Study: Marijuana Smoking Not Associated With Greater Mortality Risk Among Heart Attack Survivors

Thursday, 31 January 2013

Study: Marijuana Smoking Not Associated With Greater Mortality Risk Among Heart Attack SurvivorsBoston, MA: The use of cannabis among patients with established coronary disease is not associated with increased mortality risk, according to trial data published online in the American Heart Journal.

Investigators at the Harvard Medical School, Beth Israel Deaconess Medical Center, conducted a prospective study assessing the survival rates of 3,886 heart attack survivors over an 18-year period.

Authors reported that 519 subjects died during this period, including 22 of the 109 reporting marijuana use in the year before their heart attack. However, investigators concluded, "There was no statistically significant association between marijuana use and mortality."

Previous research has speculated that cannabis consumption may increase subjects' risk of heart attack or stroke because cannabinoids may temporarily increase blood pressure, particularly in more naïve users, and because the chronic use of the substance has been linked to the increased production of a specific protein associated with cardiovascular risks.

The study's findings contradicted those of a previous report by the same research team, which was based on the results of a smaller cohort.

"In this prospective multicenter cohort study of MI (myocardial infarction) survivors followed prospectively for up to 18 years, there was no conclusive evidence of an association between smoking marijuana and mortality," authors concluded. They caution, however: Larger studies with repeated measures of marijuana use are needed to definitively establish whether there are adverse cardiovascular consequences of smoking marijuana among patients with coronary heart disease. Given the prior evidence, ... it seems prudent to caution patients with coronary heart disease and those at high risk for cardiovascular disease to abstain from smoking marijuana."

For more information, please contact Paul Armentano, NORML Deputy Director, at: paul@norml.org. Full text of the study, "Marijuana use and long-term mortality among survivors of acute myocardial infarction," is available from the American Heart Journal.