Researchers are recommending routine screening of marijuana use in cardiovascular care settings.
A review of current evidence suggests an association between marijuana use and adverse cardiovascular effects, as well as interactions between marijuana and cardiovascular medications.
Although more research is needed, the review authors suggested patients may benefit from marijuana screening and testing as well as discussions about the potential risks of marijuana use in the setting of cardiovascular disease.
Ersilia M. DeFilippis, MD, of Columbia University Irving Medical Center in New York and colleagues conducted this review, which was published in the Journal of the American College of Cardiology.
The authors noted that research on marijuana use and cardiovascular disease is limited. The different forms of cannabis and various routes of administration have made it difficult to draw concrete conclusions about marijuana products. Additionally, there have been no randomized, controlled trials of marijuana products in the United States because such trials are illegal; however, there are observational studies linking marijuana use and adverse cardiovascular effects.
Snapshot of available evidence
One study showed that smoking marijuana produces many of the same cardiotoxic chemicals produced by smoking tobacco (BMJ. 2003 May 3;326:942-3). Another study suggested marijuana smokers may have greater exposure to harmful chemicals (J Psychoactive Drugs. 1988 Jan-Mar;20:43-6).
More specifically, a meta-analysis suggested that smoking marijuana was one of the top three triggers of myocardial infarction (Lancet. 2011 Feb 26;377:732-40). And in a systematic analysis, 28 of 33 studies linked marijuana use to an increased risk of acute coronary syndromes (Clin Toxicol [Phila]. 2019 Oct;57:831-41).
Furthermore, a study of 2.5 million marijuana users showed that 3% experienced arrhythmias (Int J Cardiol. 2018 Aug 1;264:91-2). A population survey showed that people who smoked marijuana in the past year experienced a 3.3-fold higher rate of cerebrovascular events (Aust N Z J Public Health. 2016 Jun;40:226-30).
Studies have also indicated that cannabinoids can affect cardiovascular medications, including antiarrhythmics, calcium-channel blockers, isosorbide dinitrate/mononitrate, statins, beta-blockers, warfarin, theophylline, and nonsteroidal anti-inflammatory drugs (Medicines [Basel]. 2018 Dec 23;6 pii: E3; Curr Top Behav Neurosci. 2017;32:249-62; Pharmacogenet Genomics. 2009 Jul;19:559-62; Ann Pharmacother. 2009 Jul;43:1347-53; Pharmacol Ther. 2019 Sep;201:25-38).
Cardiovascular specialists should be informed about regulations governing marijuana products, as well as “potential health consequences of marijuana and its derivatives,” according to Dr. DeFilippis and colleagues.
The authors recommend routinely screening patients for marijuana use, perhaps using the Daily Sessions, Frequency, Age of Onset, and Quantity of Cannabis Use Inventory (PLoS One. 2017 May 26;12:e0178194) or the Cannabis Abuse Screening Test (Int J Methods Psychiatr Res. 2018 Jun;27:e1597).
The authors say urine toxicology “may be reasonable” for patients with myocardial infarction or new-onset heart failure. Such testing is required for patients undergoing a heart transplant because marijuana use may affect their candidacy.
Dr. DeFilippis and colleagues say cardiovascular specialists should inform patients about the risks associated with marijuana use. The authors recommend shared decision making for patients who use marijuana for symptom management or palliative purposes.
Three review authors disclosed relationships with many different pharmaceutical companies. One author disclosed relationships with Medscape Cardiology and WebMD, which are owned by the same parent company as MDedge.
SOURCE: J Am Coll Cardiol. 2020 Jan 20. doi: 10.1016/j.jacc.2019.11.025.