Pot And Strokes: What's The Real Link?

Marijuana has been used for its psychoactive properties for thousands of years. In recent years, its recreational use has been legalized in many places, and its consumption has increased significantly. However, there is growing evidence of a link between cannabis use and an increased risk of cardiovascular problems, including strokes. While the exact mechanism by which cannabis may cause strokes is not yet fully understood, studies have found a higher prevalence of ischemic and hemorrhagic strokes among cannabis users compared to non-users. The risk appears to be higher for those who use marijuana daily and smoke it.

Daily cannabis use is associated with a 42% higher chance of stroke

Cannabis use has been linked to a higher risk of heart attacks and strokes. Daily cannabis users have a 25% higher chance of having a heart attack and a 42% higher chance of having a stroke. This risk is present regardless of whether the user also uses tobacco products or has other underlying cardiovascular risk factors.

The primary psychoactive ingredient in cannabis is delta(9)-tetrahydrocannabinol (THC). THC interacts with CB1 and CB2 receptors, which are widely distributed in the cardiovascular system. Activation of these receptors can modulate the cellular activity of the vessel wall, potentially contributing to the pathogenesis of atherosclerosis.

There is also evidence of a link between cannabis and ischemic stroke (IS). A study of 218 New Zealanders found that 15.6% of those with IS or transient ischemic attack (TIA) tested positive for cannabis use, compared to 8.1% of control participants. Another review of the literature identified 59 cases of cannabis-related stroke, with the majority being IS.

The mechanism by which cannabis may cause IS is not yet fully understood, but there are several theories. In addition to the potential development of atherosclerosis, THC may trigger reversible cerebral vasoconstriction syndrome (RCVS). Animal studies have shown that THC has peripheral vasoconstrictor properties.

While the therapeutic benefits of cannabis have not been conclusively established, there is growing evidence of its harmful effects, particularly regarding cardiovascular health. The American Heart Association recommends that practitioners and clinicians assess cannabis use at each patient encounter to discuss potential cardiovascular risks and ways to reduce them.

Cannabis smoke is similar to tobacco smoke, but with THC instead of nicotine

Cannabis and tobacco smoke are similar in that they both contain many of the same carcinogens and tumour promoters, such as polycyclic aromatic hydrocarbons. The simple truth is that burning plant matter produces a lot of harmful chemicals, regardless of the plant. However, there are also some differences between the two types of smoke. For instance, tobacco smoke is known to contain over 7,000 chemicals, with around 70 of them being carcinogenic, whereas cannabis smoke contains cannabinoids instead of nicotine.

Tobacco smoke is linked to over 400,000 deaths per year in the United States, with over 140,000 of those being lung-related. Although cannabis smoke has been linked to respiratory issues, it has not been directly linked to tobacco-related cancers such as lung, colon, or rectal cancers.

The risks of smoking marijuana are not as well-established as those of smoking tobacco, but they are still present. For example, marijuana smoking is linked to a higher likelihood of coughs, wheezing, airway inflammation, and sputum production. However, the impact on general lung function has not been consistently demonstrated.

In conclusion, while both tobacco and cannabis smoke have similar chemical properties, their pharmacological activities differ. Components of cannabis smoke minimize some carcinogenic pathways, whereas tobacco smoke enhances them. Tobacco smoke increases the likelihood of carcinogenesis by overcoming normal cellular checkpoint protective mechanisms through the activity of respiratory epithelial cell nicotine receptors. On the other hand, cannabinoid receptors have not been reported in respiratory epithelial cells, meaning that the DNA damage checkpoint mechanism should remain intact after prolonged cannabis exposure. Furthermore, nicotine promotes tumour angiogenesis, while cannabis inhibits it.

THC interacts with CB1 and CB2 receptors, which are widely distributed in the cardiovascular system

THC, the primary psychoactive ingredient of cannabis, interacts with CB1 and CB2 receptors, which are widely distributed in the cardiovascular system. CB1 receptors are particularly abundant in the frontal cortex, hippocampus, basal ganglia, and cerebellum. Activation of CB1 receptor inhibits the release of amino acid and monoamine neurotransmitters, leading to the "high" associated with cannabis.

CB1 and CB2 receptors are also found in the cardiovascular system, where they modulate the cellular activity of the vessel wall, which may contribute to the pathogenesis of atherosclerosis. CB1 expression has been identified in macrophages of advanced atheromas. Atherosclerotic coronary artery sections from patients with unstable angina have shown significantly higher expression of CB1 receptors in comparison to those with stable angina. THC has also been shown to activate platelets via CB1 and CB2 receptors, leading to increased GPIIb-IIIa expression and activation of factor VII, a potent thrombogenic protein.

Cannabis use is linked to a higher risk of heart attacks and strokes, regardless of tobacco use

Cannabis use has been linked to a higher risk of heart attacks and strokes, regardless of tobacco use. This conclusion is supported by a study published in the Journal of the American Heart Association, which found that cannabis users had a higher risk of cardiovascular problems, even when compared to those who used tobacco products or had underlying cardiovascular risk factors.

The study analyzed survey data from 434,104 US adults and found that any marijuana use was associated with a higher risk of heart attacks and strokes, with daily users having 25% higher odds of a heart attack and 42% higher odds of a stroke. The researchers also found that among men under 55 and women under 65, using marijuana resulted in a 36% higher combined odds for coronary heart disease, heart attack, or stroke, regardless of tobacco use.

The primary psychoactive ingredient in cannabis, delta(9)- tetrahydro-cannabinol (THC), interacts with CB1 and CB2 receptors in the cardiovascular system. Activation of these receptors can modulate the cellular activity of the vessel wall, contributing to the pathogenesis of atherosclerosis. THC has also been linked to increased platelet activation, which can lead to a higher risk of blood clots and subsequent cardiovascular events.

While the exact mechanism by which cannabis may cause ischemic stroke is not fully understood, there are several theories. In addition to the development of atherosclerosis, THC may trigger reversible cerebral vasoconstriction syndrome (RCVS). Animal studies have shown that THC has peripheral vasoconstrictor properties, which could contribute to reduced blood flow to the brain and subsequent ischemic stroke.

The growing evidence of a link between cannabis use and an increased risk of cardiovascular events highlights the importance of assessing cannabis use during patient encounters to have informed conversations about potential risks and ways to reduce them.

The risk of stroke is higher in chronic users than occasional users

Cannabis Use and Risk of Stroke

Cannabis sativa, commonly known as marijuana, has been used for its psychoactive properties for thousands of years. While some advocate for its medicinal benefits, there is growing evidence of its harmful effects, particularly its association with an increased risk of stroke.

Cannabis and the Risk of Ischemic Stroke

Ischemic stroke, similar to a heart attack, occurs when blood vessels in the brain become blocked by clots. A 2008 survey found that out of 102 million Americans who have used marijuana, 15 million use it regularly. A study of 218 New Zealanders with ischemic stroke or transient ischemic attack (TIA) found that 15.6% tested positive for cannabis use compared to 8.1% in the control group. After adjusting for age, sex, and ethnicity, cannabis use was linked to a higher risk of ischemic stroke or TIA. However, when tobacco use was taken into account, an independent association could not be established.

A review by Wolff et al. revealed 59 cases of cannabis-related stroke, with ischemic stroke being the most common type (83%). The mean age of the participants was 33 years, and the ratio of men to women was 4.9 to 1. In this review, ischemic stroke was more frequent in chronic users than occasional users. Additionally, several reports indicated that the stroke occurred while the drug was being smoked or shortly after.

Cannabis and the Risk of Hemorrhagic Stroke

Hemorrhagic stroke occurs when a blood vessel in the brain breaks or ruptures, leading to blood seeping into the brain tissue and damaging brain cells. While ischemic stroke is primarily associated with cannabis use, there is also evidence of a link between cannabis and hemorrhagic stroke. In a study involving 3,185,560 people with cannabis use, the prevalence of hemorrhagic stroke was 0.3%, higher than the 0.2% prevalence observed in those without cannabis use.

While the exact mechanism by which cannabis may cause stroke is not fully understood, the available evidence suggests that chronic cannabis users are at a higher risk of stroke than occasional users. The risk of ischemic stroke, in particular, appears to be elevated in chronic users. However, more research is needed to establish a causal relationship and understand the underlying biological mechanisms.

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