Marijuana: Pros and Cons

Transcript

1. Marijuana Legalization: Pros and Cons Stephen B. Greenberg, MD, MACP Chief, Medicine Service Ben Taub Hospital Distinguished Service Professor Baylor College of Medicine Marc Robinson, MD Assistant Professor Baylor College of Medicine Ben Taub Hospital View Slides: bit.ly/SGIMGrandRounds
2. Disclosures No interest or other relationship with commercial interests (drug/device companies) that may relate to the educational content of this activity. View Slides: bit.ly/SGIMGrandRounds
3. Learning objectives • Discuss the history, physiology and current legal status of cannabis • Discuss arguments for and against legalization of marijuana/cannabinoids • Discuss areas of common ground, and a path forward for what needs to be known about the topic View Slides: bit.ly/SGIMGrandRounds
4. Cannabis – A History • Indigenous to Central Asia and Indian Subcontinent • Originally used solely for hemp fibers, as early as the 5th millennium BCE • Psychoactive use noted as early as 1000 BCE in several Indian texts • Use permeated throughout the ancient world Sanskrit on Hemp Paper Moefuzz [CC BY-SA 4.0 (https://creativecommons.org/licenses/by-sa/4.0)] View Slides: bit.ly/SGIMGrandRounds
5. Cannabis – A History "The Scythians, as I said, take some of this hemp-seed, and, creeping under the felt coverings, throw it upon the red-hot stones; immediately it smokes, and gives out such a vapour as no Grecian vapour-bath can exceed; the Scyths, delighted, shout for joy, and this vapour serves them instead of a water-bath; for they never by any chance wash their bodies with water. ” – Herodotus, Histories, IV View Slides: bit.ly/SGIMGrandRounds
6. Cannabis • Grows throughout temperate and tropics • Polytypic – C. sativa, C. indica, C. ruderalis • Can grow at altitudes of 8,000 feet • Can grow at 15 cm/day • Requires little water • Prefers open ground and direct sunlight • Male plant – taller and flowers are smaller • Female flowers – grows tightly together to form cluster
7. Effects of THC on the Brain 1. http://headsup.scholastic.com/students/endocannabinoid 2. Garth E. Terry et al. J Nucl Med 2010;51:112-120
8. Types of Cannabinoids 1. Life Sci. 2005 Dec 22;78(5):454-66. View Slides: bit.ly/SGIMGrandRounds
9. Cannabis • Can be consumed in several forms: – Inhaled: Vaped or smoked: Quicker onset, higher peaks – Edible: Slow onset, lower peaks – Dermal: Variable onset View Slides: bit.ly/SGIMGrandRounds
10. Cannabis THC Concentration Over Time Biol Psychiatry. 2016 Apr 1; 79(7): 613–619
11. Recent U.S. History • The Marijuana Tax Law (1937) • United States “Marihuana” production permit (WW2) • National Commission on Marijuana and Drug Abuse (1972) View Slides: bit.ly/SGIMGrandRounds
12. Medical Marijuana Laws (MML) • 33 states & DC have laws legalizing the use of marijuana for medical purposes • Specific provisions vary considerably • Restrictiveness of these laws varies • 2009 - U.S. Attorney General issued a memoranda instructing federal prosecutors NOT to prioritize prosecution of individuals compliant with state MML From Hasin DS. US Epidemiology of Cannabis Use and Associated Problems. Neuropsychopharmacology 2018 Jan;43(1):195-212. View Slides: bit.ly/SGIMGrandRounds
13. Recreational Marijuana Laws (RML) • 2012 - Colorado and Washington • 2014 - Alaska, Oregon, DC • 2016 - California, Nevada, Massachusetts and Maine • 2018 - Michigan, Vermont From Hasin DS. US Epidemiology of Cannabis Use and Associated Problems. Neuropsychopharmacology 2018 Jan;43(1):195-212. View Slides: bit.ly/SGIMGrandRounds
14. Marijuana Legalization – Pros • Medical Benefits • Public Health Benefits View Slides: bit.ly/SGIMGrandRounds
15. Legalization: Medical Benefits • Narrow FDA Approved Indications o Chemotherapy induced Nausea and Vomiting o Dronabinol ( Marinol, Syndros ) o Nabilone (Cesamet) o Anorexia/Weight Loss Associate with AIDS o Dronabinol - (Marinol, Syndros ) o Lennox-Gastaut syndrome or Dravet syndrome o CBD (Epidiolex) 1. FDA and Marijuana: Questions and Answers. https://www.fda.gov/newsevents/publichealthfocus/ucm421168.htm View Slides: bit.ly/SGIMGrandRounds
16. • Most studies performed use Nabiximols (extract of THC/CBD), a legal form in the UK • Moderate quality evidence to support the use for chronic pain and spasticity • Lower quality for chemotherapy induced nausea and vomiting, cachexia from AIDS 1. Whiting PF et al. JAMA 2015;313(24):2456–73. Legalization: Medical Benefits
17. 1. Whiting PF et al. JAMA 2015;313(24):2456–73. 2. Andreae MH, Carter GM, Shaparin N, et al. J Pain 2015;16(12):1221–32. Chronic Pain: Cannabinoid vs Placebo • Meta-analysis (1 inhaled, 7 oral) • Improvement in symptoms – OR 1.41 (0.99 – 2.00) Chronic Neuropathic Pain: Inhaled Cannabis vs Placebo • Meta-analysis (9 study groups) • Improvement in symptoms – OR 3.22 (1.59 – 7.24) Legalization: Medical Benefits View Slides: bit.ly/SGIMGrandRounds
18. • States with expansion of marijuana laws have decreased opioid prescribing 1. Wen H, Hockenberry JM. JAMA Intern Med 2018;178(5):673–9. Legalization: Public Health Benefits Effect on States with Medical Marijuana Laws Effect on States with Adult Use Laws
19. Legalization: Public Health Benefits 5.88% lower rate of opioid prescribing associated with states that have medical marijuana laws 6.38% lower rate of opioid prescribing associated with states that have adult- use marijuana laws 1. Wen H, Hockenberry JM. JAMA Intern Med 2018;178(5):673–9. View Slides: bit.ly/SGIMGrandRounds
20. • Medicare Database: o 3.7 million fewer daily doses annually in states with dispensary medical cannabis laws (1.7 million fewer for home cultivation) o Hydrocodone: 2.3 million fewer daily doses/year o Morphine: 0.360 million fewer daily doses/year Bradford AC, Bradford WD, Abraham A, Adams GB. JAMA Intern Med 2018;178(5):667–73. Legalization: Public Health Benefits View Slides: bit.ly/SGIMGrandRounds
21. • The biggest risk of using marijuana is the legal ramifications of getting caught • Incarceration has been shown to have multiple negative effects on an individual’s health Annual MJ arrests of convictions by state From, http://www.drugpolicy.org/legalization-status-report Legalization: Public Health Benefits View Slides: bit.ly/SGIMGrandRounds
22. "Medicine is a social science, and politics is nothing but medicine on a large scale. The physicians are the natural attorneys of the poor, and the social problems should largely be solved by them.” – Rudolf Virchow Legalization: Public Health Benefits View Slides: bit.ly/SGIMGrandRounds
23. Med-Peds Grand Rounds: “Incarceration as Social Determination of Health” Marc Robinson, MD January 15th, 12:15pm M323 Legalization: Public Health Benefits
24. Marijuana Legalization – Cons View Slides: bit.ly/SGIMGrandRounds
25. Marijuana How can it affect your health? Addiction: • About 1 in 8 cannabis users will develop Cannabis Use Disorder, prevalence decreases with age • Gateway Drug? – Sequential Gateway Model vs Common liability 1. From Marijuana and Public Health. CDC. https://www.cdc.gov.marijuana/faqs/is-marijuana-medicine.html 2. Center for Behavioral Health Statistics and Quality, 2016 National Survey on Drug Use and Health
26. Marijuana How can it affect your health? Brain Health: • Directly affects parts of the brain responsible for memory, learning, attention, decision making, coordination, emotions, and reaction time. • Heavy users of marijuana can have short-term problems with attention, memory, and learning. Effects may be time limited. • Decreased size of hippocampus with chronic use 1. Marijuana and Public Health. CDC. https://www.cdc.gov.marijuana/faqs/is-marijuana-medicine.html 2. JAMA Psychiatry. 2018;75(6):585.
27. Marijuana How can it affect your health? 1. JAMA Psychiatry. 2018;75(6):585.
28. Marijuana How can it affect your health? 1. JAMA Psychiatry. 2018;75(6):585.
29. Marijuana How can it affect your health? Brain Health: • Earlier use onset, and higher intensity of use is associated with more durable impairment. 1. Clin Psychol Rev. 2014 Nov;34(7):531-50
30. Marijuana How can it affect your health? Lung Health: • Long-term impairment of lung function hasn’t been shown in (low quality) studies • Chronic cough is reported • No association with lung cancer when adjusted for tobacco use 1. Arch Intern Med. 2006;166(13):1359.
31. Marijuana How can it affect your health? Lung Health: • Compared with tobacco: – 5-fold increase in blood carboxyhemoglobin levels – 3-fold increase in inhaled tar – retention of one third more inhaled tar in the respiratory tract. • Long-term impairment of lung function hasn’t been shown in (low quality) studies • No association with lung cancer when adjusted for tobacco use 1. Arch Intern Med. 2006;166(13):1359.
32. Marijuana How can it affect your health? 1. https://www.cdc.gov/tobacco/basic_information/e- cigarettes/severe-lung-disease.html 2. Ann Int Med. 2019 Jan 9; 170(2): 119. • Over 2000 hospitalizations and 48 deaths from electronic cigarette, or vaping, product use associated lung injury (EVALI) • Related to black market vaping products, majority containing THC (eg. Dank Vapes) • Vitamin E acetate identified from the lungs of patients
33. • Evidence shows that marijuana is associated with increased sympathetic drive, risk for myocardial infarction and acute coronary syndrome, decreased time to angina, and increased mortality Ann Int Med. 2019 Jan 9; 170(2): 119. Marijuana How can it affect your health? Cardiovascular Health:
34. Marijuana How can it affect your health? Mental Health: • Cannabis induced psychosis – 41.2% conversion rate to schizophrenia (HR 101.7) • Extensive evidence that marijuana use is associated with development of schizophrenia – Dose dependent, worse with earlier onset of use 1. Am J Psychiatry. 2018;175(4):343.
35. Marijuana How can it affect your health? Hyperemesis syndrome: • Problem of patients with chronic prolonged use (usually daily, usually for several years) • About half will experience some relief with hot baths/showers • Caveat: Many patients with cyclic vomiting syndrome will self medicate with cannabis 1. Mayo Clin Proc. 2012 Feb;87(2):114-9. 2. Clin Gastroenterol Hepatol. 2019 Jul 25
36. Marijuana How can it affect your health? Poisoning: • After legalization, Colorado found a 34% increase in calls to poison control for pediatric exposure (6 of 100, 000) 1. JAMA Pediatr. 2016;170(9) • ~Half were edible formulations • 41% were not stored in a child- proof container or involved poor supervision
37. Marijuana & Pregnancy Adverse neonatal outcomes: • Decrease in birthweight, higher rates of premature delivery, higher rates of NICU admissions Adverse childhood outcomes: • Impaired neurodevelopmental outcomes: attention, hyperactivity, visuospatial function **Studies are old, involving lower potency marijuana, so outcomes are probably worse now.** 1. Pharmacol Ther. 2018;182:133 2. JAMA. 2019;322(2)
38. From Volkow ND et al. Adverse Health Effects of Marijuana Use. N Engl J Med 2014 June 5;370:2219-2227 Level of Confidence in the Evidence for Adverse Effects of Marijuana on Health and Well – Being *The overall level of confidence in the association between marijuana use and the listed effects is an attempt to rank the strength of current evidence, especially with regard to heavy or long-term use/use that starts in adolescence Evidence for Adverse Effect on Health and Well - Being Level of confidence Addiction to marijuana and other substances High Diminished lifetime achievement High Symptoms of chronic bronchitis High Motor vehicle accidents High Abnormal brain development Moderate Progression to other drugs Moderate Schizophrenia Moderate Depression or anxiety Moderate Lung Cancer Low
39. Legalization - Pros • Overstated Risk of Harm
40. Imagine a drug that was responsible for…. • 56,000 emergency room visits per year • 26,000 hospitalizations per year • 458 deaths per year • Available on every street corner in America 1. Nourjah P, Ahmad SR, Karwoski C, Willy M. Pharmacoepidemiol Drug Saf 2006;15(6):398–405. Legalization Overstated Risk of Harm
41. • Some studies show an increase in drivers testing positive for cannabis use • Individual test subjects drive worse under the influence of marijuana 1. Teixeira PGR, Mardock AL, Luftman KM, et al. Am J Public Health 2017;107(8):1329–31. 2. Santaella-Tenorio J, Mauro CM, Wall MM, et al. Am J Public Health 2017;107(2):336–42. Legalization Overstated Risk of Harm
42. • No increase in crash fatality rates in Washington and Colorado after legalization • States with medical marijuana laws showed a decrease in traffic fatalities from 1985 - 2014 1. Teixeira PGR, Mardock AL, Luftman KM, et al. Am J Public Health 2017;107(8):1329–31. 2. Santaella-Tenorio J, Mauro CM, Wall MM, et al. Am J Public Health 2017;107(2):336–42. Legalization Overstated Risk of Harm
43. • Will use increase among teens after legalization? • Survey Data of Teens (compared Colorado, Washington, control states) • Washington: Decreased in perceived harmfulness, increase in use following legalization • Colorado: No decrease in perceived harmfulness, no increase in use 1. Cerdá M, Wall M, Feng T, et al. JAMA Pediatr 2017;171(2):142–9. Legalization Overstated Risk of Harm
44. • With the exception of accidental pediatric overdoses, there have been no reported cases of death from cannabis overdose • Do not know the amount of cannabis related deaths, but it is certainly lower than: o Alcohol: 88,000 deaths/yr o Tobacco: 480,000 deaths/yr o Opioid (overdoses alone): 17,000 deaths/yr 1. CDC.GOV Legalization Overstated Risk of Harm
45. Pros: • Cannabinoids can help with chronic pain, chemotherapy side effects, and some seizure disorders • Expanded marijuana laws decrease opioid prescribing • Many of the harms of marijuana/cannabinoids are somewhat overstated • Teen use could be mitigated with educational strategies Conclusion
46. Cons: • Marijuana is addictive, a problem made worse by legalization • Frequent, prolonged use is associated with cognitive impairment and increased risk of schizophrenia • Black market vaping products are associated with an increased risk of EVALI • Adverse outcomes from use during pregnancy are well documented Conclusion
47. Common areas of agreement: • Marijuana is addictive and chronic use should be addressed • Inhaled forms are more harmful than non-inhaled forms. • Early onset of use is more harmful so all efforts to curb adolescent use should be taken • Potency should be regulated Conclusion
48. Six Policy Lessons Relevant to Cannabis Legalization From Shover CL, Humphreys K Am J Drug Alcohol Abuse. 2019 Mar 14: 1-9. ePublished Ahead of Print • DO NOT have a medical marijuana system that is not truly medical • Protect science, regulation, and public health from corporate influence • Cap the potency of cannabis products • Price may be the most effective lever to promote public health • Look beyond reducing marijuana possession arrests • Facilitate rigorous research .
49. Contraindications and Precautions Associated with High Use of Tetrahydrocannabinol From Maida V and Daeninck PJ. A User’s Guide to Cannabinoid Therapies in Oncology. Curr Oncol. 2016 Dec; 23(6):398-406. • Age <25 • Pregnancy and lactation • Schizophrenia • Psychosis w/recreational cannabis • Compromised cardiac status • History of substance or alcohol abuse Contraindications • Driving motor vehicles • Operating industrial equipment • Use of sedatives or hypnotics • Hypotension • Smoking tobacco heavily • Using strong CYP 3A4 inhibitors† Precautions †Clarithromycin, ketoconazole, indivanir, lopanivir, ritonavir
50. Questions