(Montreal) The consumption of four substances, including cannabis, could increase the risk of suffering from atrial fibrillation, a very common and potentially serious form of cardiac arrhythmia, warns a new American study.
Posted at 1:42 p.m.
The other three substances are cocaine, opioids and methamphetamines. The case of cannabis, however, is a bit special, since it is a product that can be obtained very easily and legally.
“It’s interesting to see that cannabis is added to the list of risk factors for atrial fibrillation,” commented Dr. Alexandre Raymond-Paquin, a specialist in electrophysiology and this cardiac disorder at the Institut de Montreal Cardiology.
“We already had smaller studies, a little less robust, which suggested such an association, so I’m not completely surprised, but I’m happy to see that we can finally establish a somewhat stronger association between cannabis use and atrial fibrillation. »
Researchers at the University of California, San Francisco analyzed data from 23.5 million Californian adults who needed hospital care between 2005 and 2015. None had atrial fibrillation (a disorganization of the electrical activity in the atria) at the start of the study.
About 133,000 of them were cannabis users, 98,000 methamphetamine users, 49,000 cocaine users and 10,000 opiate users.
After ten years, nearly one million patients, or 4.2% of the total, suffered from atrial fibrillation. The strongest association was found with methamphetamines and the weakest with cannabis. The risk of suffering from this form of arrhythmia was still 35% higher among cannabis users.
Harmless substance… or not
In the popular imagination, cannabis is often seen as a more mundane and harmless substance than cocaine, opioids and methamphetamines. However, underlines Dr. Raymond-Paquin, cannabis is accompanied by “potentially deleterious effects on the cardiovascular level” of which the population must be informed.
“Just because it’s legal doesn’t mean it’s good for your health,” he recalled, notably drawing a comparison with tobacco. Just because it comes from a plant doesn’t mean it’s healthy. »
Beyond an increased risk of atrial fibrillation mentioned in this study, other research has linked cannabis to a greater risk of stroke, heart attack and heart failure, added the specialist, but other studies will be necessary to deepen the whole.
The mechanisms by which each substance might increase the risk of atrial fibrillation remain unclear. We do know, however, says Dr. Raymond-Paquin, that cannabis acts on several receptors, particularly at the level of the nervous system, the cardiovascular system and the heart muscle, which would be the cause of a certain “disorder”.
“But I have to say it’s an evolving science, and then probably we’ll have more answers in the near future,” he said.
Atrial fibrillation is the most common form of arrhythmia. It affects 2% of the general population, 4% of those aged 65 and over and 12% of those aged 80 and over. The problem can lead to stroke if not taken care of properly.
While some risk factors such as age, sex and genetics are not modifiable, others ― such as high blood pressure, obesity, physical inactivity and alcohol consumption ― are, and Cannabis consumption could be added to this list, concluded Dr. Raymond-Paquin.
“It’s by trying to control all these risk factors that you can put the odds in your favor,” he said.
The conclusions of this study have been published in the pages of the European Heart Journal.