Dear Doctors: Cannabis is legal where I live. I’m not a heavy user, but I do enjoy it now and then. I just heard about a study that ties using cannabis to heart disease. There’s not a lot of information about how using cannabis affects your health, and I would like to know more about that study.
Dear Reader: We should begin with the fact that, despite changes to regulations in a growing number of states, cannabis remains illegal at the federal level. Commonly known as marijuana, it is classified as a Schedule I substance under the Controlled Substances Act. Possession or distribution of cannabis is a federal offense. At the state level, a complex patchwork of laws allows cannabis use for medical or recreational use. Limits vary on the types and amounts of cannabis products allowed, as well as the legal age for their use.
It’s true we don’t know much about the health effects of cannabis. Federal drug laws have limited research opportunities for a long time. Now, the loosening of restrictions in the United States and other nations is providing more data from national surveys, epidemiological studies and clinical research. We are in a steep learning curve about the drug’s possible health effects.
Last spring, the journal Heart published a study from researchers in France. The focus of the study was how regular cannabis use may affect the cardiovascular system. The researchers looked at health data collected from 24 studies. The data covered 200 million adults from ages 19 to 59. They separated the data into two groups, regular users of cannabis and nonusers. Analysis found that cannabis users had a 29% higher risk of a heart attack and a 20% higher risk of a stroke.
As with all observational studies, this research can only point to a possible link between cannabis use and cardiovascular events. It doesn’t prove or explain the connection. But it does echo previous research noting the burden cannabis use places on the heart. This includes heart arrhythmia, high blood pressure and increased heart rate. This applies to smoking the drug and edibles as well. A study from researchers at the University of California, San Francisco, published last spring, found that regular users of edibles had reduced vascular function, by more than 55%, compared to nonusers.
Cardiovascular disease continues to be the leading cause of death in the U.S. With cannabis use growing (around 15% of adults by current estimates), these newest findings are concerning. Older adults and those with existing heart conditions are at particular risk of adverse outcomes. All of this makes it important to consider the potential risks before using cannabis. At the very least, discuss cannabis use when you see your health care provider.
(Send your questions to [email protected], or write: Ask the Doctors, c/o UCLA Health Sciences Media Relations, 10960 Wilshire Blvd., Suite 1955, Los Angeles, CA, 90024. Owing to the volume of mail, personal replies cannot be provided.)
