Progression From Conduct Disorder to Antisocial Personality Disorder Following Treatment for Adolescent Substance Abuse

One hundred sixty-six adolescents (40% of whom were female) were recruited from two inpatient substance abuse treatment programs in metropolitan San Diego as part of an ongoing longitudinal research project. Consecutively admitted patients were recruited if review of hospital records and structured interviews noted no evidence of a DSM-III-R axis I psychiatric disorder (other than conduct disorder) predating the onset of substance abuse. The inclusion criteria required 1) the participation of a resource person (usually a parent) to corroborate information regarding the adolescent and 2) residence within 50 miles of the research facility.

The current study used data from in-treatment interviews and interviews 4 years after treatment for those participants who met the criteria for conduct disorder at the time of treatment. Of the original study group, 88% (N=146) completed 4-year interviews. Of these, nine were excluded from the present study (five who were not 18 years old at the 4-year follow-up and four who did not meet the criteria for a diagnosis of conduct disorder), resulting in a final study group of 137 participants. The mean age of the participants at the 4-year follow-up time point was 20.0 years (SD=1.1). The study group was 39% female (N=53) and predominantly Caucasian (75%), with 6% Hispanic, 5% African American, and 14% from other ethnic subgroups. The socioeconomic status of the participating families ranged from unskilled laborer to college-educated professional.

Chart reviews were used to screen consecutively admitted patients to the inpatient treatment facilities for eligibility for the study, after which potential participants were recruited during the second week of treatment. Written informed consent was obtained separately from each adolescent and a parent or legal guardian after the procedures had been fully explained. A 90-minute confidential interview was administered separately to the teenager, after which a resource person was interviewed to provide corroborative information. Follow-up interviews were conducted separately with the adolescent subjects and the resource persons.

Eighty-four (61%) of the participants met the DSM-III-R criteria for the antisocial personality disorder diagnosis. The significance level for comparisons of baseline characteristics was set at 0.006 so as to provide a type I error rate of ≤5% for multiple analyses. Table 1 displays demographic data, baseline alcohol and drug use characteristics, and variables included in the logistic regression for the two diagnostic outcome groups. Male subjects were disproportionately represented in the antisocial personality disorder group (71%, N=60) compared to female subjects (29%, N=24) (χ²=9.37, df=1, p<0.005); however, the two groups were comparable in race/ethnicity, age, and socioeconomic status at the time of admission to treatment. The subjects meeting the criteria for antisocial personality disorder had significantly greater drug use but not alcohol use during the 3 months before treatment; they did not differ on lifetime use of alcohol or drugs.

This study examined prospectively the development of antisocial personality disorder during the 4 years following treatment for adolescent substance abuse. The results largely supported hypotheses derived from developmental models for the persistence of antisocial behavior and previous empirical evidence of the relationship between substance abuse and progression of antisocial behavior. In addition, these findings are consistent with retrospective studies of adult substance abusers that have demonstrated an association between early onset of antisocial behavior and a greater extent and severity of antisocial behavior (25, 26).

Of the variables included in the logistic regression, early onset of conduct disorder behavior (at age 10 or earlier), greater diversity of conduct disorder behavior occurring independent of substance involvement, and greater recent use of drugs were significant predictors of the antisocial personality disorder diagnosis in late adolescence/early adulthood. Our findings are largely consistent with theoretical models of the persistence of antisocial behavior that emphasize the importance of early, severe, and diverse deviant behavior in predicting lifelong antisocial behavior (14, 16). In addition, the fact that involvement with drugs prior to treatment was found to add to the prediction of antisocial personality disorder highlights the role of substance use in the pro~gression of antisocial pathology among youths with a history of substance abuse.

As anticipated, study participants who developed antisocial personality disorder by 4 years after treatment for adolescent substance abuse had poorer alcohol and drug use outcomes than did those not diagnosed with antisocial personality disorder. Our results indicated significantly higher overall levels of involvement with alcohol, more symptoms of alcohol and drug dependence, and more days on which substances were used in the group with an antisocial personality disorder diagnosis. A reliance on alcohol and drug use for coping with life stress may be particularly likely given the history of polysubstance abuse in this study group (18, 27). This finding also appears consistent with the notion of “snares” as discussed by Moffitt (15) and her colleagues, in which certain consequences or features of antisocial behavior serve to limit options for escaping an antisocial lifestyle. In the present study, heavier involvement with alcohol and drugs following treatment may have served to limit options for engaging in more prosocial activities or behavior, restricted environmental contexts to more “risky” settings, and functioned to perpetuate a deviant lifestyle.

Examination of antisocial personality disorder in relation to functioning in major life domains yielded results largely consistent with our predictions. In the domains of school/work, interpersonal relations, and legal difficulties, the greater extent of problems reported by the subjects with antisocial personality disorder appears largely related to involvement with alcohol and/or drugs. While completion of schooling and current employment status did not differ between the groups, problems attributed to alcohol and/or drug use were significantly more common among the participants with antisocial personality disorder in each of the aforementioned domains. Thus, the greater substance involvement by those progressing to antisocial personality disorder appears to exacerbate difficulties in functioning across these important domains of young adult functioning. When we examined emotional functioning, subjects in the group with antisocial personality disorder reported more overall help seeking for psychological problems and greater overall anxiety and depression. Therefore, it may be that the persistence of antisocial behavior in this study group was influenced by additional psychopathology. The substance abuse and emotional difficulties apparent in the group with antisocial personality disorder may well be reciprocally related in such a way that each serves to exacerbate the other. The current results indicate the prominence of substance use in relation to poorer overall functioning, suggesting that alcohol and drug abuse may be inextricably involved in the progression of antisocial pathology among young people with a history of substance abuse.

The present data on the progression of antisocial behavior suggest continued difficulties for the participants diagnosed with antisocial personality disorder. Moffitt (15) has proposed that the persistence of antisocial behavior reflects in part the limited options for change available to antisocial individuals. The results of the present study can be interpreted to support this conceptualization. For example, the poorer relationship functioning that was apparent among the subjects with antisocial personality disorder may reflect various deficits in interpersonal and cognitive functioning as well as the negative consequences of continued substance involvement. The likelihood of remediation or improvement of skills critical to successful functioning appears rather limited for individuals with antisocial personality disorder who have passed the critical period during which many cognitive and interpersonal skills are typically acquired and refined. In addition, continued substance involvement exhibited by youths with antisocial personality disorder may serve to limit future opportunities for acquisition of skills and is likely to create new problems, the consequences of which may further promote substance involvement and restrict opportunities for emerging from an antisocial lifestyle.

The findings of this study must be considered in light of several limitations. First, the current method of determining an antisocial personality disorder diagnosis from the Conduct Disorder/Antisocial Personality Disorder Questionnaire has not been validated in comparison with standardized diagnostic measures. However, this instrument has demonstrated validity and utility for obtaining a diagnosis of conduct disorder (5, 18), thereby increasing our confidence in the antisocial personality disorder diagnoses in this study. Another issue concerns the accuracy of retrospective information used to assess the onset of early conduct disorder behavior. The utilization of multiple reporters has been found useful in retrospective assessment of childhood problem behavior and may mitigate some of the concerns regarding potential recall bias (28). The hypothesized variables successfully predicted progression to antisocial personality disorder on the basis of information collected during adolescence, suggesting that careful assessment of retrospective information can be used to predict continuity of antisocial behavior. Further, the results of this study are supported by the convergence of findings across our three investigations that have demonstrated a relationship between early conduct disorder behavior and treatment outcome. The reliance on self-report data for assessment of anxiety, depression, and illegal behavior suggests caution in interpreting our findings. Future studies that use more formal diagnostic procedures for assessing these variables are needed to replicate the present findings. Another limitation of this study is that not all factors believed to be important to the progression of antisocial behavior are considered in the present model. Finally, the inclusion of male and female subjects in the present analyses represents a distinction from the predominantly male-based body of literature on the development of antisocial behavior.

The ability of variables assessed during treatment to significantly predict antisocial personality disorder status 4 years later has important clinical implications. Adolescents who present for treatment of substance abuse may appear to be uniformly conduct disordered, and thus attention to conduct disorder behavior may seem to add little information for prognosis or treatment planning. However, the findings of this study suggest that careful assessment of the extent of conduct disorder behavior and identification of behavior that occurs prior to and independent of substance abuse may serve to identify individuals at risk of persisting in antisocial behavior. Adolescents whose conduct disorder behavior occurs primarily in the context of substance use or appears following the onset of substance abuse, and who demonstrate such behavior across few settings, are likely to desist from antisocial behavior and thus may not require as much intervention beyond treatment for substance abuse. In contrast, those who appear to be on a lifetime course of antisocial behavior may benefit from more intensive targeted interventions. For example, it has been shown that multisystemic therapy (29) is effective in producing long-term reductions in violent and criminal offenses among serious juvenile offenders, and as such it may represent a useful adjunct intervention for substance-abusing youths at risk for persistent antisocial behavior.

In summary, this investigation is one of the first to examine prospectively the development of antisocial personality disorder in the context of concomitant adolescent substance abuse and conduct disorder. These data illustrate some of the developmental factors that underlie the poor prognosis that accompanies comorbid antisocial personality disorder and substance abuse; they also demonstrate how the matrix of problems encountered by antisocial youths may function to sustain problem behavior and limit options for change. However, our findings should not be interpreted to suggest that antisocial youths do not benefit from treatment. Those with persistent antisocial psychopathology may enter treatment with poorer overall functioning, and thus between-group differences may reflect more limited improvement rather than treatment failure. Future research on the factors that interact to maintain and reinforce the concordance between antisocial behavior and substance abuse is needed to further our understanding of mechanisms underlying this process.

Received March 21, 1997; revision received July 8, 1997; accepted Sept. 18, 1997. From the School of Medicine, University of California, San Diego; the Department of Psychiatry, University of California, San Diego; and the San Diego VA Medical Center. Address reprint requests to Dr. Myers, Psychology (116B), VA Medical Center, 3350 La Jolla Village Dr., San Diego, CA 92161; [email protected] (e-mail). Supported by grants from the National Institute on Alcohol Abuse and Alcoholism (AA-07033), the Research Service of the Department of Veterans Affairs, and the National Institute on Drug Abuse (DA-09181).