Americans are getting high in record numbers. And as the number of people using marijuana increases, evidence is growing to suggest it may be linked to certain heart problems. What is not clear is whether these risks are due to smoking it or if it is THC (delta-9-tetrahydrocannabinol, the main psychoactive ingredient in the cannabis plant) that could be harmful to health.
About one in five people over the age of 12 (about 61.9 million people in the United States) have used marijuana in the last year, up from 52.5 million the year before, according to data from the National Survey on Drug Use and Drug Abuse. Health published on November 13. As more states legalize its use, cannabis is becoming the most popular drug.
The idea that marijuana is not harmful is so widespread that, according to a recent Pew Research Center survey, nine out of 10 people in the United States they believe marijuana should be legal for both medicinal and recreational use.
But recent studies have found links between marijuana use and cardiovascular problems, such as abnormal heart rhythms and even heart attacks. Despite this, some of the results are contradictory: some studies have detected a risk of heart failure, and others have not. And while no definitive conclusions can be drawn about heart risk, researchers believe these signals should not be ignored.
Earlier this month, the American Heart Association presented preliminary results of two studies showing that marijuana use is linked to an increased risk of heart attack and heart failure.
The results of the first study, which analyzed people with an average age of 54, found a 34% increase in the risk of heart failure in people who used marijuana daily compared to those who had never done so.
In the second study, researchers looked at patients who were admitted to hospitals for any reason, and found that people who used marijuana and had a disease such as type 2 diabetes had a significantly higher risk of having a heart attack, stroke, heart rate or an abnormal heart rhythm, compared to patients who did not use cannabis.
“I’m very concerned,” said Robert Page, a clinical pharmacist specializing in heart disease at the University of Colorado Skaggs School of Pharmacy. “It appears that cannabis may be a risk factor in the development of cardiovascular diseases,” he added.
According to Dr. Peter Grinspoon, one of the leading cannabis researchers in the United States, while it is important to note that the two studies do not directly prove that marijuana causes heart problems, it is an issue that needs to be examined as soon as possible.
“We absolutely need to investigate this much further,” said Grinspoon, a primary care physician at Massachusetts General Hospital and an instructor at Harvard Medical School, “it’s critical that we answer the questions.”
Is marijuana harmful to the heart?
Early results from a large study conducted in Denmark last year revealed that using medical marijuana for chronic pain was associated with a 64% increased risk of abnormal heart rhythms, such as atrial fibrillation, which can raise the risk of stroke or death. The research did not show an increased risk of heart failure.
THC, the cannabis ingredient that gets marijuana users high, could be affecting the heart through activation of the sympathetic nervous system, which is our body’s “fight or flight” response. This can trigger an increase in heart rate and blood pressure, putting more pressure on the heart.
“Anything that can raise the heart rate can cause heart attacks and potentially heart failure,” Grinspoon said.
Page, lead author of a comprehensive report on cannabis published by the American Heart Association in 2020, wrote that cannabis may have some therapeutic benefits, but not for the heart. “At this time, there are no cardiovascular benefits whatsoever with cannabis in any form,” he stressed.
Is smoking it the harmful thing or is it the weed itself?
That’s where science enters murky territory. Because it can take years to conduct scientific research and evaluate its results, cannabis studies are often conducted with older forms of marijuana that are much lower in potency than today’s. The potency of cannabis—measured by the amount of THC found in the product—has been increasing for almost half a century: an increase of 0.29% annually from 1970 to 2017.
Although most studies have looked at people who smoke marijuana, more data is needed, Grinspoon said. Her main guess is that it is the smoke, which has the same type of carcinogens and tar found in tobacco cigarettes, and not the marijuana itself, that may be affecting the heart.
“Certainly (marijuana smoke) is not as bad as tobacco smoke, which kills 480,000 people a year,” Grinspoon said, “but cannabis smoke contains cyclic aromatic hydrocarbons, and these are things that can’t possibly be argue that they are good for the heart.”
Cyclic aromatic hydrocarbons are chemicals that result from the combustion of tobacco, coal, oil, gas, wood and garbage that are harmful to DNA.
Although vaping can mitigate some of the toxic chemicals in smoke, it is also not without risk, says Dr. Robert Kloner, a cardiologist and scientific director of the Huntington Medical Research Institutes in Pasadena, California.
“Vaping could be safer than smokingbecause the tars and carbon monoxide associated with tobacco are not inhaled,” he says.
Ultimately, what matters most is the dose consumed.
“If you inhale it once a week at a party, that’s not going to pose much danger to your heart,” Grinspoon said. “But if you’re puffing on a vaporizer, say, 30 times a day, of course it’s going to be bad for your heart,” he added.
Are marijuana edibles safe?
Little is known about cannabis-containing edibles such as gummies, chocolates, candies, brownies or drinks, Page said. Although the number of children intoxicated by inadvertently consuming marijuana edibles has skyrocketed, there is “very limited data” on the effect they have on the body, Page said.
Marijuana Edibles May Be Less Dangerous because they do not include smoke inhalation. “When you eat an edible, you’re not inhaling any of the products of combustion, which are especially bad for the heart and can cause hardening of the arteries,” Grinspoon said.
Again, it’s all about the dosage. “If you eat half a gummy, or 2.5 milligrams, and fall asleep, you are very unlikely to have coronary heart disease,” Grinspoon explained.
(A study reveals how marijuana use affects pregnancy during pregnancy)
Who is at risk?
People with coronary heart disease, hardening of the arteries, or a family history of heart disease should be cautious.
“If you had a heart attack six weeks ago, I would not start using cannabis,” Grinspoon stressed, “I would be very, very cautious, unless there were incredibly compelling indications (about its benefits),” he added, referring to patients who They use marijuana for medicinal purposes.
If the heart of someone with arterial disease begins to beat faster and demand more oxygen because THC triggers the “fight or flight” response, that could be a problem. “It’s kind of a double whammy,” she explained, “that can cause a heart attack.”
Even Young who may not know if they have high cholesterol or blood pressure – conditions that put them at higher risk for heart disease. they have to be careful.
“They believe they are invincible and (then) consume a cannabis product and may have a cardiac episode,” he stressed.