That being said, some past research has suggested marijuana use is linked to an increased chance of a heart attack in people who have existing cardiovascular issues. A new study published in the Canadian Medical Association Journal shows regular cannabis use could also increase the chance of a heart attack in young adults who do not have cardiovascular issues.
Canadian researchers looked at health data from more than 30,000 young adults — people between the ages of 18 and 44 — collected for the American Behavioral Risk Factor Surveillance System telephone survey between 2017 and 2018. They found 4,610 identified as cannabis users, and young adults who use cannabis have a 1.3% chance of having a heart attack, which is almost twice as high as the 0.8% chance among people who don’t use cannabis.
The increase should be understood in relative terms, Dr. Karim Ladha — co-author of the study and an anesthesiologist at St. Michael’s Hospital and the University of Toronto — tells The News Station.
“It’s important to understand that the absolute risk to individuals who are young and otherwise healthy and using cannabis is still quite low,” Ladha says. “It’s not as if anyone who smokes a joint is going to drop dead from a heart attack the next day.”
The researchers tried to test the association between marijuana use and an increased risk of heart attack in as many ways as they could to see if it would go away, but it remained no matter how they analyzed the data. They’re not sure why there is this correlation between cardiovascular issues and cannabis use, but they have some theories.
“A lot of people think that the relationship between cannabis and cardiovascular health is simply due to smoking, and that probably has some part of it, but there are also other potential mechanisms,” Ladha says. “There is some data to suggest that THC, in and of itself, can affect the cardiovascular system, such as with increases in heart rate or causing irregular heart rates.”
When your heart rate increases, the heart needs more oxygen to function. If the body isn’t able to supply an adequate amount of oxygen to the heart, that can cause a heart attack. But more research will need to be done before we can understand what’s really going on here, Ladha says.
Other experts are still waiting for further studies. Mitch Earleywine, a professor of psychology at the State University of New York at Albany, tells The News Station he believes this data could be correct, but he has some concerns.
“This distinction between relative risk and absolute risk can confuse the general public. Essentially, cannabis use might increase risk for this problem from a little less than 1% to a little more than 1%,” Earleywine says. “I do hope these data might inspire everyone to improve their diets, exercise more regularly, and take a few moments each day to decrease their stress. But I fear these results will be misinterpreted as some sort of rationale to return to prohibition.”
The findings won’t stop Ladha from prescribing medical marijuana to his chronic-pain patients, he says. He just thinks it’s important to know all of the facts, so physicians and their patients are well informed when making medical decisions. The more information we have, the better.