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Understanding Substance Use Disorders. Jean J. Bonhomme M.D., M.P.H. Assistant Professor, Morehouse School of Medicine Department of Psychiatry jbonhomme@msm.edu. Role of the Pediatrician. Most substance use disorders actually begin in the pediatric age group.
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Understanding Substance Use Disorders Jean J. Bonhomme M.D., M.P.H. Assistant Professor, Morehouse School of Medicine Department of Psychiatry jbonhomme@msm.edu
Role of the Pediatrician • Most substance use disorders actually begin in the pediatric age group. • Few people start smoking after age 26. • Cigarette and liquor advertising targets young people • Peer group pressure to use is common. • The teenager who can “really hold their liquor” is most at risk of alcoholism. • Family history is an important risk factor.
The CDC's Best Practices for Comprehensive Tobacco Control Programs (1999) • Most people begin using tobacco in early adolescence, typically by age 16; • Children buy the most heavily advertised brands, and are three times more affected by advertising than adults. • Smoking prevalence is higher among adults living below the poverty level (32.3 percent) than for those living at or above the poverty level (23.5 percent). • (Source: Oral Cancer Foundation)
Morehouse School of Medicine • Morehouse Presidents David Satcher, Louis Sullivan, and James Gavin (2004): • Tobacco companies actively target minority youth using: • Tobacco ads and products placed at children’s eye level in retail outlets • Fruit flavored tobacco products • Hip-hop packaging
Cultural factors impacting this group • Include family, media and community role models; • Social acceptability of tobacco; • Tobacco as a gateway drug; • Image (looking grown up, sexy);; • Tobacco as a vehicle for other drugs (marijuana, crack, etc.); and • Tobacco as self medication / stress relief.
Morehouse Presidents • Called for the tobacco companies to remove these products from the shelves. • Tobacco companies refused, stating that they had met the terms of the tobacco settlement. • There is a pressing need for effective policy and informational countermeasures targeting this vulnerable population to promote tobacco avoidance and to encourage tobacco cessation.
Signs of Drug use by Children • Direct drug effects and signs on P.E., e.g. abnormal pupil size or needle marks, red eves, weight loss • Unexplained increase in truancy and / or lateness to classes • Sudden decrease in academic performance • New onset behavioral problems in schoolLoss if interest in previously enjoyed activities • Hanging out in a new crowd and dropping old friends • Personality changes, e.g. new onset social withdrawal, becoming fidgety or listless
Signs of Drug use by Children • Sudden unexplained mood changes, e.g. depression, edginess, suspiciousness or paranoia • Memory problems • Increased secretiveness and withdrawal from family • Increased combativeness • Sleep problems, fatigue or hyperactivity • Higher index of suspicion if a positive family history of alcoholism or addiction is noted
Addiction vs. Dependence: an important new distinction Source: Principles of Addiction Medicine, 3rd Edition American Society of Addiction Medicine
Addiction Defined • Addiction is defined as continued substance use in the face of adverse consequences. • Extreme compulsion is the overriding feature. • Examples - Using drugs and/or alcohol to the point of intoxication and grossly impaired function, e.g. a person gets arrested for drunken driving and their license is confiscated. • Two days later they are on the road again and drunk. Punishment appears to be no deterrent. • Key: In the presence of the substance, function deteriorates, but use continues.
Dependence Defined • Dependence is very different - defined as a state in which the body relies on a substance for normal functioning. • Example: A person has a ruptured disk in the lower back, with pain is so severe that they cannot work or take care of their children. • When they are given an opiate pain medication, the pain is reduced to the point where they can function normally and responsibly. • Key: In the presence of the substance, function normalizes.
What is the Importance of This Distinction? • DSM-IV does not make any distinction here. • Usually neither do the criminal courts. • In both instances, the person really needs the substance, but the consequences of their use are completely different. • Not making this distinction lumps persons with a legitimate need for a controlled substance together with those who are actively misusing them. • A crucial distinction: between people who are being helped and those who are harming themselves and others by their drug use. • Example – Sickle Cell patient in ER.
The Anatomy Underlying This Distinction • Addiction is clearly a brain disease. • Different parts of the brain are responsible for addiction (versus dependence) to opiates. • The areas in the brain underlying addiction to morphine are the reward pathway (including the VTA, nucleus accumbens, and prefrontal cortex). • All drugs of addiction appear to involve the reward pathway. • Those areas underlying dependence to morphine are the thalamus and brainstem.
Dependence Explained • It is possible to be dependent without being addicted, a very important distinction. • This is especially true for people being treated chronically with opiates, e.g. pain associated with terminal cancer. • They may be dependent - if the drug is stopped, they suffer recurrence of pain and a withdrawal syndrome. However, they are not compulsive users. • However, if one is addicted, they are most likely dependent as well.
Dependence Explained • Not every dependent person is an addict, not even those who need very high doses of medication. • Most people treated with opiates are unlikely to become addicted, for example in a hospital setting for pain control after surgery. • Although they may feel some euphoria although pain relief and sedating effects predominate. • There is no pattern of compulsive use and the prescribed use is short-lived.
Why Did DSM-IV Fail to Make This Distinction? • There was some debate as to whether compulsive substance use leading to adverse consequences should be called “addiction” or “dependence.” • It was felt by some that the term “addiction” was too pejorative and prejudicial, such that persons with a diagnosis of addiction would be very harshly judged. • The term “dependence” was felt to be much less prejudicial, so by one vote, it was decided to use the term “dependence.” • This has led to much confusion. Plans exist currently to change terminology for DSM-V.
So How Do We Define Substance Abuse? • In drug abuse, function may deteriorate in the presence of the drug and other adverse consequences may ensue, but there is no compulsion to continue using the drug. • Example: A person uses a drug for recreational purposes for some time, then has a bad experience, such as an overdose or a brush with the law. They say “That’s it – I’m through with this stuff.” • This is not addiction, because they voluntarily left it alone when it clearly became more trouble than it’s worth. • A true addict cannot do this.
Tolerance Explained • Tolerance is defined as progressively decreasing response to a drug with exposure. Increased doses are necessary to get the same effect. • This usually refers to repeated or prolonged exposure, which is called chronic tolerance. • Rarely, sensitivity to a drug may increase with repeated exposure, called reverse tolerance. • Having high tolerance and needing high doses of a drug is NOT addiction.
Mechanisms of Tolerance • Metabolic • Due to stimulation of the enzymes that break down the drug. • Adaptive • The body adapts to the presence of the drug – this is characteristic of most drugs that lead to use disorders. • The drug must be taken in increasing quantities to achieve the same effect.
The Withdrawal Syndrome Explained • Withdrawal is a group of negative physical and mental effects resulting from discontinuation of addictive substances by persons who have become habituated to their use. • Withdrawal symptoms may include severe drug cravings as well as a group of negative physical symptoms that may occur when a person suddenly stops using a drug to which he or she has become dependent. • Generally, the longer the drugs are taken and the higher the dose, the more severe the symptoms.
The Withdrawal Syndrome Does NOT Equal Addiction • If you give adequate doses of opiates to a person in opiate withdrawal, often they can resume normal function. • After being gradually tapered off, most people do not go back to using. • By contrast, truly addicted people who have been incarcerated for years and are long past any remnant of the physical withdrawal syndrome may relapse on drugs within months, weeks, days or even hours of their release.
Route of Drug Administration and Risk of Addiction • Smoking is actually potentially the most addictive route of drug administration. • Behavioral science has proven that the faster a reward or punishment follows an action, the greater the impact of that reward or punishment on future behavior. • When a drug is snorted, it takes 30 to 120 seconds to get into the blood, and high blood levels of the drug are rarely attained.
Example: Cocaine • Snorting requires that the cocaine travels from the blood vessels in the nose to the heart (blue vessels), where it gets pumped to the lungs (blue vessels) to be oxygenated. • The oxygenated blood (red vessels) carrying the cocaine then travels back to the heart where it is pumped out to the organs of the body (red vessels), including the brain.
Route of Administration and Addiction Potential • When a drug is injected in the arm, it takes a long circulatory pathway, up the arm, into the right side of the heart, into the lungs, into the left side of the heart, and into the carotid arteries to the brain. • High blood levels of the drug are commonly attained. • This process takes about eighteen seconds.
Example: Cocaine • Smoking cocaine: high addictive liability • Historically cocaine abuse involved snorting or injecting the powdered form (the hydrochloride salt). • When cocaine is processed to form the freebase, like crack, it can be smoked. • Heating the hydrochloride salt form of cocaine will destroy it; the freebase can be vaporized at high temperature without any destruction of the compound, leading to much quicker onset of action.
Route of Administration and Addiction Potential • When a drug is smoked, it takes a short circulatory path, into the lungs, into the left side of the heart, and into the carotid arteries to the brain. • Because of the enormous surface area of the lungs (roughly the area of a tennis court), high blood levels of the drug are commonly attained, as is the case with injection. • This process takes only about seven seconds.
Route of Administration and Addiction Potential • If you were training a dog with food rewards, which would be most effective in getting the animal to repeat the rewarded behavior – giving the food in seven seconds, in eighteen seconds, or in 30-120 seconds? • Rapidity of onset of action is strongly associated with addictive potential. • Consider how hard it is to give up cigarettes, or how explosively cocaine addiction grew when the smokeable crack form was introduced.
Route of Administration and Needle Aversion • This is the opposite of what you would think because solids seem more substantial than liquids, and liquids seem more substantial than vapors. However, vapors can actually get into the brain the most quickly. • Perhaps worst of all, smoking is much more socially acceptable behavior than using needles or snorting due to our long history of accepting tobacco smoking. • For this reason, when a drug is presented in smokeable form, a major social barrier to beginning its use (called needle aversion) is removed.
Pharmacological Half-Life and Addiction • Half-life is the time it takes for the body to eliminate half of the drug from the blood. • Drugs with shorter half-lives tend to have greater addictive potential than drugs with longer half lives because shorter duration of action causes a need to take more often. • Behavioral science tells us that the more often a behavior is practiced, the greater the tendency to become habitual. • e.g. crack cocaine – must be taken every few minutes, increases addictive potential.
Pharmacological Half-Life and Addiction • Methadone treatment, which only needs to be taken once daily to suppress withdrawal is much less likely to promote constant drug seeking behavior than oxy-contin or heroin, which must be taken several times daily to maintain adequate blood levels. • People addicted to heroin are practicing drug seeking / using behavior several times a day, every day, day and night. • People on methadone take one dose in the morning and go about their business for the rest of the day.
Neurotransmitters 101 The Basics
Why Discuss Neurotransmitters? • They are natural chemical messengers. • Nerve cells communicate with each other by sending these chemicals across gaps between cells, called synapses. • Psychoactive drugs create their effects by modifying the actions of neurotransmitters: • Increasing, • Decreasing, • Blocking, • Mimicking, or • Otherwise modifying them
Key Neurotransmitter Functions • Acetylcholine (Ach): thought, movement • Dopamine (DA): pleasure, motion • Serotonin: relaxation, mood • Glutamate: the brain’s accelerator pedal • Gamma-amino-butryic acid (GABA): the brain’s brake pedal • Endorphins (Enkephalins, Dynorphins): the brain’s natural painkillers
So With Neurotransmitters, How Does Addiction Work? • By altering neurotransmitter actions, sometimes in complex ways, addictive drugs hijack the brain’s reward system. • The same areas of the brain that govern our natural drives for food, water and sex get taken over completely by the drug. • Often, addicts will reach a point where they can no longer derive pleasure from natural means anymore. • They may derive pleasure only from the drug, and then eventually end up using the drug not even feeling pleasure anymore, but just to feel reasonably normal.
Demographics Who Is Using All These Drugs?
The Demographics of Substance Use Disorders • The National Survey on Drug Use and Health • http://www.oas.samhsa.gov/nhsda.htm • An annual survey conducted by the Substance Abuse and Mental Health Services Administration (SAMHSA) • Estimates the prevalence of illicit drug use in the United States. • Some of the more notable statistics from the 2004 study follow.
Alcohol vs. Drugs • In 2004, about 22.5 million Americans aged > or = 12 reported past year substance abuse or dependence (9.4% of the population). • Of these, 3.4 million were dependent on or abused both alcohol and illicit drugs. • 3.9 million were dependent on or abused illicit drugs but not alcohol, and • 15.2 million were dependent on or abused alcohol but not illicit drugs. • 19.1 million Americans were current substance users (used at least once during the 30 days prior to the interview.)
Cocaine, Hallucinogens, MDMA and Marijuana Use • There were 2.0 million current cocaine users, 467,000 of whom used crack. • Hallucinogens were used by 929,000 people • There were an estimated 166,000 heroin users. • There were an estimated 450,000 Ecstasy (MDMA) users. • Marijuana is the most commonly used illicit drug, with a rate of 6.1% of the population (14.6 million current users).
Nonmedical Use of Psychotherapeutic Medications • In 2004, 6.0 million persons were current users of painkillers or psychotherapeutic drugs taken nonmedically (2.5% of the population). • These include 4.4 million who used pain relievers, • 1.6 million who used tranquilizers, • 1.2 million who used stimulants, and • 0.3 million who used sedatives.
Employment Status and Drug Use • In 2004, 19.2% of unemployed adults aged 18 or older were current illicit drug users compared with: • 8.0% of those employed full time and • 10.3% of those employed part time. • However, of the 16.4 million illicit drug users aged 18 or older in 2004, “12.3 million (75.2%) were employed either full or part time.”
Ethnicity and Drug Use: Dispelling the Myths • In 2004, 7.9% of the population aged 12–17 years reported current illicit drug use . • Breakdown by racial/ethnic group: • 26.0% Native American / Alaskan youths • 12.2% for Biracial or Multiracial youths • 11.1% for White youths, • 10.2% for Latino youths, • 9.3% for African-American youths, • and 6.0% for Asian youths.
Mortality and Morbidity of Untreated Opiate Addiction • Untreated heroin addicts suffer a death rate thirteen times that of the general population. • More so today than ever, heroin is not the only opiate contributing to the landscape of addiction. • Excess deaths and illnesses occur from a wide variety of causes, including but not limited to: • Drug effects, overdoses and interactions, • Intentional and unintentional injuries • Infectious diseases.
The economic costs of heroin addiction in the United States • Mark T L; Woody et al (2001) • We estimate that the cost of heroin addiction in the United States was $21.9 billion in 1996. • Of these costs, productivity losses accounted for $11.5 billion (53%), criminal activities $5.2 billion (24%), medical care $5.0 billion (23%), and social welfare $0.1 billion (0.5%). • This economic burden highlights the importance of investment in prevention and treatment.
Is the Problem of Opiate Addiction Likely to Increase? • Increasing purity of heroin has been reported in the Southeastern U.S. – up to 70% pure on the streets of Atlanta. Purity is catching up with the Northeastern U.S. • Increasing availability of Pharmaceutical opiates – 12 year olds have ordered Oxy-contin from offshore sites via internet. • Newer opiates – Oxy-Contin, Fentanyl, etc. • Effective non-injection delivery systems – smoking, snorting, eating the contents of fentanyl patches.
Ethnicity and Differential Sentencing for Drug Possession • Differential sentencing for drug possession based on the form of drug commonly used by specific ethnic groups has dramatically increased the proportion of incarcerated ethnic minorities (Braithwaite & Arriola, 2009). • African Americans and Latinos tend to use cocaine in “crack” form rather than as powder. • However, crack is simply cocaine powder processed by cooking with common baking soda (making a “crackling” sound, hence the name), but possession of crack typically incurs a much harsher sentence.