Chapter 36. Oppositional Defiant Disorder and Conduct Disorder

Essentials of Diagnosis

DSM-IV-TR Diagnostic Criteria

1. A pattern of negative, hostile, and defiant behavior lasting at least 6 months, during which four (or more) of the following are present:

   1. often loses temper

   2. often argues with adults

   3. often actively defies or refuses to comply with adults’ requests or rules

   4. often deliberately annoys people

   5. often blames others for his or her mistakes or misbehavior

   6. is often touchy or easily annoyed by others

   7. is often angry or resentful

   8. is often spiteful or vindictive

   • Note: Consider a criterion met only if the behavior occurs more frequently than is typically observed in individuals of comparable age and developmental level.

2. The disturbance in behavior causes clinically significant impairment in social, academic, or occupational functioning.

3. The behaviors do not occur exclusively during the course of psychotic or mood disorder.

4. Criteria are not met for conduct disorder, and, if the individual is 18 years or older, criteria are not met for antisocial personality disorder.

(Reprinted, with permission, from Diagnostic and Statistical Manual of Mental Disorders, 4th edn., Text Revision. Copyright 2000 American Psychiatric Association.)

General Considerations

As with conduct disorder and attention-deficit/hyperactivity disorder (ADHD) (described in previous chapter), with which it is often entangled, it is uncertain whether oppositional defiant disorder is a truly distinctive nosological category. Specifically, it is unclear whether oppositional behavior is better considered to be on a continuum between normal developmental limit-testing on the one hand and pathologically disruptive behavior on the other. The distinction between categorical disorders and dimensional psychopathology is more than a theoretical quibble. Valid categories delimit disorders that are likely to have a significantly biological (e.g., neurochemical) basis. Dimensional sets of behavior masquerading as categories may, in fact, obscure true categories that nest within their fictitious boundaries.

Oppositional defiant disorder, as defined in DSM-IV-TR, is manifest as age-inappropriate, persistent, intemperate, argumentative, defiant, deliberately annoying, irritable, resentful, vindictive behavior associated with the tendency of the subject to blame others for his or her own transgressions or omissions. The aggression of the oppositional child or adolescent is predominantly verbal rather than physical. The aggression tends to be reactive (e.g., in response to an unwelcome imposition of rules) rather than proactive (e.g., bullying), and overt (e.g., shouting) rather than covert (e.g., spreading malicious rumors).

Epidemiology

The prevalence of oppositional defiant disorder is uncertain, but it has been estimated at 5.7–9.9%. The average age at onset is 6 years. Oppositional defiant disorder is regarded by many researchers as a milder, precocious form of conduct disorder. The male-to-female sex ratio in childhood conduct disorder is 4:1. There is a clinical impression that childhood oppositional defiant disorder is more common among preadolescent males than females, however, the relative prevalence in females appears to rise in adolescence.

Etiology

The genesis of oppositional defiant disorder has not been studied separately from that of conduct disorder. Because conduct disorder often evolves from earlier oppositional behavior, and because the two disorders have similar risk factors, oppositional defiant disorder and conduct disorder are often discussed together.

Many young children who exhibit oppositional defiant behavior were, as infants, already temperamentally hyperreactive, irritable, difficult to soothe, and slow to adapt to new circumstances. Infants who exhibit disorganized attachment behavior are at risk of oppositional, disruptive behavior in middle childhood. Often the families of these children are highly stressed, as a result, for example, of marital discord, single parenthood, parental psychopathology, or socioeconomic disadvantage. Maternal depression may be particularly common. Preoccupied with their own problems, parents fail to provide these children with adequate praise and attention. When parents seek to set limits, they do so harshly and inconsistently. The children react defiantly, testing the limits, and the stage is set for repetitive cycles of escalating coerciveness, with shouting and mutual accusations, often terminated by harsh physical punishment or by the capitulation of one or other of the antagonists. Children's aggressiveness is associated with how aggressive their parents were at the same age. Often parents respond to their children in the manner (and even with the same words) that their parents responded to them. In summary, a lack of positive reinforcement for acceptable behavior is associated with negative attention for oppositional behavior and with inconsistent, unpredictable, harsh punishment. Table 36–1 lists the characteristics of a coercive interaction. These factors can be targeted for therapeutic intervention (see “Treatment” section later in this chapter).

Genetics

The genetics of oppositional defiant disorder has not been studied apart from that of conduct disorder. Behavioral genetic studies of aggressive behavior in children have yielded inconsistent estimates of its heritability, probably because of variations in the measurement instruments used. Most studies suggest that the trait of aggressiveness has low heritability.

Clinical Findings

Signs and Symptoms

The persistent, recurrent aggressive and defiant behavior associated with oppositional defiant disorder may be restricted to the home or may be generalized as an antiauthoritarian attitude, for example, to teachers and other adults outside the home. It is usually evident before 8 years of age but may emerge for the first time in adolescence. Oppositional, hostile, limit-testing behavior disrupts family relationships and can interfere with learning. At school, oppositional children or adolescents may be moody, irritable, lacking in self-esteem, and often in conflict with teachers and peers. As a result, the oppositional child or adolescent often appears to have a “chip on his or her shoulder.” Oppositional adolescents may be solitary or inclined to gravitate to the company of others who regard themselves as outlaws. Precocious tobacco use is likely, as is alcohol and substance abuse.

Psychological Testing

Aside from questionnaires that are useful for assessing aggressive behavior (e.g., the Child Behavior Checklist and the Eyberg Child Behavior Inventory), a number of behavioral observation rating scales and questionnaires have been developed for the assessment of conflictual parent–child or family behavior (Table 36–2). These tests may be useful as monitors of the progress and effectiveness of treatment, in accordance with treatment goals and objectives.

Differential Diagnosis (Including Comorbid Conditions)

Oppositional defiant disorder should be differentiated from normal developmental limit-testing in toddlers and preschool children, and from the challenging confrontations that occur between parents and normal adolescents who are seeking to be more independent. Developmental oppositional behavior is transitory and causes no significant impairment.

Oppositional defiant disorder should be discriminated from ADHD, with which it frequently coexists, and from conduct disorder, which often succeeds it. An underlying mood disorder may be manifest, to the superficial observer, as sullen defiance. Premorbid schizophrenia or early schizophrenia is sometimes associated with negativism and marked contrasuggestibility. A comprehensive history and mental status examination will differentiate these two disorders.

Children with mental retardation, hearing loss, or impaired language comprehension are sometimes oppositional and defiant at school. Selective mutism often has oppositional features.

Oppositional defiant behavior often coexists with the following situations or conditions: Parental conflict, parental psychopathology (especially depression), physical or sexual abuse, conduct disorder, ADHD, and adolescent substance use disorder. In regard to the comorbidity of oppositional defiant disorder with ADHD and conduct disorder, it is unclear whether these disorders have mixed symptoms, whether they share risk factors, whether oppositional defiant disorder is a risk factor for other disorders, or whether it is an early manifestation of conduct disorder.

Treatment

Children

With children under 12 years of age, treatment is provided primarily through the parents. Whether as single parents, as parental dyads, or in parental groups, parents are educated concerning the origin and meaning of oppositional defiant behavior and are trained to replace coercive discipline with more effective child-rearing techniques. Table 36–3 describes the essentials of effective parenting.

The Positive Parenting Program (Triple P) contains all these elements and has been designed as a population-based intervention strategy. Triple P is a parenting and family support program that can be delivered in five levels: level 1 targets common, everyday behavior problems; level 2 targets oppositional defiant disorder; and levels 3–5 target severe behavior problems complicated by severe family psychopathology. The program can be delivered through parent information nights; through videotapes; by information and skills training delivered through individual, self-directed, and group programs; and through three levels of intensive family therapy (requiring specific training for the clinicians who implement the therapy). Table 36–4 lists the principles and objectives of the Triple P program.

Adolescents

In adolescent oppositional defiant disorder, a family therapy approach has had the most success. In the Problem Solving Communication Training (PSCT) program, the family is first assessed with regard to the issues described in Table 36–5. These issues can be described as molecular (i.e., family communication problems and poor problem solving) or molar (i.e., family structural and functional problems). Molecular issues provide the specific goals and objectives of therapy, whereas molar issues inform its strategy and tactics.

The treatment objectives of PSCT are listed in Table 36–5. Family communication and problem solving are addressed by eliciting the common causes of family disagreement and then ranking them in order of seriousness or difficulty. The family is directed to address one cause of dispute per session, starting with the least acrimonious, by using a formula for problem solution (Table 36–6). As the family addresses these problems, family communication pathology can be remediated with the use of feedback, instruction, modeling, and behavioral rehearsal. Sometimes, the family's communication patterns are so adverse that they must be addressed before PSCT can begin.

In the course of treatment, the family's rigid, biased beliefs will be revealed and targeted for cognitive restructuring (Table 36–7). In cognitive restructuring, the therapist challenges each dysfunctional belief, suggests a more reasonable alternative, and helps the family to conduct an “experiment” that will disconfirm the belief.

In a severely dysfunctional family system, PSCT and cognitive restructuring are unlikely to be effective unless the family's functional and structural pathology can also be addressed. PCST can be undermined by family members who are not involved in therapy or by outside agencies that oppose it. Severe psychopathology in a family member (e.g., maternal depression, paternal alcoholism, adolescent substance abuse) may need treatment before PSCT can proceed. A minimal level of verbal ability in family members is required for PSCT to be successful. PSCT by itself is unlikely to be effective if the adolescent patient has conduct disorder.

Prognosis

Oppositional defiant disorder is predicted by the same risk factors as is conduct disorder (e.g., marital discord, socioeconomic stress, maternal depression) but to a lesser degree. Although about 90% of children and adolescents with conduct disorder have previously met (and still meet) criteria for oppositional defiant disorder, only about 25% of children with oppositional defiant disorder go on to exhibit conduct disorder. About 50% continue to exhibit oppositional defiant disorder in late childhood and adolescence; and the remaining 25%, when assessed later, cease to meet criteria for either oppositional defiant disorder or conduct disorder.

The significance of these findings has been debated. Should oppositional defiant disorder be regarded as a precocious (albeit milder) form of conduct disorder? Or is it an extreme form of (and continuous with) normal oppositional behavior? What determines the developmental trajectory of the individual child? It has been postulated that one developmental trajectory proceeds from early oppositional-defiant behavior, along an authority conflict pathway, to serious conflict with adults during adolescence. This pathway is likely to intersect with the covert or overt antisocial trajectories described in the next section.

Oppositional behavior is common during adolescence. As described earlier in this chapter, when such behavior is severe, it is usually a manifestation of family dysfunction. The association between childhood oppositional defiant disorder and adolescent oppositional defiant disorder is unknown.

Essentials of Diagnosis

DSM-IV-TR Diagnostic Criteria

1. A repetitive and persistent pattern of behavior in which the basic rights of others or major age-appropriate societal norms or rules are violated, as manifested by the presence of three (or more) of the following criteria in the past 12 months, with at least one criterion present in the past 6 months:

   • Aggression to people and animals

     1. often bullies, threatens, or intimidates others

     2. often initiates physical fights

     3. has used a weapon that can cause serious physical harm to others

     4. has been physically cruel to people

     5. has been physically cruel to animals

     6. has stolen while confronting a victim

     7. has forced someone into sexual activity

   • Destruction of property

     8. has deliberately engaged in fire setting with the intention of causing serious damage

     9. has deliberately destroyed others’ property (other than by fire setting)

   • Deceitfulness or theft

     10. has broken into someone else's house, building, or car

     11. often lies to obtain goods or favors or to avoid obligations

     12. has stolen items of nontrivial value without confronting a victim

   • Serious violations of rules

     13. often stays out at night despite parental prohibitions, beginning before 13 years of age

     14. has run away from home overnight at least twice while living in parental or parental surrogate home (or once without returning for a lengthy period)

     15. often truant from school, beginning before age 13 years

2. The disturbance in behavior causes clinically significant impairment in social, academic, or occupational functioning.

3. If the individual is age 18 years or older, criteria are not met for antisocial personality disorder.

• Specify type based on age at onset: Childhood-onset type or adolescent-onset type.
• Specify severity: Mild, moderate, severe.

(Reprinted, with permission, from Diagnostic and Statistical Manual of Mental Disorders, 4th edn., Text Revision. Copyright 2000 Washington, DC: American Psychiatric Association.)

General Considerations

As described in DSM-IV-TR, the diagnostic features of conduct disorder have evolved from earlier multivariate factor analytic studies of child and adolescent clinical populations. A former division of delinquency syndromes into undersocialized aggression and socialized aggression has been dropped in favor of the atheoretical subcategories of childhood-onset and adolescent-onset types, either of which may be mild, moderate, or severe.

It has been difficult to disentangle the taxon of conduct disorder from several other behavior disorders with which it is frequently associated (e.g., oppositional defiant disorder, ADHD, and substance use disorder). Although conduct disorder is formally described as though it were categorically distinct, it almost certainly comprises a number of associated continua.

Conduct disorder must be distinguished from transient antisocial behavior that reflects the risk-taking and group contagion that are part of normal adolescence. Antisocial behavior is common in adolescence; in most cases it requires no psychiatric attention. Conduct disorder, in contrast, represents severe, persistent, and pervasive dysfunction.

Two types of aggression have been described, variously contrasted as reactive/proactive, overt/covert, affective/predatory, defensive/offensive, socialized/under-socialized, impulsive/controlled, or hostile/instrumental. Reactive, affective, impulsive aggression is likely to be associated with child maltreatment.

Epidemiology

Definitive conclusions about the prevalence of conduct disorder are difficult to reach because studies have differed in the geographic areas and age ranges studied and in the methods of assessment. However, it is evident that conduct disorder is one of the most common problems in childhood and adolescence. Overall prevalence rates for conduct disorder have varied from 0.9% (Germany) to 8.7% (Missouri). Prevalence rates in adolescents have varied from 9% to 10% in boys and from 3% to 4% in girls. The prevalence of antisocial personality disorder in adults is estimated to be 2.6%. Two studies found that African-American youths were more likely to be assigned the diagnosis of conduct disorder; however, comparative studies are few.

Prospective studies have identified the following individual variables as associated with later adjudications for delinquency: drug use, stealing, aggression, general problem behavior, truancy, poor educational achievement, and lying. The following environmental variables predict delinquency: poor parental supervision, lack of parental involvement, poor discipline, parental absence, poor parental health, low socioeconomic status, and association with deviant peers. The following factors are protective: high IQ, easy temperament, good social skills, good school achievement, and a good relationship with at least one adult. Composite behavioral indices have greater predictive power than do single variables, supporting a cumulative risk model. One model of transmission postulates a genetic propensity that is triggered if the subject is exposed to parental risk factors and is subsequently expressed fully in an adverse social environment. A recent study has found that children at high genetic risk for conduct problems are more likely to develop conduct disorder following maltreatment than are those at low genetic risk. It has not been demonstrated whether genetic propensity or adverse parenting alone can generate conduct disorder. However, a Danish study found that birth complications and maternal rejection predicted antisocial violence in late adolescence.

Gender differences in prevalence and trajectory have been identified. Whereas males predominate in disruptive behavior disorders prior to adolescence, prevalence rates among the two sexes are closer by age 15 years, due to an increase in covert, nonaggressive delinquent behavior among girls. Girls are more likely to follow the nonaggressive pathway with late onset, covert offenses, and a greater likelihood of recovery. Because of the emphasis on aggressive behavior in formal diagnostic schedules for conduct disorder, it is possible that the behavioral precursors and adult outcome of female conduct disorder have been obscured. Indirect aggression (e.g., spreading malicious rumors) is more common in girls.

Etiology

Psychosis, Epilepsy, & Brain Dysfunction

Careful history taking, mental status examination, neuropsychological testing, and electroencephalography of violent juvenile offenders often reveal hallucinatory experiences, mental absences, episodes of illogical thinking, lapses of concentration, memory gaps, suspiciousness, explosive aggression, and nonspecific electroencephalography abnormalities. These findings, along with the history of physical abuse and neglect often encountered among violent delinquents, have suggested that some antisocial youths could be experiencing covert psychosis or subclinical epilepsy caused by brain injury. An alternative explanation is that a high proportion of explosively aggressive youths harbor overt or residual posttraumatic stress disorder secondary to physical or sexual abuse and that their absences, hallucinations, lapses in concentration, and explosiveness represent dissociation stemming from unresolved trauma.

Psychophysiologic Theories

Childhood-onset, aggressive conduct disorder (in contrast to adolescent-onset, nonaggressive conduct disorder) is associated with low tonic psychophysiologic arousal, low autonomic reactivity, and rapid habituation. These characteristics may be associated with an impairment of avoidance conditioning to social stimuli, a failure to respond to punishment, and deficient behavioral inhibition. An imbalance between central reward and inhibition systems has been postulated. It is unclear whether these psychophysiologic phenomena are inherent, whether they are secondary to disruptive experiences in early childhood, or whether they are the result of an unstable lifestyle.

Neuroendocrine & Biochemical Theories

Research into the relationship between testosterone and aggressive crime has yielded inconsistent results. Several studies have found an association between low levels of 3-methoxy-4-hydroxyphenylglycol in cerebrospinal fluid and impulsive behavior in older youths. Other abnormalities in the dopaminergic and noradrenergic systems have been described, although only in very small population samples. Low levels of cerebrospinal 5-hydroxyindoleacetic acid, a serotonin metabolite, are associated with psychopathy, aggression, and suicide; and one study correlated defiance and aggression with low levels of whole blood 5-hydroxytryptamine. Another study has suggested a relationship between disruptive behavior disorder (i.e., conduct disorder and oppositional defiant disorder) and lower concentrations of cerebrospinal fluid somatostatin. These studies must be interpreted with caution because of the following limitations: (1) They have small sample sizes, (2) they gathered data from areas (i.e., cerebrospinal fluid) that are far “downstream” from the relevant brain areas (i.e., central neurotransmitter synapses), and (3) their cross-sectional correlative nature makes it difficult to determine the direction and timing of causal sequences. Many of the children in these studies experienced severe maltreatment; moreover, conduct disorder itself may generate traumatic experiences that could affect the neurochemical systems in question.

Neuropsychological & Neurodevelopmental Theories

Associations have been found among severe and extended child maltreatment, dissociative symptoms, chronic posttraumatic stress disorder, memory defects, and reduction in hippocampal size. Low circulating cortisol has been associated with emotional numbing in chronic posttraumatic stress disorder, and high cortisol levels have been associated with flashbacks.

Delinquent populations subjected to cognitive testing have consistently exhibited IQs about eight points below those of nondelinquent populations, a difference that persists when socioeconomic status is statistically controlled. This discrepancy is primarily the result of deficits in word knowledge, verbally coded information, verbal reasoning, verbally mediated response regulation, and metalinguistic skills. The most impulsive, aggressive subjects exhibit the widest discrepancy between verbal and performance IQs. These deficits probably antedate school entry and are associated with learning problems.

Research into time-orientation, impulsivity, sensation seeking, and locus of control in youths with conduct disorder has not yielded consistent results, possibly because juvenile delinquency is not homogeneous. In terms of moral reasoning, unsocialized aggressive delinquents operate at a preconventional level and have deficient role-taking abilities. The characteristic egocentrism, hedonism, unreflectiveness, and denial of responsibility of offenders have been associated with developmental immaturity of the frontal lobe and left hemisphere.

Psychoanalytic & Attachment Theory

Early psychoanalytic theories postulated a relationship between crime and unconscious guilt. Later studies described the deficient ego and superego functioning of adult criminals, with impairment in reality testing, judgment, affect regulation, object relations, adaptive regression, and synthetic functioning. A connection has been postulated between parental psychopathology and the parent's unconscious fostering of deviant behavior in the child.

The observation that early neglect and bond disruption were prevalent in delinquents who exhibited so-called affectionless psychopathy led attachment theorists to examine the contributions of emotional neglect, attachment disruption, separation, and object loss to sociopathy. Disruptive behavior patterns are postulated to stem from three complementary processes: disorganized attachment patterns, distorted affective-cognitive structures, and the motivational consequences of insecure attachment. Disruptive behavior patterns are thought to arise ultimately from a combination of neurobiological risk factors, attachment disturbance, inappropriate parenting practices, and pathogenic family ecology.

Child Maltreatment & Adverse Parenting Practices

Maternal depression has been linked, via disorganized attachment, to disruptive behavior in middle childhood. Marital conflict, domestic violence, parental neglect, and child maltreatment are also associated with later antisocial behavior. The effect of divorce on child behavior is likely to be mediated mainly by exposure to marital discord before, during, and after parental separation. Physical abuse is related to later aggressive behavior and can be transferred from one generation to the next. The prevalence of sexual abuse among girls with conduct disorder is very high. According to a recent study of delinquent girls placed in therapeutic foster care, the girls first engaged in sexual activity at age 6 years, on average.

The following adverse parenting practices convey a risk for antisocial behavior: low parental involvement in child-rearing; poor supervision; and harsh, punitive discipline. Characteristic parent–child interactions involve unclear communication; lax and inconsistent monitoring; lack of follow-through; unpredictable, explosive, coercive, harsh, and overpunitive verbal or physical discipline; and a failure to provide verbal reinforcement for desirable behavior. Parents tend to back down from their child's increasingly coercive demands until, unable to tolerate them further, they lash out angrily. At such times, the parents are likely to berate the child in terms of the same undesirable characteristics that their own parents ascribed to them. Thus parents unwittingly reinforce negative behavior, fail to model and reinforce desirable behavior, and at the same time distort the child's attributional style: the child is primed to view himself or herself as bad and to expect other people, particularly authority figures, to be hostile and uncaring.

The combination of aggressive, antiauthoritarian behavior and verbal reasoning impairment causes the child to fail at school, to perceive himself or herself as rejected by teachers and peers, and to gravitate toward like-minded companions. Aggregations of high-risk youths incite and perpetuate antisocial behavior, providing a training ground for criminality and drug abuse. The parents of disruptive children are likely to have difficulty in preventing their children from mixing with rogue companions who promote delinquent behavior.

Attributional Style

Children who are prone to conduct disorder develop a characteristic interpersonal style that reflects a complex interplay among the following factors: biological predisposition, adverse environment, distorted information processing, and the influence of peers. Aggressive children have been found to underutilize social cues, to interpret neutral or ambiguous cues as hostile, to generate few assertive solutions to social problems, and to expect that aggressive behavior will be rewarded. This is particularly likely in those children who, early in development, exhibit aggressive, hyperactive, impulsive behavior.

Sociologic Theories

The following sociologic factors are related to antisocial behavior: severe family adversity; multiple family transitions; unemployment; socioeconomic disadvantage; disorganized, crime-ridden neighborhoods; and the prevalence of juvenile gangs. Family adversity, family transitions, and low socioeconomic status are particularly likely to be associated with childhood-onset, aggressive conduct disorder. However, the effect of low socioeconomic status is nullified when the effect of adverse parenting practices is statistically controlled. Adverse family circumstances appear to affect the child via adverse parenting.

Sociologic research has generated five main theories concerning the roots of antisocial behavior: (1) social segregation theory, (2) culture conflict theory, (3) criminogenic social organization theory, (4) blocked-opportunity theory, and (5) theories to do with differential justice and labeling.

Social segregation theory postulates that disadvantaged social or ethnic groups, particularly recent immigrants, become relegated to decaying neighborhoods ringing the inner city. Socially disorganized slums become battlegrounds for competing ethnic groups and spawn criminogenic cultural organizations such as juvenile gangs. Economically blocked from mainstream culture, many residents seek a criminal solution whereas others tolerate or adapt to the prevailing criminal tradition.

Culture conflict theory relates the antisocial behavior of the children of socially disadvantaged immigrants to the confusion and disempowerment of immigrant parents, leading to a conflict between traditional parental control and the influence of the new society. Criminogenic social organization theorists have studied the informal organization of street gangs and their focal concerns with masculinity, toughness, status, the capacity to outwit others, a hunger for excitement, and the belief that life is dictated by fate rather than planning. Blocked-opportunity theorists have emphasized the function of the gang as an illegitimate means to acquire desirable amenities in a materialistic society that accords high status to affluence.

Alternative views suggest that differential delinquency rates are related to variations in the activity of police and juvenile justice authorities: the chances for apprehension are higher in areas where there is greater police surveillance. Labeling theorists suggest that delinquency is caused by designating a juvenile as “delinquent.” Evidence indicates that delinquent attitudes can be hardened by legal processing, but this is a contributory rather than a root cause of antisocial behavior.

Genetics

Studies have examined the concordance for adult criminality between monozygotic (MZ) and dizygotic (DZ) twins (determining heritability), the concordance for criminality between MZ twins reared apart (correcting for shared environment), and the prevalence of criminality in adopted-away offspring of adult criminals (separating environmental and genetic influences). In 10 twin comparison studies, the concordance rates for adult criminality have been up to 50% for MZ twins and 20% for DZ twins. In contrast, seven studies of adolescent antisocial behavior have demonstrated a high but equivalent concordance in MZ and DZ twins, suggesting a preponderant environmental effect. A recent metanalysis of 51 twin and adoption studies of antisocial behavior found that additive genetic and additive nonshared environmental factors were prominent. The influence of genetic and shared environmental factors may be greater during childhood, and of the non-shared environment in adolescence. Studies of the adopted-away offspring of adult criminals suggest an additive effect, for adult property crime, between biological predisposition and criminogenic environment. Interestingly, this effect does not appear to apply to aggressive crime.

Improvements in the subtyping of conduct disorder will likely lead to advances in genetic research. For example, recent studies found evidence for the heritability of an aggression trait, whereas little evidence was found for a genetic factor in adolescent-onset, nonpersisting delinquent behavior. Research into the genetics of adolescent antisocial behavior has been impeded by the tendency to regard conduct disorder as a homogeneous, categorically distinct disorder rather than as a loosely assorted conglomerate of dimensional types exhibiting multifactorial etiology (multiple causal factors), heterotypic continuity (the tendency for behavioral patterns to change over time), and equifinality (the tendency for different causal factors to result in a common phenotype).

Pedigree studies suggest an association between adult antisocial personality disorder (in men), alcoholism (in men), and hysteria (in women). Recent research suggests that antisocial personality disorder and alcoholism have separate modes of inheritance.

In summary, it appears likely that polygenic factors have a moderate influence on adult criminality, particularly in regard to recidivism for property offenses, and that adverse genetic and environmental influences interact. At this point, definitive studies have not been conducted with adolescents. Future research into the genetics of juvenile delinquency should examine subtypes of juvenile antisocial and aggressive behavior.

Three chromosomal abnormalities have been associated with antisocial behavior: 47XXY, 47XYY, and an abnormally long Y chromosome. These conditions are so uncommon as to be of little practical import. In developmentally retarded groups, the XXY anomaly may be associated with antisocial behavior. The XYY anomaly is characterized by tallness, hypotonia, hyperactivity, delayed language development, tantrums, electroencephalography abnormality, recidivism for minor property offenses, and (in one study) a sadistic sexual orientation. The long Y anomaly may also be associated with recidivism.

Clinical Findings

Signs and Symptoms

Children with conduct disorder are usually referred for evaluation during childhood or adolescence—by parents; caregivers; pediatricians; or educational, child welfare, or juvenile justice authorities—because their behavior has become intolerably disruptive or dangerous at home, in school, or in the community. Often the referral occurs in response to threatened, or actual, suspension from school.

The overlap among conduct disorder, oppositional defiant disorder, and ADHD has raised questions concerning the distinctiveness of each disorder. Furthermore, the many associated problems exhibited by these children dictate the need to gather diagnostic data from a number of informants (e.g., parents, the patient, teachers). Categorical diagnosis alone is almost useless for treatment planning. A comprehensive biopsychosocial evaluation is required with an assessment of the patient's perceptual-motor, cognitive, linguistic, academic, and social competencies; an analysis of family functioning; and an examination of the child's behavior in school, with peers, and in relation to the community. Clinical interviewing of the patient and the family allows the clinician to explore different areas in response to diagnostic hypotheses. Structured clinical interviews may be more reliable than semistructured interviews, but their rigidity and cumbersome nature virtually restrict them to research purposes.

Psychological Testing

Cognitive, educational achievement, and neuropsychological testing, while not helpful in categorical diagnosis, can provide important information concerning the patient's perceptual-motor, cognitive, and linguistic functioning and educational performance—data that are important in the design of a comprehensive treatment plan. Table 36–8 lists rating scales that are useful in diagnosis and, possibly, in the monitoring of treatment.

Differential Diagnosis (Including Comorbid Conditions)

Conduct disorder is likely to coexist with oppositional defiant disorder and ADHD, and with substance use disorder, learning disorder, depression, posttraumatic stress disorder, and other anxiety disorders. In longitudinal studies, the prevalence of ADHD declines with age, whereas the prevalence of conduct disorder rises. Oppositional defiant disorder and conduct disorder are temporally continuous (see “Prognosis” discussion later in this section), whereas conduct disorder and ADHD often coexist. The coexistence of conduct disorder and ADHD significantly complicates treatment and conveys a worse prognosis than the diagnosis of ADHD or conduct disorder alone.

Many youths with conduct disorder have specific developmental disorders, particularly reading disability and verbal and metalinguistic deficits. Conduct disorder is also associated with early-onset substance use and with a rapid progression to serious substance abuse. Childhood-onset conduct disorder is more likely to be associated with comorbidity than is adolescent-onset conduct disorder.

Dysthymia, major depressive disorder, and anxiety disorders have been described as comorbid with conduct disorder. Conduct problems may precede depression or become apparent after its onset. Completed or attempted suicide has often been associated with conduct problems, particularly explosive aggression. A high proportion of incarcerated delinquents have posttraumatic stress disorder, in full or subclinical form. Of patients with combined Tourette's syndrome and ADHD, 30% also have conduct disorder. Conduct disorder should be differentiated from mania, which is often associated with irritable, belligerent, and rule-breaking behavior.

Treatment

Conduct disorder is too complex a group of problems to be treated by a single method. Individually tailored combinations of biological, psychosocial, and ecological interventions will likely be most effective. The task is to find the most effective treatment combinations for different groups of children and adolescents with conduct problems. The following sections discuss the most common approaches to prevention and treatment.

Early Intervention Programs

Early intervention programs such as Head Start may have a preventative function. Head Start programs attend to the child's physical health and provide an early education program that prepares the child for elementary school. They also educate parents about child development and offer support in times of crisis. Early mental health intervention programs, such as Triple P and Fast Track, identify aggressive children and provide intensive parent education to counteract the poor communication, inconsistency, lack of follow-through, coercive discipline, and failure to model or reward prosocial behavior that so frequently accompany nascent conduct disorder. Both Triple P and Fast Track have demonstrated promising short-term effects, however, their long-term benefits are unclear.

Treatment Programs for School-Aged Children

Behavioral programs targeting parental effectiveness and the child's social problem-solving capacity, social skills, prosocial behavior, and academic functioning are more effective in the short term than are nonspecific treatment methods.

Treatment Programs for Adolescents

During the 1980s, a number of meta-analyses confirmed generally pessimistic impressions of the effectiveness of community and institutional interventions. During the past decade, however, several therapeutic approaches have had promising results.

The Adolescent Transition Program combines initial assessment with feedback and motivational enhancement, followed by a menu of interventions including family-focused training, family therapy, and comprehensive case management.

Evidence is accumulating that it is ineffective to treat youths who have conduct disorder in community or institutional groups. The contagious reinforcement of antisocial behavior generated by antisocial youth groups likely counteracts any benefit derived from group-oriented therapeutic programs. For that reason, therapeutic foster homes have been developed. Youths who would otherwise have been incarcerated are placed with specially trained foster parents who provide daily structure and support; institute an individualized point program; and ensure close supervision of peer associations, consistent nonphysical discipline, and social-skill-building activities supplemented by weekly individual psychotherapy. When treatment foster care was compared with group care, a significant reduction of offending was demonstrated in the 12 months following discharge. The most significant differences between treatment foster care and group care were in the capacity of treatment foster care to prevent the adolescent from associating with deviant peers and in the quality of discipline provided.

Multisystemic therapy provides home-based community treatment for violent antisocial and substance-abusing youths. Based on social ecological and family systems theory, and applying family preservation principles, multisystemic therapy aims to empower parents with parenting skills and to enable youths to cope with family, peer, school, and neighborhood problems. Multisystemic interventions target specific problems, particularly adverse sequences of behavior within and between ecological systems (e.g., between child, family, and school), and are continually evaluated from a number of perspectives. Interventions are designed to promote the generalization and long-term maintenance of therapeutic change. Strategic and structural family therapy, behavioral parent training, cognitive-behavioral therapy, and community consultation are combined in accordance with individualized treatment plans. Deviant peer contact is monitored, discouraged, and counteracted. Parent–teacher communication is promoted. Several controlled evaluation studies have demonstrated the efficacy of multisystemic therapy compared to juvenile correctional placement, conventional individual psychotherapy, and no specific treatment.

Psychopharmacologic Interventions

Until recently, conduct disorder was thought to be resistant to drug treatment. Medication was thought to be useful for treating comorbid problems, for example, ADHD (using stimulants, tricyclic antidepressants, buspirone, or serotonin reuptake inhibitors), anxiety ( using propranolol or bupropion), and explosive aggression ( using propranolol, carbamazepine, trazodone, or neuroleptics). The rationale for medication was based primarily on hypothetical reasoning and clinical impressions. Three controlled studies have now been completed. One study has demonstrated the efficacy of methylphenidate in reducing defiance, oppositionalism, aggression, and mood changes in outpatients age 5–8 years who were diagnosed as having conduct disorder, with or without ADHD. Another controlled study has demonstrated the effectiveness of divalproex, an “antikindling” agent, in reducing hyperarousal, anger, and aggressiveness in incarcerated adolescents. Divalproex appears to be particularly effective for those adolescents whose explosive aggression is related to posttraumatic stress disorder. A third controlled study has demonstrated the effectiveness of lithium in reducing aggressiveness in inpatient adolescents with conduct disorder. In three previous controlled studies of the effectiveness of lithium in conduct disorder, two demonstrated efficacy and one did not.

Prognosis

The developmental trajectories of the disruptive behavior disorders illustrate the principle of heterotypic continuity (the tendency of behavior patterns to evolve and change with development). For example, temperamental impulsiveness and oppositional defiant behavior in infancy and the preschool period may evolve to antiauthoritarian behavior and stealing during middle childhood; to assault, breaking and entering, risky sexual behavior, and substance abuse in adolescence; and to criminality in adulthood. Such a developmental pathway is the result of a complex interplay among biological, environmental, and ecological factors.

A recent meta-analysis of factor analyses of disruptive child behavior has yielded a two-factor solution: an overt/covert factor and an orthogonal destructive/nondestructive factor, with four quadrants: property violations (e.g., fire setting, stealing, vandalism); aggression (e.g., spitefulness, bullying, assault); oppositional behavior (e.g., anger, argumentativeness, stubbornness, defiance); and status violations (e.g., truancy, rule-breaking, substance use).

Oppositional defiant disorder usually precedes conduct disorder; and conduct disorder incorporates oppositionalism, however, only about 25% of preschoolers with oppositional defiant disorder progress to conduct disorder. In view of the similar pattern of risk factors between the two disorders, it has been contended that oppositional defiant disorder and conduct disorder do not merit a separate diagnostic status. Similarly, whereas by definition all adults with antisocial personality disorder have manifested conduct disorder in adolescence, only 25–40% of adolescents with conduct disorder progress to antisocial personality disorder. Conduct disorder in adolescent girls predicts internalizing disorders (e.g., depression, somatoform disorder) and antisocial behavior.

Aside from the oppositional defiant disorder–conduct disorder–antisocial personality disorder pathway, other developmental trajectories have been identified: an exclusive substance abuse pathway; a covert, nonaggressive pathway; and an aggressive, versatile pathway. The exclusive substance abuse pathway involves progression from less serious to more dangerous illicit drugs, without aggressive or nonaggressive delinquency. The covert, nonaggressive pathway proceeds from minor theft to serious property violations. The aggressive, versatile path has an early onset, is associated with early hyperactivity and impulsivity, and involves increasingly violent behavior (e.g., from frequent fighting to assaultive behavior). A fourth pathway, authority conflict, is described as progressing from oppositionalism to serious antiauthoritarianism. Many youths with conduct disorder cross over from one trajectory to another.