Even occasional marijuana use linked to 40% higher odds of stroke

New preliminary research involving more than 440,000 American adults has uncovered a concerning association between cannabis use and cardiovascular disease, particularly stroke. The findings suggest that even occasional marijuana use may be linked to higher odds of cardiovascular problems, raising new questions about the health effects of a substance that is becoming increasingly common across the United States.

The research, presented at the American Heart Association's Scientific Sessions 2026, found that the association was not limited to people who frequently used cannabis. It also appeared across different methods of consumption (smoked or edible, etc.). Researchers emphasized that cannabis use should be considered when discussing heart health and stroke prevention.

Scientific Sessions 2026 took place November 6 through 9 in Chicago, bringing together cardiovascular researchers and healthcare professionals from around the world to share scientific discoveries, clinical advances, and emerging evidence.

Cannabis refers to the plant itself, while marijuana is a commonly used term for cannabis products containing enough THC to produce psychoactive effects.

Marijuana Use Is Rising Across the United States

"Previous research has indicated that cannabis use is rapidly increasing in the United States, with 1 in 6 adults in 2024 reporting having used it within the last month, up from 1 in 10 in 2020 -- a 51% increase," said study author Aabha Divya, M.B.B.S., M.Ch., an assistant professor in the division of cardiothoracic surgery at the Tulane University School of Medicine in New Orleans.

Earlier research conducted between 2016 and 2020 had already identified associations between cannabis consumption and unfavorable cardiovascular outcomes. Those findings also suggested that using cannabis more frequently during a given month was connected to greater cardiovascular risk.

However, the evidence has not always been consistent. With recreational marijuana becoming legal in more places and cannabis products increasingly available, Divya and colleagues wanted to investigate these possible health effects in a larger population.

"We wanted to expand on this earlier work because cannabis use has become increasingly common in the United States, as recreational legalization and commercial availability of various products with cannabis have also expanded. Previous studies have raised concerns about possible cardiovascular effects; however, the results have not been consistent," Divya said.

The researchers examined information collected through the Behavioral Risk Factor Surveillance System (BRFSS), a large telephone survey of American adults. They combined responses from jurisdictions that collected information about cannabis consumption between 2020 and 2024.

Participants answered questions about their marijuana use and whether a healthcare professional had ever diagnosed them with cardiovascular conditions, including a heart attack, stroke, or coronary heart disease.

Even Occasional Marijuana Use Was Linked to Higher Stroke Odds

One of the most striking findings was that infrequent cannabis use was associated with cardiovascular problems. In fact, the researchers did not find the steady increase in cardiovascular risk with more frequent use that they had expected.

The analysis revealed several important associations:

• Occasional cannabis use: Adults who reported using cannabis on 1 to 5 days per month had 23% higher odds of reporting a history of cardiovascular disease compared with those who reported no use.
• Heavy cannabis use: People who consumed cannabis on 16 to 30 days per month had 21% higher odds of reporting a history of cardiovascular disease.
• Stroke: The strongest association involved stroke. People reporting low-frequency cannabis use had 40% higher odds of reporting a history of stroke, while heavy users had 25% higher odds.
• Heart attacks: Researchers found no statistically significant association between how frequently participants used cannabis and whether they had experienced a heart attack.

These findings were unexpected because the relationship between cannabis use and cardiovascular disease did not consistently become stronger as consumption increased.

"We were surprised to find that the link between cannabis use and cardiovascular disease was not straightforward. We expected that the chances of heart disease would gradually rise as people used cannabis more often, but that wasn't the case. Both low-use and heavy-use groups had higher odds of developing heart disease," Divya said.

Although the study cannot establish that marijuana directly causes strokes or other cardiovascular conditions, the findings suggest that occasional consumption should not automatically be considered free of potential cardiovascular concerns.

"As cannabis use becomes more common, it is increasingly important that people and their healthcare professionals include it in conversations about cardiovascular health, just as they discuss tobacco, alcohol and other commonly used substances," she added.

Experts Urge Greater Attention to Cannabis and Heart Health

Robert L. Page II, Pharm.D., M.S.P.H., FAHA, who led the writing group responsible for the American Heart Association's 2020 cannabis scientific statement, said the findings add to growing concerns about marijuana's possible cardiovascular effects.

One challenge in evaluating those effects is that many cannabis users also smoke tobacco. Because tobacco is already an established cardiovascular risk factor, separating its effects from those of cannabis can be difficult.

Page, who was not involved in the research, explained why the new findings deserve attention.

"Unfortunately, many patients who use cannabis may also smoke tobacco, which completely clouds the issue when addressing atherosclerotic cardiovascular disease risk. In patients who use both, cannabis has always been considered an innocent bystander; however, this is not the case. This is the second observational study to suggest that cannabis exposure (without tobacco smoking) may be a potential risk factor for developing cardiovascular disease. Overall, cannabis is beginning to emerge as a major contributor to premature heart disease in young and older adults, which can lead to serious cardiovascular events. To this end, clinicians should be addressing cannabis use with their patients as they would tobacco use when considering the risk of cardiovascular disease."

Page is a professor in the department of clinical pharmacy and the department of physical medicine/rehabilitation at the University of Colorado Skaggs School of Pharmacy and Pharmaceutical Sciences in Aurora, Colorado.

How Researchers Studied Nearly Half a Million Americans

The analysis included 442,906 adults living in the United States (average age of 49 years; approximately half women). Their responses came from telephone surveys conducted through the BRFSS.

Researchers used survey information collected from 2020 through 2024, focusing on states that had included an optional marijuana questionnaire. Between 16 and 24 states participated in this portion of the survey each year, meaning the analysis did not represent every state.

Participants reported how many days they had consumed cannabis during the preceding month. The questions covered multiple ways of using marijuana (smoking, vaping or ingesting gummies or other cannabis-containing foods).

The researchers divided participants into four categories based on their reported use:

• No recent use: No cannabis consumption during the previous 30 days.
• Low-frequency use: Cannabis consumption on 1 to 5 days during the previous month.
• Moderate-frequency use: Consumption on 6 to 15 days.
• Heavy use: Consumption on 16 to 30 days.

Participants also indicated whether they had ever received a diagnosis of heart attack, heart disease, heart-related chest pain, or stroke.

To better distinguish the association with cannabis from other potential explanations, the researchers accounted for numerous established cardiovascular risk factors. These included demographic characteristics, tobacco smoking, alcohol consumption, obesity, diabetes, chronic kidney disease, physical inactivity, education, and income.

Why the Findings Do Not Prove Marijuana Causes Strokes

Despite the large number of participants, the study has several limitations that affect how its findings should be interpreted.

First, the analysis examined associations between reported cannabis use and previously diagnosed cardiovascular conditions at a single point in time. This means researchers could not determine whether marijuana use preceded the cardiovascular problems or whether it directly contributed to them.

The information also depended on participants accurately recalling and reporting their cannabis consumption and medical histories (making them subject to potential errors in memory). Such reports may not always reflect actual patterns of use or diagnoses.

Another limitation was the lack of information about the strength of the cannabis products participants consumed or the quantities they used. Without those details, the researchers could not evaluate whether THC potency or the amount consumed influenced the observed associations.

The researchers also acknowledged that some participants may have reduced or discontinued cannabis consumption after being diagnosed with cardiovascular disease. As a result, the group reporting no cannabis use in the previous month may have included former users.

These uncertainties make it difficult to draw firm conclusions about how consumption frequency affects cardiovascular health. Nevertheless, the findings add to growing evidence that cannabis use deserves closer examination as a possible factor in heart disease and stroke.

As marijuana becomes more widely available and its use continues to increase, researchers and healthcare professionals are emphasizing the importance of discussing cannabis alongside other substances that may affect cardiovascular health.