Cannabis: the Impact on Vascular Health Viewed Through a Public Health Lens December 8, 2018 1 Faculty Disclosure
Cannabis: The impact on vascular health viewed through a public health lens December 8, 2018 1 Faculty Disclosure
Faculty: Chris Simpson, MD, FRCPC, FACC, FHRS, FCCS, FCAHS Vice-Dean (Clinical), School of Medicine, Professor, Division of Cardiology, Queen's University
Relationships with financial sponsors: • Chris Simpson has no actual or potential conflict of interest in relation to this program
Potential for conflict(s) of interest:
• Chris Simpson has no actual or potential conflict of interest in relation to this program
2 Learning Objectives
After active participation in the workshop, participants will be able to:
1. Understand the historical evolution of medical and recreational marijuana in Canada 2. Summarize the risks and adverse effects of cannabis on vascular health based on the available evidence 3. List potential public health strategies for reducing recreational marijuana use
3 Ancient use of cannabis
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6 Medical marijuana
• Cannabis plant has ~ 400 chemicals; about 70 of which are cannabinoids • Difficult to classify and study • THC and CBD • Low quality evidence exists to support marijuana as a therapeutic agent • Nausea and vomiting during chemotherapy • To improve appetite in patients with AIDS • Improving tics in Tourette’s Syndrome • Anorexia • Pain from arthritis • Glaucoma • Some forms of epilepsy • MS? Movement disorders? Spacticity?
7 Medical authorization
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9 Cannabis
•Cannabis is the generic name for drugs derived from the female Cannabis sativa, Cannabis indica and less commonly Cannabis ruderalis plants. •Delta-9-tetrahydrocannabinol (THC) •Cannabidiol (CBD) •3 main forms: • marijuana, which is a herbal preparation of dried leaves and flowering tops, • hashish, which is produced from the resin of the flowering tops, and • hash oil, produced by solvent extraction of marijuana or hashish.
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11 Symptoms associated with cannabis use
• Euphoria • Increased hunger • Dry mouth • Impaired reaction time • Smoking cannabis stimulates rapid onset of symptoms, with a peak THC serum concentration after 15-30 minutes and duration of 2- 3 hours • Ingesting cannabis delays the onset of action by 30-45 minutes. • Historical THC concentration • 1980: 2% • 2018: 20% and higher
12 PRE-LEGALIZATION FAST FACTS
•3.4 million Canadians have used marijuana within the past year (12%) • Males 2x females •Canadian youth have the highest use amongst developed countries • 28% of 11-15 year olds have used marijuana in the last year •2013: Cannabis accounted for 2/3 of all drug-related arrests (80% of these for possession) •Canadians arrested annually for marijuana possession: 60,000 •Annual cost of enforcement in Canada: $1.2 billion
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14 Risky activities “Acceptable public risk”
Dangerous Regulated Ultra-safe (>1/1000) (<1/100K)
100,000
10,000
1,000
100
10 Total Lives Lost per year per Lost Lives Total
1 10 100 1,000 10,000 100,000 1,000,000 10,000,000 Number of encounters for each fatality Risky activities (Canada)
Dangerous Regulated Ultra-safe (>1/1000) (<1/100K)
100,000
10,000 Driving Offshore rig 1,000 Commercial airlines Coal Mining 100 timber Firearms truckers Rock construction
10 Climbing Bungee Jumping
diving Scuba
Total Lives Lost per year per Lost Lives Total for 25 hrs
1 10 100 1,000 10,000 100,000 1,000,000 10,000,000 Number of encounters for each fatality Risky activities (Canada) “ ” 15,000 deaths/yr Acceptable public risk
Dangerous Regulated Ultra-safe (>1/1000) (<1/100K)
100,000
1/165 risk 10,000 Hospitalisation of death
1,000
100
10 Total Lives Lost per year per Lost Lives Total
1 10 100 1,000 10,000 100,000 1,000,000 10,000,000 Number of encounters for each fatality Medical marijuana versus recreational marijuana
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21 Task Force on Cannabis Legalization and Regulation
22 Effects of cannabis on the cardiovascular system
23 Pacher et al, 2018 Cannabinoid receptors
Kattoor et al, JACC 2016 24
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26 Risk of MI immediately after using marijuana
Mittleman et al, Circulation, 2001
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28 Cannabinoid receptors and platelets
29 Arrhythmia and cannabis
• Sinus tachycardia – sinus bradycardia (chronic use) • High BP (low dose); Low BP (high dose) • Atrial fibrillation • Ventricular tachycardia • Ventricular fibrillation • Brugada – like changes
30 Cannabis and cerebrovascular events
31 Myopericarditis and Takotsubo cardiomyopathy
32 Synthetics
33 Potential benefits of marijuana on cardiovascular health
• Lower obesity rates? • Lower rates of diabetes? • Smoking cessation aid?
• Ultra-low THC preparations limited infarct size in mice
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36 Motor vehicle crashes (MVCs)
37 Cannabis and mental health
38 Respiratory health impacts
39 40 Sales locations
41 Unintended exposure
42 Quality control
43 Marketing and advertising
44 Places of consumption
45 Taxation and pricing
46 Government monopoly versus commercial model
47 Take Home Messages
• The endocannabinoid system (ECS) is complex; the impact of cannabis consumption on bodily systems is poorly understood.
• There is limited, and generally poor-quality evidence, that medical marijuana may provide benefit in a limited list of conditions.
• No good evidence exists that marijuana provides benefit to cardiovascular health (though many therapeutic targets should be studied) and the balance of evidence suggests there may be harm.
• The legalization of recreational marijuana, while potentially advantageous from an economic and law enforcement perspective, poses public health risks which can be mitigated.
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49 50 Questions?
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