Cannabis Use Disorder Linked to Higher Heart Attack Risk

Adults with cannabis use disorder may be at a 60% higher risk of their first heart attack, stroke, or other major cardiovascular event, a study finds.

An estimated 6.3 million Americans aged 12 and older had cannabis use disorder (CUD), or cannabis addiction, in the past 12 months, according to 2021 data.

A new study published in the journal Addiction suggests that having cannabis use disorder may significantly increase the risk of cardiovascular disease events, such as heart attack, stroke, cardiac dysrhythmias, and peripheral vascular disease.

The study included 59,528 individuals, half of whom had CUD and half did not, matched by gender, year of birth, and time of presentation to the health system.

During the seven-year follow-up, 2.4% (721) of those with cannabis use disorder experienced a first-time cardiovascular disease event, compared with 1.5% (458) in the unexposed group.

Those with CUD but without co-occurring medical illness, no prescriptions, and fewer than five visits to health services in the last six months had about 1.4 times higher risk of a first-time cardiovascular event than others within the cannabis-use-disorder group.

Researchers say these people may have considered themselves healthy and, therefore, may not have acted on or even noticed the warning signs of a major cardiovascular event, such as heart attack or stroke.

The study also found that the risk of adverse CUD events increased with the severity of cannabis use disorder.

"Our study doesn't provide enough information to say that cannabis use disorder causes adverse cardiovascular disease events, but we can go so far as to say that Canadians with cannabis use disorder appear to have a much higher risk of cardiovascular disease than people without the disorder," Anees Bahji, lead author of the study, said in a statement.

The study, however, has limitations. Because the severity of cannabis use disorder was measured by the number of times a person had been diagnosed with the condition, misclassification may have occurred.

Additionally, data suggests that CUD is under diagnosed compared to alcohol and multiple substances abuse, meaning that some people with cannabis use disorder may have been misclassified as unexposed.

As a result, the association between CUD and first-time cardiovascular events may have been underestimated. This suggests that the public health implications of cannabis use disorder could be more pronounced.

What is cannabis use disorder?

A person with cannabis use disorder is unable to stop using cannabis even though it's causing health and social problems in their lives. Those who start using cannabis during adolescence or youth, or those who use cannabis more frequently, are at higher risk of developing CUD.

The signs of cannabis use disorder may include:

• Using more cannabis than intended.
• Trying but failing to quit using cannabis.
• Spending a lot of time using cannabis.
• Craving cannabis.
• Continuing to use cannabis despite it causing problems at home, school, or work, or social or relationship problems.
• Using cannabis in high-risk situations, such as while driving a car.
• Continuing to use cannabis despite physical or psychological problems.
• Needing to use more cannabis to get the same high.
• Experiencing withdrawal symptoms when stopping cannabis use.

Long-term cannabis use is associated with a wide range of health issues, such as:

• Breathing problems, including daily cough and phlegm, more frequent lung illness, and a higher risk of lung infections.
• Increased heart rate, which elevates the risk of heart attack.
• When cannabis is used during pregnancy or while breastfeeding, the drug could increase the risk of a preterm birth or affect the baby's developing brain.
• Intense nausea and vomiting, such as those associated with Cannabinoid Hyperemesis Syndrome.

The study authors say that if the causal link between CUD and first-time cardiovascular events is confirmed, treating cannabis use disorder may benefit cardiovascular health.