For those who often used marijuana and also smoked cigarettes or e-cigarettes, the risk was even greater.
According to a new study, young people who often use marijuana are more than twice as likely to have a stroke as those who do not use it at all.
The findings, which will be presented next week at the annual meeting of the American Heart Association (AHA) Scientific Sessions in Philadelphia, contribute to a growing number of studies linking the use of marijuana to an increased risk of cardiovascular issues. The new study, which will also be published in a new issue of the journal Stroke, is one of the first studies to focus specifically on the risk of stroke among young cannabis users (younger than 45 years).
Analyze the results of a national survey
The researchers analyzed the results of a national study, called the Behavioral Risk Factor Surveillance System, which had published data on the use of marijuana and the incidence of stroke.
The authors compared the frequency of marijuana use with the incidence of stroke in people 18 to 44 years old. Among the 43.860 participants, 13,6% had used marijauna in the past 30 days. (The data does not indicate how participants used marijuana, although a majority of survey respondents said they had smoked it). Marijuana users also often reported heavy drinking and taking tobacco cigarettes.
The authors found that frequent users of marijuana, or people who used marijuana for more than 10 days a month, but who did not use tobacco products, were nearly 2,5 times more likely to have a stroke than people who did not use marijuana, according to a statement.
Even greater risk for smokers of cigarettes or e-cigarettes
For those who often used marijuana and also smoked cigarettes or e-cigarettes, the risk was even greater. These individuals were nearly three times more likely to have a stroke compared to those who did not use marijuana or cigarettes.
But these findings only show a connection and cannot prove that the use of marijuana causes strokes. The authors noted that other substances, such as alcohol, can of course also influence the risk of stroke as seen in the study, although in their analysis the scientists tried to focus as much as possible on analysis with additional substance use.
The exact cause of a stroke remains unclear
Furthermore, it is important to report that even if there is a cause-and-effect relationship between the use of marijuana and stroke, the researchers do not know exactly how the drug can lead to a stroke. Marijuana use is linked to an increased number of blood clots, which in turn could increase the risk of stroke, according to an earlier Live Science report.
Cannabis can also cause "reversible cerebral vasoconstriction," or a temporary narrowing of the blood vessels in the brain associated with stroke, said lead author Dr. Tarang Parekh, a health policy researcher at George Mason University in Virginia.
"In the current discussion of marijuana legalization in the United States, we believe this study was a critical step towards" understanding stroke in young marijuana users, "said Dr. Parekh. "While cannabis is not [as] harmful or addictive as other substances, we cannot ignore the potential health risks."
A separate study, which will also be presented at the AHA meeting next week, found a link between the use of marijuana and an increased risk of cardiac arrhythmias (or arrhythmias) in young adults. The authors discovered that young people, or between the ages of 15 and 34, who have a cannabis use disorder, had an 47% to 52% increased risk of being hospitalized due to an arrhythmia (heart rhythm disorder).
This latter study has not yet been published in a peer-reviewed journal.