Health Impact of Cannabis: Adolescents

Transcription

1 Health Impact of Cannabis: Adolescents Leslie R. Walker-Harding, MD National Academies committee on the Health Effects of Marijuana Meeting August 18, 2016

2 THC on the Human Brain NIDA

3 Cannabis/Marijuana Cannabis is a depressant and a hallucinogen Cannabis is an addictive substance Smoked in paper, pipes, bongs, water bongs, vaporizers Oils, pastes, butane infused Added to food/drinks Levels of THC (delta 9-tetrahydrocannaboid) THC levels in the 1960 between 0.5%- 3% Current THC between 12% - 25%+

4 KNOWN HEALTH EFFECTS

5 Acute Health Effects Increased heart rate 20 to 100 times normal 4.8 fold increase in chance of having a heart attack within 1 st hour after using drug ( Mittleman 2001) Euphoria, relaxation, change in pain sensation Distorted sensory perception Thought and time distortion Slowed reaction time to stimuli Hallucinations, paranoia, anxiety, psychosis Memory impairment Excessive vomiting

6 Regular Adolescent Use o Dependence in 1 in 6 teens who use regularly o Craving and Tolerance leads to increased usage over time o Withdrawal symptoms o Chronic bronchitis and impaired respiratory function in regular smokers o Psychotic symptoms and disorders in heavy users, especially those with a history of psychotic symptoms or a family history of these disorders o Strong connection between Schizophrenia o Teens who use marijuana and alcohol together have 50-90% more car accidents o Marijuana users use more cigarettes and other drugs than those who do not use marijuana

7 Marijuana s Long Term Effects Short-term memory impairment that is long lasting Likely permanent cognitive impairment and loss of IQ in adolescents who begin use at an early age and continue into late adolescence Poorer psychosocial development Impaired educational attainment in adolescents who are regular users Associated with high school drop out Poorer treatment outcomes

8 Source: Meier et al. Proceedings of the National Academy of Sciences Available at:

9 Mj dependent 3+ yrs Average IQ change: Never used 99.8 to MJ dependent 3+ yrs 99.7 to 93.9 Mj dependent 2 yrs Mj dependent 1 yr Used, never diagnosed Never used Source: Meier et al. PNAS, 2012

10 Association between cannabis use and schizoaffective disorder Never used cannabis Ever used cannabis >50 times # Exposure # Cases HR Crude HR adjusted* 39, , (1.13.8) 0.8 (.2-2.9) ( ) 7.4 ( ) * Adjustments for: prior personality disorders at conscription, IQ, disturbed behavior in childhood, social adjustment, risky use of alcohol, smoking, early adulthood socioeconomic position, use of other drugs, brought up in a city. The category Ever used cannabis includes all individuals who reported cannabis use, including those who reported >50 times. Griffith-Lendering, Addiction, 108(4), Manrique-GarciaBMC Psychiatry, 12, 112.

11 CURRENT TRENDS

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13 Adolescent health impact Overdoses Source: WA Poison Center, July 2015 Source: WA Poison Center, January 2015

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15 Secondhand Marijuana Smoke Rats with impaired endothelial wall function after 1 minute and took longer to recover than cigarette smoke Wang 2016 Secondhand MJ Smoke detected in adults Cone 1987 Extreme exposure to adults causes mild intoxication Hermann in 6 infants and toddlers admitted for respiratory compromise had traces of MJ in their system. Wilson 2016

16 Seattle Public Schools Disciplinary Actions 876 drug-related disciplinary actions 98% of non-alcohol actions were for marijuana Tobacco Possession 3% Possess/ Under the Influence of Alcohol 11% Selling Drugs 2% Selling Alcohol <1% Distributing Drugs 3% Distributing Alcohol 2% Safety & Security Data Drug-related infractions: : : : : 258 Drug-related items filled SPS safe plus new cabinet. Possess/ Under the Influence of Drugs 79% Five high school students required medical attention after overdosing on marijuana-infused foods at school.

17 Current Challenges Better document effects on infants children and adolescents, under 25 vs adult effects (i.e. secondhand smoke) Measurement techniques need to be calibrated for higher circulating levels Studies need to use higher THC concentrations. It is possible that the higher the THC circulating concentration, the more associated effects: anxiety addiction, psychosis, hyperemesis, etc. Edibles vs smoking do they have the same effects? Use patterns in those adolescents with chronic illness Industrialization and perception of risk Increased use in certain populations

18 Committee s Report Clear distinction between maternal/child, adolescent, young adult and older adult Clarification of the addictive properties of cannabis Addressing the inappropriateness of comparing cannabis to other drugs Addressing the need for more research on effects of cannabis with industry level products Addressing the populations who are seeing large shifts in usage over the last decade

19 Marijuana Strength

20 Dabbing

21 Slides not in presentation

22 Volkow NIDA 2014

23 THC reduces hippocampal neuron activation With chronic THC exposure, neurons are gradually lost due to continual suppression THC users have smaller hippocampuses, and poorer memory Source: Iversen L. How cannabis works in the brain. In Marijuana and Madness. Ed. Castle & Murray, Oxford University Press.

24 PET scans of the brain on marijuana Brookhaven National Laboratory Center for Imaging and Neurosciences, Behavioral, Pharmacology & Neuroimaging Lab, Upton, New York.