Study shows heart problems increase over time due to cannabis usage
Emilie Jouanjus, PharmD, PhD, of the Centre Hospitalier Universitaire de Toulouse and colleagues reported and examined 35 recent remarkable cardiovascular complications following cannabis use.
For the study researchers used data from the French Addictovigilance Network which relies on the spontaneous reporting of serious abuse and dependence cases related to psychoactive drug use. Health professionals have the legal obligation to report to their regional addictovigilance center all serious cases.
The French Addictovigilance Network was requested to search cases of cannabis‐related cardiovascular complications during the past 5 years (2006 to 2010).
Among cannabis‐related reports (35) most cardiovascular complications had occurred in men (85.7%) with an average age of 34 years. Cardiovascular history and risk factors could be found for 46% of cases (16 out of 35) with nine men having a personal history of cardiovascular disease and seven had a familial history.
There were 22 cardiac complications; 20 acute coronary syndromes, 10 peripheral complications (lower limb or juvenile arteriopathies and Buerger‐like diseases), and 3 cerebral complications (acute cerebral angiopathy, transient cortical blindness, and spasm of cerebral artery). In 9 cases, the event led to patient death.
In their conclusion the researchers write “Increased reporting of cardiovascular complications related to cannabis and their extreme seriousness (with a death rate of 25.6%) indicate cannabis as a possible risk factor for cardiovascular disease in young adults, in line with previous findings. Given that cannabis is perceived to be harmless by the general public and that legalization of its use is debated, data concerning its danger must be widely disseminated. Practitioners should be aware that cannabis may be a potential triggering factor for cardiovascular complications in young people.”
Dr. John P. Erwin, III, MD, FACC, of Baylor Scott and White Health in Temple, Texas, commented to MedPage Today, "there seems to be a more than mere coincidental association between marijuana use in young people and cardiovascular events, although this study certainly cannot fully implicate causation."
"Marijuana use, in the form of smoking, is extremely difficult to study given lack of strong control groups with extreme variation in THC concentrations and the concomitant use of other drugs (including nicotine in the form of cigarette smoking). "The authors are quite up front about this. The other limitations are the lack of understanding as to what the true denominator is and the under-reporting of the potential numerator, “relates Dr. Erwin to MedPage Today.
The authors report that their findings may be underestimated due to underreporting of events. The researchers write” Despite the known underreporting, the rate of cannabis‐related cardiovascular complications reported steadily rose during the past 5 years.”
‘A prospective study with collection of all cardiovascular cases at hospital admission should complete the present findings, which add to the existing knowledge in the field of cannabis complications and must be considered as the starting point for further research,” write the researchers.
In an accompanying editorial in the journal, Dr. Shereif Rezkalla, MD, FACP, FACC, Department of Cardiology, Marshfield Clinic – Marshfield Center, Wisconsin and Dr. Robert Kloner, MD, PhD, Division of Cardiovascular Medicine, Keck School of Medicine, University of Southern California, Los Angeles, California, highlight the fact that numerous countries and 20 individual states and the District of Columbia in the United States have legalized marijuana for medicinal purposes. In the states of Colorado and Washington use of marijuana for recreational use was legalized and several other states including Alaska, Arizona, Maine, Missouri, Montana, Oregon, and Wyoming have legislation pending.
The doctors write “While the role of medical marijuana is indisputable in patients suffering from chronic, debilitating pain, the potential for widespread legalization of marijuana for recreational purposes raises important questions regarding safety.”
Dr. Rezkalla and Kloner write” this paper does suggest a signal linking cannabis use to cardiovascular events and is deserving of our attention, underscoring the need for more research in this field.”
“As with other medically indicated drugs, use of medical marijuana must be undertaken with cautious consideration of both the benefits and side effects of treatment, they write.
In summary they write “there is clear clinical evidence to suggest a therapeutic benefit of inhaled marijuana for the management of a number of chronic, debilitating conditions. However, clinical evidence also suggests the potential for serious cardiovascular risks associated with marijuana use, including myocardial infarction, serious cardiac arrhythmias, stroke, and even death.”
“It is the responsibility of the medical community to determine the safety of the drug before it is widely legalized for recreational use. It is also important to educate health care providers and the public of the potential risk of developing a cardiovascular event associated with the use of marijuana,” they write in closing.
This study is published in the Journal of the American Heart Association.