Influence of Child and Adolescent Psychiatric Disorders on Young Adult Personality Disorder Stephanie Kasen, Ph.D., Patricia Cohen, Ph.D., Andrew E. Skodol, M.D., Jeffrey G. Johnson, Ph.D., and Judith S. Brook, Ed.D.

Objective: This study examines associations between childhood psychopathology and young adult personality disorder in a random sample of 551 youths, who were 9 to 16 years old at first assessment. Method: Subjects were evaluated for DSM-III-R psychiatric disorders. Information was obtained prospectively from youths and their mothers at three points over 10 years. The predictive effects of prior axis I disorders and adolescent axis II personality disorder clusters A, B, and C on young adult personality disorder were examined in logistic regression analyses. Results: The odds of young adult personality disorder increased given an adolescent personality disorder in the same cluster. Prior disruptive disorders, anxiety disorders, and major depression all significantly increased the odds of young adult personality disorder independent of an adolescent personality disorder. In addition, comorbidity of axis I and axis II disorders heightened the odds of young adult personality disorder relative to the odds of a disorder on a single axis. Conclusions: Assessment of personality pathology before late adolescence may be warranted. Childhood or adolescent axis I disorders may set in motion a chain of maladaptive behaviors and environmental responses that foster more persistent psychopathology over time. Identification and treatment of childhood disorder may help to reduce that risk. (Am J Psychiatry 1999; 156:1529–1535)

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any psychiatric disorders, including disruptive disorders, anxiety disorders, and depressive disorders, have an onset in childhood or adolescence (1, 2). Longterm longitudinal studies have shown that those childhood disorders increase the risk of negative outcomes in late adolescence and adulthood (3–5), although the course of pathology across the child-to-adult transition still remains unclear (6). In contrast, the appearance of axis II personality disorders has been attributed primarily to late adolescence and adulthood. Personality pathology logically has its origins in childhood and adolescence (7); nonetheless, there is limited information available on what characteristics presage adult personality disorders. Received April 1, 1998; revisions received Oct. 26, 1998, and Feb. 16, 1999; accepted Feb. 24, 1999. From the Department of Psychiatry and the School of Public Health, Columbia University, New York; the Departments of Epidemiology and of Personality Studies, New York State Psychiatric Institute; and the Department of Community and Preventive Medicine, Mount Sinai School of Medicine, New York. Address reprint requests to Dr. Kasen, Unit 47, New York State Psychiatric Institute, 1051 Riverside Dr., New York, NY 10032; [email protected] (e-mail). The Children in the Community study from which data were obtained was supported by a W.T. Grant Foundation grant and NIMH grant MH-36971 (Dr. Cohen) and by National Institute on Drug Abuse grant DA-03188 (Dr. Brook).

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Antecedents of adult personality disorders, especially borderline and schizoid disorders, have been traced to personality disorder precursors observed in childhood (8, 9). Certain adult personality disorders also have been linked empirically to childhood psychiatric disorder, particularly the well-established association between conduct disorder and adult antisocial personality disorder (3, 5, 10). Less is known about the association between childhood affective disorders and later personality disorder, despite the high co-occurrence of affective disorders and personality disorder in adults, including mood disorders and the emotional dramatic (cluster B) and anxious fearful (cluster C) personality disorders (11, 12), and anxiety disorders and the odd eccentric (cluster A) and cluster C (13) personality disorders. Childhood antecedents of later personality disorder also have been investigated in more representative samples. Adolescent disruptive, anxiety, depressive, and substance use disorders were associated with elevated personality disorder dimensional scores obtained 6 years later in a community sample of young adults (14). In an epidemiological sample overlapping with the current study sample, behavioral and affective problems and immature social behavior in early and 1529

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middle childhood heightened the risk of adolescent personality disorder (15), and disruptive and affective syndromes measured later in childhood and in adolescence increased the risk of personality disorder symptoms in young adulthood (16). Childhood psychiatric disorders may precipitate a chain of behaviors and environmental responses that predispose the individual to a more persistent form of adult pathology reflected in axis II personality disorders. This study examined the link between childhood pathology and young adult personality disorder in an epidemiological sample. It is singular in that predictive effects of both prior axis I disorders and earlier manifestations of personality pathology on young adult personality disorder can be examined prospectively at the diagnostic level. In addition, the earlier focus on the outcomes of childhood disruptive disorders is broadened to include outcomes of childhood affective disorders. On the basis of prior evidence we anticipated associations between disruptive disorders and all personality disorder clusters (10, 14, 17), between anxiety disorders and personality disorder in clusters A and C (13, 14), and between major depression and personality disorder in clusters B and C (11, 12, 14). Because comorbid disorders are reported to be more debilitating than are outcomes of single disorders (18), we also examined whether the odds of a personality disorder in young adulthood are higher among youths with co-occurring axis I-axis II disorders than among youths with a disorder on a single axis. The following questions were addressed: Do childhood psychiatric disorders increase the risk of adult personality disorder, and, if so, is that risk independent of adolescent personality disorder? Does comorbidity between prior psychiatric and personality disorders heighten the risk of later personality disorder beyond their separate effects? METHOD Subjects Subjects were drawn from the Children in the Community study, a longitudinal investigation of risk factors and childhood psychopathology. In 1975, 976 families with a child between 1 and 10 years old were randomly sampled from two upstate New York counties (85% of those asked) (19). In the first follow-up in 1983, 722 families (74%) were reinterviewed, 156 families (16%) were lost to follow-up, and 49 families (5%) refused to continue participation; interviews were not conducted with the remaining 49 families because of study time constraints (44 families), death of the study child (three families), or severe mental retardation in the study child (two families). Because those lost to follow-up were disproportionately among the urban poor, 54 new families were randomly sampled from urban poverty areas in the original two counties and were added to the 1983 sample, for a total of 776 families. According to 1980 U.S. census data, the 1983 sample is closely representative of families in the sampled counties on income and family structure, urbanicity of residence, and other demographic characteristics (20). The 1985 follow-up included 734 families (94.7%) from the 1983 follow-up and 42 families from the original sample who were located but not reinterviewed in 1983. In all, 818 families were seen for the 1983 or 1985 interviews; of these, 714 (87.3%) participated in a

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third follow-up in 1992. The current study used data from families who participated in 1992 and in at least one prior follow-up. Youths from the 104 families who did not participate in 1992 were compared to youths from the 714 families who did, with regard to demographic characteristics and diagnostic measures used in the current study. Nonparticipants and participants, respectively, did not vary statistically in age at the time of the 1983 follow-up (13.7 versus 13.7 years) (two-tailed t=–0.06, df=1, 774, p=0.95) or the 1985 follow-up (16.4 versus 16.3 years) (two-tailed t=–0.87, df=1, 774, p=0.39) or in rates of disruptive disorders (14.4% versus 11.3%) (χ2=0.83, df=1, p=0.36), anxiety disorders (9.6% versus 14.4%) (χ2=1.76, df=1, p= 0.18), major depression (4.8% versus 5.7%) (χ2=0.15, df=1, p=0.70), cluster A personality disorders (8.1% versus 6.8%) (χ2=0.23, df=1, p=0.63), cluster B personality disorders (7.1% versus 7.2%) (χ2= 0.003, df=1, p=0.96), or cluster C personality disorders (8.1% versus 7.7%) (χ2=0.02, df=1, p=0.88). However, the proportion of boys was greater in nonparticipants than in participants (64.4% versus 49.0%) (χ2=8.62, df=1, p=0.003). The current sample was limited to the 551 youths who were 16 years of age or younger when the 1983 assessment took place. Most subjects were white (91%) and Catholic (59%), and 48% were male. Mean age was 12.7 years (SD=2.1) in 1983, 15.2 years (SD= 2.1) in 1985, and 21.1 years in 1992 (SD=2.2).

Procedure After a full explanation of study procedures, written informed consent was obtained from all participating mothers and from participating youths 13 or more years of age. Interviews of mothers and youths were conducted simultaneously but separately in their homes by pairs of trained lay interviewers. In all three follow-ups, mothers responded to an interview covering family background and parenting and to a diagnostic interview and questionnaire about the study child that covered psychiatric and personality pathology. Youths were interviewed on parallel diagnostic instruments and responded to interviews and self-report inventories about friends, school, and work.

Measures In the 1983 and 1985 follow-ups, DSM-III-R axis I diagnoses, including attention deficit hyperactivity disorder (ADHD), conduct disorder, oppositional defiant disorder, overanxious disorder, separation anxiety disorder, social phobia, and major depressive disorder, were derived from mothers’ and children’s responses to the Diagnostic Interview Schedule for Children (21). Information obtained from the Diagnostic Interview Schedule for Children was augmented with questions asked elsewhere in the protocol in order to adequately assess DSM-III-R symptoms. In keeping with current best practice, a positive response from either parent or youth was taken as evidence of symptom presence. In order to counteract known problems of specificity in diagnostic interviews, youths who met diagnostic criteria and had scaled symptom and impairment scores of two or more standard deviations above the sample mean were considered to have each disorder. Axis I disorders were grouped into disruptive disorders (ADHD, conduct disorder, oppositional defiant disorder), anxiety disorders (overanxious disorder, separation anxiety disorder, social phobia), and major depressive disorder in order to increase statistical power (by increasing group size) and to reduce type I error (by reducing the number of independent variables). Thus, some youths were assigned to more than one disorder group. In all three follow-up waves, DSM-III-R axis II diagnoses, including antisocial, avoidant, borderline, dependent, histrionic, narcissistic, obsessive-compulsive, paranoid, passive-aggressive, schizoid, and schizotypal personality disorder, were derived from mothers’ and youths’ responses to interview items written for that purpose (17) or adapted for adolescent respondents from the Personality Diagnostic Questionnaire (22) or the Structured Clinical Interview for DSM-III-R Personality Disorders (SCID-II) (23). It was anticipated that the instrument, like its predecessors, would have high sensitivity but low to moderate specificity. To address this problem, only youths who met diagnostic criteria in both the 1983 and 1985 assessments

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(average interval=2.5 years) for a personality disorder in the same personality disorder cluster were identified as having a personality disorder. The validity of personality disorder diagnoses made before late adolescence in this study was shown by the prediction of subsequent negative life outcomes, including poor occupational and educational achievement and later deviance (17). Assessment of young adult personality disorder was cross-sectional in nature; however, items, as in the Personality Diagnostic Questionnaire and SCID-II, were worded to elicit enduring deviant characteristics. Personality disorder diagnoses were grouped according to DSM-III-R clusters A (paranoid, schizoid, schizotypal), B (antisocial, borderline, histrionic, narcissistic), and C (avoidant, dependent, passive-aggressive). Obsessive-compulsive personality disorder, as assessed, did not relate to dysfunctional outcomes that characterized all other diagnoses; therefore, it was not included in cluster C. Antisocial personality disorder is not measured in children; therefore, it was measured and included in cluster B diagnoses only in the 1992 adult follow-up. As with the axis I disorders, youths could be assigned to more than one personality disorder cluster.

Statistical Analysis Logistic regression analyses estimated effects when age and sex were controlled. For each outcome, predictors were entered into the equation to assess effects of prior disruptive disorders, anxiety disorders, major depression, adolescent personality disorder in the same cluster, and comorbidity of axis I and axis II disorders. A high rate of comorbidity precluded adequate statistical tests of independent effects of multiple axis II groups in the same equation; thus, equations include consideration of adolescent personality disorder in the same cluster only.

RESULTS

Prevalence of Disorders

The prevalence of all disorders is shown in table 1 for the total sample and separately for girls and boys. Yates’s corrected chi-square values for significant sex differences are given in the text. Axis I psychiatric disorders. By 18 years of age, almost 12% of the sample had a disruptive disorder at one or both youth assessments, and about half as many had major depression. About 15% had an anxiety disorder. Overall, about one of four youths was diagnosed with one or more disorders. Compared to boys, girls had significantly higher rates of anxiety disorders (19.2% versus 10.6%) (χ2=7.22, df=1, p