Researchers caution that cannabis use is not without risk.
People who used marijuana daily were found to be about one-third more likely to develop coronary artery disease (CAD) compared with people who have never used the drug, according to a study that will be presented at the American College of Cardiology’s Annual Scientific Session Together With the World Congress of Cardiology.
As cannabis becomes legal in an increasing number of U.S. states, this study is among the largest and most comprehensive to date to examine the potential long-term cardiovascular implications of using the drug. CAD is the most common form of heart disease and occurs when the arteries that supply blood to the heart become narrowed due to a buildup of cholesterol. CAD commonly causes chest pain, shortness of breath and fatigue, and can lead to a heart attack.
Previous studies have reported somewhat mixed findings on the relationship between cannabis and heart disease, with some suggesting that smoking marijuana can raise the risk of heart attack, stroke, and other cardiac events, especially in younger people.
“We found that cannabis use is linked to CAD, and there seems to be a dose-response relationship in that more frequent cannabis use is associated with a higher risk of CAD,” said Ishan Paranjpe, MD, a resident physician at Stanford University and the study’s lead author. “In terms of the public health message, it shows that there are probably certain harms of cannabis use that weren’t recognized before, and people should take that into account.”
Using data from the All of Us Research Program of the National Institutes of Health, which includes detailed information about the health and habits of 175,000 people, researchers first analyzed the relationship between cannabis use frequency (assessed using surveys at the time of enrollment in the study) and rates of CAD (assessed based on medical records spanning several years). They then used Mendelian randomization, a genetics-based approach to identify a causal relationship between cannabis use disorder and CAD risk using data from an independent genetics consortium. Cannabis use disorder is a recognized psychiatric disorder involving frequent marijuana use and dependency.
After adjusting for age, sex, and major cardiovascular risk factors, the results indicated that daily cannabis users were 34% more likely to have CAD than those who have never used marijuana. In contrast, monthly cannabis use was not associated with a significant increase in the risk of CAD. The Mendelian randomization analysis suggested that this was due to a causal relationship, finding that people with cannabis use disorder were more likely to develop CAD. Additionally, in the genetic analysis, this causal relationship was independent of the potential confounding effects of tobacco and alcohol use.
Based on these findings, researchers said it is important for people to be aware that cannabis use is not without risk and make sure to inform their doctor if they use cannabis so that clinicians can take appropriate steps to monitor their heart health.
Previous studies have suggested that tetrahydrocannabinol (THC), the molecule responsible for the psychoactive effects of cannabis, acts on receptors that are found in the central nervous system and in the heart and blood vessels. This interaction between THC and blood vessels may provide a pathway for cannabis to promote inflammation and the buildup of plaque, ultimately leading to CAD. The same effects would not necessarily be expected with the use of cannabidiol (CBD), another active ingredient in cannabis and hemp that is commonly extracted for products that do not contain THC.
By helping to better understand the molecular pathways involved in marijuana use and heart disease, the findings could open new opportunities for interventions to prevent or treat heart disease.
“From a scientific standpoint, these findings are exciting because they suggest there might be new drug targets and mechanisms we can explore to take control of this pathway going forward,” Paranjpe said.
The datasets used in this study did not differentiate between various forms of cannabis use—for example, whether the drug was smoked or consumed in edibles or other forms. Since THC enters the body through a different pathway and gets to the brain more quickly when cannabis is smoked rather than eaten, researchers said it could be helpful to examine the health implications of these different forms of cannabis consumption in future studies.
Although the use and possession of cannabis remain illegal under federal law, over half of U.S. states have legalized or decriminalized recreational use of marijuana and three-quarters allow it to be used for medical purposes. A study conducted in 2019 estimated that about 18% of U.S. adults used marijuana in that year.
Paranjpe will present the study, “Association of Cannabis Use Disorder With Risk of Coronary Artery Disease: A Mendelian Randomization Study,” on Sunday, March 5, 2023, at 9:30 a.m. CT / 15:30 UTC in Poster Hall, Hall F.
That is such. B. S. Doctor told me 15 years ago, after I had a heart attack, if I quit smoking cigarettes I could smoke all the weed I wanted. Smoking lowers my blood pressure. Why don’t you guys talk about real killers like sugar, and alcohol.
Long time frequent user. At 55 I almost had a heart attack, had 99% blockage on the widow maker artery. Had a stent put in. Currently on meds for cholesterol and high BP. I eat well and exercise daily, have been since I was 20. Was this caused by 30 years of smoking weed? Very possible.
Did any of these super smart researchers ever stop to think that it’s probably not the smoking of marijuana, but what the people are eating AFTER they smoke that is the cause?…
Agreed with Dragonfly-Girl. Someone should study how many daily weed users succumb to what is known as “the munchies.” So unless we have some weight and fitness stats along with the weed usage, this is a bogus study. Almost feels like a study that was paid for by an anti-weed platform…
I wonder what Willie Nelson would say about this.
Stop telling lies.i have been a frequent smoker of marijuana and been smoking since the 70s(68 now)and still enjoy a smoke,also helps with the pains of getting older.
Or maybe its because daily users are actually chronically ill and already have a poor lifestyle. Or the munchies? Because who sits after smoking and thinks “a salad would be fantastic right now”. It’s literally our diet that’s killing us.
This is so b.s. weed is prescibed to people who have illnesses and chronic pain or cancer or many other health problems caused by the horrible chemicals that are in our food and water that we are encouraged to eat and drink by Drs. Give me a break
What a joke! Cannabis isnt worse than cigarettes! Tobacco and alcohol is legal and has killed many more people. Lets be honest..Some United states we have here…
I AGREE W/ YALL. THIS ARTICLE IS BS. I WAS BORN W/ HEART PROBLEMS , HAD (3) PACEMAKERS SINCE MY EARLY 20’S. MY DR. TOLD ME IF I COULD FIND A DR. TO PRESCRIBE ME POT. HE’D HELP ME. I ALSO HAVE ANXIETY , PTSD , REOCCURRING DEPRESSION, SEVERE SCOLOSIS , & DEAF IN 1 EAR & LOST MOST HEARING IN THE OTHER. ALSO HAVE SLEEPING PROBLEMS & BAD NERVES. POT HELPS ME. BECAUSE I’M ALLERGIC TO ALMOST EVERY PAIN MEDICINE KNOWN TO MAN. SO , PLZ EXPLAIN TO ME HOW SMOKING POT CAUSES HEART PROBLEMS ? REDO YALLS RESEARCH !
Beware the munchies sweet and salty and fries with HFC ketsup pizza soda ice cream shakes BBQ potato chips milk chocolate chip cookies ordering late night food and snacks and drinks unchilled white rice curede meat and prces#ed
It is a flawed, coralation, not causation study. They assume this will create inflammation when they have no scientific clue as to why. So there must be a connection. Junk science. I they are using what ever they can right now to explain all the heart attacks happening lately and we all know what is really behind it.
They have a “sugary and fatty processed foods use disorder”.
There is no such thing as a “cannabis use disorder”; that is just “made up” by c*ns*rv*t*v*s pretending to be scientists, just like they make up all kinds of “disorders” they don’t like, such as “homosexuality disorder”.
Intelligent folks have patiently discredited all that bunk.