The Correlates of Comorbid Antisocial Personality Disorder in Schizophrenia

12 Pages·2005·1.04 MB·English

The Correlates of Comorbid Antisocial
Personality Disorder in Schizophrenia
by Paul Moran and Sheilagh Hodgins
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Abstract cent of the men and 17 percent of the women with schizo- s://a
phrenia met criteria for DSM-III-R APD, in a sample of c
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More than 15 years ago, findings from the male forensic patients with schizophrenia the prevalence de
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Epidemiological Catchment Area Study indicated that of APD was estimated to be 27 percent, and in a sample ic
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antisocial personality disorder (APD) is more preva- of incarcerated offenders with schizophrenia the preva- u
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lent among persons with schizophrenia than in the lence of APD was 63 percent (Hodgins et al. 1996). .c
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general population. The present study analyzed data APD indexes a pattern of antisocial behavior that
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from a multisite investigation to examine the corre- emerges early in life and that remains stable across the ch
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lates of APD among 232 men with schizophrenic disor- life span. The diagnosis is given when an individual pre- o
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ders, three-quarters of whom had committed at least sents a "pervasive pattern of disregard for and violation of re
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one crime. Comparisons of the men with and without the rights of others occurring since age 15 years" (APA ia
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APD revealed no differences in the course or sympto- 1994, p. 649) and behaviors present before age 15 that u
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matology of schizophrenia. By contrast, multivariate meet criteria for a diagnosis of conduct disorder as indi- tin
mAPoDde lws itcho nsfuirbmsteadn cset raobnugs ea, ssaotcteianttiioonns/ coofn cceonmtroartbioidn cwahteicdh b tyh e" ar irgehptest iotifv eo tahnedrs p oerr smistaejnotr paagtete-ranp porfo bperihaatev iosor ciin- /article
problems, and poor academic performance in child- etal norms or rules are violated" (APA 1994, p. 90). Data -ab
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hood; and in adulthood with alcohol abuse or depen- from the ECA Study indicate that the risk of schizophre- tra
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dence and deficient affective experience (a personality nia increases in a linear fashion with the number of con- t/3
style indexed by lack of remorse or guilt, shallow duct disorder symptoms (Robins and Price 1991). 0/4
affect, lack of empathy, and failure to accept responsi- Furthermore, a prospective investigation of a New /7
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bility for one's own actions). At first admission, men Zealand birth cohort revealed that 40 percent of the /1
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with schizophrenia and APD presented a long history cohort members who developed schizophreniform disor- 3
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of antisocial behavior that included nonviolent offend- ders by age 26 presented conduct disorder as children 7
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ing and substance misuse, and an emotional dysfunc- and/or adolescents (Kim-Cohen et al. 2003). Consistent b
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tion that is thought to increase the risk of violence with these findings are the results of prospective studies gu
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toward others. Specific treatments and management of children at high risk for schizophrenia (by virtue of s
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strategies are indicated. having a mother with the disorder) that have identified a n
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Keywords: Schizophrenia, antisocial personality subgroup of boys with behavior problems (Asarnow 6 N
disorder, treatment, prevention, etiology. 1988). In the Copenhagen High-Risk project, it was boys o
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Schizophrenia Bulletin, 30(4):791-802, 2004. with behavior problems who developed predominately m
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positive-symptom schizophrenia (Cannon et al. 1990). e
The prevalence of antisocial personality disorder (APD) Findings from other prospective investigations (see, e.g., r 20
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is elevated among men and women with schizophrenia as Hodgins and Janson 2002) and several retrospective stud- 8
compared to the general population. The Epidemiological ies of clinical samples of men with schizophrenia confirm
Catchment Area (ECA) Study revealed that the preva- that a subgroup of males who develop schizophrenia dis-
lence of schizophrenia was 6.9 times higher among men
with APD and 11.8 times higher among women with APD
than among men and women generally (Robins et al.
Send reprint requests to Professor S. Hodgins, Box PO23, Department
1991; Robins 1993). Other studies have confirmed these
of Forensic Mental Health Science, Institute of Psychiatry, De Crespigny
findings. For example, in a community sample, 23 per- Park, Denmark Hill, London SE5 8AF; e-mail: [email protected].
791
Schizophrenia Bulletin, Vol. 30, No. 4, 2004 P. Moran and S. Hodgins
play a pattern of antisocial behavior both before and after orders and another set conferring a vulnerability for exter-
the onset of schizophrenia (Hodgins 2004). nalizing problems. Just as investigations of hereditary fac-
Comorbid APD amplifies the suffering of people with tors associated with schizophrenia have not taken account
schizophrenia. Among men with schizophrenia, comorbid of antisocial behavior patterns, studies of the role of
APD is associated with persistent criminality, much of it obstetric complications have not taken account, for exam-
nonviolent, that begins in adolescence and often leads to ple, of the damage that maternal antisocial behavior could
imprisonment (Hodgins and Cote 1993), with early-onset do to the developing fetus.
substance use, unemployment, and homelessness Some children with conduct disorder (Frick et al.
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(Tengstrom and Hodgins 2002). Other studies suggest that 2003) and some adults with APD (Cooke and Michie o
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the presence of APD among persons with schizophrenia is 1997) also display two personality traits included in the n
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associated with an increased severity of substance abuse, syndrome of psychopathy: arrogant and deceitful interper- ad
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a greater severity of symptoms of psychosis, higher rates sonal conduct, and deficient affective experience. The first d
of police contact, and with violent behavior (Mueser et al. trait does not characterize men with schizophrenia, but from
1997, 1999; Gandhi et al. 2001; Moran et al. 2003). deficient affective experience is elevated among offenders h
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Furthermore, a small number of studies have reported that with schizophrenia (Tengstrom and Hodgins 2002) and s
the presence of comorbid APD is associated with poor overlaps with negative symptoms. It includes four items: ://a
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outcome for the treatment of schizophrenia (Torgalsb0en lack of remorse or guilt, shallow affect, lack of empathy, d
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1999; Tyrer and Simmonds 2003). The lack of studies of and failure to accept responsibility for one's own actions. m
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the impact of comorbid APD on response to treatment and It is hypothesized that this trait emerges early in life, con- .o
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outcome in schizophrenia is surprising. This lack may tributes to the initiation and maintenance of antisocial .c
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result, at least in part, from the reluctance of individuals behavior, and is associated with repetitive violence m
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with both of these disorders to participate in research (Cooke and Michie 1997; Blair 2003). c
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(Hodgins et al., in press). Such patients pose enormous In summary, there is compelling evidence of an asso- izo
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difficulties to clinical services, as they fail to comply with ciation between schizophrenia and APD and of the harm- h
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treatment and persist in using drugs and alcohol. ful consequences for individuals afflicted with both disor- nia
The association between schizophrenia and APD may ders. This association has been the focus of comparatively bu
also have important implications for understanding the little research, and the available findings suggest that it lletin
etiology of schizophrenia. For example, consider the evi- may have implications for treatment provision and etiol- /a
dence on hereditary factors for schizophrenia and for ogy. The present study was a secondary analysis of data rtic
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APD. One hypothesis suggests that genetic factors associ- collected from the Comparative Study of the Prevention -a
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ated with schizophrenia confer vulnerability for antisocial of Crime and Violence by Mentally 111 Persons (Hodgins stra
behavior. This hypothesis is supported by findings from et al., in press). The sample included 232 men with schiz- ct/3
family studies demonstrating an elevated prevalence of ophrenia who were extensively assessed at discharge from 0
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antisocial behavior and criminality among relatives of either a general psychiatric hospital or a forensic psychi- /7
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persons with schizophrenia (Silverton 1985; Kay 1990) atric hospital in one of four sites. These men were 1/1
and by the results of two adoption studies showing that recruited into a multisite study of community treatment. 93
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schizophrenia in the parental generation increases the risk The four sites (southern British Columbia, Canada; 07
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of criminality among the offspring (Heston 1966; Finland; the state of Hessen in Germany; and southern b
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Silverton 1985). An alternative hypothesis suggests that Sweden) were selected because they all included large g
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individuals with schizophrenia and APD have inherited a catchment areas in which the centralized forensic services es
vulnerability for externalizing problems that includes sub- treated almost all, if not all, mentally ill persons prose- t on
stance abuse. A recent meta-analysis of twin and adoption cuted for a criminal offense. The aim of the study was to 26
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studies estimated the heritability of externalizing prob- identify characteristics of persons with schizophrenia and o
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lems at 0.41 (Rhee and Waldman 2002). Children vulnera- APD that may be of relevance for treatment and service em
ble for schizophrenia who carry the low-activity variant of provision, the prevention of criminal behavior, and the eti- be
the functional polymorphism in the gene encoding ology of these associated disorders. r 2
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monoamine oxidase A genotype could develop stable anti- 8
social behavior as a result of an interaction between this
Method
hereditary factor and severe child abuse (Caspi et al.
2002). It has been reported that individuals with schizo-
phrenia spectrum disorders mate disproportionately with Sample. The sample included 232 men with schizophre-
antisocial individuals (Parnas 1988). This could be nia who had been discharged from either a general psychi-
another way in which children inherit one set of genes atric hospital or a forensic psychiatric hospital in four
conferring a vulnerability for schizophrenia spectrum dis- sites (southern British Columbia, Canada; Finland; the
792
Comorbid Antisocial Personality Disorder Schizophrenia Bulletin, Vol. 30, No. 4, 2004
state of Hessen in Germany; and southern Sweden). One childhood and adolescence (defined as birth to age 18)
hundred and forty-five (62.5%) of the men had been dis- was obtained from participants; family members; and
charged from a forensic psychiatric hospital, and 87 school, military, criminal, and medical files. A consensus
(37.5%) had been discharged from a general psychiatric decision about each variable was made by the research
hospital. The proportion of the total sample recruited in psychiatrist and research assistant after all information
each site was as follows: Canada, 39 percent (n - 90); had been extracted from files and interviews with patients
Finland, 25 percent (n = 57); Germany, 27 percent (n = and family members had been completed.
63); and Sweden, 9 percent (n = 22). The mean age of the Parents' characteristics. Information on parents
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sample was 38 years (standard deviation [SD] = 11.3), and was obtained from the participants, family members, and o
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the principal DSM-IV (APA 1994) diagnoses were schizo- in some cases records. nlo
phrenia (n = 186), schizoaffective disorder (n = 45), and a
Diagnoses. Primary, secondary, and tertiary diag- d
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tshceh iztootpahl resanmifoprlme (dni s=o r5d1e)r ((9n5 =% 1c)o. nTfwideenntcye- twinot eprvearcl e[nCt Io]:f nSotrsuecst—ureldif eCtilmineic aaln dIn tceurvrrieewnt —fowr eDreS Mm-IaVd e (SuCsiInDg) tfhoer d from
o1f6 .A7P-2D7:. 32)6 mpeertc DenStM (n-F -V 3 c8r)i toerfi ath feo fro are cnosimc oprabtiide ndtsia agnndo s1is5 Axis I and II disorders (Spitzer et al. 1992). Experienced http
psychiatrists who were trained by the developers of the s
percent (n = 13) of the general psychiatric patients. In instrument administered the SCID. The psychiatrists in ://ac
addition, 57 percent (n = 132) (95% CI: 50.5-60.3) of the a
the four sites all spoke English and were trained and d
sample had a diagnosis of alcohol abuse and/or depen- em
dence, and 44 percent (n = 101) (95% CI: 37.2^9.9) of Etenstgeldis hu.s iInngf ovrmidaetoiotanp efdro imnt eprvarietiwcisp awnittsh; pfaamtieilnyt s mspemeabkeinrsg; ic.o
the sample had a diagnosis of drug abuse and/or depen- up
school, medical, and social service records; and treatment .c
dence. Psychosocial functioning was low; the mean score o
staff was used to make diagnoses. The use of multiple m
on the Global Assessment of Functioning Scale (GAF; /s
sources of information was particularly important to cor- c
Spitzer et al. 1992) for the sample was 49.3 (SD = 13.0), roborate and confirm the diagnosis of conduct disorder. hizo
and 60 percent (n = 139) had never had an intimate rela- p
Interrater reliabilities calculated on 38 cases reached K = h
tionship. The mean age at first admission to the hospital re
was 24.8 years (SD = 8.8), and the mean number of admis- 1.0 for the principal diagnosis of schizophrenia and K = nia
sions was 8.0 (SD = 7.1). Three-quarters (n = 173) of these 0.85 for APD. bulle
men had been convicted of at least one crime: 99 percent Psychosocial functioning. Psychosocial functioning tin
o(nf -th e1 4g3e)n eorfa lt hpes yfocrheinastricic ppaatiteienntsts .a nTdh e3r4e pweerrcee n3t 8( np a=r ti3c0i-) wteraesd i nthdee xSeCd IbDy afsosuers sveadr ipabsylecsh. oPssoycciahli afturniscttsi ownihnog aidnm tihnei s6- /article
pants (16%) who had committed at least one homicide or months prior to discharge using the GAF. Interrater relia- -ab
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attempted homicide and all were recruited from a forensic bilities calculated on 33 cases were estimated at K = 0.61. tra
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hospital. The mean total number of crimes in the entire Information about intimate relationships, employment his- t/3
sample was 9.9 (SD = 19.2), and the mean total number of tory, and compulsory military service (for the Finnish, 0/4
violent crimes was 2.6 (SD = 5.0). German, and Swedish participants) was obtained from /79
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participants, family members, and official records. /1
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Measures Symptoms. Psychotic symptoms were assessed 31
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Sociodemographic information. Information on using the Positive and Negative Syndrome Scale (Kay et 73
sociodemographic characteristics was collected from the al. 1987). Interrater agreement, calculated on 37 cases, by
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participant, family members, and medical files. reached K = 0.70 for positive symptoms and K = 0.52 for ue
History of psychiatric treatment. Information on negative symptoms. st o
previous psychiatric treatment was extracted from hospi- Personality. Trained research psychiatrists assessed n 2
tal files. psychopathic traits using the Psychopathy 6 N
Criminality. Information on criminality was Checklist-Revised (PCL-R; Hare 1991). Three factor ov
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extracted from official criminal records. Throughout this scores, as described by Cooke and Michie (2001), were m
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article, the term convictions is used broadly to include calculated: (1) arrogant and deceitful interpersonal con- er 2
judgments of nonresponsibility due to a mental disorder. duct (items 1, 2, 4, and 5); (2) deficient affective experi- 01
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Violent crimes are defined as all offenses causing physical ence (items 6-8, and 16); and (3) an impulsive and irre-
harm, threat of violence or harassment, all types of sexual sponsible behavioral style (items 3, 9, and 13-15).
offenses, illegal possession of firearms or explosives, all Interrater agreement, calculated on 38 cases, ranged from
types of forcible confinement, arson, and robbery. All K = 0.85 for the total scores, to K = 0.75 for arrogant and
other crimes are defined as nonviolent. deceitful interpersonal conduct, K = 0.75 for deficient
Childhood and adolescent history of antisocial affective experience, and K = 0.89 for impulsive and irre-
behavior and academic performance. Information on sponsible behavioral style.
793
Schizophrenia Bulletin, Vol. 30, No. 4, 2004 P. Moran and S. Hodgins
Procedure. Within each site, each participant with a APD, compared to those without APD, met criteria for
diagnosis of a major mental disorder being discharged alcohol and drug abuse or dependence. The history of
from the forensic hospital was approached and invited to treatment in psychiatric services, psychosocial function-
participate in the study. If the participant formally con- ing, and symptoms at discharge did not distinguish those
sented to participate, the SCID (Spitzer et al. 1992) was with APD. As would be expected because of the overlap
completed. If a diagnosis of a major mental disorder was between symptoms of APD and items on the PCL-R, the
confirmed, the participant was included in the study and participants with APD obtained higher mean total PCL-R
the other interviews and assessments were completed and scores and higher scores on the factor indicating an D
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information was collected from files and collaterals. impulsive and irresponsible behavioral style. Notably, w
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Patients from general psychiatric hospitals in the same however, they also obtained higher scores on the trait of lo
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geographical region who had the same sex, similar age deficient affective experience, which does not overlap de
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(±5 years), and the same principal diagnosis were identi- with APD symptoms. The statistical significance of this fro
fied and also invited to participate in the study. If the prin- comparison, however, diminished after applying the m
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cipal diagnosis was confirmed by the research psychiatrist Bonferroni correction. ttp
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using the SCID, the same information was collected as for ://a
the other participants. c
Childhood and Adolescent Characteristics. a
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Comparisons of childhood and adolescent characteristics m
Data Analysis. All analyses were performed using Stata of participants with and without comorbid APD are dis- ic.o
version 7 (StataCorp 2001). Univariate associations played in table 1. Participants with APD, as compared to up
between a DSM-IV diagnosis of comorbid APD and all those without, were significantly more likely to have .co
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baseline variables were examined using chi-square tests experienced attention and concentration problems. While /s
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and, where appropriate, the Fisher exact test for categori- 82 percent of the men with APD abused substances before hiz
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cal variables and t tests for continuous variables. A age 18, so did 41 percent of those without APD. The aca- p
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Bonferroni correction was applied to account for the use demic performance of the participants with APD was re
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of multiple statistical tests (p = 0.001). Three multivariate poorer than that of participants without APD, as early as iab
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models of childhood, adult, and adult criminal correlates elementary school, and a significantly greater number of lle
of comorbid APD were then determined using forward participants with APD had been placed in an institution tin
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stepwise logistic regression. To ensure that models were before 18 years of age. A number of other comparisons rtic
based on exactly the same data, participants with missing were initially statistically significant at the 5 percent level, le-a
values for relevant variables were excluded before model- but the differences failed to meet significance after the bs
ing. Each model started with the variables that were most Bonferroni correction was applied: earlier onset of symp- tra
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significantly associated with comorbid APD at a univari- toms of hyperactivity, depression, and substance misuse; t/3
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ate level. Subsequent variables were then added and like- noncompletion of high school education; physical abuse /4
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lihood ratio tests were used to determine the significance before age 12 years; paternal criminality; and paternal 91
of adding the new variables to the model. Significant pre- substance abuse. No comparisons of criminality, sub- /19
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dictors from the childhood/adolescent model and the adult stance abuse, and mental illness among the mothers and 1
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model were then entered into a series of models, to iden- siblings were statistically significant. 73
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tify the variables that most parsimoniously predicted y
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comorbid APD. u
History of Criminal Offending. As displayed in table 1, e
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compared to men without APD, participants with APD t o
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Results committed a significantly greater total number of crimes, 2
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committed a significantly greater number of nonviolent N
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There was no difference in the mean age at entry into the crimes, and were more likely to have committed a crime ve
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study or the parental occupational status of men with before their first admission to general psychiatric services. b
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comorbid APD compared to those without comorbid APD Notably, neither the mean number of violent crimes nor r 2
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(table 1). the proportion of participants in each group who had com- 1
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mitted a homicide differed.
Adult Mental Disorders, Cognitive Functioning, and
Personality. The men with and without comorbid APD Multivariate Models. The first model included the child-
did not significantly differ with regard to principal diag- hood and adolescent variables that significantly distin-
noses, the ages at onset of the prodrome or psychotic guished the participants with and without comorbid APD.
symptoms, or the mean number of positive and negative The analysis included 221 participants with complete
symptoms. A significantly greater proportion of men with data. Four predictor variables were entered into this
794
Comorbid Antisocial Personality Disorder Schizophrenia Bulletin, Vol. 30, No. 4, 2004
Table 1. Comparisons of the characteristics of men with schizophrenia and schizoaffective disorder with and
without comorbid APD
Variable APD No APD Test P
Sociodemographic characteristics
Mean age (yrs) 37.5 (SD= 11.7) 38.3 (SD= 11.2) 4230, n = 232) = 0.5 0.06
Father's occupation
White collar or professional 16% (7) 30% (47) X2(1,n= 199) = 3.6 0.06
Mother's occupation D
White collar or professional 15% (7) 19% (31) X2(1,n=207) = 0.4 0.05 ow
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Diagnoses a
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Principle diagnosis ed
Schizophrenia 78% (40) 81% (146) X2(2, n = 232) = 3.6 0.2 fro
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Schizoaffective disorder 20% (10) 19% (35) h
Schizophreniform 2%(1) — ttp
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Mean age of onset of prodrome (yrs) 19.0 (SD = 5.6) 20.3 (SD= 6.7) 498, n= 100) =-0.9 0.4 ://a
Mean age of onset of psychotic 22.3 (SD = 7.9) 24.1 (SD = 7.7) 4193, n= 195) = 1.3 0.2 c
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symptoms (yrs) de
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Mean age of first hospitalization (yrs) 23.1 (SD = 7.8) 25.3 (SD = 9.0) 4230, n = 232) = 1.6 0.1 ic
Mean no. of admissions to hospital 9.1 (SD = 8.6) 7.7 (SD = 6.6) 4230, n = 232) = 1.2 0.2 .o
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Symptoms .c
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Mean no. of positive symptoms rated 3 2.1 (SD= 1.9) 2.1 (SD = 2.1) t(225, n = 227) = 0.2 0.9 /s
or more on PANSS ch
Mean no. of negative symptoms rated 3 3.9 (SD = 2.3) 3.8 (SD = 2.3) 4225, n = 227) =-0.1 0.9 izo
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or more on PANSS h
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n
Comorbid diagnosis ia
b
Alcohol abuse or dependence 77% (39) 51% (93) X2(1,n = 232) = 10.2 0.001* u
Drug abuse or dependence 65% (33) 38% (68) X21,n = 232 =11.9 0.001* lletin
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Psychiatric history rtic
Had made a previous suicide attempt 55% (28) 49% (88) x20. n = 232) = 0.6 0.4 le
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Mean total length of stay in hospital (mos) 12.9 (SD = 14.7) 12.1 (SD = 20.4) 4230, n = 232) = -0.2 0.8 b
s
Mean no. of involuntary admissions 4.2 (SD = 6.1) 2.9 (SD = 3.4) 4230, n = 232) = -2.0 0.05 tra
c
Psychosocial functioning t/3
0
Mean raw score GAF scale 48.7 (SD = 14.4) 49.5 (SD = 12.6) 4223, n = 225) = 0.4 0.7 /4
Successfully completed military service 22% (11) 25% (45) x2(2, n = 230) = 0.3 0.9 /79
1
Employed at least once 86% (44) 93% (169) x20. " = 232) = 2.7 0.1 /1
9
Has had couple relationship 39% (20) 40% (73) x20. n = 232) = 0.02 0.9 31
0
7
IQ 3
Mean global IQ 89.6 (SD= 12.9) 91.8 (SD = 15.9) 4174, n= 176) = 0.7 0.5 by
g
Mean verbal IQ 86.7 (SD = 12.6) 93.4 (SD= 15.5) 4165, n= 167) = 2.2 0.03 u
e
Mean performance IQ 91.0(SD = 14.7) 89.7 (SD = 17.5) 4164, n= 166) =-0.4 0.7 st o
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Personality traits 2
6
Mean PCL-R total score 19.0 (SD = 6.7) 11.9 (SD = 7.4) 4228, n = 230)= -6.1 <0.001* N
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Mean score arrogant and deceitful v
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interpersonal behavior 2.2(SD = 2.1) 1.6(SD=1.7) 4228, n = 230) = -1.9 0.06 m
b
Mean score deficient affective experience 4.4 (SD = 2.2) 3.3 (SD = 2.2) 4228, n = 230) = -3.0 0.003 er 2
Mean score impulsive and irresponsible 0
1
behavioral style 5.7 (SD = 2.3) 4.0(SD = 2.6) 4228, n = 230) = -4.2 <0.001* 8
Symptoms before age 18 yrs
Attention/concentration problems 73% (37) 38% (68) X2(1,n = 228)= 18.6 <0.001*
Mean age of onset (yrs) 8.1 (SD = 3.6) 9.4(SD = 4.1) 481, n = 83) = 1.6 0.1
Hyperactivity 35% (18) 23% (40) X2(1,n = 228) = 3.4 0.1
Mean age of onset (yrs) 4.8 (SD = 2.9) 8.6 (SD = 4.3) 436, n = 38) = 3.2 0.003
Depressive symptoms 31% (15) 30% (53) X2(1,n = 226) = 0.01 0.9
Mean age of onset (yrs) 8.5 (SD = 4.8) 11.7 (SD = 4.4) 459, n = 61) = 2.5 0.01
795
Schizophrenia Bulletin, Vol. 30, No. 4, 2004 P. Moran and S. Hodgins
Table 1. Comparisons of the characteristics of men with schizophrenia and schizoaffective disorder with and
without comorbid APD—Continued
Variable APD No APD Test P
Substance abuse 82% (41) 41% (73) X2(1,n= 230) = 26.9 <0.001*
Mean age of onset (yrs) 13.7 (SD = 2.5) 14.9 (SD = 2.9) /(93, n = 95) = 2.0 0.05
Anxiety problems 35% (17) 34% (60) X2(1,n = 226) = 0.01 0.9
Mean age of onset (yrs) 9.8 (SD = 5.6) 9.7 (SD = 4.3) /(59, n = 61) = 0.03 0.9
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Childhood academic performance w
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Below average performance, elementary lo
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school 48% (24) 21% (36) X2(1,n= 224) = 14.8 <0.001* d
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SPulaccceeds sinfu allny icnosmtitpulteiotend b heifgohre s achgoeo 1l8 yrs 4196%% ((82)5) 4204%% ((6493)) XX22((11, ,nn == 222292)) == 191.9.7 <00..000021* d from
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Childhood victimization ttp
PPhhyyssiiccaall aabbuussee bafeteforr e1 21 2yr ysrs 7590%% ((2348)) 5386%% ((9676)) XX22((11,,nn == 222201)) == 82..22 00..1004 s://ac
a
Childhood sexual abuse 21% (10) 19% (31) X2(1,n = 214) = 0.2 0.7 de
Witnessed parental violence 23% (14) 23% (40) X2(1,n = 217) = 1.0 0.3 mic
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Paternal history u
p
Father with criminal record 18% (8) 6% (10) X2(1,n = 201) = 5.9 0.02 .c
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m
Father committed violent crime 9% (4) 1%(1) Fisher's exact test
/s
c
(n=198) 0.01 hiz
Father with substance abuse 46% (21) 31% (50) X2(1,n = 210) = 3.7 0.05 op
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re
Criminal history n
Convicted of one or more crimes 88% (45) 71% (128) X2(1, n = 232) = 6.4 0.01 iab
u
Mean age of first judgment (yrs) 17.0 (SD = 8.4) 18.7 (SD = 14.6) /(230, n = 232) = 1.1 0.3 lle
Crime before first admission to general 75% (27) 36% (40) X2(1,n= 146) = 16.3 <0.001* tin
/a
psychiatry rtic
le
Mean total no. of crimes 23.3 (SD = 30.0) 6.1 (SD = 12.53) t(230, n = 232) = -6.0 <0.001* -a
b
Mean total no. of violent crimes 5.1 (SD = 8.6) 1.9(SD = 3.0) t{230, n = 232) = 2.6 0.01 s
Mean total no. of nonviolent crimes 17.7 (SD = 26.9) 4.0 (SD = 10.6) /(230, n = 232) = 3.6 0.001* trac
At least one judgment for homicide 12% (6) 18% (32) X2(1,n = 232) = 1.0 0.3 t/3
0
/4
Note.—APD = antisocial personality disorder; GAF = Global Assessment of Functioning; PANSS = Positive and Negative Syndrome /7
Scale; PCL-R = Psychopathy Checklist-Revised; SD = standard deviation. 91
/1
* Significant association at p = 0.05 after Bonferroni correction for multiple comparisons. 9
3
1
0
7
3
b
y
model: attention/concentration problems, substance abuse, percent were characterized by all three variables; 40 per- g
u
below-average performance at elementary school, and cent were characterized by two variables; 26 percent by e
s
being placed in an institution before age 18. Likelihood one variable; and 2 percent by none of the three variables. t o
n
ratio tests indicated that the best model of childhood cor- The second model included variables that distin- 2
6
relates of APD included three variables: attention/concen- guished the participants with and without comorbid APD N
o
v
tration problems before age 18 (adjusted odds ratio: 2.83; in adulthood. The analysis included 230 participants with e
m
95% CI 1.34-5.94); substance abuse before age 18 complete data. Lifetime DSM-IV diagnoses of alcohol b
e
(adjusted odds ratio: 5.44; 95% CI 2.41-12.28); and abuse or dependence and drug abuse or dependence were r 2
0
below-average performance at elementary school entered as predictors because they had significantly distin- 18
(adjusted odds ratio: 2.91; 95% CI 1.39-6.11). This model guished the participants with and without comorbid APD
could not be improved upon to a statistically significant in univariate analyses. While the total PCL-R scores and
degree by the addition of further variables and yielded an the scores for impulsive and irresponsible behavioral style
overall likelihood ratio statistic of 46.96 (p < 0.001). The were significantly different for the participants with and
three significant variables often co-occur; therefore, we without APD, they were not entered into the model
examined the proportions of participants characterized by because they overlap with a diagnosis of APD. The score
these variables. Among the men with comorbid APD, 32 for deficient affective experience may be important in
796
Comorbid Antisocial Personality Disorder Schizophrenia Bulletin, Vol. 30, No. 4, 2004
understanding antisocial behavior among persons with bid APD, 14 percent were characterized by all five predic-
schizophrenia. It was therefore entered into the model tors, 44 percent by four, 22 percent by three, 18 percent
even though the univariate comparison was not significant by two, and 2 percent by one.
once the Bonferroni correction was applied. Site of Finally, a model was determined using variables
recruitment and hospital at discharge (forensic or general) descriptive of participants' criminal careers. The follow-
were also entered as covariates. The best model of adult ing variables were entered into this model: total number
clinical correlates of APD included three variables: adult of crimes, total number of violent crimes, total number of
alcohol abuse or dependence (adjusted odds ratio: 2.92; nonviolent crimes, having a criminal conviction before D
o
95% CI 1.38-6.15); adult drug abuse or dependence first admission to general psychiatry, site of recruitment, w
n
(adjusted odds ratio: 2.39; 95% CI 1.21^.72); and defi- and type of discharge. The best model of criminal corre- lo
a
d
cient affective experience (adjusted odds ratio: 1.25; 95% lates included only two variables: total number of crimes e
d
CI 1.07-1.46). This model could not be improved upon to (adjusted odds ratio: 1.03; 95% CI 1.01-1.05) and having fro
a statistically significant degree by the addition of any fur- a criminal conviction before first admission to general m
h
ther variables and yielded an overall likelihood ratio sta- psychiatry (adjusted odds ratio: 3.13; 95% CI 1.23-7.94). ttp
s
tistic of 27.8 (p < 0.001). Notably, among the participants ://a
with schizophrenia and co-occurring APD, 37 percent Discussion cad
were characterized by all three variables; 41 percent were e
m
characterized by two; 18 percent by one; and 4 percent by ic
Among this large sample of men with schizophrenia, .o
none of the variables. u
those with and without comorbid APD did not differ in p
.c
A final parsimonious model was determined (table 2). their mean age at onset of prodrome, mean age at onset of om
This analysis included 220 participants with complete psychosis, or levels of positive and negative symptoms at /s
c
data. The following variables were entered into this discharge. Furthermore, their history of treatment did not hiz
o
model: attention/concentration problems before age 18, differ; mean age at first admission, average number of ph
substance abuse before age 18, below-average perform- inpatient stays, and total length of all admissions were ren
ance at elementary school, DSM-IV lifetime diagnoses of similar for the two groups. These findings support results iab
u
alcohol abuse or dependence and drug abuse or depen- from previous studies (Hodgins et al. 1996, 1998; lle
dence, deficient affective experience, site of recruitment, Hodgins 2000; Tengstrom and Hodgins 2002). tin/a
and type of discharge. The most parsimonious model of While neither the schizophrenic disorder, nor timing rtic
comorbid APD included five predictor variables: sub- and length of hospital care, differed for men with and le-a
stance abuse before age 18, below-average performance at without APD, criminality did differ. Those with APD, as bs
elementary school, attention/concentration problems compared to those without, committed more nonviolent trac
before age 18, adult alcohol abuse or dependence, and criminal offenses, and significantly more of them began t/3
0
deficient affective experience. The model could not be offending before their first admission to a psychiatric /4/7
improved upon to a statistically significant degree by the ward. This finding supports results from previous studies 91
addition of further variables and yielded an overall likeli- of offenders with schizophrenia, indicating that the crimi- /19
3
hood ratio statistic of 56.2 (p < 0.001). As with the previ- nal careers of those with APD begin before first admission 10
ous multivariate models, many of the participants with to psychiatric service and involve primarily nonviolent 73
b
comorbid APD were characterized by the co-occurrence offending (Tengstrom et al. 2001; Hodgins and Janson y g
of several of these variables. Among the men with comor- 2002; Hodgins 2004). Notably, neither violent offending ue
s
t o
n
2
6
N
Table 2. Multivariate model of best predictors of comorbid APD1 ov
e
m
Variable Odds ratio (95% CI) p value be
r 2
Substance abuse before age 18 4.48(1.93-10.42) <0.001 01
8
Below-average performance at elementary school 2.85(1.33-6.11) 0.007
Attention/concentration problems before age 18 2.70(1.25-5.78) 0.01
Adult alcohol abuse or dependence 2.78(1.23-6.28) 0.01
Deficient affective experience 1.18(1.00-1.40) 0.05
Note.—APD = antisocial personality disorder; CI = confidence interval.
1 All odds ratios are adjusted for the effects of other variables in the model.
797
Schizophrenia Bulletin, Vol. 30, No. 4, 2004 P. Moran and S. Hodgins
nor homicide was found to be associated with APD. This the risk of schizophrenia (Arseneault et al. 2002; Zammit
finding is consistent with the observation that there are et al. 2002), intervening to reduce conduct disorder
several distinct subgroups of offenders with schizophrenia among children with a family history of schizophrenia
(Hodgins 2004). spectrum disorders could reduce cannabis abuse and
The men who developed comorbid APD had experi- thereby lower their risk of developing schizophrenia. The
enced numerous difficulties in childhood and early ado- effective treatment of conduct disorder during childhood
lescence. In addition to presenting conduct disorder, a sig- would reduce antisocial behaviors and increase prosocial
nificantly greater proportion of those with APD, compared skills. If schizophrenia did develop, these skills might D
o
to those without APD, presented attention/concentration serve to increase compliance with treatment and prevent w
n
problems in childhood and poor academic performance as substance misuse and crime. While the effective treatment lo
a
early as elementary school. Neither of these symptoms is of conduct disorder among children with a family history de
d
included in the diagnosis of conduct disorder. While tru- of schizophrenia would appear to have many benefits, fro
ancy from school is a symptom of conduct disorder, it is treatment for childhood attention and concentration prob- m
h
more common among teenagers than among elementary lems is potentially problematic. Stimulant medications ttp
s
school children and is not usually the cause of poor per- could theoretically alter an already fragile dopaminergic ://a
formance in elementary school. In our view, the poor system and increase the risk of later psychoses. c
a
d
early academic performance of this group is related to a Preventing the development of APD in general, and em
combination of factors, including behavior problems, specifically among persons who develop schizophrenia, is ic
.o
attention and concentration difficulties, and low verbal a goal worth striving toward. APD is almost always up
IQ. Low verbal IQ has been found to characterize children accompanied by substance abuse, and this interferes with .co
m
who develop conduct disorder (Moffitt and Caspi 2001). treatments for both schizophrenia and antisocial behavior /s
c
In addition, before the age of 18, a greater proportion of (Buhler et al. 2002; Hunt et al. 2002). Recent evidence hiz
the men with APD had spent time in an institution, had also suggests that substance abuse may lead to more op
h
been physically abused, and had fathers who had criminal severe brain damage among men with schizophrenia as re
n
careers and who abused alcohol and drugs. The signifi- compared to those without (Mathalon et al. 2003). ia
b
cance of some of these associations diminished after the The men with schizophrenia and comorbid APD ulle
Bonferroni correction was applied, perhaps as a result of obtained higher ratings on the trait of deficient affective tin
/a
insufficient sample size. However, these trends suggest experience than the men without APD. This trait has been rtic
that boys developing both schizophrenia and APD experi- found to be associated with repeated violence toward others le
-a
ence multiple problems compounded by an adverse fam- (Cooke and Michie 1997; Blair 2003). Animal research has b
s
ily situation. Given the implications of the findings from shown that the recognition of distress in potential victims tra
c
the present study, replications with larger samples and limits aggressive behavior. Individuals who obtain high t/3
0
prospectively collected data are warranted. scores for deficient affective experience are thus unre- /4
/7
Results from the present study highlight the need for strained because they fail to empathize with those they hurt. 9
1
early childhood interventions to reduce antisocial behav- While this trait is hypothesized to be the core of the syn- /1
9
3
ior and to improve academic performance, family rela- drome of psychopathy (Cooke and Michie 1997; Blair 1
0
tionships, and parenting practices for children and adoles- 2003), it may also occur in conjunction with schizophrenia. 73
b
cents at risk for schizophrenia. While interventions for The results of the present study have implications for y
g
reducing childhood conduct problems have been shown to both clinicians and researchers. Men with schizophrenia u
e
s
be effective (Scott et al. 2001), the impact on children and comorbid APD require specific interventions not only t o
n
with conduct problems who are at risk for schizophrenia to ensure compliance with treatment for schizophrenia but 2
6
is unknown. Eliminating conduct problems among chil- also to reduce antisocial behavior and substance abuse N
o
dren vulnerable for schizophrenia could prevent future and to develop prosocial skills (Hodgins and Miiller- v
e
criminality and substance misuse, provide them with Isberner 2000). Specific cognitive-behavioral programs m
b
e
skills to cope with schizophrenia if it does develop, and have been found to be effective in reducing offending and r 2
could possibly reduce the likelihood of developing schiz- increasing prosocial skills with offenders without mental 01
8
ophrenia. illness (McGuire 1995; Welsh et al. 2002). Preliminary
Conduct-disordered children are exposed to alcohol trials of such programs with offenders who have schizo-
and drugs at an earlier age than other children and go on phrenia are currently underway. Furthermore, men with
to develop more enduring and severe substance abuse schizophrenia and APD require community placements in
problems (Robins and McEvoy 1990; Armstrong and neighborhoods that support prosocial behaviors and limit
Costello 2002). In light of the recent evidence showing access to offenders, weapons, and drugs (Silver 2000). In
that heavy cannabis abuse during adolescence increases this study, we found that by the time the men with comor-
798
Comorbid Antisocial Personality Disorder Schizophrenia Bulletin, Vol. 30, No. 4, 2004
bid APD were first admitted to the general psychiatric ser- Armstrong, T, and Costello, E.J. Community studies on
vice, they had a long history of antisocial behavior, sub- adolescent substance use, abuse, or dependence and psy-
stance abuse, poor academic failure, and an adverse fam- chiatric comorbidity. Journal of Consulting and Clinical
ily environment, and many already had a criminal record. Psychology, 70:1224-1239, 2002.
There was, therefore, ample evidence for general psychi-
Arseneault, L.; Cannon, M.; Poulton, R.; Murray, R.;
atric services to identify needs for specific treatments and
Caspi, A.; and Moffitt, T.E. Cannabis use in adolescence
services in addition to those traditionally provided to first
and risk for adult psychosis: Longitudinal prospective
onset cases of schizophrenia. Ideally, such patients require D
study. British Medical Journal, 32:1212-1213, 2002. o
thorough assessments once the psychotic symptoms are w
Asarnow, J.R. Children at risk for schizophrenia: n
reduced, to identify comorbid APD. Such patients are lo
Converging lines of evidence. Schizophrenia Bulletin, a
d
likely to require complex treatment plans adapted to their e
14(4):613-631, 1988. d
antisocial personality and placement in neighborhoods fro
that support and promote positive change. Currently, gen- Blair, R.J.R. Neurobiological basis of psychopathy. m
eral psychiatric services in most Western nations do not British Journal of Psychiatry, 182:5-7, 2003. http
s
have adequate resources and time to provide such assess- Buhler, B.; Hambrecht, M.; Loffler, W.; an der Heiden, ://a
ments and services. Yet the human and financial costs of W.; and Hafner, H. Precipitation and determination of the ca
d
not providing such services are high. onset and course of schizophrenia by substance abuse: A e
m
The study has a number of strengths. To the best of retrospective and prospective study of 232 population- ic
.o
our knowledge, it is the first multicenter investigation of based first illness episodes. Schizophrenia Research, up
comorbid APD in schizophrenia. Previous studies have 54(Suppl 3):243-251, 2002. .co
m
relied on samples of patients drawn from single centers, Cannon, T.D.; Mednick, S.A.; and Parnas, J. Antecedents /s
c
thereby reducing the generalizability of their findings. of predominantly negative and predominantly positive hiz
o
Well-trained, experienced clinical raters made the assess- symptom schizophrenia in a high-risk population. p
h
ments, using standardized measures, and information on Archives of General Psychiatry, 47:622-632, 1990. re
n
childhood was obtained from multiple sources. ia
Caspi, A.; McClay, J.; Moffitt, T.E.; Mill, J.; Martin, J.; b
u
Nevertheless, the study has some weaknesses. The sample Craig, I.W.; Taylor, A.; and Poulton, R. Role of genotype lle
was weighted for criminal offending, but, based on the tin
in the cycle of violence in maltreated children. Science, /a
results of previous studies, not for APD. Given that the 297(5582):851-853, 2002. rtic
aim of the study was to identify correlates of comorbid le
Cooke, D.J., and Michie, C. An item response theory -a
APD among men with schizophrenia, the associations in b
s
our view are generalizable. The findings from the present evaluation of Hare's Psychopathy Checklist. tra
study do, however, need to be replicated, preferably in a Psychological Assessment, 9:2-13, 1997. ct/3
0
sample more representative of the population of persons Cooke, D.J., and Michie, C. Refining the construct of psy- /4
/7
with schizophrenia. Despite the expertise of the research chopathy: Toward a hierarchical model. Psychological 9
1
psychiatrists, it proved very difficult to retrospectively Assessment, 13:171-188,2001. /1
9
3
identify the age of onset of the prodrome and of psychosis. Frick, P.J.; Cornell, A.H.; Bodin, S.D.; Dane, H.E.; Barry, 1
0
By contrast, the retrospective diagnosis of conduct disor- C.T.; and Loney, B.R. Callous-unemotional traits and 73
b
der was less difficult to make, because multiple sources of developmental pathways to severe conduct problems. y g
information were used to identify externalizing problems Developmental Psychology, 39(2):246-260, 2003. ue
s
in childhood. Although we tried to reduce type I statistical Gandhi, N.; Tyrer, P.; Evans, K.; McGee, A.; Lamont, A.; t o
error in the univariate analyses by using the Bonferroni and Harrison-Read, P. A randomised controlled trial of n 2
6
correction, such "playing with p values" may be undesir- community-oriented and hospital-oriented care for dis- N
able. It implies that all outcomes have equal priority and charged psychiatric patients: Influence of personality dis- ove
therefore reduces the power to detect real differences. We m
order on police contracts. Journal of Personality b
also acknowledge the limitations of using cross-sectional Disorders, 15:94-102,2001. er 2
data to explore etiologic pathways. These data do, how- 0
1
Hare, R.D. The Hare Psychopathy Checklist-Revised: 8
ever, identify hypotheses for testing in future studies.
Manual. Toronto, Canada: Multi-Health Systems, 1991.
Heston, L.L. Psychiatric disorders in foster-home reared
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