Rats Exposed To Cannabis Smoke Once A Day Experienced Harmful Effects On The Heart, FDA & AHA Funded Study

A common belief that marijuana and e-cigarettes are healthier alternatives to traditional tobacco cigarettes has just been disproved by new research from the University of California San Francisco.

According to the study, published Tuesday in the journal Heart Rhythm, there’s evidence that e-cigarettes and cannabis have damaging effects on the heart that are similar to the negative effect of tobacco cigarettes. Vapes, joints and cigarettes can cause abnormal heart rhythms, writes Kron. 

“We found that cigarettes, e-cigarettes, and marijuana greatly interfere with the electrical activity, structure, and neural regulation of the heart,” lead author Dr. Huiliang Qiu, a postdoctoral scholar in the UCSF Division of Cardiology, stated. “Often, any single change can lead to arrhythmia disease. Unfortunately, these adverse effects on the heart are quite comprehensive.”

The research was funded by the California Tobacco-Related Disease Research Program, the American Heart Association, the FDA Center for Tobacco Products, the National Institutes of Heart and other partners. 

Experts say for a heart to work well, it must pump blood efficiently and with the correct rhythm. The heart itself has an electrical control system connected to our nervous system. If any part of the heart does not act on those electrical control signals as it should, it could cause other parts of the heart to behave asynchronously. So, instead of working as one (efficient pump), parts of the heart could function against each other, causing potentially life-threatening arrhythmias.

Another UCSF study published in the European Heart Journal also confirmed that substances such as cocaine, opiates, methamphetamine and even marijuana are linked to the most common type of heart arrhythmia - atrial fibrillation often called AF or AFib.

The new UCSF study focused on ascertaining whether consumption of new tobacco products of cannabis can cause the development of proarrhythmic substrate and eventually lead to arrhythmias.

Study Methodology 

“Rats were exposed to smoke from tobacco; marijuana or cannabinoid-depleted marijuana; to aerosol from electronic cigarettes or heated tobacco products; or to clean air once per day for 8 weeks,” scientists wrote. “The rats exposed to tobacco or marijuana products exhibited progressively increased systolic blood pressure, decreased cardiac systolic function with chamber dilation, and reduced overall heart rate variability, relative to the clean air negative control group.”

“It's notable that all of these tobacco and marijuana products had similar effects. And what's really striking is that this was caused by a single realistic smoking/vaping session per day,” said senior author Matthew Springer, Ph.D., a UCSF professor of cardiology.

Springer highlighted that neither e-cigarettes, IQOS, nor cannabis joints “should be assumed to be a harmless replacement for smoking.” 

The main study limitation is that it was conducted on rats and not humans. 

Photo: Benzinga Edit; Sources: Giorgio Trovato on Unsplash and Pixabay