Transcript Impacts of Marijuana Use on Adolescents

By Deborah Williams
AYDC
1. The Adolescent Brain: A
period of tremendous biological change
 2. What science is telling us about impacts of
marijuana on the developing brain
 3. Youth Perceptions of Marijuana Harm
 4. Protective Factors
 5. Commercialization
Of Marijuana- A Glimpse

What’s next

Neurons (Grey Matter):
Carry information
through
electrochemical
processes – 100 billion

Astrocyte (Astroglia): Star-shaped cells that provide physical and

Microglia: Like astrocytes, microglia digest parts of dead neurons.

nutritional support for neurons: 1) clean up brain "debris"; 2) transport
nutrients to neurons; 3) hold neurons in place; 4) digest parts of dead
neurons; 5) regulate content of extracellular space; 6) neurogenesis
Oligodendroglia: Provide the insulation (myelin) to neurons in
the central nervous system.

Satellite Cells: Physical support to neurons in the peripheral nervous system.

Schwann Cells: Provide the insulation (myelin) to neurons in the peripheral
nervous system.
( Eric Chudler, University of Washington)


1. “Striking (brain)
changes take place
during the teen years.”
(National Institute of
Mental Health)
2. Spurt of neuron (grey
matter) growth in frontal
cortex before puberty,
and then a pruning of
neurons and wrapping of
white matter (myelin)
around other
connections to stabilize
and strengthen them.
Rewiring, strengthening,
pruning, organizing.

"Studies of normal
brain development
reveal critical areas of
the brain that develop
during late
adolescence, and our
study shows that heavy
cannabis use is
associated with
damage in those brain
regions," said study
leader Manzar Ashtari,
Ph.D., director of the Diffusion
Image Analysis and Brain Morphometry
Laboratory in the Radiology Department
of The Children's Hospital of
Philadelphia. (Science News (2009))

http://www.dampkring
.nl/files/post/23c59db
6z11fc4459b8dz7277_
500_457.jpg?id=1365_
9


.
“Our finding indicate long-term cannabis use is
hazardous to the white matter of the developing
brain.” “Microstructural impairment” (Zalesky,
et.al. (2012)).
“Long-term heavy cannabis use in healthy
individuals is associated with smaller cerebellar
white-matter volume similar to that observed in
schizophrenia. Reduced volumes were even more
pronounced in patients with schizophrenia who
use cannabis.” (Solowij, et.al (2011)).


Astrocytes, a type
of glia, have a
principal role in
working memory.
Marijuana impairs
glial cells (Scientific
American (2012))
“For those who met criteria for cannabis
the average drop in IQ
was 8 points (between age 13 and 38)…
dependence…,
The decline in IQ included all four indices of IQ:
working memory, processing speed, perceptual
reasoning and verbal comprehension”
(“Persistent cannabis users show neuropsychological decline
from childhood to midlife,” Meier, et. al.(2012)) ruled out preexisting difference in IQ; also showed that those who used marijuana
heavily before age 18 showed mental decline even after they quit
consuming.





“In conclusion, the
available evidence
support the hypothesis
that cannabis is an
independent risk
factor, both for
psychosis and the
development of
psychotic symptoms.”
(“Cannabis as a risk
factor for psychosis:
systematic review,”
Semple, et.al.(2005))

“Smoking high
amounts of cannabis
(in adolescence) is
associated with
increased levels of all
three symptom
dimensions:
psychotic, negative
and depressive.”
(“Cannabis use at a young
age is associated with
psychotic experiences,”
Schubart, et.al.(2011)).
“We found a dose–response relationship
between the amount of cannabis use and the
odds for psychiatric hospitalization.
 Adjusted odds ratios for hospitalization
increased with the amount of cannabis
consumed.
 Exposure to cannabis before the age of 12
years was found to carry a 4.8 (95% CI: 2.9–
7.8) times increased odds for past psychiatric
hospitalizations.
(Schubart, et.al. (2011)).


Replication in two
independent
population-based
samples that
childhood
maltreatment and
cannabis use
synergistically impact
on psychosis risk.
(Konings, et. al.
(2012))

“…the psychosisinducing effects of
cannabis were
stronger in
individuals exposed
to earlier sexual or
physical
mistreatment”
ER admission rates rising
Cannabis-related emergency hospital admission rates
have been rising sharply in the US.
• From an estimated 16, 251 in 1991 to over
374,000 in 2008
Source: SAMHSA, 2011
14


Cortical oscillations are patterns of activity of
neurons in the brain. They are very abnormal
in schizophrenia and other brain disorders.
Scientists exposed adolescent mice to small
amounts of active ingredient in marijuana for
20 days, then allowed them to return to
siblings.




In adult mice (exposed to marijuana ingredients
in adolescents), scientists found
“cortical oscillations were grossly altered, and
they exhibited impaired cognitive abilities…and
impaired cognitive behavioral performance….
The striking finding is that, even though the mice
were exposed to very low drug doses, and only
for a brief period during adolescence, their brain
abnormalities persisted into adulthood.”
(Raver, et.al.(2013))




The researchers reviewed over 120 studies that looked at different
aspects of the relationship between cannabis and the adolescent
brain…
"Data from epidemiological studies have repeatedly shown an
association between cannabis use and subsequent addiction to
heavy drugs and psychosis (i.e. schizophrenia). …When the first
exposure occurs in younger versus older adolescents, the impact of
cannabis seems to be worse in regard to many outcomes such as
mental health, education attainment, delinquency and ability to
conform to adult role," Dr Jutras-Aswad said.
the researchers note that rat models enable scientists to explore and
directly observe the same chemical reactions that happen in human
brains. …As the structure of the brain changes rapidly during
adolescence (before settling in adulthood), scientists believe that the
cannabis consumption at this time greatly influences the way these
parts of the user's personality develop.
(ScienceDaily (8/27/13))



"Of the illicit drugs, cannabis is most used by
teenagers since it is perceived by many to be of
little harm. This perception has led to a growing
number of states approving its legalization and
increased accessibility. ..
…approximately one in four of teenage users of
cannabis will develop an abusive or dependent
relationship with the drug.," Jutras-Aswad said.
(ScienceDaily (8/27/13))

“The study highlights that consuming Cannabis
during pregnancy clearly results in defective
development of nerve cells of the cerebral cortex,
the part of the brain that orchestrates higher cognitive functions and drives
memory formation.


In particular, THC negatively impacts if and how
the structural platform and conduit for
communication between nerve cells, the
synapses and axons, will develop and function.
Researchers also identified Stathmin-2 as a key
protein target for THC action, and its loss is
characterized as a reason for erroneous nerve
growth.” (Study: EMBO Journal 1/2014)
14
12
Average THC and CBD Levels
in the US: 1960 - 2011
MARIJUANA POTENCY
10
8
THC:
Psychoactive
Ingredient
6
4
CBD:
NONPsychoactive
Ingredient
2
0
196 196 197 197 197 198 198 198 198 198 199 199 199 199 199 199 199 199 200 200 200 200 200 200 200 200 200 200 201 201
0 5 0 4 8 0 3 4 5 6 0 2 3 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
THC 0.2 0.2 0.4 0.5 1 1 1.5 3.3 3.3 3.5 3.5 3.1 3.1 4 4.5 5.2 5 4.7 5.4 6.2 7.3 7.2 8.3 8.1 9.1 10 10 9.9 11 11
CBD
0.3 0.3 0.4 0.4 0.3 0.3 0.4 0.4 0.4 0.4 0.5 0.5 0.4 0.5 0.5 0.5 0.5 0.5 0.4
Source: Mehmedic et al., 2010
20
Green Crack
21


Driver culpability studies show that drivers
testing positive to marijuana “are significantly
more likely to be responsible for fatal car
crashes than are drug-free drivers.”
(University of Washington ADAI)
“the acute effect of moderate or higher doses
of marijuana impairs the skills related to safe
driving and injury risk”, particularly
“attention, tracking and
psychomotor skills.”



Nearly two-thirds (65%) of teens who reported
using marijuana at least once in their lifetime
said that legalizing the drug would make them
more likely to use it.
In addition, more than three-fourths (78%) of
heavy marijuana users reported that legalizing
the drug would make them more likely to use it.
Sixteen percent of teens who reported that they
had never used marijuana agreed that they would
be more likely to use marijuana if it were legal.
(Center for Substance Abuse Research from The Partnership for a Drug-Free America
and the MetLife Foundation, The Partnership Attitude Tracking Study (PATS): Teens and
Parents, 2013.)
Increased use among teens
• Among youth (12-17) marijuana use
rates in states with medical
marijuana laws is 8.6% compared to
6.9% in states without such laws
• In states with medical marijuana
laws, adolescents’ perception of the
harmful effects of marijuana have
significantly decreased.
Source: Wall, M., et al., 2011; Johnston,
L.D., et al., 2011.
24
Availability among Teens
• 50% and 44% of youth report that they can
obtain alcohol and cigarettes, respectively,
within a day.
• Youth are least likely to report that they can
get marijuana within a day (31%); 45%
report that they would be unable to get
marijuana at all.
Source: The National Center on Addiction and
Substance Abuse at Columbia
University (CASA), 2012
25


% of Anchorage
students who think
smoking marijuana
regularly is no or
slight risk:
Total: 49.2%
◦ Male: 57.4%;
◦ Female: 40.7%)
(2011 YRBS)
◦ Versus 15.1% of
students who think
smoking one or more
packs of cigarettes per
day is no or slight risk;
◦ Versus 34.5% of
students who think
one or two drinks of
alcohol nearly every
day is no or slight risk

Percentage of
students who
believe their
parents consider it
very wrong for
them to smoke
marijuana
◦ 65.4% (Male: 61%;
Female: 70%)
 Versus 79.3% of
students who believe
their parents consider it
very wrong for them to
smoke cigarettes
 Versus 52.6% of
students who believe
their parents consider it
very wrong for them to
drink alcohol regularly.
The Tobacco Industry Connection
“The use of marijuana ... has important implications for
the tobacco industry in terms of an alternative product
line. [We] have the land to grow it, the machines to roll
it and package it, the distribution to market it. In fact,
some firms have registered trademarks, which are taken
directly from marijuana street jargon. These trade
names are used currently on little-known legal
products, but could be switched if and when marijuana
is legalized. Estimates indicate that the market in
legalized marijuana might be as high as $10 billion
annually.”
From a report commissioned by cigarette manufacturer Brown and
Williamson (now merged with R.J. Reynolds) in the 1970s.
Marijuana-based medicines
• Sativex® is in the process of
being studied in the USA.
• THC:CBD = 1:1
• It is administered via an oral
mouth spray
• Already approved in Canada
and Europe
• Also Epidiolex ®, pure CBD,
no THC
32
Commercialization of
Marijuana
33
Commercialization of
Marijuana
34
Commercialization of
Marijuana
35
A variety of medical marijuana products and
‘edibles’ can be found at dispensaries:
• Brownies, carrot cake, cookies, peanut butter, granola bars, ice
cream.
• Many such as ‘Ring Pots’ and ‘Pot Tarts’ are marketed with
cartoons and characters appealing to children.
36
Really?
Alcohol & Tobacco:
Money Makers or Dollar Drainers?
 For every 1$ gained from alcohol and tobacco tax
revenues, $10 is lost in legal, health, social, and
regulatory costs
$$$$$$$$$$$
Source: Urban Institute and Brookings
Institute, 2012; Tax Policy Center, 2008
38

Will be on the August primary ballot

All about commercialization

Impacts on Youth critical to consider
Deborah Williams
AYDC