Cannabis users were 35 percent more likely to be diagnosed with atrial fibrillation within a decade compared to non-users.
Researchers said the heart condition is the most common type of treated heart arrhythmia that can lead to stroke, heart failure, and other heart-related complications. But it can often go undiagnosed because many people do not experience symptoms.
The latest study, which included data from 23 million patients also looked at the risk of heart arrhythmias among users of other drugs.
Cocaine users were 61 percent more likely to develop AF than people who did not use the drug.
People who used opiates, which can include heroin and prescription drugs, were at 74 percent increased risk of developing severe arrhythmia.
The report, authored by researchers at the University of California San Francisco, was published in the European Heart Journal.
They wrote: ‘Despite exhibiting a weaker association with incident AF than the other substances, cannabis use still exhibited an association of similar or greater magnitude to risk factors like dyslipidemia, diabetes mellitus, and chronic kidney disease.’
‘Furthermore, those with cannabis use exhibited similar relative risk of incident AF as those with traditional tobacco use,’ they said.
In cases of atrial fibrillation, the upper chambers of the heart, or the atria, beat chaotically and out of sync with the lower chambers, or ventricles, of the heart.
Researchers analyzed data from every hospital admission and every visit to outpatient surgical facilities and emergency departments in California from 2005 through 2015, collecting information from a total of 23 million people.
Just a fraction of patients included in the study used drugs: 132,834 used cannabis, 98,271 used methamphetamine, 48,700 used cocaine, and 10,032 used opiates.
Marijuana is the third-most commonly used drug in the US behind alcohol and tobacco, and its prevalence is growing as more states embrace its therapeutic and medicinal properties.