The American Heart Association is calling on the United States to deschedule cannabis so more research can be done on how it affects heart health.
Cannabis use has exploded in the past 25 years while research largely remained tied up in red tape, warns the association in an article published in its own journal, Circulation, this week. Its authors reviewed dozens of scientific studies on how cannabis affects heart health and found that the outcomes are likely not good — but the AHA says it doesn’t have hard evidence to prove it.
“Overall, evidence is still inconclusive for cannabis use and adverse cardiovascular outcomes, resulting in an urgent need for carefully designed, prospective short- and long-term studies,” reads the report.
Additional research could be critical to saving lives in the U.S. Heart health is a massive problem in the country with heart disease being the leading cause of death according to the Centers for Disease Control and Prevention. That’s one in every four fatalities, or 647,000 people every year. Heart disease impacts the economy too, costing the country US$219 billion from 2014–2015.
Despite being a Schedule 1 drug, the National Institute on Drug Abuse reports weed as being the second most commonly used psychotropic drug in the country, following alcohol. In January a Gallup poll found 12 per cent of Americans reported smoking cannabis — that’s 39.4 million people.
So it makes sense why the country’s largest organization dedicated to fighting heart disease might want to know more about weed.
Descheduling it will allow for a more nuanced approach to legalization and regulation, the report’s authors argue. It would also remove legal barriers to funding research and clinical trials on potential risks and benefits.
So what does the research say about hearts and weed?
It seems to depend on the cannabinoids, says the AHA. Tetrahydrocannabinol (THC) makes your heart beat faster, changes your blood pressure when lying on your back and increases the heart muscle’s demand for oxygen. Cannabidiol (CBD) by contrast slows down your heart rate, lowers blood pressure and reduces inflammation.
One thing is clear, the AHA says: Smoking weed puts tar in your lungs and that’s bad.
However, the study acknowledges that cannabis does have beneficial therapeutic uses. Solid scientific evidence shows weed can be used to treat pain and anorexia. It can also treat the nausea and vomiting brought on by chemo therapy, multiple sclerosis spasticity and some forms of epilepsy. The AHA notes emerging research suggesting cannabis can help reduce opioid use and treat glaucoma as well.
Interestingly, the authors referenced a study looking at 161,000 patients with heart failure and found people who used weed were less likely to die from acute heart failure, spent less time in the hospital and had a lower hospital bill at the end of their stay. But the AHA said the study was retrospective, observational and lacked peer review.
The AHA review didn’t shy away from listing negative health effects of weed: It pointed out how cannabis legalization leads to a rise in weed-related hospital visits, and how the 2019 vaping-related illness outbreak was linked to unregulated THC vapes — an illness that hospitalized 2,807 people and killed 68, according to the most recent CDC numbers from February 2020.
But when it comes to if or how weed affects heart health, the AHA says present evidence is insufficient.
As well as calling for the descheduling of cannabis, the AHA says it wants to see comprehensive FDA regulation on CBD products and for the country to integrate equality considerations for weed policy development development to ensure racial and ethnic disparities are not further exacerbated.
Read a full list of the AHA’s calls to action on page e.18 of the report.
Given the recent explosion and lightning pace of cannabis research, it should be noted that creating reliable scientific consensus takes time.
In November 2019 the AHA published a study suggesting cannabis use can increase a person’s risk of stroke. Seven months later the University of Mississippi published a study that found there was no correlation. Less restrictions on research in the U.S. would help clear the smoke.
Top image of a hotel in New York lighting up a heart to show its support for healthcare workers during the Covid-19 pandemic. Photo by Anthony Quintano via Wikimedia Commons