Going ‘California sober’ could be bad for one’s heart
- That pot is a healthy alternative to alcohol is turning out to be just another marketing myth. A study shows cannabis users are at heightened cardiovascular risk.
Evidence is mounting that a daily toke can be bad for your heart. A large new study in the Journal of the American Heart Association found that the more often one partakes in cannabis, the higher one’s risk of heart disease, heart attack or stroke. Daily users had a 25% higher chance of having a heart attack and 42% higher odds of a stroke than non-users. It’s the latest in a string of studies showing a link between marijuana and heart health. These findings rely on surveys that ask people to recall habits and health conditions, rather than following participants in real time. Memories are fallible and people can also massage the truth. Self-reported use of cannabis in the new study was below what other surveys found. But even so, the trend is clear enough to put cardiovascular risk on the radars of pot users. That’s especially important now that recreational cannabis use is on the rise and is being framed as a ‘healthy’ alternative to drinking. The ‘California sober’ lifestyle, of eschewing alcohol for pot, is catching on.
Cannabis firms are leaning into the aura of health. During Dry January, a public health initiative against alcohol, I was flooded with pitches from cannabis companies hoping to fill the void. One firm said its THC-infused drinks were “healthier and more mindful" than alcohol. Healthier? Maybe — the answer depends on how often and how much of either substance you use and in what format. But healthy? We just don’t have as much good data on marijuana as we do on alcohol—but absence of evidence shouldn’t be confused with proof that pot is harmless.
Conceptually, the idea that weed could increase the risk of cardiovascular events for some shouldn’t be a surprise. Delta-9 THC “very reliably and dose dependently" increases heart rate and cardiovascular stress, says Ryan Vandrey of the Cannabis Science Laboratory at Johns Hopkins University. Meanwhile, some users can experience a significant drop in blood pressure when suddenly sitting up or standing.
This latest study analysed data from the 400,000-plus Americans interviewed each year for the Centers for Disease Control and Prevention’s Behavioral Risk Factor Surveillance Survey. Given that many marijuana users in earlier studies also smoked cigarettes, which have long been associated with heart disease, the data was open to interpretation. People wondered, “Is cannabis an innocent bystander, or does it contribute to coronary heart disease?" says Robert L. Page, a professor at the University of Colorado School of Medicine’s Skaggs School of Pharmacy and Pharmaceutical Sciences. These results drop the façade. An increased risk of heart disease, heart attacks and stroke persisted for the survey participants who had never smoked tobacco or used e-cigarettes. “That is a big answer," says Page, some of whose patients think smoking pot is healthier: “a complete misconception." That’s particularly true for people who already have underlying risk factors or heart disease.
The study left open a number of key questions. For example, the main method of cannabis ingestion among survey participants was smoking. So the research can’t tell us whether popular alternatives like gummies or THC-infused drinks pose an equal risk to heart health. Small studies by Vandrey’s lab have shown that smoking and edibles produce similar changes in heart rate, and other small trials suggest that edibles are also risky. Another missing piece: Does the potency of pot matter? Most of the studies on cannabis and heart health were done on what Page describes as “first-generation cannabis," meaning strains that were cultivated in the wild. But modern dispensaries aren’t selling your grandparents’ weed. THC content today is typically much higher. Does that also mean it’s riskier?
What would help the most at this point is to run a large study that followed subjects over time to understand the connections between cannabis consumption and heart health. That same study could also winnow out any other health effects—good or bad —of recreational use.
The US, especially, needs that type of data. At present, recreational marijuana is legal in 24 states, decriminalized in another seven and could soon be expanded to other parts of the country. That has bred an industry offering an ever-evolving array of products (with an ever-evolving array of cannabinoids at varying doses, consumed in various ways) that have very little toxicology or pharmacology data behind them. “It’s all brand new, and we really do not have a good sense of what the long-term health effects of what those products will be," Vandrey says.
But the data we do have on marijuana suggests that recreational pot users should not assume their habit is benign—much less that it’s healthy. ©bloomberg
