Cannabis can 'kill people who suffer from an irregular heartbeat'
Cannabis can kill people who suffer from an irregular heartbeat, warns new research.
Doctors say anyone with a heart rhythm disorder - known as an arrhythmia - should not use cannabis.
A study of more than 2.4 million hospitalised cannabis users found that those with an arrhythmia were 4.5 times more likely to die while in hospital than those without.
Study author Dr Sittinun Thangjui, of Bassett Healthcare Network in the United States, said: "People should be aware of this devastating outcome and be careful when using cannabis if they have a concomitant heart problem."
Cannabis is the most commonly used psychoactive substance worldwide. But little is known about the safety of the drug for people with cardiac arrhythmias.
Researchers examined the burden of arrhythmias in drug users admitted to hospital for the new study. They also compared length of hospital stay and deaths in hospital between those with and without an arrhythmia.
The study was conducted using the National Inpatient Sample database, which covers 97 per cent of the US population.
It included 2,457,544 adult cannabis users admitted to hospital from 2016 to 2018. Of those, 187,825 patients (7.6 per cent) had an arrhythmia.
Atrial fibrillation was the most common, followed by abnormally slow heart rate and abnormally fast heart rate.
Patients in the arrhythmia group were older, with an average age of 50.5 years compared to 38.3 for those without an arrhythmia. Those with arrhythmias also had more co-existing health conditions.
The researchers compared deaths between the two groups after adjusting for factors including sex, age, race, income, diabetes, heart failure, chronic kidney disease, obesity, and hospital location.
Cannabis users with an arrhythmia had a 4.5 times higher odds of dying in hospital compared to those who did not. Patients with an arrhythmia also had a longer length of hospital stay (5.7 days) compared to those without (5.1 days).
Dr. Thangjui said: "Our study highlights that heart rhythm disorders may be a warning sign for an increased risk of death in people who use cannabis."
He added: "More studies are needed to confirm our results. In the meantime, it seems sensible to screen these patients for arrhythmias if they present to hospital so that those with a heart rhythm problem can be closely monitored."
The findings were presented at EHRA 2021, an online scientific congress of the European Society of Cardiology.