Substance use disorders Flashcards
Economic, societal impacts
$46 billion a year (2017)
Almost $1258 for every person in Canada
Alcohol and tobacco use continue cost more to the economy and
public health that all other substances combined
63% of these costs
More than 66,000 preventable deaths (2017)
What is contributing to the cost?
Lost productivity =$20 billion (44%)
Healthcare costs = $13.1 billion (28%)
Criminal justice = $9.2 billion (20%)
Financial
Employment
Housing
Legal
Learning
Family/marital
Social
Physical health
Safety
substance use continuum
no use
beneficial use
non-problematic
problematic use
potentially harmful
sustance use disorder
In the middle kind of area of this continuum, you can see that substance use can be both beneficial and harmful. So e.g. you may go out and have some drinks with some friends and you feel a little bit sick the next day. So this was this combination of deriving benefit from using a substance and then also having some harm from using a substance.
Substance use disorder - DSM 5
Medical illness caused by repeated misuse of a substance or substances.
Characterized by clinically significant impairments in health, social function, and impaired
control over substance use.
DSM-5 (AMERICAN PSYCHIATRIC
ASSOCIATION, 2013)
susbtance related and addictive disorders:
Alcohol-related disorders
Caffeine related disorders
Cannabis related disorders
Hallucinogen related disorders
Inhalant related disorders
Opioid related disorders
Sedative, hypnotic, anxiolytic related disorders
Stimulant related disorders
Tobacco related disorders
Other (or unknown) related disorders
Three stage cycle
- Binge/intoxication with a substance
- Withdrawal/negative affect
- Preoccupation/anticipation
Cycle increases in severity with continued substance use and produces
dramatic changes in brain function.
Reduced ability to control substance use
These changes in the brain persist long after substance use stops
in the binge intoxication stage, individuals typically consume an intoxicating substance and as a result of that experience, either a rewarding or pleasurable effects.
In the withdrawal or negative effect stage, individuals then experience a negative emotional state and the absence of that substance. Or I guess in the absence of funds to procure the substance
the final stage is the preoccupation or anticipation stage, which relates to the behaviors and activities that are required to seek a substance in a period of abstinence.
How does the brain change?
Main areas of brain involved:
Basal ganglia - pleasure and habitforming
Extended amygdala - stress and
negative feelings associated with
withdrawal
Prefrontal cortex - executive functionexerting control over substance use
Substance misuse disrupts the dopamine
circuits in the brain - both acutely and
chronically
Reduction in D2 receptors
Decrease in the sensitivity of the brain’s
reward system (to drugs as well as other
‘natural’ means of pleasure - food, sex)
basal ganglia is responsible for controlling both rewarding or pleasurable effects of a substance, and it’s also responsible for the formation of habitual substance. Taking
- triggers are what we would call reinforcers because the pleasurable feeling that we get from them kind of encourages us to continue or makes us more likely to engage in them again
- Within the basal ganglia, we have the nucleus accumbens, which is responsible for both motivation and experience of reward.
- dorsal striatum, which is then involved in forming habits and other routine behaviors.
extended amygdala, this is involved with feelings of stress, anxiety, and irritability, and this is what we typically associate with symptoms of withdrawal
prefrontal cortex. And this is involved in executive functioning, which includes exerting control over substance taking
Dopamine release in the brain over
time
this scan shows the loss of dopamine receptors that can occur over time. And this is in someone who has had several months of cocaine use. So the dopamine receptors are actually shown in red on the very far side of this image. And as you can see, after four months, we see very little red left in the scan. And so what this suggests is that fundamental brain changes explain why increasing quantities are required to seek that same initial effect
Behaviors of the cycle
a person may go through this three-stage cycle (binde, withdrawal, preoccupation) over the course of a couple of weeks or a couple of months. Or they could progress it through it several times in a day or even several times in an hour, depending on the specific substance. So there may be variation in how people progress through this cycle and the intensity in which they experience each stage. But nonetheless, this cycle tends to intensify over time for people, which then leads to greater physical and psychological harm.\
Impulsivity: initial substance use involves an element of impulsivity. And this can range from trying your first drink at a party to smoking a cigarette in-between classes, experimenting with cannabis or succumbing to peer pressure to try a party drug in any kind of different setting.
Pos rein: if this experience is pleasurable, this feeling positively reinforces their experience, have substance use and this makes them more likely to take the substance.
Neg rein: we may see people trying substances to relieve negative feelings. And this can be feeling such as stress, anxiety, or depression.t increases the chance that people will use again because they’re using in a way that it’s intended to relieve these negative feelings
Compulsivity: As use becomes more engrained, impulsivity moves to compulsive pattern. shifts from wanting to feel pleasure to needing to feel relief from the physical symptoms or the emotional symptoms in the absence of the substance We’re looking for a pattern of compulsive substance seeking, as well as a loss of control over this substance use. And these two traits are most commonly seen in people who are looking to feel relief
Risk factors
Early life experiences (abuse, neglect, poverty, etc.)
Exposure during adolescence
Genetic component (40-70%)
Environment/peer groups
Psychiatric comorbidity
Differences based on sex, race, and ethnicity
during adolescence, we’re undergoing significant brain changes during this stage, which makes us particularly vulnerable to substance exposure. And this includes substances that are more normalized in our society, including alcohol and cannabis. So our prefrontal frontal cortex isn’t actually fully developed until our mid-twenties. Research shows that heavy drinking and substance use during adolescents will affect the development of this critical brain area
the earlier your exposure to substances, the greater the risk is of developing a substance use disorder.
although there are multiple genes that are involved in this, only a few specific gene variants have been identified that either predisposed to or protect against substance use disorders. while most of these variants have been associated with how we metabolize certain substances, especially alcohol or nicotine, There may be other genes that are involved in either receptors, like generation of receptors are proteins that are associated with key neurotransmitters that are involved in that addiction cycle
genes that are involved in strengthening the connections between neurons and that are responsible for forming our drug memories are what is associated with potentially the risk of developing an addiction
Psychiatric comorbidity
Substance related disorders are twice as common in the psychiatric
population versus the non-psychiatric population
Psychiatric disorders are twice as common in the substance
disorders population versus non substance-using population
Support for overlapping commonality (“concurrent disorder”):
- Genetic vulnerabilities
–>Early exposure to substances, developmental changes in the brain
- Environmental triggers
–>Stress, trauma
-Similar brain regions/chemicals
–>Dopamine, GABA
Psychiatric comorbidity is associated with poorer treatment
outcomes, more severe illness course, and high healthcare/service
utilization in hospital and community
Very common: antisocial personality disorder (84%), schizophrenia
(47%)
Less common, but significant: affective disorders (depression,
bipolar) (32%), anxiety disorders (24%
The Brain Story
bain architecture and devleopment
Emphasis on how critical the first 0-6 years are
Inadequate experiences and negative environments lead to
development of toxic stress
- Affects gene expression responsible for regulating stress
- Long lasting changes in behavior and health
- Exaggerated neurological response to toxic stress never goes away
–>Mental health concerns, behavioral issues, and predisposition to
addiction as coping mechanism
Tolerable stress = if we have supportive people in our lives who are around to buffer a stress response when were a kid, these situations won’t do lasting damage to our brains and our coping mechanisms
Toxic stress: typically occurs when there are no supports or caregivers around to buffer a child’s response to repeated negative experiences. There’s a range of things that can cause toxic stress, including abuse, neglect. Parents who have substance use disorders are parents who have psychiatric disorders experiencing violence both in or outside of our homes
Adverse Childhood Experiences
(ACEs)
defn
Abuse
- Emotional
- Physical
- Sexual
Household dysfunction
- Domestic violence
- Household substance use
- Mental or chronic physical illness in the household
- Parental separation or divorce
Also: emotional and physical neglect, incarceration of caregiver or parent
↑ ACEs = ↑ risk for:
Alcoholism and alcohol abuse
Depression/anxiety, suicide attempts
Illicit drug use
STIs, multiple sexual partners, early initiation of sexual activity
Fetal death, unintended pregnancies
Poor work performance, poor academic achievement
Financial stress
Poor health-related QOL
Ischemic heart disease
COPD
Liver disease
Intimate partner violence, sexual violence
How do we know this?
Population-based studies
Objective: examine associations between childhood trauma and adult health outcomes
Landmark study (1995-1997)
United States
In partnership with the Centres for Disease Control and Prevention
17,000 participants
Alberta study (2015)
1207 participants
Adult health outcomes
physical health
High blood pressure
Diabetes
IBS/Crohn’s
Chronic pain
Back pain
Asthma
Allergies
Chronic fatigue/fibromyalgia
mental health
- anxiety
- depression
- other
substance use
