Two new studies presented at the American Heart Association’s Scientific Sessions 2023 suggest that regular marijuana use may be associated with an increased risk of heart failure and heart attacks, especially among older adults.
The research, which has yet to be published in a peer-reviewed journal, indicates that daily cannabis use is linked to a 34% higher risk of developing heart failure compared to non-users.
For older adults with cardiovascular risk factors, marijuana use was associated with a 20% increased likelihood of experiencing a major adverse cardiac event while hospitalized.
Experts say the findings highlight the need for further investigation into the cardiovascular effects of cannabis, as well as improved patient education and communication between healthcare providers and their older patients regarding marijuana use.
Daily Cannabis Use Linked to 34% Higher Risk of Heart Failure
In the first study, researchers analyzed data on 156,999 participants from the National Health and Nutrition Examination Survey (NHANES) who were free of heart failure at the start of the study.
Participants self-reported their frequency of cannabis use, defined as “using marijuana when not prescribed for a health condition, or, if prescribed for medical purposes, using it beyond that purpose.”
Over a follow-up period of 45 months (nearly 4 years), 2,958 participants (1.9%) developed heart failure. After adjusting for demographics and other risk factors, the researchers found that individuals who used cannabis daily had a 34% higher risk of developing heart failure compared to those who never used cannabis.
When further adjusting for coronary artery disease, the risk was slightly attenuated but remained significantly elevated at 27%. This suggests coronary artery disease may be one mechanism by which frequent marijuana use raises heart failure risk, according to researchers.
“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 Dr. Yakubu Bene-Alhasan, a resident physician at Medstar Health in Baltimore, in a press statement.
“Marijuana use isn’t without its health concerns, and our study provides more data linking its use to cardiovascular conditions,” Bene-Alhasan added.
“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 observational study was not able to determine causality and did not have information on methods of cannabis use, which researchers noted could impact cardiovascular outcomes.
Marijuana Use in Older Adults Linked to 20% Higher Risk of Major Cardiac Events
A second study focused specifically on older adults aged 65 and over with cardiovascular risk factors.
Using data from the 2019 National Inpatient Sample, the largest publicly available database representing hospitalizations in the U.S., researchers identified 28,535 cannabis users and 28,535 non-users matched on age, sex and race. Tobacco users were excluded from the analysis.
The results showed that among older adult cannabis users hospitalized with cardiovascular risk factors, 13.8% experienced a major adverse cardiovascular or cerebrovascular event, compared to 11.6% of non-users.
After adjusting for confounders, marijuana use was associated with a 20% higher risk of experiencing a heart attack, heart failure, stroke or transient ischemic attack while hospitalized.
“We must be mindful about major heart and stroke events in older adults with cannabis use disorder,” said lead study author Dr. Avilash Mondal, a resident physician at Nazareth Hospital in Philadelphia, in a statement.
“The main public message is to be more aware of the increased risks and open the lines of communication so that cannabis use is acknowledged and considered,” Mondal added.
More Research Needed, But Findings Highlight Potential Risks
The researchers of both studies emphasized that more research is required to fully understand the cardiovascular effects of cannabis, especially among older adults who may be more vulnerable to adverse events.
Future studies should evaluate the impact of different methods of use, dosages and cannabis strains.
However, the current findings highlight the need for greater public awareness of the potential risks associated with marijuana use.
Healthcare professionals are encouraged to specifically ask older patients about cannabis use as part of routine medical history taking.
“Our results should encourage more researchers to study the use of marijuana to better understand its health implications, especially on cardiovascular risk,” said Dr. Bene-Alhasan.
With a growing number of states legalizing marijuana for recreational and/or medical use, experts say it is crucial that the public is informed about both the purported benefits and potential health hazards of cannabis products.
More research is key to developing proper guidelines and recommendations for safe use.
For now, these preliminary studies indicate that frequent cannabis use may increase the likelihood of heart failure and cardiac events in older adults.
Moderation is advised, and patients with cardiovascular risk factors should have an open discussion with their doctor about marijuana use as part of their overall heart health management.