"A paper from a colleague of mine, Dr. Murray Mittleman, published in Circulation in 2001, showed that the heart attack rate increased by 4.8-fold during the hour after smoking marijuana," Lavie said. "Therefore, since the risk factors of heart attack and stroke are similar, it makes sense that both could be increased by pot smoking."
With drug studies, some also wonder if the researchers have an ethical bias, but the author said his concern lies with the drug's high popularity level.
"I don't have any moral position, but it's important people know there are potential risks," Barber said. "There's a perception out there that cannabis is a natural substance and what's the problem about? For medicinal reasons, it's different. For cancer, it stimulates the appetite. But if you use it for recreation, you need to know the risks," Barber said.
The U.S. National Institute on Drug Abuse has more about the health effects of marijuana.
SOURCES: Alan Barber, M.D., Ph.D., professor, clinical neurology, University of Auckland, New Zealand; Daniel Labovitz, M.D., director, Stern Stroke Center at Montefiore Medical Center, New York City; Carl Lavie, M.D., professor, medicine and medical director, cardiac rehabilitation and prevention, John Ochsner Heart and Vascular Institute, New Orleans; Feb. 6, 2013, presentation, American Stroke Association annual meeting, Honolulu
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