AHA: Evidence suggests no CV benefit, possible harm from cannabis use
There is no documented benefit of cannabis use for CVD prevention or treatment, according to a scientific statement from the American Heart Association.
In addition, there is preliminary evidence that cannabis use may have a negative impact on the heart and blood vessels, according to the statement.
“Attitudes towards recreational and medicinal use of cannabis have changed rapidly, and many states have legalized it for medical and/or recreational use. Health care professionals need a greater understanding of the health implications of cannabis, which has the potential to interfere with prescribed medications and/or trigger cardiovascular conditions or events, such as heart attacks and strokes,” Robert L. Page II, PharmD, MSPH, FAHA, chair of the writing group for the statement and professor in the department of clinical pharmacy and the department of physical medicine/rehabilitation at the University of Colorado Skaggs School of Pharmacy and Pharmaceutical Sciences in Aurora, Colorado, said in a press release.
No documented CV benefits
While there are known benefits of cannabis use for pain management, nausea and vomiting, multiple sclerosis spasticity and epilepsy, among other areas, “there are no well-documented cardiovascular benefits of cannabis,” Page and colleagues wrote.
However, they wrote, observational studies have noted several negative CV effects from cannabis use, including:
- Tetrahydrocannabinol, the chemical in cannabis that causes a “high,” stimulates the sympathetic nervous system; increases heart rate, myocardial oxygen demand, supine BP and platelet activation; and is linked with endothelial dysfunction and oxidative stress.
- Carbon monoxide intoxication, which can occur with excessive cannabis smoking, is associated with risk for cardiomyopathy, angina, acute MI, arrhythmias, cardiac failure, pulmonary edema, cardiogenic shock and sudden death, but there is little evidence as to whether cannabis use directly causes these conditions.
- In states where cannabis use is legal, there has been an increase in hospitalizations and ED visits for acute MI and cannabis-associated adverse effects.
- A retrospective study found an association between regular cannabis use and elevated risk for cerebrovascular accident.
- In another study, 6% of patients aged 50 years or younger with acute MI used cannabis regularly, and cannabis use was associated with worse CV and all-cause mortality.
In contrast, there is no evidence of CV harm from cannabidiol products, according to the statement.
Caution, more research needed
Anyone seeking to use cannabis should consult with a health care professional, Page said in the release.
“If people choose to use cannabis for its medicinal or recreational effects, the oral and topical forms, for which doses can be measured, may reduce some of the potential harms,” he said. “It is also vitally important that people only use legal cannabis products because there are no controls on the quality or the contents of cannabis products sold on the street.”
He also said more and better-designed studies are needed.
“We urgently need carefully designed, prospective short- and long-term studies regarding cannabis use and cardiovascular safety as it becomes increasingly available and more widely used,” Page said in the release. “The public needs fact-based, valid scientific information about cannabis’ effect on the heart and blood vessels. Research funding at federal and state levels must be increased to match the expansion of cannabis use — to clarify the potential therapeutic properties and to help us better understand the cardiovascular and public health implications of frequent cannabis use.”