Smoking marijuana may double the risk of a rare condition that temporarily weakens the heart, researchers, including those of Indian origin, have warned.
Active marijuana use may double the risk of stress cardiomyopathy, an uncommon heart muscle malfunction that can mimic heart attack symptoms, researchers said.
Stress cardiomyopathy is a sudden, usually temporary, weakening of the heart muscle that reduces the heart’s ability to pump, leading to chest pain, shortness of breath, dizziness and sometimes fainting, they said. Active marijuana use was identified either by information provided by the patient in their medical history, or by a marker in the patient’s urine.
“The effects of marijuana, especially on the cardiovascular system, are not well known yet. With its increasing availability and legalisation in some states, people need to know that marijuana may be harmful to the heart and blood vessels in some people,” said Amitoj Singh from St Luke’s University Health Network in the US.
Data from the US Nationwide Inpatient Sample identified 33,343 people who were hospitalised with stress cardiomyopathy between 2003-2011 in the US.
Of those, 210 (less than 1%) were also identified as marijuana users. Compared with non-users, researchers found that marijuana users were more likely to be younger, male with fewer cardiovascular risk factors, including less high blood pressure, diabetes and high cholesterol.
However, despite being younger and with fewer cardiovascular risk factors than non-users, during stress cardiomyopathy the marijuana users were significantly more likely to go into cardiac arrest (2.4% vs 0.8%) and to require an implanted defibrillator to detect and correct dangerously abnormal heart rhythms (2.4% vs 0.6%).
“This development of stress cardiomyopathy in younger patients who used marijuana suggests a possible link that needs to be further investigated,” said Sahil Agrawal from St Luke’s.
Marijuana users were more likely than non-users to have a history of depression – 32.9% vs 14.5%, psychosis (11.9% vs 3.8%), anxiety disorder (28.4% vs 16.2%), alcoholism (13.3% vs 2.8%), tobacco use (73.3% vs 28.6%) and multiple substance abuse (11.4% vs 0.3%).
Since some of these can increase the risk of stress cardiomyopathy, the researchers adjusted for known risk factors to investigate the association between marijuana use and stress cardiomyopathy. “If you are using marijuana and develop symptoms such as chest pain and shortness of breath, you should be evaluated by a healthcare provider to make sure you aren’t having stress cardiomyopathy or another heart problem,” Singh said.