Young and middle-aged adults who use marijuana may have an increased risk of suffering heart complications, a new study has found.

French scientists analysed serious heart-related complications following marijuana use that had been reported in France between 2006 and 2010.

The majority of patients analysed were male, with an average age of 34.

The scientists identified 35 cases of cardiovascular and vascular conditions, 22 of which were directly related to the heart. These included 20 heart attacks.

The study found that the percentage of reported heart-related complications more than tripled between 2006 and 2010. Furthermore among the 35 patients studied, one in four died.

They also noted that people with pre-existing heart issues appeared to be more at risk from the harmful effects of the drug.

"There is now compelling evidence on the growing risk of marijuana-associated adverse cardiovascular effects, especially in young people. It is therefore important that doctors, including cardiologists, be aware of this, and consider marijuana use as one of the potential causes in patients with cardiovascular disorders," the scientists said.

They noted that in previous research, they had identified ‘several remarkable cases of cardiovascular complications as the reasons for hospital admission of young marijuana users'.

"This unexpected finding deserved to be further analysed, especially given that the medicinal use of marijuana has become more prevalent and some governments are legalising its use," they commented.

They pointed out that both marijuana use and any resulting complications are probably under-reported.

"The general public thinks marijuana is harmless, but information revealing the potential health dangers of marijuana use needs to be disseminated to the public, policymakers and healthcare providers," they said.

The scientists called for more research into how marijuana might trigger heart-related events.

Details of these findings are published in the Journal of the American Heart Association.

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