Marijuana Law Reform Advocate Responds to Latest Report on Weed and Heart Attacks Data

The Deputy Director at the National Organization for the Reform of Marijuana Laws offers an assessment of the latest headlines about weed and heart attacks.


Image via Getty/Hector Vivas


A leading marijuana law reform organization has shared a detailed response to a headlines-spurring study that was making the usual rounds on Tuesday morning.

The study in question appeared in the Canadian Medical Association Journal this week before being featured in a CNN piece, notably under a headline informing readers that “young adult cannabis consumers [are] nearly twice as likely to suffer from a heart attack.”

Those behind the study analyzed data from more than 33,000 “young adults” between the ages of 18 and 44, ultimately determining that of the 17 percent of adults who said they had recently used weed, 1.3 percent had a history of myocardial infarction (i.e. heart attack). Meanwhile, per the ensuing report, 0.8 percent of respondents who said they had not recently used weed reported a history of myocardial infarction.

Asked by Complex for his take on the coverage surrounding this study, Paul Armentano—the Deputy Director of the National Organization for the Reform of Marijuana Laws (NORML) nonprofit—noted that data of this type has been “frustratingly inconsistent.”

Armentano pointed Complex to several examples of this inconsistency, including a literature review published in the American Journal of Medicine earlier this year in which it was concluded that marijuana itself “does not appear to be independently associated with excessive cardiovascular risk factors.”

Pointed out in the same previously published review highlighted by Armentano is the potential for “other unhealthy behaviors” to be associated with marijuana, though marijuana alone wasn’t linked with cardiovascular concerns. In other words, let this serve as merely the latest reminder that correlation does not necessarily equal causation.

This also serves as the basis for the wave of criticism brought against the framing of the latest study, which drew some impassioned questioning on Twitter. Special mention, understandably, was given to the fact that the aforementioned article itself notes that “the study did not research how cannabis affects heart health.”

Or it may not be, because this study makes no attempt to show causation between cannabis use and heart attacks. Good tweet though.

— Nick Wing (@nickpwing) September 7, 2021

Refer madness called they want their propaganda back.

— i am Grootsseau (@WhiskeyBuffalo) September 7, 2021

Below, see Armentano’s full statement to Complex:

“Data evaluating the potential link between cannabis exposure and cardiovascular risks are frustratingly inconsistent. 

For instance, longitudinal data conducted by the University of California finds no increased risk of adverse cardiovascular events in younger and middle-aged subjects with a history of cannabis use of several decades. 

More recently, a population-based study published in 2021 reported that a history of cannabis use was associated with a decreased risk of adverse cardiovascular events, once researchers controlled for potential confounders. They determined, “After controlling for several confounding variables, we found that there was a decrease in the prevalence of cardiovascular events with marijuana use (Odds Ratio: 0.74).”

By contrast, a 2020 review of nearly 134,000 US adults reported, ‘Frequent marijuana smoking is associated with significantly higher odds of stroke and myocardial infarction or coronary artery disease, with a possible role in premature cardiovascular disease.’

Finally, the results of a 2021 literature review of 67 studies published in The American Journal of Medicine concluded, ‘[M]arijuana itself does not appear to be independently associated with excessive cardiovascular risk factors.’ Authors did caution, however, that ‘it can be associated with other unhealthy behaviors such as alcohol use and tobacco smoking that can be detrimental’ to cardiovascular health.”

And for more on the current fight to continue pushing for marijuana law reform nationwide, click here.

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