Crossing the line: When does teen substance use become abuse or dependence?
Many adolescents are ‘diagnostic orphans,’ whose behavior falls short of DSM-IV criteria but clearly shows substance use patterns.
Assessing an adolescent for a possible substance use disorder can be streamlined by choosing age-appropriate screening tools and asking targeted questions. Based on our experience, we offer a 4-step approach to these at-risk patients1 (Box) that focuses on:
- quantifying alcohol or drug abuse and/or dependence
- identifying and treating psychiatric comorbidity
- evaluating and addressing social influences that contribute to substance use
- assessing negative consequences associated with substance abuse.
Portrait of adolescent substance abuse
Adolescent substance use increases the risk of motor vehicle accidents, suicide, transmission of HIV and other sexual diseases, criminal behaviors, and psychological problems. Alcohol and marijuana are the substances most commonly abused by adolescents.
In 2002, the University of Michigan Institute for Social Research’s annual “Monitoring the Future” study reported:
- drunkenness in 7% of 8th graders, 18% of 10th graders, and 30% of 12th graders at least once in the previous 30 days.
- illicit drug use by 18% of 8th graders, 35% of 10th graders, and 41% of 12th graders in the previous 12 months.
Boys used substances more frequently than girls, and boys’ use was more severe. Within the previous month, boys reported greater alcohol use, binge drinking (five or more drinks in one sitting), and heavy drinking, as well as greater illicit drug use in the past year.1
Adolescents generally do not seek substance abuse treatment but are referred because of alcohol- or drug-related legal, school, or family problems. Thus, most present for evaluation with their parents, legal guardians, or officers of the court.
We begin by finding out from parents or guardians the reasons for the evaluation, their perspectives on the adolescent’s behavior, and their expectations of treatment. Then we interview the adolescent alone, assessing for substance use and evaluating peer relationships.
Components. A typical initial evaluation takes 90 minutes to 2 hours and includes:
- psychiatric history and symptoms
- medical history
- previous hospitalizations (medical and psychiatric)
- family history
- social history.
Specifically, the assessment focuses on the reason for the evaluation, with attention to diagnostic criteria for substance use/dependence.
STEP 1: QUANTIFYING DEPENDENCE
As with adults, clinical diagnosis of substance abuse or dependence in adolescents is based on DSM-IV diagnostic criteria (Table 1). Adolescents, however, differ from adults in diagnostic presentation, risk of dependence, and patterns of substance use.
Diagnostic ‘orphans.’ DSM-IV criteria for alcohol use disorders have limitations in adolescents.2 Teens who report one or two dependence symptoms and no abuse symptoms have been described as “diagnostic orphans”3—they fall short of criteria for dependence or abuse but clearly demonstrate substance use patterns. This presentation is common; in a survey of 74,008 high school students, almost 10% of 12th graders reported one or two dependence symptoms and no abuse symptoms.4
Risk of dependence. Adolescents who begin using alcohol or drugs develop dependence more rapidly than adults do.5
Patterns of use. Adolescents are more likely than adults to binge with alcohol and drugs, which may conceal the severity of their abuse. DSM-IV diagnostic criteria for substance abuse or dependence do not consider quantity of use, such as number of drinks or percent of days drinking or using drugs.
Assessment instruments. Many assessment instruments are available to explore adolescent substance use and its associated consequences. Some are described in detail and are available on the Internet. Common screening instruments that can be used for adolescent substance use are compared in Table 2.
DUSI-A and POSIT. Two self-report instruments—Drug Use Screening Inventory-Adolescents (DUSI-A)6 and Problem Oriented Screening Instrument for Teenagers (POSIT)7—can help explore alcohol or drug use in teens who admit to substance use. Anyone who endorses at least one DSM-IV abuse or dependence criterion requires further evaluation. Either test is a good starting point, and both have a built-in “lie” scale.
T-ASI and CASI. The Teen Addiction Severity Index (T-ASI)8 and Comprehensive Adolescent Severity Inventory (CASI)9 are more labor-intensive and require training to administer. These assessments are more appropriate for adolescents with extensive alcohol or drug abuse.
These self-report instruments have been validated in treatment- and nontreatment-seeking adolescents and young adults in inpatient and outpatient populations. They are sensitive and specific in identifying problem drinkers and marijuana users, respectively, and are quick, useful screens to determine need for further assessment.
Toxicology is useful for initial assessment and to monitor substance use patterns during treatment.
Urine samples are used to assess marijuana, sedative/hypnotic, amphetamine, cocaine, opiate, and phencyclidine use. Alcohol may be detected in urine, but alcohol levels detected by blood and breath testing are more accurate.
Diagnostic criteria for substance abuse and dependence
1 of these 4 symptoms in a 12-month period: Role impairment
At least 3 of the following: Tolerance
Marijuana may be detected in the urine for 3 days to 4 weeks, depending on level of use. Cocaine can be detected for 2 to 4 days in urine and longer in hair analysis.
Random screening. Adolescents who use drugs usually know how long substances can be detected, so random urine drug screening is important to treatment progress. We inform adolescents at the beginning of treatment that random screening will be performed to corroborate self-report of substance use. To ensure a reliable urine sample, same-gender staff observe while the adolescent gives the sample.
Common screening instruments for alcohol and drug use in adolescents
Drug Use Screening Inventory (DUSI-R), Revised
20 to 40 minutes
Problem-Oriented Screening Instrument for Teenagers (POSIT)
20 to 30 minutes
Teen Addiction Severity Index (T-ASI)
20 to 45 minutes
Comprehensive Adolescent Severity Inventory (CASI)
Varies with experience of administrator
Adolescent Obsessive-Compulsive Drinking Scale (A-OCDS)
About 5 minutes
Deas-Marijuana Obsessive-Compulsive Scale (Deas-MOCS)
About 5 minutes
STEP 2: IDENTIFYING PSYCHIATRIC COMORBIDITY
In adolescents, substance use disorder frequently goes hand-in-hand with psychiatric disorders, particularly:
- mood and anxiety disorders
- disruptive disorders (attention-deficit/hyperactivity, oppositional defiant, and conduct disorders)12
- and posttraumatic stress disorder.13
Uncontrolled psychiatric disorders may sabotage substance abuse treatment. Therefore, assess any adolescent presenting with substance use for psychiatric illness.
Did psychiatric symptoms predate or postdate substance use? The answer may suggest self-medication or a substance-induced phenomenon. This assumption does not always apply, however, as many factors affect the relationship between substance use and psychiatric disorders.
Adolescents who meet DSM-IV criteria for conduct disorder—especially those who are highly aggressive—tend to initiate substance use much earlier than adolescents without conduct disorder, and they continue their use longer.
Most adolescents with comorbid psychiatric and substance use disorders develop the psychiatric disorder first. Some report using various substances to medicate their psychiatric symptoms. Early diagnosis and treatment of the psychiatric disorder may prevent or decrease the adolescent’s substance use.
STEPS 3 AND 4: EVALUATING SOCIAL INFLUENCES AND CONSEQUENCES
Social influences that contribute to adolescent alcohol and drug abuse include family dynamics and peer relationships. Consequences include educational and legal problems. We explore these areas with the adolescents and their parents/guardians. In most cases, adolescents are honest when reporting how their alcohol or drug use has affected their lives.
What is his family like? Assess the adolescent’s family, including its structure and history of substance abuse, psychiatric illness, or trauma (Table 3). Adolescents whose parents or siblings use alcohol or drugs are at increased risk for substance use.14 To what extent this association is genetic, environmental, or both is undetermined, but the genetic influence increases as adolescents age.15
Who are her friends? Adolescents who try alcohol or drugs and continue to use them tend to have peers who use these substances. 16 Moreover, the severity of adolescents’ substance use is correlated with the number of substance-using peers. To explore peer relationships, ask about:
- peer group composition, including whether peers use alcohol or drugs
- peer interactions, including the adolescent’s ability to assert him- or herself in the peer group
- markers for risky sexual behaviors related to substance use, including infection with HIV and other sexually transmitted diseases.
How is she doing in school? Inquire about the teen’s academic performance, attendance, disciplinary problems, and motivation. Even a small decline in school performance or an increase in disciplinary problems that result in suspension or expulsion can indicate substance use or other at-risk behaviors.
Poor grades or attendance problems suggest but are not the only clues to substance use. Some adolescents with good school performance engage in substance use and may be impaired in other life domains.
Has he been arrested? Substance-abusing adolescents tend to engage in delinquent behaviors, including shoplifting, vandalism, curfew violations, disorderly conduct, and drunken driving. When assessing for delinquency, ask about behaviors that did or did not result in arrest. The teen who avoided arrest for illegal activities may perceive his/her behaviors as less severe than those involving arrest, and it may help to address this denial in individual or group therapy.
Questions to assess family influence on an adolescent’s substance use
We consider any adolescent with dependence symptoms—whether or not the presentation meets full DSM-IV diagnostic criteria—to be a candidate for further assessment and treatment. Early intervention may prevent progression to substance dependence.
- are intensive and of sufficient duration to change attitude and behaviors
- are comprehensive and target multiple domains of the adolescent’s life
- are sensitive to cultural and socioeconomic realities
- involve the family
- emphasize pro-social recreational activities, such as playing sports, attending movies, camping, having lunch or dinner with peers, etc.
Inpatient or outpatient? Managed care and insurance restrictions limit many patients’ eligibility for inpatient or residential treatment, so partial hospitalization and outpatient settings have become standard for substance abuse treatment. Partial hospitalization programs vary but may entail several hours, several days per week. Outpatient treatment may encompass individual, group, and family therapy, including after-school programs.
Inpatient treatment is usually reserved for adolescents:
- who need detoxification
- with comorbid psychiatric disorders
- or who may harm themselves or others.
Behavioral therapy, family-based therapy, multisystematic therapy (MST), and 12-step approaches have shown efficacy in treating adolescents with substance use disorders.
Behavioral therapy. Behavioral therapy is recommended as initial treatment because substance use plays a functional role in the adolescent’s life and is learned and reinforced in the adolescent’s environment. Homework assignments and role-play are commonly used in therapy.
Three central ingredients are:
- functional analysis (identifying internal and external triggers for starting and continuing substance use)
- skills training (targeting problems identified in the functional analysis)
- and relapse prevention.
Behavioral therapy is more effective than supportive therapy in improving family relationships and school and work attendance and in decreasing substance use, as indicated by fewer positive urine toxicology screens.17
Cognitive-behavioral therapy (CBT) approaches substance use as a maladaptive response to life problems. Its goal is to teach new skills to help the adolescent recognize and avoid high-risk situations and cope with associated problems and behaviors.