Could smoking marijuana weaken the heart?


More and more states in the US are voting to legalise marijuana used for recreational purposes.
Many people who use it point to perceived health benefits. However, a new study suggests that the opposite might be the case; that marijuana may be harmful to the heart.
New research, presented at the American Heart Association in New Orleans, suggested that use of the drug could weaken heart muscles, particular in young men.
In a study set up specifically to look at the links between using marijuana and heart health, researchers from St Luke’s University Hospital Network examined people with stress cardiomyopathy.
This is a sudden condition where temporary weakening of the heart muscles prevent them from pumping blood around the body. Those who suffer can believe they are having a heart attack because it causes chest pain, breathlessness and dizziness.
It can often happen during times of severe stress or grief, which is why it is often said that it is possible to die from a broken heart.
However, Dr Amitoj Singh said as well as stress and grief, there are also links between stress cardiomyopathy and drug use.
He said: “There have been many reports of heart attacks, strokes and two cases of stress cardiomyopathy that have been linked to marijuana.”
Dr Singh said that medics were becoming increasingly concerned about the risk to patients’ hearts as a result of marijuana becoming more readily available for recreational use.
The researchers took information from Nationwide Inpatient Sample data from 2003 to 2011, looking at 33,343 patients who had been admitted to hospital with stress cardiomyopathy.
Two groups were examined, including the patients who did not use marijuana, and the one per cent of people who did.
Dr Singh said “Someone who uses marijuana is almost two times more likely to develop stress cardiomyopathy.”
However, because people who used marijuana were also more likely to smoke tobacco and other illicit substances, the research could not conclude how much of an influence the marijuana alone had.
Dr Ann Bolger, who is a professor of clinical medicine at the University of California, said: “It’s hard to know exactly that you can account for all of these other contributors” when determining causation of the condition.”
Dr Singh said it was now vital that more research was carried out to fully determine the impact of marijuana use on heart health.