Preliminary Study Links Cannabis Use to Higher Stroke Odds in 442,906 Adults

Start with what this is — and what it is not. This is preliminary research: a poster abstract (Mo3041) scheduled for presentation at the American Heart Association's Scientific Sessions 2026, November 6–9 in Chicago. It has not been peer reviewed, and under the AHA's own rules, meeting abstracts are considered preliminary until the work is published as a full manuscript in a peer-reviewed journal. What it reports is an association in survey data — not proof that cannabis use causes cardiovascular disease.

What the Researchers Found

The analysis pooled 2020–2024 data from the Behavioral Risk Factor Surveillance System (BRFSS), the CDC's telephone survey, covering 442,906 U.S. adults (average age 49; about half women) in the states that included the optional cannabis module — between 16 and 24 states a year, not the whole country.

Compared with people who reported no cannabis use in the past month:

• Low-frequency users (1–5 days in the past month) had 23 percent higher odds of reporting a history of cardiovascular disease — and 40 percent higher odds of reporting a stroke.
• Heavy users (16–30 days in the past month) had 21 percent higher odds of reporting cardiovascular disease — and 25 percent higher odds of stroke.
• There was no statistically significant association between how often people used cannabis and heart attack.

The link held regardless of form — smoked, vaped or eaten — according to the release. The AHA release did not report results for the moderate-frequency group (6–15 days a month) and did not provide confidence intervals, so the numbers above cannot be checked for precision from the release alone.

The pattern surprised the researchers, because risk did not climb steadily with heavier use.

"We were surprised to find that the link between cannabis use and cardiovascular disease was not straightforward," 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. "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."

How It Was Done — and the Limits

Participants reported how many days they had used cannabis in the previous month and whether a health professional had ever told them they had cardiovascular disease — a heart attack, coronary heart disease or a stroke. The odds were calculated after adjusting for demographics, tobacco smoking, alcohol use, obesity, diabetes, chronic kidney disease, physical inactivity, education and income.

The AHA's own list of limitations is substantial. The study captures one point in time, so it cannot show that cannabis use came before the disease — or caused it. Everything rests on self-reported survey answers, subject to memory error. The researchers had no information about the potency of the cannabis used or how much was consumed. People may have cut back or quit after a diagnosis, which can blur the comparison groups, and the no-recent-use group can include former users.

Robert L. Page II, Pharm.D., M.S.P.H. — chair of the writing group for the AHA's 2020 scientific statement on cannabis, who was not part of this study — said the tobacco question hangs over all of it: many patients who use cannabis also smoke tobacco, which "completely clouds the issue" for cardiovascular risk. He also called the work the second observational study to suggest cannabis exposure, apart from tobacco smoking, may be a potential risk factor for cardiovascular disease.

Why It Is Being Released Now

Use keeps climbing. Divya noted that 1 in 6 U.S. adults reported past-month cannabis use in 2024, up from 1 in 10 in 2020 — a 51 percent increase.

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

The new analysis also lands differently from earlier work. A 2024 Journal of the American Heart Association study using 2016–2020 BRFSS data found a graded pattern — more days of use, higher odds, including for heart attack. The new data does not reproduce that staircase: the strongest stroke signal sits in the lightest-use group, and the heart-attack association is absent. That inconsistency is itself a reason the findings need peer review and a full manuscript before they carry weight.

For now, the honest summary is narrow: in a very large telephone survey, people who said they used cannabis were more likely to say a professional had diagnosed them with cardiovascular disease — most clearly stroke. Whether cannabis caused any of it is a question this study, by design, cannot answer.

Sources

1. American Heart Association. "Cannabis Use Linked to an Increased Risk of Cardiovascular Disease, Especially Strokes." News release, November 2, 2026 (embargoed until 4 a.m. CT). — The primary source: preliminary research to be presented as poster abstract Mo3041 at AHA Scientific Sessions 2026, Nov. 6–9, Chicago; 442,906 BRFSS respondents (2020–2024, states with the optional cannabis module); low-frequency use (1–5 days/month) associated with 23% higher odds of cardiovascular disease and 40% higher odds of stroke; heavy use (16–30 days) with 21% and 25%; no statistically significant heart-attack association; adjustments, limitations, and the quotes from Divya and Page; the AHA's notice that meeting abstracts are not peer-reviewed and findings are preliminary until published as a full manuscript. As carried by Medical Xpress, medicalxpress.com/news/2026-10-cannabis-linked-cardiovascular-disease.html, and NewMediaWire.
2. The American Journal of Managed Care (AJMC). "Occasional Cannabis Use Linked to 40% Higher Odds of Stroke." November 2, 2026. — Independent trade-press coverage of the same release confirming the sample (442,906 adults, average age 49, about half women), the use categories, the 23%/21% cardiovascular and 40%/25% stroke odds, the absence of a heart-attack association, and that the AHA release did not report the moderate-frequency group or provide confidence intervals. ajmc.com/view/occasional-cannabis-use-linked-to-40-higher-odds-of-stroke
3. CannabisNews.org. "Even Occasional Cannabis Use Tied to Higher Stroke Odds in Survey of Nearly 443,000 U.S. Adults, Preliminary AHA Study Finds." November 2, 2026. — Corroborating coverage restating the preliminary, not-peer-reviewed status, the BRFSS 2020–2024 pooling, and the contrast with the 2024 Journal of the American Heart Association analysis of 2016–2020 BRFSS data (434,104 respondents), which found daily use associated with higher odds of heart attack and stroke. cannabisnews.org

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