Salford
Salford
University of Manchester
Correspondence: Dr P. Clare, Department of Child and Adolescent Psychiatry, Booth Hall Hospital, Charlestown Road, Blackley, Manchester M97AA
![]() |
ABSTRACT |
---|
![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() |
---|
Aims To investigate the possible relationships between criminally violent types of behaviour, and psychopathology and social factors, among adolescents suffering from a psychotic disorder.
Method A retrospective case note study of 39 in-patients diagnosed as having a psychotic disorder and admitted to one of two adolescent psychiatry units (one secure, one open). Cases were divided into a violent and a non-violent group, and these two groups were then compared for social and psychopathological variables.
Results There was no association between recorded psychopathology and criminally violent behaviour. Criminally violent behaviour was associated with a history of emotional or physical abuse, contact with social or mental health services, and previous criminal behaviour.
Conclusions These findings fail to echo results of studies in adult schizophrenia; they suggest that violent behaviour in psychosis is associated more closely with social factors than with specific symptoms of the psychotic illness. Potential explanations are discussed.
![]() |
INTRODUCTION |
---|
![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() |
---|
![]() |
LITERATURE REVIEW |
---|
![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() |
---|
Studies to investigate associations between violence and psychosis have ranged from comparing criminal populations (Häfner & Böker, 1973) to twin studies (Coid et al, 1993), and have in general demonstrated that individuals suffering from schizophrenia display an increased rate of violence.
Longitudinal studies in Sweden and the UK have drawn broadly similar conclusions: that women with schizophrenia are more likely to be convicted of a criminal offence than women in the general population, but that the increased rate of crime in male schizophrenia sufferers is accounted for by an increase in violent offences (Lindqvist & Allebeck, 1990; Wessely et al, 1994). Wessely et al conclude that "the strongest associations of criminal conviction remain those recognised in non-schizophrenic subjects".
Any link between violence in psychosis and psychophenomenology remains difficult to study effectively. In a subgroup of male remand prisoners with psychoses, 20% appeared directly driven to offend by their psychotic delusions, and a further 26% were probably driven to, although 93% had shown symptoms at the time of their offence (Taylor, 1985). Data from the Epidemiological Catchment Area study, re-examined by Swanson et al (1996), suggested that psychotic symptoms related to threat/control override (TCO) (delusions of passivity, persecution, poisoning, pursuit or possession of thought) were most strongly linked to violent types of behaviour. Interestingly, TCO symptoms appeared to predict violence even in the absence of major psychiatric disorder in the previous year, although they were more predictive in the presence of major psychiatric disorder and even more so with the additional effect of substance misuse. Reviewing the literature on auditory hallucinations and acts of violence, McNeil (1994) concluded that most patients do not comply with their command hallucinations, although this is questioned by Sheldrick (1999). More recently, Cheung et al (1997) suggested an association of violence with differences in the tone, content and emotional impact of the hallucinations, and also with persecutory delusions, symptoms suggesting frontal lobe impairment, a history of aggression, and with abnormal personality traits.
Studies on adolescence
We have identified only one published study, from America, which
specifically examines the relationship between violent behaviours and
psychosis in adolescents (Inamdar et
al, 1982). The authors discuss the possible impact of
adolescent developmental crises and how sociocultural factors may mediate the
expression of both violence and psychosis. Developmental aspects of violence,
criminality and illness are critical considerations, as has been nicely
illustrated by Taylor and Parrott
(1988) at the other end of the
developmental spectrum, the elderly. Inamdar et al
(1982) found a much higher
incidence of violence in hospitalised adolescents with psychosis (66.7%) than
in their cited adult sample (8%).
There has been more research in the field of violence in adolescence unrelated to psychosis. Reviewing both prospective and retrospective research, Boswell (1997) suggests that victimisation and loss at an early age have consequences for future violent behaviour, and cites the particular association of physical abuse with violence. Stiffman et al (1996), in their US longitudinal study, found that a combination of personal variables (gender, substance misuse) and environmental variables (history of child abuse, stressful and traumatic events, rates of unemployment) predicted almost a third of the variance in adolescent violent behaviour.
Summary of previous findings
The above studies suggest a complex relationship between psychosis and
violent offending in adults. Many of the variables that show association with
violence within a psychosis group would also predict violence in a
non-psychosis group. Studies of violence in adolescence reveal a variety of
associations to variables related to the adolescent's background, but there is
little known about psychosis and violence in adolescence.
![]() |
METHOD |
---|
![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() |
---|
Case definition and data collection
A single researcher (P.C.) collected the data from case notes, including
correspondence, medical and nursing entries. All case notes from January 1990
to July 1998 in which the case note discharge diagnosis was of schizophrenia
or of another psychotic disorder (ICD-10 codes of F20.9, F30.2, F31.2, F32.2
or equivalent ICD-9 codes) were included within the study
(World Health Organization,
1992). Cases with a diagnosis of a drug-induced psychosis only
were not included. No attempt was made to review the diagnosis on the basis of
the information in the notes, and the broader category of psychosis was used,
as there is a marked diagnostic instability within the psychoses in the
adolescent age range (McClellan et
al, 1993). Low numbers would also preclude separate analysis
by diagnosis. Data relating to history of violent criminal behaviour (defined
as violent behaviour followed by formal caution or criminal proceedings) and a
range of epidemiological, developmental and psychopathological factors were
extracted onto a proforma (available from P.C. upon request). Examples of
violent criminal behaviour included murder, attempted murder and armed
robbery. Symptoms were recorded as present if documented in the case notes,
irrespective of their apparent temporal relationship to any violent incidents.
When notes did not contain information on a particular variable, it was
recorded as missing. An exception was data on ethnic group, where information
was collected from staff on what ethnic group (White, Black, Asian) the young
people considered themselves to belong to; this was only used if there was
agreement from two independent sources.
Hypotheses
Hypothesis 1 was that occurrence of violent behaviour would be associated
with specific psychopathology (command hallucination, persecutory delusion);
and Hypothesis 2, that it would be associated with specific social factors
(abuse, criminality, disrupted parenting).
Analysis
Most of the data were in categorical form. The results were analysed using
SPSS for Windows (version 8.0), making comparisons, according to the
hypotheses, between the violent and non-violent
groups. Fisher's exact tests were used in every instance, as numbers were
small. Two-sided tests were used on each occasion, as the association would
have been of interest whether it went with the null hypothesis or against. In
accordance with contemporary statistical practice, no adjustments for making
multiple comparisons were made (Rothman,
1990; Perneger,
1998). The value of P <0.05 was used to indicate
statistical significance.
![]() |
RESULTS |
---|
![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() |
---|
Comparisons between the violent and non-violent groups
Table 1 confirms that
histories of experiencing either physical or emotional abuse appear to
distinguish criminally violent from non-violent adolescents with psychosis. A
history of experiencing sexual abuse shows no significant association, but
numbers were very small in both groups. The finding of an association between
a history of local authority care and criminal violence is somewhat weakened
by the fact that some of the youngsters in the violent group
found themselves in secure care as a result of their violent behaviour. Low
numbers, however, preclude further statistical examination of this (e.g. by
regression analysis). A previous criminal history appears as the strongest
association with criminal violence. Most of the violent group had previous
contact with social services (86%), and with psychiatry (64%), in contrast
with the non-violent group.
|
Table 2 shows that none of the psychopathological variables discriminated between the violent and non-violent groups. Indeed, looking at the figures, the prevalence of discrete psychopathology appears remarkably similar. A finding not predicted in the hypothesis is the association with response to medication, which appears to suggest a better-perceived response to medication in the non-violent group.
|
![]() |
DISCUSSION |
---|
![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() |
---|
It is important to be clear which questions this study is able to address. It does not answer the question, "Is violence more common in adolescents with psychotic disorder than those without?". Neither can it address issues of causality, which would require a prospective and longitudinal approach rather than the retrospective and cross-sectional one here. It does however attempt to tease out which factors, in those individuals with both psychosis and criminal violence coexisting, might be related to their coexistence.
Hypothesis I: comparing across psychopathological variables
The study demonstrated no associations between a history of violent
criminal behaviour and the psychopathological variables recorded. The study
was designed to look at the individual's propensity to criminal violence,
rather than violence occurring specifically within a psychotic episode. The
above finding could possibly be explained by the inference that the criminal
violence committed by these youngsters was unrelated to their psychotic
illness. This potential inference is important, as sentencing and admission
decisions may be based upon an assumption that the violent behaviour is
related to the psychotic disorder. Adult studies tend to support the latter
assumption. None of this negates the need for secure psychiatric care for this
age group, where the violence and psychosis can be simultaneously managed.
There is a possibility that the numbers in the study were insufficient to show any association that does exist. However, none of the psychopathological variables even showed a trend towards significance in the comparison, and a look at the raw numbers gives no indication of the existence of a possible undetected association. A further possibility was that an association exists, but that the recorded psychopathology was too limited to demonstrate it. Studies in adults suggest that more sophisticated recording of psychopathology, for example using the Maudsley Assessment of Delusions Schedule (Taylor et al, 1994) and recording emotional quality to the tone and content of hallucinations, is required in order to see associations with violence (Cheung et al, 1997). Additionally, it may not be an individual symptom that is important but rather the coexistence of specific combinations (Swanson et al, 1996; Sheldrick, 1999). This may be particularly relevant where the attack is apparently motiveless. We did not have the information to pick out such a subgroup.
The failure of the study to demonstrate any statistical relationship between criminal violence and aspects of psychopathology does not refute the basic premise, derived from adult studies, that violence and psychosis are somehow linked. It is important to reiterate that youngsters behaving violently who are not cautioned or charged or even identified will not fall into the violent group here, and we must keep in mind exactly the population being studied. The apparent demonstration of an association of criminal violence with social factors does not mean that they are the sole determinants of such violent types of behaviour. Rather, it points to a more complex relationship, requiring further exploration of combinations of factors acting in concert rather than in isolation for this developmental group.
Hypothesis 2: comparing across family and background variables
A history of physical abuse and emotional abuse each appeared to be
significantly associated with a history of criminal violence within this
population. Interestingly, sexual abuse did not show the same association,
although this may reflect underreporting. Family variables potentially related
to such abuse (paternal or maternal history of violence, alcoholism, or mental
illness) did not show the same association, although there was missing data in
these categories.
A previous criminal history was strongly associated with criminal violence. Much of the previous offending was of a non-violent nature, and this again broadly fits with the findings of some adult studies (Häfner & Böker, 1973; Wessely et al, 1994). There was a significant association between criminal violence and being known to social or mental health services. In their preliminary report of the Edinburgh High Risk Study, Hodges et al (1999) suggest that there may be a subgroup in whom offending behaviour types might be a prodromal indicator of psychotic illness. With increasing interest and work on early detection and intervention in schizophrenia (McGlashan, 1998), and taking into consideration ideas on the management of adolescent violence, this raises the possibility of earlier intervention.
Other findings
Two interesting findings unrelated to the initial hypotheses were the
differences in length of in-patient stay and response to treatment between the
two groups. Clearly some interaction between these two variables is likely.
The non-violent youngsters with psychosis had a broadly similar
length of stay on whichever unit, while the violent group had a
longer average stay. Those in the latter group were also significantly more
likely to show a poor, or variable, response to treatment recorded. This
association was not present between the units when the violent
group was removed from the analysis. It is not possible to infer from this
whether the violent group are experiencing a more severe form of psychosis,
whether their violence is directly affecting their treatment, or whether their
differing backgrounds somehow predispose them to responding more slowly (e.g.
poorer compliance, greater psychological arousal, less social support).
The issue of ethnic group raises some interesting questions. Adult studies have suggested that African-Caribbean patients with schizophrenia are more likely to be detained (McGovern & Cope, 1987). The Black ethnic group was overrepresented in the violent group, which might have reached statistical significance in a larger sample. When comparisons were made across the units without the violent group, the Black group was not overrepresented on the secure unit. Our criterion for inclusion within the violent group is dependent on police having taken action, and the possible influence of institutional racism must be borne in mind.
Clinical implications
This is the first study to investigate the association between adolescent
psychosis and criminally violent behaviour. Despite its inherent flaws, it
gives a description of some of the characteristics of adolescents with
psychosis who have a history of criminally violent behaviour, a group which is
the subject of considerable social and medical concern. For many of the
youngsters, this behaviour has been very destructive and has often led to
their incarceration. Since in a number of cases in this study, the act of
violent behaviour was murder or attempted murder, it would be very valuable if
we could increase our ability to identify this group before the violent event
occurred. The study makes a start by discussing the very difficult art of risk
assessment in this age group (Sheldrick,
1999), although the apparent lack of specific associations with
aspects of psychopathology is surprising, and at variance both with practice
and with much of the adult literature. Criminally violent adolescents
suffering from psychosis appear from this study to be more likely to be in
contact with services prior to the event that may lead to their incarceration
than do non-violent adolescent sufferers. These two findings emphasise the
need for co-operation and collaboration between agencies, within the
frameworks of both a Care Programme Approach and the principles of the
Children Act 1989.
Recommendations for future research
The best way of answering some of the questions that this study raises
would be a prospective longitudinal study of psychosis in adolescence,
recruiting every incident case within a defined geographical area and having a
general population control group for comparison purposes. Recording of
psychopathology should be more sophisticated. A more complete history of acts
of violence as well as criminal behaviour, with careful recording of events
surrounding these, would be desirable. Formal psychometry, assessing
personality traits and frontal lobe impairment, should be included. Further
investigation of lifestyle and of social and cultural influences, including
those related to ethnic group, should not be neglected. Low numbers, problems
of ascertainment and issues of compliance are all likely to militate against
this. None the less there is value in having a clinical and needs-based
perspective in addition to that derived from epidemiological and
criminological approaches. Perhaps more feasibly, a longitudinal study at a
single service such as the Adolescent Forensic Service could partially answer
some of the questions raised here, despite its selected sample and the small
numbers involved, particularly if compared to a matched group of violent
adolescents without psychosis.
![]() |
Clinical Implications and Limitations |
---|
![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() |
---|
LIMITATIONS
![]() |
REFERENCES |
---|
![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() |
---|
Cheung, P., Schweitzer, L., Crowley, K., et al (1997) Violence in schizophrenia: role of hallucinations and delusions. Schizophrenia Research, 26, 181-190.[CrossRef][Medline]
Citrome, L. & Volavka, J. (1999) Schizophrenia: violence and comorbidity. Current Opinion in Psychiatry, 12, 47-51.[CrossRef]
Clark, A. F. & Lewis, S. W. (1998) Practitioner review: treatment of schizophrenia in childhood and adolescence. Journal of Child Psychology and Psychiatry, 39, 1071-1081.[CrossRef]
Coid, B., Lewis, S. W. & Reveley, A. M. (1993) A twin study of psychosis and criminality. British Journal of Psychiatry, 162, 87-92.[Abstract]
Häfner, H. & Böker, W. (1973) Mentally disordered violent offenders. Social Psychiatry, 8, 220-229.
Hodges, A., Byrne, M., Grant, E., et al (1999) People at risk of schizophrenia. Sample characteristics of the first 100 cases in the Edinburgh High-Risk Study. British Journal of Psychiatry, 174, 547-553.[Abstract]
Inamdar, S. C., Lewis, D. O., Siomopoulos, G., et al (1982) Violent and suicidal behaviour in psychotic adolescents. American Journal of Psychiatry, 139, 932-935.[Medline]
Lindqvist, P. & Allebeck, P. (1990) Schizophrenia and crime. A longitudinal follow-up of 644 schizophrenics in Stockholm. British Journal of Psychiatry, 157, 345-350.[Abstract]
McClellan, J. M., Werry, J. S. & Ham, M. (1993) A follow-up study of early onset psychosis: comparison between outcome diagnoses of schizophrenia, mood disorders and personality disorders. Journal of Autism & Development Disorders, 23, 243-262.
McGlashan, T. (1998) Early detection and intervention of schizophrenia: rationale and research. British Journal of Psychiatry, 172 (suppl. 33), 3-6.
McGovern, D. & Cope, R. (1987) The compulsory detention of males of different ethnic groups, with special reference to offender patients. British Journal of Psychiatry, 150, 505-512.[Abstract]
McNeil, D. E. (1994) Hallucinations and violence. In Violence and Mental Disorder: Developments in Risk Assessment (eds J. Monahan & J. Steadman), pp. 183-202. London: University of Chicago Press.
Perneger, T. V. (1998) What's wrong with
Bonferroni adjustments? British Medical Journal,
316,
1236-1238.
Rothman, K. J. (1990) No adjustments are needed for multiple comparisons. Epidemiology, 1, 43-50.[Medline]
Sheldrick, C. (1999) Practitioner review: the assessment and management of risk in adolescents. Journal of Child Psychology and Psychiatry, 40, 507-518.[CrossRef]
Stiffman, A. R., Dore, P. & Cunningham, R. M. (1996) Violent behaviour in adolescents and young adults: a person and environmental model. Journal of Child and Family Studies, 5, 487-450.
Swanson, J. W., Borum, R., Swartz, M. S., et al (1996) Psychotic symptoms and disorders and the risk of violent behaviour in the community. Criminal Behaviour and Mental Health, 6, 309-329.
Taylor, P. J. (1985) Motives for offending among violent and psychotic men. British Journal of Psychiatry, 147, 491-498.[Abstract]
Taylor, P. J. & Parrott, J. M. (1988) Elderly offenders. A study of age-related factors among custodially remanded prisoners. British Journal of Psychiatry, 152, 340-346.[Abstract]
Taylor, P. J., Garety, P., Buchanan, A., et al (1994) Delusions and violence. In Violence and Mental Disorder: Developments in Risk Assessment (eds J. Monahan & J. Steadman), pp. 183-202. London: University of Chicago Press.
Wessley, S. C., Castle, D., Douglas, A. G., et al (1994) The criminal careers of incident cases of schizophrenia. Psychological Medicine, 24, 483-502.[Medline]
World Health Organization (1992) The ICD-10 Classification of Mental and Behavioural Disorders. Geneva: World Health Organization.
Received for publication July 27, 1999. Revision received December 15, 1999. Accepted for publication March 3, 2000.