Using marijuana regularly may raise the risk for heart failure, stroke or heart attack even after accounting for other cardiovascular risk factors such as Type 2 diabetes, high blood pressure and obesity, according to two preliminary studies to be presented at the American Heart Association’s Scientific Sessions 2023. The meeting, to be held Nov. 11-13, in Philadelphia, is a premier global exchange of the latest scientific advancements, research and evidence-based clinical practice updates in cardiovascular science.
The use of marijuana, medically known as cannabis, is gaining popularity across the U.S. as more states legalize it for recreational and medical use. However, how marijuana affects the heart and brain health is still not completely known. Two new studies, by separate research groups, shed light on the association for regular marijuana use with risk for heart failure, heart attack and stroke.
More than 150,000 adults in the U.S. participated in the All of Us Research Program, a National Institutes of Health-sponsored program. Researchers focused on the relationship between lifestyle, biology and environment in diverse populations and analyzed the association between daily marijuana use and heart failure.
“Prior research shows links between marijuana use and cardiovascular disease like coronary artery disease, heart failure and atrial fibrillation, which is known to cause heart failure,” said lead study author Yakubu Bene-Alhasan, M.D., M.P.H., a resident physician at Medstar Health in Baltimore. “Marijuana use isn’t without its health concerns, and our study provides more data linking its use to cardiovascular conditions.”
Bene-Alhasan and colleagues followed 156,999 individuals who were free from heart failure at the time they enrolled in the research program. Study participants completed a survey about the frequency of their marijuana use and were followed for nearly 4 years (45 months). The analysis was adjusted to account for individual demographic and economic factors, alcohol use, smoking and other cardiovascular risk factors linked with heart failure, such as Type 2 diabetes, high blood pressure, high cholesterol and obesity.
The analysis found:
- During the study period, 2,958 people (almost 2%) developed heart failure.
- People who reported daily marijuana use had a 34% increased risk of developing heart failure, compared to those who reported never using marijuana. This risk was the same regardless of age, sex at birth or smoking history.
- In a secondary analysis, when coronary artery disease was added to the investigation, the risk of heart failure dropped from 34% to 27%, suggesting that coronary artery disease is a pathway through which daily marijuana use may lead to heart failure.
“Our results should encourage more researchers to study the use of marijuana to better understand its health implications, especially on cardiovascular risk,” Bene-Alhasan said. “We want to provide the population with high-quality information on marijuana use and to help inform policy decisions at the state level, to educate patients and to guide health care professionals.”
- The definition of marijuana use was using marijuana when not prescribed for a health condition, or, if prescribed for medical purposes, using it beyond that purpose.
- The median participant age was 54 years; 60.9% of participants were female at birth; 70.7% self-identified as white adults; 21.8% were Black or African American adults; 4.2% were Asian adults; 2.2% were identified as more than one race/ethnicity; and 1.1% were from other races/ethnicities.
- The study enrollment began in June 2016. Participants were followed from when they enrolled until June 2022, a maximum of approximately 4 years (45 months).
A limitation of the study is that it relied on data that did not specify whether the marijuana was inhaled or eaten. According to researchers, how marijuana is ingested may influence cardiovascular outcomes.