The American Heart Association (AHA) has produced a new statement about medical marijuana and recreational cannabis. The gist? Using weed may not be good for your heart.
The full statement is available here but the main takeaway points are as follows:
- Observational studies have found no cardiovascular benefits associated with cannabis use.
- Cannabis use may be linked to an increased risk of heart attacks, atrial fibrillation and heart failure.
- Additional studies need to be conducted to better understand the research findings.
Pertinent to the third point is that cannabis is classified as a Schedule I drug by the U.S. Drug Enforcement Agency (DEA), which has severely limited scientists from studying it.
“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,” said Robert L. Page II, Pharm.D., M.S.P.H., FAHA, in a press release. Page is 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.
“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,” Page added.
A recent study cited in the statement suggests that cannabis use has been noted in 6 percent of heart attack patients under 50 years of age. Another study found that cannabis users ages 18 to 44 were significantly higher risk of having a stroke compared to nonusers.
The available data tends to be short-term, observational and retrospective, which can identify trends but not prove cause and effect. However, the AHA statement says for people diagnosed with heart disease, cannabis should be used with extreme caution because it increases the heart’s need for oxygen at the same time as it decreases available oxygen supply, which could cause angina (chest pain).
Smoked and inhaled cannabis, the statement adds, can have deleterious effects, independent of the content of THC, which makes people high. Smoking and inhaling cannabis has been shown to increase the concentration of blood carboxyhemoglobin (carbon monoxide, a poisonous gas) five-fold, and tar (partly burnt combustible matter) three-fold—similar to the effects of inhaling a tobacco cigarette.
Sources: AHA Journals, heart.org, CNN