With marijuana use on the rise in the United States, two new studies strengthen existing evidence that regular intake negatively impacts heart and brain health, according to the American Heart Association. Photo by Peggy and Marco Lachmann-Anke/Pixabay
Nov. 6 (UPI) -- Two new preliminary studies on recreational marijuana and health strengthen existing evidence that regular use negatively impacts heart and brain health, according to the American Heart Association.
The first report, drawing on data from a major study involving more than 150,000 people from all walks of American society looking at the relationship between lifestyle, biology and environment, found daily use of marijuana raised the risk of developing heart failure by about one-third compared with non-users.
A research team from Medstar Health, a not-for-profit health provider in the Baltimore-Washington metro area, found that among 156,999 healthy people it followed, those who used marijuana had a 34% higher risk of developing heart failure during the 45 months of the study, compared to those who reported never using marijuana.
This risk was the same regardless of age, sex, or smoking history with the findings of the study -- part of the National Institutes of Health's All of Us research program -- suggesting that coronary artery disease was the pathway through which daily marijuana use may lead to heart failure.
A total of 2,958 people, just under 2% of participants, developed heart failure during the study period.
The analysis took into account demographic and economic factors, alcohol use, smoking and other cardiovascular risk factors associated with heart failure, including Type 2 diabetes, high blood pressure, high cholesterol and obesity.
"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, a resident physician at Medstar Health in Baltimore.
"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 authors, however, noted in their findings that data the study utilized did not differentiate whether the marijuana intake was via smoking or by mouth, which can make a difference to its impact on the cardiovascular system.
The study defined marijuana use as non-prescription intake, or if for medical use, not using as prescribed or beyond its intended use.
The average age of participants was 54 with 60.9% of participants women. Almost 72% were white against just under 22% who were Black or African Americans and 4.2% were Asian adults. The remaining 3.3% were from other races and ethnicities, or identified as having more than one race or ethnicity.
A separate study of 28,535 older non-tobacco users hospitalized with any combination of Type 2 diabetes, high blood pressure and high cholesterol found marijuana users had a 20% higher risk of a major acute heart or brain event compared with non-users, and 13.9% were struck by a serious heart event or stroke.
The study which drew on the data of patients aged 65 years or older from the 2019 National Inpatient Sample, also found 7.6% of cannabis users suffered a heart attack compared with 6% of non-users and were 50% more likely to be transferred to other facilities.
"Since 2015, cannabis use in the U.S. has almost doubled, and it is increasing in older adults, therefore, understanding the potential increased cardiovascular risk from cannabis use is important," said lead study author Dr. Avilash Mondal, a resident physician at Nazareth Hospital in Philadelphia.
"We must be mindful about major heart and stroke events in older adults with cannabis use disorder. At this point, we need more studies to understand the long-term effects of cannabis use."
Mondal urged physicians to always ask about cannabis or marijuana use when taking a patient's medical history.
"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."
The study adds yet more weight to the growing body of evidence that high blood pressure, defined by this study as 130/80 mm Hg or above, and high cholesterol are predictors of major adverse heart and brain events in individuals who use marijuana.
The authors cautioned that study limitations include possible coding errors in patients' health records regarding marijuana due to the sheer size of the database used and variations between hospitals in the electronic code for cannabis use disorder which could skew their analysis findings.
The two studies, which are preliminary and have yet to be peer-reviewed, are to be presented at the AHA's 2023 Scientific Sessions in Philadelphia from Saturday through next Monday.