Marijuana (THC) Can Affect Heart Health in Elderly
"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 risks and side effects," said Alexandra Saunders from the Dalhousie University in Canada. The study that was published in the Canadian Journal of Cardiology examined the case of an elderly patient who developed crushing chest pain and myocardial ischemia after consuming almost an entire marijuana lollipop.
The "inappropriate dosing and oral consumption of marijuana resulted in distress that caused a cardiac event and subsequent reduced cardiac function," Saunders said.
The report details a 70-year-old man with stable coronary artery disease (a disease that occurs when coronary artery plaque develops and causes a reduction in oxygen supply to the myocardium). He was taking the appropriate cardiac medications and had not experienced a heart problem in more than 2 years.
The man also had osteoarthritis pain and trouble sleeping so he decided to try a lollipop infused with 90mg of THC (delta-9-tetrahydrocannabinol) that's known to act as a pain reliever and aid in sleep. It was his first time trying an edible product and he had not smoked any marijuana since his youth. By ingesting almost all of the 90mg of THC lollipop, he had more than 12 times the dose in a typical joint. Generally a single joint contains only 7mg and the starting dose for a synthetic THC is 2.5mg.
Researchers said, the 70-year-old's consumption of an unusually large amount of THC caused unexpected fearful hallucinations and anxiety, straining his body and likely triggering the cardiac event. The authors called for more research into how different formulations of marijuana might affect the cardiovascular system, particularly among the older population.
Greater studies have connected marijuana to higher risks of stroke and/or heart failure, but a review study published in January of 2018 concluded that there is not currently enough scientific evidence to be able to determine marijuana's effect on the risks of heart problems.
In the editorial that accompanied the study, a professor of medicine at the University of California, San Francisco, Dr. Neal Benowitz, wrote that marijuana could potentially pose heart risks in three different ways: Through direct effects of THC on the cardiovascular system, through inhaling smoke from marijuana, or through the indirect effect of THC that is related to hallucinations and anxiety, such as that in the current case.
There is not enough scientific evidence for doctors to be able to recommend whether someone with heart disease should or shouldn't use cannabis products. The best that Dr. Benowitz could suggest is for patients with heart disease to use products that don't contain THC, only those that contain the compound cannabidiol (CBD) because it does not have the psychoactive effects. If patients want to use marijuana specifically for the effects of THC, he would advise that they try to reduce exposure to the smoke and do not smoke the products. Also, try to take the smallest possible dose to produce the desired benefit.
Dr. Benowitz also noted to be aware some edible products contain more than one "serving" of THC. As for the case above, just a small amount of licks of the 90mg THC lollipop could have provided the best starting dose.
"Understanding appropriate dosing would likely have prevented the toxicity suffered by the patient," Benowitz wrote. "Patients may need counseling as to what constitutes a low dose, and how that compares with the amount of THC in products they may have purchased," he concluded.