Mental Health Group, Department of Psychiatry, The University of Southampton, Southampton
Institute of General Practice and Primary Care, School of Health and Related Research, The University of Sheffield, Sheffield, UK
Correspondence: Dr Elizabeth A. King, Mental Health Group, University Department of Psychiatry, RSH Hospital, Brinton's Terrace, Southampton SO14 0YG, UK. E-mail:eak{at}soton.ac.uk
Declaration of interest This study was funded by the NHS South & West Research and Development Directorate.
See part 1, pp.
531536, this issue.
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ABSTRACT |
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Aims To compare social, clinical and health-care delivery factors in in-patient and out-patient suicides and their controls.
Method Retrospective casecontrol study of 59 in-patients and 106 controls, matched for age, gender, diagnosis and admission date. Odds ratios were calculated using conditional multiple logistic regression.
Results There were seven independent increased-risk factors: history of deliberate self-harm, admission under the Mental Health Act, involvement of the police in admission, depressive symptoms, violence towards property, going absent without leave and a significant care professional being on leave. When compared with out-patient suicides, in-patients were more often female and male in-patients had a psychotic illness. Unlike the out-patient suicides, social factors were not found to be significant.
Conclusions The characteristics of in-patient and out-patient suicides differ. Identified risk factors have relatively low sensitivity and specificity.
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INTRODUCTION |
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METHOD |
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Identification of cases
The 373 patients who died by suicide within a year of their final hospital
admission formed the overall patient group; 75 of these died while in
hospital. The cases in this study were the 59 in-patients (79%) for whom case
notes could be found. In-patient suicides who died in hospitals outside Wessex
were excluded owing to the difficulties in obtaining ethical approval to
inspect the notes of these individual patients.
Matching with control patients
Each index patient was matched with two controls using the following
sequential criteria: gender, age, diagnostic group, ward type and admission
date. Every index patient was matched with at least one control.
Data collection
One of us (J.M.A.S.) extracted demographic, clinical and health-care data
from medical case notes onto the specifically designed study pro forma, with
additional data (e.g. legal status and observation level) noted for index
patients. When not recorded in the case notes, some further information
relating to the circumstances of death (e.g. time of day, place and method of
death) was derived from coroners' records, obtained as part of an ongoing
audit of suicides in Wessex.
Statistical procedures
We performed univariate and multiple regression analyses using conditional
logistic regression (Collett,
1991) in STATA 6 (StataCorp,
1999). We identified 60 potential variables for the in-patient
deaths and 105 variables for the out-patient deaths, as already described.
Stepwise backward elimination of variables, with probability for rejection set
at 0.1, was used to produce a parsimonious model. Non-conditional logistic
regression was used in separate comparisons of in-patient and out-patient
suicides and their controls.
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RESULTS |
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The only pre-admission factor that differentiated index patients from controls was a history of deliberate self-harm (Table 1). There was no significant difference between the cases and controls in length of illness, number of previous admissions or family history of either mental illness or suicide.
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Admission variables
Of the 59 cases, 37 (63%) had been admitted to old mental
hospitals, 21 to district general hospital psychiatric units and 1 to a
private hospital. Sixteen (27%) in-patient deaths occurred within the first
week of admission, 32 (54%) between 1 week and 3 months, 7 (12%) after 3
months and 4 (7%) after more than 1 year.
Gender differences between index patients
The male/female in-patient suicide ratio was 1.2:1. Significantly more
males (13, 40.6%) than females (2, 7.4%) suffered from schizophrenia or a
schizophrenia-like illness (Table
2). A lifetime history of deliberate self-harm was present in 25
females (92.6%) and 17 males (53.1%).
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Circumstances of death
Legal status of in-patient suicides
At the time of the event leading to death, 12 patients (22.3%) were
detained under the Mental Health Act 1983, 46 (78%) were informal and 1
patient was on Section 17 leave from hospital.
Observation status
Fifteen (25.4%) patients were on leave from hospital at the time of their
death. Of those not on leave, 20 (45%) were subject to regular checks and 18
(41%) were subject to low-level routine or general observations. There was no
record of observation status for six patients (14%). Discharge plans were
being made for 22% of the in-patient deaths. Only 44% of the patients were
granted leave during the index admission, compared with 60% of controls. Of
those who were granted leave, 35% of patients but only 5% of controls were
recalled or returned earlier than planned.
Noted suicide risk at last contact
There was no significant difference between patients and controls in the
suicide risk noted at admission. No record of suicide risk was made at last
contact with a staff member in 28 cases (47.5%). Risk factors for suicide were
noted in 23 cases (39%). For eight patients in whom the risk was both noted
and quantified, the risk of suicide was considered low in five and high in
three patients.
Time of death
The time of death for four patients was uncertain. Of those who died on
hospital premises, 19 deaths (73%) occurred on a weekday and 7 at the weekend.
About half of these 26 deaths occurred during the day (42% during weekdays and
57% at the weekend) and one-third during the evening or at night. There was no
significant difference between the number of deaths in weekday (49%) and
weekend periods (44%).
Location
Twenty-three patients (39.0%) died on the ward or elsewhere in the hospital
building and four (6.8%) died within hospital grounds. Thirty-two patients
(54%) had left the hospital grounds before the event leading to their death
(17 were either on leave or out with permission but 15 had not been granted
leave): 12 patients died at home, 1 died on a boat and 19 died elsewhere.
Cause of death
Information from inquest files indicated that hanging was the most common
cause of death among in-patients of either gender, accounting for 41% of male
and 44% of female deaths. Twelve of the 16 men and 7 of the 10 women hanged
themselves in the ward area. Thirty per cent of females but only six per cent
of males died from a drug overdose. Currently prescribed drugs were not used
by any of the five patients who took fatal overdoses while in the ward. Half
of the drug overdoses were taken away from the ward. Of the 19 patients (32%)
who died away from hospital premises, 8 men and 2 women were killed by trains
or other moving vehicles.
Contact with others after death
Relatives were telephoned after the death of 36 patients (61.1%); in 24
instances the telephone call was followed by face-to-face contact. The
relatives of 4 suicides (6.8%) were contacted face-to-face. In 19 patients
(32.2%) there was no record of contact with relatives; for 4 of these, contact
was made with the patient's general practitioner.
Differences between in-patient and out-patient suicides
Relatively more of the in-patient suicides were women (male/female ratio
1.2:1). The diagnostic distribution is shown in
Table 2. In both in-patient and
out-patient suicides the majority of patients with schizophrenia and
schizophrenia-like disorders were male. Psychotic and nonpsychotic affective
disorders were present in a similar proportion of in-patient and out-patient
suicides.
Comparison between in-patient suicides and matched controls
Table 3 summarises the 18
variables with a P value of <0.20 in the univariate model and the
results of the multiple regression used to produce a parsimonious model. The
seven independent variables associated with an increased risk of suicide that
remained in the model after backward elimination of variables (with
probability for rejection set at 0.1) are shown in
Table 4.
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Number of risk factors
Significantly more patients (30, 51%) than controls (12, 11.3%) had three
or more of the seven risk factors (Table
5). No social factors were found to discriminate between patients
and controls. Admission under the Mental Health Act and depressive symptoms
elicited on admission were independently associated with increased risk of
suicide.
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Events during admission
A display of violence to property and going absent without leave (AWOL)
were both associated with suicide, as was a significant professional leaving
employment or going on leave.
Comparison between in-patient and out-patient suicides and
controls
Index patients
Admission under the Mental Health Act, going absent without leave or
showing violence to property during the final admission occurred significantly
more frequently in in-patient than out-patient cases
(Table 6).
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There was no significant difference between in-patient and out-patient suicides in the presence of depressive symptoms at admission (76.3% v. 71.4%) or the absence of a significant health-care professional at the time of the event leading to death (2.8% v. 0.9%). The social factors associated with an altered risk of suicide following discharge do not appear to affect the risk of in-patient suicide (King et al, 2001) (Table 7).
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Controls
In-patient controls and out-patient controls did not differ in any of these
variables.
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DISCUSSION |
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Study limitations
As described in the accompanying paper
(King et al, 2001),
this study has three limitations. The first is the reliance on data collected
retrospectively from case notes not intended for research purposes. The second
is that the data collection was not performed blind to patient outcome. The
final limitation is that many variables were analysed, although these were
identified as potential factors a priori, with correction for
multiple variables.
Study strengths
However, the study design has several advantages. First, data were
collected using a standardised instrument, with operationally defined
criteria. The patients were identified through the long-running Wessex Suicide
Audit with ready access to coroners' records. Because of its size, data could
be limited to a period of 8 years, in contrast to a recent study in which data
were derived from admissions over a 30-year period
(Powell et al,
2000).
Comparison with previous investigations
The in-patient suicides in this study are similar to those in previous
cohorts, irrespective of country, including New Zealand
(Read et al, 1993),
Australia (Shah & Ganesvaran,
1997), Canada (Proulx et
al, 1997) and Ireland
(Coakley et al, 1996).
There are similarities in the proportion of patients with psychotic illnesses,
particularly schizophrenia (Modestin &
Hoffmann, 1989; Coakley et
al, 1996; Proulx et
al, 1997; Shah &
Ganesvaran, 1997), and in those with a history of deliberate
self-harm or requiring compulsory admission
(Read et al, 1993).
Furthermore, there are similarities in deaths from hanging or associated with
moving vehicles, and in the prevalence of deaths occurring away from the ward
(Proulx et al, 1997;
Shah & Ganesvaran, 1997). As such, the findings of this study may be widely applicable.
Comparison with out-patient suicides
There is a relative excess of female in-patient suicides, the male/female
ratio being 1.2:1, similar to that found in other studies
(Proulx et al, 1997;
Powell et al, 2000).
Certain risk factors for suicide in in-patients, such as admission under the
Mental Health Act, involvement of police, violence towards property and going
absent without leave, may reflect greater turmoil than is seen in those
patients who kill themselves after discharge. Social factors appear relatively
more important in out-patient suicides.
Implications for clinical practice
Six of the seven identified risk factors for in-patient suicide are
patient-related. Four of these are factors generally recorded on admission
(being admitted under the Mental Health Act, or after involvement with police,
the presence of depressive symptoms and a history of deliberate self-harm).
The other two, namely display of violence to property and going absent without
leave, were recorded during admission.
The six patient-related factors are easily recorded, either as part of the standard admission procedure or in routine ward observations. Some factors are common, such as the presence of depressive symptoms, but others occur less often, for example being admitted under the Mental Health Act and/or via the police. Violence to property and being AWOL are relatively infrequent. When health professionals are about to go on leave it may be advisable to make careful arrangements for continuity of care, particularly if other risk factors are present.
Self-poisoning represents a much lower proportion of in-patient than out-patient suicides. Because none of the in-patients who died from a fatal overdose used currently prescribed medication, this suggests that restricting access to potentially fatal means can reduce the number of drug-related deaths. Restricting the means of self-hanging is more difficult, but optimising the ward environment and patient observation has the potential to make some impact on in-patient deaths.
There was no difference in recorded suicide risk in either patients or controls at admission, but in almost half of the cases no statement of risk had been recorded by staff at their last contact with the patient. Continuing the risk assessment process throughout hospital care may allow potential risk and protective factors to be identified. Although the odds ratios for risk factors are high, they occur in only a minority of patients and thus the sensitivity of individual risk factors is low.
The risk of suicide is present in many psychiatric in-patients. Although the ability to predict suicide accurately is limited, the conscientious and continuing assessment of individual risk and thoughtful policies and procedures may prevent some fatal outcomes (Sederer, 1994).
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Clinical Implications and Limitations |
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LIMITATIONS
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ACKNOWLEDGMENTS |
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REFERENCES |
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Appleby, L., Shaw, J., Amos, T., et al
(1999b) Suicide within 12 months of contact with
mental health services: national clinical survey. British Medical
Journal, 318,
1235-1239.
Coakley, G. M., Carey, T. G. & Owens, J. M. (1996) A study of psychiatric inpatient suicides. Irish Journal of Psychological Medicine, 13, 102-104.
Collett, D. (1991) Modelling Binary Data. London: Chapman & Hall.
King, E. A., Baldwin, D. S., Sinclair, J. M. A., et al
(2001) The Wessex Recent In-Patient Suicide Study, 1.
Casecontrol study of 234 recently discharged psychiatric patient
suicides. British Journal of Psychiatry,
178,
531-536.
Modestin, J. & Hoffmann, H. (1989) Completed suicide in psychiatric inpatients and former inpatients. A comparative study. Acta Psychiatrica Scandinavica, 79, 229-234.[Medline]
Pirkis, J. & Burgess, P. (1998) Suicides and recency of health care contacts. A systematic review. British Journal of Psychiatry, 173, 462-474.[Abstract]
Powell, J., Geddes, J., Deeks, J., et al
(2000) Suicide in psychiatric hospital in-patients. Risk
factors and their predictive power. British Journal of
Psychiatry, 176,
266-272.
Proulx, F., Lesage, A. D. & Grunberg, F. (1997) One hundred in-patient suicides. British Journal of Psychiatry, 171, 247-250.[Abstract]
Read, D. A., Thomas, C. S. & Mellsop, G. W. (1993) Suicide among psychiatric in-patients in the Wellington region. Australian and New Zealand Journal of Psychiatry, 27, 392-398.[Medline]
Sederer, L. I. (1994) Managing suicidal inpatients. Death Studies, 18, 471-482.[Medline]
Shah, A. K. & Ganesvaran, T. (1997) Inpatient suicides in an Australian mental hospital. Australian and New Zealand Journal of Psychiatry, 31, 291-298.[Medline]
StataCorp (1999) Statistical Software: Release 6.0. College Station, TX: Stata Corporation.
Received for publication May 2, 2000. Revision received December 11, 2000. Accepted for publication December 15, 2000.
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