Liverpool University
Northern Birmingham Mental Health Trust
Correspondence: Emad Salib, Consultant Psychiatrist, Hollins Park Hospital, Warrington WA2 8WA, UK
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ABSTRACT |
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Aims To explore variations in postmortem brain weight in different methods of fatal self-harm (FSH) and in deaths from natural causes.
Method A review of a sample of coroners' records of elderly persons (60 and above). Verdicts of suicide, misadventure and open verdicts were classified as FSH. Post-mortem brain weight for 142 FSH victims and 150 victims of unexpected, sudden or unexplained death due to natural causes, and from various methods of FSH, were compared.
Results Brain weight of victims of FSH was significantly higher than of those who died of natural causes (P <0.01); brain weights in both groups were within the normal range for this age group. There was no significant difference in brain weight between different methods of FSH (P >0.05).
Conclusions The findings require critical examination and further research, to include data from younger age groups. A regional or national suicide neuropathological database could be set up if all victims of FSH underwent routine neurohistochemical post-mortem examination.
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INTRODUCTION |
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We found only one published article about the effect of various methods of fatal self-harm (FSH) on brain weight. Schroder and Saternus (1983), investigating changes in the brain caused by suicidal hanging, found that the brain weight - both for typical and atypical hanging - was greater in all age groups than the average found in clinical autopsy. Investigating the effect of hypothalamic-pituitary-adrenal dysfunction in major depression and suicidal behaviour, Szigethy et al (1994) found that the mean left adrenal weight was significantly higher in suicide victims, but these authors did not comment on brain weight.
In this study we attempt to explore whether brain weight measured postmortem varies with different methods of FSH and whether it differs from that of persons who died of natural causes.
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METHOD |
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Fatal self-harm data
Data were extracted from coroners' records of all deaths of persons aged 60
years or over from 1994 to 1998 occurring within the North Cheshire and
Birmingham districts, for those classified as having committed suicide (ICD-9
E950-959), and for those for whom an open verdict or a verdict of misadventure
was returned (ICD-9 E980-989; World Health
Organization, 1978), from two Coroner's Offices, in Warrington
(35% of the sample) and Birmingham (65%). Information extracted included
demographic data, method of death and coroner's verdict, and brain weight as
recorded by the pathologist. The brain weights of people aged 60 whose
deaths were unexpected, sudden or unexplained (thus requiring a post-mortem),
but attributed to natural causes, were also collected for comparison.
Unfortunately, data relating to body weight and height were not available. The
deceased were matched by obtaining equal means and variances of the two groups
for age by gender. For all subjects, whether death was due to natural causes
or FSH, post-mortem examination was reported to have been carried out within
6-12 hours of death. All brain weights included in the study were reported as
wet autopsy weights where no formalin fixation was used.
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RESULTS |
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Of the methods of fatal self harm, 39% were overdose, 24% hanging, 9% drowning, 16% asphyxia or inhalation of carbon monoxide and 12% were other means (mostly violent). The natural causes of deaths were cardiac or cardiovascular (80%), respiratory (15%) and cerebral haemorrhage (5%). The mean brain weight for the entire sample was 1291 g (s.d.=124) (median 1280) (males, 1310 g (s.d.=122); females, 1258 g (s.d.=119)). Table 1 gives the basic statistics.
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Figure 1 is a box plot graph of the highest and lowest brain weights; the median is a thick line inside each box, which contains 50% of cases within the interquartile range. The central position of the median indicates a normal distribution of weights, with positively skewed distribution in some FSH methods involving small numbers.
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Table 2 summarises the distribution of brain weight in FSH cases in relation to the method of death. A suicide verdict appears to have been returned more frequently in cases of FSH by hanging and asphyxia using a plastic bag; but a suicide verdict was also returned in all incidents of FSH by wounding, electrocution and carbon monoxide poisoning using car exhaust. An open verdict was returned more frequently in cases of death by drowning, being killed by a train, jumping from a height and setting fire to oneself. Electrocution, car exhaust and setting fire to oneself were methods used only by men.
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Means of brain weight were compared using the t-test for the following groups:
Comparison of the means seems to suggest that the brain weight of deceased elderly cases of suicide or an open verdict after FSH was significantly higher than that of those who died naturally. There was no significant difference in brain weight between the two groups, indicating that open verdict and suicide cases belong to the same population within the FSH group.
Nor was there any significant difference between mean brain weights for all methods of death in the FSH group (ANOVA P>0.05), nor any significant variations in brain weight with cause of death within the comparison group (cardiac, cardiovascular or respiratory causes). The brain weights of all those who had died naturally or fatally harmed themselves were nevertheless within the expected normal range for this age group.
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DISCUSSION |
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Interpretation of the findings
Brain weights vary with age, gender, cause and mode of death and what
happened to the brains after death (Knight,
1996). The brain is usually examined immediately (wet
cutting) or is suspended in formalin until fixed, a process which takes
several weeks. In the majority of autopsies there is no real need for fixation
if no cerebral lesions are suspected, expected or apparent on external
examination (Knight, 1996). In
this study all brain weights were reported as wet autopsy
weights where no formalin fixation was used, so increased weight cannot be
attributed to the fixation process.
The increase in brain weight in association with histological signs of oedema in hanging was put down to a definite terminal post-mortem brain swelling, as it is known in all forms of peracute death caused by unrestricted arterial flow but reduced venous return from intracranial sinuses (Schröder & Saternus, 1983). Cerebral oedema can be caused by hypoxia, intracranially due to direct or indirect trauma, or from any part of the body, and, whether traumatic or hypoxic, the cerebral oedema is self-potentiating and develops surprisingly quickly (Knight, 1996). The neuropathological findings in irreversible coma give similar findings of brain swelling and softening.
Walker et al (1975), in their study on cerebral survival, reported that brain weight fluctuated, increasing during the first 24 hours after resuscitative measures were started, falling on the second day and then rising again. Patients in whom resuscitation was stopped on the basis of presumed brain death had on the average heavier brains (70 g, P<0.01).
Respirator brain syndrome is described by Walker et al (1975) as a dynamic process that may progress until pulmonary or cardiac disturbances terminate the patient's life or until resuscitation is stopped. The changes seen in respirator brain result from impaired cerebral blood flow causing brain swelling, complicated by concurrent post-mortem changes (Moseley et al, 1976). This process requires approximately 24 hours for maturation (Walker et al, 1975). Factors contributing to respirator brain are acute ischaemia, acidosis, hypoxia, low systolic blood pressure, subnormal temperature, history of respiratory dependency and extensive tissue necrosis (Moseley et al, 1976), and probably present before death in some cases. Although a mechanism similar to that in respirator brain syndrome may provide partial explanation for our findings, it cannot fully explain the relative increase in brain weight in those who died of fatal self-harm, regardless of the method of death, compared to those who died naturally.
The element of bias in the study, although systematic, probably occurred randomly in both groups, so it is unlikely to be solely responsible for the study findings. Moreover, the sample included only persons over the age of 60, so the results cannot be generalised to younger age groups. However, it may prove difficult to obtain enough young subjects who have died naturally to match for age with those who die of FSH. Prospective studies with carefully selected and matched cases and controls may overcome the limitations encountered in this retrospective exploratory study. Data could be obtained from routine neuropathological examination, macroscopically and microscopically assessing the extent of cerebral oedema, brain chemistry and the state of its receptors at death; such investigations should be carried out as a matter of course for all victims of fatal self-harm. As we are dealing with small number of cases (9.7 per 100000) the cost would not be expected to be prohibitive, and the process is certainly feasible.
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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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Courchesne, E, Müller, R. A. &
Saitoh, O. (1999) Brain weight in autism: normal in the
majority of cases, megalencephalic in rare cases.
Neurology, 52,
1057-1059.
Hakim, A. M. & Mathieson, G. (1979) Dementia in Parkinson disease: a neuropathological study. Neurology, 29, 1209-1214.[Abstract]
Harper, C. G. & Blumberg, P. C. (1982) Brain weights in alcoholics. Journal of Neurology, Neurosurgery and Psychiatry, 45, 838-840.[Abstract]
Johnstone, E. C., Bruton, C. J., Crow, T., et al (1994) Clinical correlates of post-mortem brain changes in schizophrenia: decreased brain weight and length correlate with indices of early impairment. Journal of Neurology, Neurosurgery and Psychiatry, 57, 474-479.[Abstract]
Knight, B. (1996) Forensic Pathology (2nd edn). Oxford: Oxford University Press.
Ludwig, J. (1979) Current Methods of Autopsy Practice, pp. 664-665. Philadelphia: Saunders.
Moseley, J. I., Molinari, G. F. & Walker, A. E. (1976) Respirator brain. Report of a survey and review of current concept. Archives of Pathology and Laboratory Medicine, 100, 61-64.[Medline]
Mueller, E. A., Moore, M. M., Kerr, D. C., et al (1998) Brain volume preserved in healthy elderly through the eleventh decade. Neurology, 51, 1555-1562.[Abstract]
Nochlin, D., van Belle, G., Bird, T. D., et al (1993) Comparison of the severity of neuropathologic changes in familial and sporadic Alzheimer's disease. Alzheimer's Disease and Associated Disorders, 7, 212-222.[Medline]
Pearlson, G. D. & Warren, A. C. (1989) Aging and brain weight in Down's syndrome. Neurology, 39, 1407-1408.
Schröder, R. & Saternus, K. S. (1983) Congestion in the area of the head and changes in the brain caused by suicidal hanging death (in German). Zeitschrift für Rechtsmedizin, 89, 247-265.
Szigethy, E., Conwell, Y., Forbes, N. T., et al (1994) Adrenal weight and morphology in victims of completed suicide. Biological Psychiatry, 36, 374-380.[Medline]
Walker, A. E., Diamond, E. L. & Moseley, J. (1975) The neuropathological findings in irreversible coma. A critique of the "respirator". Journal of Neuropathology and Experimental Neurology, 34, 295-323.[Medline]
World Health Organization (1978) The ICD-9 Classification of Mental and Behavioural Disorders. Geneva: WHO.
Received for publication October 21, 1999. Revision received March 1, 2000. Accepted for publication March 3, 2000.