Potent marijuana edibles can pose a major unrecognized risk to patients with cardiovascular disease
February 11, 2019
Science Daily/Elsevier
With widespread legalization and increasing use, more care, education a research needed about how each marijuana formulation may affect and sometimes compromise the cardiovascular system of our aging population, according to a new article and editorial.
As marijuana legalization sweeps North America, use of the substance has been on the rise, and the public's attitude is shifting. An increasing number of people believe that "weed" is the safest recreational drug, one that carries health benefits that outweigh its risks. Those assumptions are challenged in an article and editorial published in the Canadian Journal of Cardiology that examine the story of a patient who developed crushing chest pain and myocardial ischemia after consuming most of a marijuana lollipop.
"Marijuana can be a useful tool for many patients, especially for pain and nausea relief. At the same time, like all other medications, it does carry risk and side effects. In a recent case, inappropriate dosing and oral consumption of marijuana by an older patient with stable cardiovascular disease resulted in distress that caused a cardiac event and subsequent reduced cardiac function," said Alexandra Saunders, MD, Dalhousie University, Internal Medicine Program and Horizon Health Network's Department of Cardiology, Saint John, NB, Canada.
The case report describes a 70-year-old man with stable coronary artery disease, taking the appropriate cardiac medications, who ate most of a lollipop that was infused with 90 mg of THC (delta-9-tetrahydrocannabinol) to relieve pain and aid sleep, which caused him to have a potentially-serious heart attack. He consumed a much larger dose than the 7 mg that is typically ingested by smoking a single joint or taking the 2.5 mg starting dose of dronabinol (Marinol), a synthetic THC marketed for nausea and appetite stimulation in AIDS and cancer patients. While the patient had smoked marijuana in his youth, he had not done so since the THC content of the substance had increased significantly from three percent to 12 percent. He was also not familiar with the time-delayed and extended effect of oral THC dosing.
The patient's cardiac event was likely triggered by unexpected strain on his body from anxiety and fearful hallucinations caused by the unusually large amount of THC he ingested. His sympathetic nervous system was stimulated, causing increased cardiac output with tachycardia, hypertension, and catecholamine (stress hormone) release. After the psychotropic effects of the drug wore off, and his hallucinations ended, his chest pain stopped.
A number of prior case reports, as well as epidemiological studies, have described the association between cannabis use and acute cardiovascular (CV) adverse events, including myocardial infarction, stroke, arrhythmias, and sudden death.
"Most previous research on marijuana-induced myocardial ischemia focused mostly on younger patients and did not focus on its different formulations and potencies. As a result of widespread marijuana legalization, healthcare providers need to understand and manage cannabis use and its complications in older patients, particularly in those with cardiovascular disease," said Robert S. Stevenson, MD, Horizon Health Network, Department of Cardiology, Saint John, NB, Canada.
CV toxicity of marijuana is described in an accompanying editorial. It can be viewed as a consequence of one or more the following: 1) inhalation of combustion products of marijuana; 2) direct CV effects of THC; and 3) indirect effects of THC related to acute anxiety, hallucination, and/or psychosis. Individuals who are THC-naïve and are not used to taking mind-altering drugs can become highly distressed by impaired cognition and feelings of loss of control produced by THC. Extreme emotional responses in the context of THC psychiatric toxicity are associated with surges of catecholamines, which can have adverse acute CV effects. Important considerations with respect to cannabis toxicity are the pattern of use, dose, route of administration, and degree of tolerance.
"The legalization of cannabis has considerable public support but also raises public health concerns," commented the editorial's author, Neal L. Benowitz, MD, Chief, Division of Clinical Pharmacology and Experimental Therapeutics, Medical Service, Departments of Medicine, and Biopharmaceutical Sciences; Center for Tobacco Control Research and Education, University of California, San Francisco, CA, USA. "Some users may benefit from the social and medical effects, but others will be at risk for adverse health outcomes. Little information has been disseminated to patients or healthcare providers about cannabis use in older patients, and in particular those with cardiovascular disease. For better or worse, providing advice and care to such patients who are using cannabis is now necessary for the provision of optimal medical care to these patients."
https://www.sciencedaily.com/releases/2019/02/190211083204.htm
Marijuana use associated with increased risk of stroke, heart failure
As marijuana legalization spreads, better understanding of side effects is needed
March 9, 2017
Science Daily/American College of Cardiology
Using marijuana raises the risk of stroke and heart failure even after accounting for demographic factors, other health conditions and lifestyle risk factors such as smoking and alcohol use, according to research scheduled for presentation at the American College of Cardiology's 66th Annual Scientific Session.
Coming at a time when marijuana, medically known as cannabis, is on track to become legal for medical or recreational use in more than half of U.S. states, this study sheds new light on how the drug affects cardiovascular health. While previous marijuana research has focused mostly on pulmonary and psychiatric complications, the new study is one of only a handful to investigate cardiovascular outcomes.
"Like all other drugs, whether they're prescribed or not prescribed, we want to know the effects and side effects of this drug," said Aditi Kalla, MD, Cardiology Fellow at the Einstein Medical Center in Philadelphia and the study's lead author. "It's important for physicians to know these effects so we can better educate patients, such as those who are inquiring about the safety of cannabis or even asking for a prescription for cannabis."
The study drew data from the Nationwide Inpatient Sample, which includes the health records of patients admitted at more than 1,000 hospitals comprising about 20 percent of U.S. medical centers. Researchers extracted records from young and middle-aged patients -- age 18-55 years -- who were discharged from hospitals in 2009 and 2010, when marijuana use was illegal in most states.
Marijuana use was diagnosed in about 1.5 percent (316,000) of more than 20 million health records included in the analysis. Comparing cardiovascular disease rates in these patients to disease rates in patients not reporting marijuana use, researchers found marijuana use was associated with a significantly increased risk for stroke, heart failure, coronary artery disease and sudden cardiac death.
Marijuana use was also linked with a variety of factors known to increase cardiovascular risk, such as obesity, high blood pressure, smoking and alcohol use. After researchers adjusted the analysis to account for these factors, marijuana use was independently associated with a 26 percent increase in the risk of stroke and a 10 percent increase in the risk of developing heart failure.
"Even when we corrected for known risk factors, we still found a higher rate of both stroke and heart failure in these patients, so that leads us to believe that there is something else going on besides just obesity or diet-related cardiovascular side effects," Kalla said. "More research will be needed to understand the pathophysiology behind this effect."
Research in cell cultures shows that heart muscle cells have cannabis receptors relevant to contractility, or squeezing ability, suggesting that those receptors might be one mechanism through which marijuana use could affect the cardiovascular system. It is possible that other compounds could be developed to counteract that mechanism and reduce cardiovascular risk, Kalla said.
Because the study was based on hospital discharge records, the findings may not be reflective of the general population. The study was also limited by the researchers' inability to account for quantity or frequency of marijuana use, purpose of use (recreational or medical), or delivery mechanism (smoking or ingestion).
Kalla suggested that the growing trend toward legalization of marijuana could mean that patients and doctors will become more comfortable speaking openly about marijuana use, which could allow for better data collection and further insights into the drug's effects and side effects.
https://www.sciencedaily.com/releases/2017/03/170309142318.htm