Couple smoking marijuana together

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WASHINGTON — Whether you smoke marijuana or consume edibles, regular use could be spending you to an early grave, a new study warns. Researchers working with the American College of Cardiology say those who smoke marijuana or eat weed-laced edibles daily are significantly more likely to develop coronary artery disease (CAD). This is one of the largest studies on the long-term toll the drug inflicts on the heart, revealing that the more you smoke, the higher the risk for heart disease.

CAD is the most common form of heart disease. Cholesterol narrows the arteries supplying blood to the organ, causing chest pain, shortness of breath, and fatigue. It can cause heart attacks.

The significant link remains regardless of whether users smoked tobacco, drank alcohol, had major cardiovascular risk factors — regardless of their age and sex. Whether users consumed cannabis by smoking, eating edibles, or through other methods, also made no difference.

1 in 5 American adults use marijuana

Marijuana consistently ranks as one of the most popular drugs in many countries. Meanwhile, decriminalization in many U.S. states means around 18 percent of adults across the country use the drug each year. Cannabis use disorder is a recognized psychiatric disorder involving how often people use the drug, and how dependent they are. Researchers are calling for the public to realize that smoking weed is not risk free.

The American College of Cardiology researchers add that people should let their doctors know if they use the drug, so clinicians can start monitoring heart health.

“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,” says lead study author Ishan Paranjpe, MD, a resident physician at Stanford University, in a media release. “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.”

“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 says.

marijuana grow house
(Credit: CRYSTALWEED cannabis on Unsplash)

Heart disease over 30 percent more likely among marijuana users

The team compared how often 175,000 participants smoked weed with the rates of CAD diagnosis in the group versus the wider U.S. population. They applied a genetic-based method of identifying a causal link between using cannabis and developing heart disease. Those who smoked or consumed the drug daily were 34 percent more likely to develop CAD.

Previous studies show the psychoactive molecule that gets users “high” — THC (tetrahydrocannabinol) — acts on receptors in the central nervous system in the heart and blood vessels. THC’s interaction with blood vessels could inflame the tubes and allow plaque to build up, leading to CAD.

Scientists do not expect the same effects using CBD (cannabidiol). CBD is another active ingredient in hemp and weed, often extracted for products without THC. Understanding marijuana’s risk to the heart could help clinicians develop new interventions.

Next, researchers would like to follow up the study, presented at the American College of Cardiology’s Annual Scientific Session Together With the World Congress of Cardiology, by investigating the health-implications of taking cannabis in different forms.

South West News Service writer Pol Allingham contributed to this report.

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  1. Michael says:

    Where are the footnotes for the study, so people can read it? The study appears to use very generalized language to describe its results.

  2. Pete Shea says:

    Did the study also take diet and exercise into full account. For examples, are users less likely to eat healthy diets and exercise than non-users?