A new study has linked cannabis to suicidal thoughts – here’s the facts

A new study has linked cannabis use to suicidal ideation – but it doesn’t look at the whole picture, say medical experts.

According to researchers from the National Institute on Drug Abuse (NIDA) cannabis consumption was associated with a higher prevalence of suicidal ideation and attempts among US young adults, with or without depression.

This was true for both sexes, but appeared to be more prevalent in women. 

The study used data from 281,650 participants of the National Surveys of Drug Use and Health (NSDUH) between 2008 and 2019.

The findings suggest that both daily and occasional cannabis use increased the risk of suicidal ideation, plan, and attempt increased from 40 percent to 60 percent over this time period.

The authors conclude that more research is needed to examine the increase in suicidality and to determine “whether it is cannabis use or overlapping risk factors that increase risks for both.”

It could be argued that these findings point to existing evidence linking cannabis use with mood disorders and self-harm, but the study failed to take into account some important factors, according to medical experts..

Dr Dani Gordon is a world leading expert in clinical cannabinoid medicine, having prescribed medical cannabis to thousands of patients.

Dr Dani Gordon has prescribed medical cannabis to thousands of patients

Studies such as these should be treated with caution, she warns, and are often erroneously used to justify blocking or restricting wider access to cannabis for medical purposes in appropriate patients.

Firstly, those in the study were using self-administered cannabis, which was not accessed through a prescription by a trained medical doctor, under medical guidance.  

So-called ‘recreational’ or self-administered, non-medical cannabis use generally contains higher levels of THC and is very different from how medical cannabis would normally be prescribed. 

This study likely has “little or no bearing” on the risks and therapeutic indications of medical cannabis, especially for those over the age of 25, says Dr Gordon. 

It was also conducted on young adults, aged 18-35, a small subset of the age group where medical cannabis tends to be most utilised.   

“In patients under the age of 25, due to possible deleterious effects on the developing brain in young people of high THC consumption, medical cannabis containing THC is used very sparingly and only when clinically necessary and when other medications have been tried first, for example, in severe epilepsy and other serious conditions that have not responded to other drugs,” she explains.

“Already this study has skewed the patient population towards more harm, especially when the cannabis is self-administered for ‘recreational’ use.”

While the NSDUH took into account sociodemographic characteristics, such as age, sex, race/ethnicity, education, employment status, family income and health insurance, it does not mention any controlls for underlying health conditions.

Previous researchers have suggested that the perception of cannabis as having a negative impact on mental health could be the result of how data has been interpreted over the years.

Psychology professor at Washington State University, Dr Carrie Cuttler, has been researching cannabis and mental health for several years. 

According to her work, the top three reasons given by patients for consuming cannabis were pain management, followed by depression and anxiety.

In a study published last year she found that people living with common mental health issues including anxiety, depression, post-traumatic stress disorder (PTSD) and obsessive compulsive disorder (OCD) reported that cannabis use had actually reduced their symptoms by more than half in the short-term.

She told Cannabis Health at the time that the correlation between cannabis use and mental health problems has been interpreted in “potentially the wrong direction.”

On top of this, mental health issues, including depression and suicide ideation are a common issue among many patients living with chronic illness, particularly those with pain conditions, who are more likely to be self-medicating with cannabis.

“Of people who use cannabis ‘recreationally’ a significant number of those people will be using it for a health related condition or symptom. A lot of the time that’s anxiety, mental health or pain of some variety, often when other conventional drug treatments have failed or been only partially successful,” explains Dr Gordon, who will open her Resilience Medicine clinic in the UK in the coming weeks. 

“Anyone who suffers from chronic pain that has been poorly treated, or neuropsychiatric symptoms and other poorly treated conditions such as chronic fatigue syndrome/ME or fibromyalgia and many women’s health symptoms are often very marginalised in the medical experience.

These patients will tell me that their experience with the medical care they have received and with the medical system in general has had a huge impact on the way they experience their illness, for example suffering more, and these experiences have also negatively impacted their mental health.

“While they may not have been actively suicidal in the past, many may have had passive suicidal ideation as a result of feeling marginalised, hopeless about their condition and their chances of getting symptom relief or feeling better.

“This hopelessness can lead to feelings of despair, although unless a doctor asks specifically about this, many patients will not offer up this information for fear of being further stigmatised. 

“That is the nature of the types of people who tend to utilise cannabis rather than cannabis causing this phenomenon.”

Dr Gordon also notes that while this type of data may show an association between cannabis and suicidal thoughts, it doesn’t confirm that it is at the root of the cause. 

“This type of data is correlational versus causational,” she adds.

“It’s just an association and doesn’t mean that cannabis has caused this issue or has improved this issue either, it’s two completely different things.”