of mental disorders, the risk for worsening symptoms is increased with cannabis use, and many who have a family history may develop mental health disorders with regular or heavy cannabis use. More studies are needed to determine exact relationships between cannabis use and mental health disorders, but there is a reason to exercise caution for those who already suffer from mental health issues or who may be at risk of developing one.