Suicide in older people
Elderly people have a higher risk of completed
suicide than any other age group
worldwide.1
Despite this, suicide in elderly
people receives relatively little attention,
with public health measures, medical
research, and media attention focusing on
younger age groups.2
We outline the epidemiology and causal
factors associated with suicidal behaviour
in elderly people and summarise the
current measures for prevention and management
of this neglected phenomenon.
From time immemorial, suicidal feelings and
hopelessness have been considered
part of ageing and understandable in the context
of being elderly and having physical
disabilities. The Ancient Greeks
tolerated these attitudes in the extreme and
gave elderly people the option of
assisted suicide if they could plead
convincingly that they had no useful
role in society. Such practices were
based on the assumption that once an individual
had reached a certain age then they
no longer had any meaningful purpose
in life and would be better off dead. Although
not as extreme, ageist beliefs in
modern, especially industrialised, societies
are based on similar assumptions. Sigmund
Freud echoed such views, while
suffering from incurable cancer of the palate:
It may be that the gods are merciful when they
make our lives more unpleasant as we
grow old. In the end, death seems less
intolerable than the many burdens we have
to bear.
Recent developments
-Elderly people have a higher risk of completed
suicide than any other age group worldwide
-The main psychological factors
associated with suicide in elderly people
include psychiatric illnesses, most
notably depression, and certain personality
traits
-Physical factors include neurological illnesses
and malignancies
-The effects of physical health factors on
suicide in elderly people are
generally mediated by mental health factors
-Social factors include social
isolation and being divorced, widowed,
or single
-Those who have attempted suicide are at high
risk of a subsequent completed
suicide
-The burden of suicide is often calculated in
economic terms and, specifically,
loss of productivity.
Despite lower rates
of completed suicide in younger age
groups, the absolute number of
younger people dying as a result of suicide is
higher than that for older people
because of the current demographic structure
of many societies.1
Younger people are also more likely to be
in employment. Therefore the economic cost
of suicide in younger people is more
readily apparent than that in older people.
One model of the suicidal process is that
suicidality exists along a continuum
(figure).
Following this model, the epidemiology
of suicidal behaviours in elderly people
can be described broadly under the
headings of suicidal ideation, attempted
suicide, and completed suicide.
The
burden of suicide should not, however, be
measured solely in such reductionist
terms, and the extent of the real burden
on families and communities from suicide
in elderly people cannot be
overemphasised. Furthermore, the ageing of
populations worldwide means that the
absolute number of suicides in elderly people
is likely to increase.
Epidemiology of suicidal behaviours
The prevalence of hopelessness or suicidal
ideation in elderly people varies
from 0.7-1.2% up to 17% in different studies,
depending on the strictness of criteria
used.3
w2 A universal finding is
the strong association with psychiatric illness,
particularly depression. The prevalence of
suicidal feelings in mentally healthy
elderly people has been reported to be as
low as 4%.w3 These findings are
therefore contrary to the ageist
assumption that hopelessness and suicidality are
natural and understandable
consequences of the ageing process.
Rates of completed suicide in elderly people
vary between cultures, but pooled
international data published by the World Health
Organization show a steady rise in
prevalence of completed suicide with
age. For men, the rate increases from 19.2 per
100 000 in the 15-24 year old age
group to 55.7 per 100 000 in the over
75s. For women, the respective rates are 5.6 per
100 000 and 18.8 per 100 000.1
The male to female ratio for completed suicide
in the elderly is 3 or 4:1, similar to
that of other age groups.
Although the prevalence for completed suicide in
elderly people does not at first
suggest a major public health problem, completed
suicides are likely to represent only the
tip of the iceberg for psychological,
physical, and social health problems in older
people.
According to a comprehensive review of
psychological autopsy studies, 71-95%
of elderly people who completed suicide had
a psychiatric illness, most commonly
depression.4
Major depressive disorder has been
found to be more common in completed suicides
among older people than among younger
counterparts and may affect as many
as 83% of elderly people who die as a result of
suicide.5
The prevalence of completed suicide is,
however, relatively low among elderly
people with primary psychotic illnesses,
personality disorders, anxiety
disorders, and alcohol and other substance
use disorders.4
Data for suicidal behaviours, especially
attempted suicide, between elderly
and younger people suggests that different
phenomena are involved.
The ratio of parasuicides to completed suicides
in elderly people is much lower than
that among younger people and among the general
population (200:1 in adolescents, 8:1-33:1
for the general population, and 4:1
in elderly people).4
Suicidal behaviour among elderly
people is therefore more likely to carry a
higher degree of intent. This is
further supported by the reported increased
use of lethal means by older people, such
as firearms and hanging.w4-w7
Factors associated with suicide in elderly
people: re-examining the files of usual suspects
A wide variety of factors have been implicated
in suicidal behaviour in elderly
people. These can be described broadly as
psychological, physical, and social
factors. Such factors are either modifiable,
such as physical and psychiatric illness,
or non-modifiable, such as sex and
social class. A description of modifiable and
non-modifiable factors may provide
insights into factors associated with
suicidal behaviour in elderly people.
The case-control study, using psychological
autopsies (information gathered after
death from relatives, healthcare professionals,
and medical records), is the most commonly
used method for examining risk
factors and associations for suicide in older
people. Recent research has also
focused on differences in risk factors for
suicide between "young old" (under 75
years) and "old old" populations.6
w8 The importance of such research is
reflected in the epidemiology of
suicide in elderly people, in view of the
increased risk for those aged over 75
years.1
Psychological factors
According to psychological autopsy studies of
suicides in elderly people, 71-95% of
the people had a major psychiatric disorder
at the time of death.4
Depressive illnesses are by far the most
common and important diagnoses. In the
only prospective, non-clinical cohort
study of older people to date in which completed
suicide was the outcome, self rated
severity of depressive symptoms was
the strongest predictor of suicide.7
Those people in the poorest summary
score category were 23 times more likely to
die as a result of suicide than those with
the least depressive symptoms. Other
important psychological factors included
drinking more than three units of
alcohol a day and sleeping nine or
more hours at night.
The generalisability of
these results is limited, however,
because the people were living in a retirement
community. A recently published
retrospective case-control study
found that alcohol use disorders predicted
suicide in older people.8
A history of alcohol dependence or misuse was
found in 35% of elderly men and 18%
of elderly women who had died as a
result of suicide, with corresponding rates in
controls of only 2% and 1%.
A review summarised the findings of four
psychological autopsy studies that
examined the effect of psychiatric illness on
completed suicide.4
Any axis I psychiatric disorder was associated
with a substantially increased risk
of completed suicide, with odds
ratios ranging from 27.4 to 113.1.
One of the
studies found an odds ratio of 162.4
for recurrent major depressive disorder,
with single episode major depression,
dysthymia, and minor depression being
important but less powerful predictors of
completed suicide.9
Older people with psychotic depression may have
a still further increased risk of
completed suicide, although a recent study
found no difference in the numbers of
suicide attempts between psychotic
and non-psychotic depressed elderly inpatients.
Other psychiatric illnesses,
such as anxiety disorders, psychotic disorders,
and substance use disorders, have also been
implicated as risk factors for suicide in
elderly people, but seem to be significantly
less important than depressive illnesses.4
Although three of the four studies that examined
dementia diagnoses found no significant
difference between people who died as a result
of suicide and controls, more detailed
examination of the nature and anatomical
location of cerebrovascular disease is likely to
provide clinically useful information in the
future.4
Traditionally, an increased risk of suicide in
patients after stroke was thought to be
secondary to depression and functional
impairment.w10 However, strategic infarcts
specifically affecting frontal and subcortical
circuitry have been associated with both
depression and impulsivity, and the importance
of cerebrovascular disease in suicidal thoughts
and behaviour in older people has been
argued.w11 In addition, a case-control study
found that Alzheimer's disease was
over-represented at autopsy in elderly people
who had died as a result of suicide.w12
In keeping with findings in younger populations,
significantly lower concentrations of
5-hydroxyindoleacetic acid and homovanillic acid
have been found in the cerebrospinal fluid of
elderly people who died as a result of suicide
compared with non-suicidal and normal
controls.w13
The roles of personality type and traits have
been studied in elderly people who died as a
result of suicide. Clinical experience suggests
that the effects of ageing on the brain,
physical health problems, and life events such
as bereavement may coarsen or accentuate
pre-existing maladaptive personality traits in
certain elderly people and make them more likely
to engage in suicidal thinking or behavior.
Elderly people who die as a result of suicide
have been shown to have higher levels of
neuroticism and lower scores for openness to
experience, having a restricted range of
interests and a comfort with the familiar.10
Interestingly, the only controlled study
assessing personality disorder diagnosis, found
that it was not over-represented in elderly
people who died as a result of suicide.w14
A follow up study of 100 elderly people who had
attempted suicide two to five years after the
index attempt found that 42 had died, 12 being
suspected suicides and five dying as a delayed
result of the index attempt.11
Twelve women had attempted a further non-lethal
attempt and five men had completed suicide after
a further attempt. Recent case-control studies
identified a history of a suicide attempt as a
risk factor for suicide in older people.12
w15 These studies highlight the importance of
secondary prevention strategies targeted at
those who have attempted suicide.
Physical factors
Although problems with physical health and level
of functioning are important in the cause of
suicidal behaviors, controlled studies suggest
that their effects are generally mediated by
mental health factors, most notably depression.
A recent psychological autopsy study of
completed suicide in nursing home residents
highlighted the complex interplay between
physical and psychological factors.13
Having more than three physical illnesses and a
history of peptic ulcer disease in a population
sample of community dwelling residents aged over
85 years were predictive of increased suicidal
feelings.w3 Physical health and disability seem
to be associated independently of depression
with the "wish to die."w16 This death wish was
also found to be associated with the highest
comorbidity in a large sample of older patients
attending their general practitioner for
depression, anxiety, and at risk alcohol use.w17
Based on a review of 235 prospective studies,
physical disorders were associated with an
increased risk of suicide, including HIV/AIDS,
Huntington's disease, multiple sclerosis, peptic
ulcer, renal disease, spinal cord injury, and
systemic lupus erythematosus.w18 A retrospective
case-control study, however, found that neither
current serious physical illness nor a visit by
a general practitioner in the previous month was
significantly associated with completed
suicide.w15 Two other retrospective case-control
studies found the burden of physical illness and
current serious physical illness to be
significantly associated with completed suicide
in elderly people.14
15
Depression was not accounted for in the first of
these studies, however, and when included in the
analysis in the second study, the effects of
physical illness became non-significant.4
A retrospective case-control study did find that
serious physical illnesses (visual impairment,
neurological disorders, and malignant disease)
were independent risk factors for suicide.9
The authors concluded that serious physical
illness may be a stronger risk factor for
suicide in men than in women, implying that
elderly males may be more vulnerable to the
effects of physical health problems. These
findings have important implications for the
detection and management of suicide in elderly
people, highlighting the importance of
psychiatric evaluation in people with physical
disorders.
There are also important ethical implications;
the fact that there is a high prevalence of
potentially treatable psychiatric illness in
those elderly people who have both physical
illness and suicidal ideation should be central
in any discussion on physician assisted suicide.
Social factors
As with other age groups, elderly people seem to
have an excess of stressful life events in the
weeks before suicide. The nature of these may
differ in older people, with more emphasis on
physical illness and losses, such as
bereavement, and less emphasis on interpersonal
discord, financial and job problems, and legal
difficulties; these last four factors are more
typically associated with suicide in younger
populations.16
Some recent studies have, however, found an
association between interpersonal discord and
suicide, even in later life.17
w19
Decreased social support and social isolation
are generally associated with increased suicidal
feelings in elderly people.w17 w20 An
influential study suggested that elderly people
who had died as a result of suicide were more
likely to have lived alone.18
More recent studies do not agree with these
findings, but they did report that loneliness
and low social interaction were predictive of
suicide.12
17 w15
Religiosity and life satisfaction were found to
be independent protective factors against
suicidal ideation in elderly
African-Americans.w21 Similar findings have been
reported in terminally ill elderly people, where
higher spiritual wellbeing and life satisfaction
independently predicted lower suicidal feelings.19
In general, widowed, single, and divorced
elderly people have a higher risk of suicide,
with marriage seeming to be protective.
Bereavement is also associated with attempted
and completed suicide in elderly people—men seem
especially vulnerable after the loss of a
spouse, with a relative risk three times that of
married men. In contrast, widowed and married
elderly women seem to have a similar risk.16
A recent study concluded that the protective
effect of marriage was not apparent in those
aged over 80 years, showing how risk factors for
suicide may differ between young old and old
old.w8
Although several social factors associated with
suicide in elderly people are non-modifiable,
they may give clues as to the underlying
biological processes involved in suicidal
ideation and behaviour. For example, the
increased vulnerability of elderly men to
bereavement and physical illness may be mediated
by relatively higher levels of cerebrovascular
disease and alcohol use disorders compared with
elderly women.
Despite the higher risk of completed suicide in
elderly people compared with younger age groups,
the low absolute prevalence rate does not
justify screening of the entire elderly
population. Screening for suicidal ideation
should be opportunistic, with high risk
subgroups defined and targeted, based on
knowledge of psychological, physical, and social
factors. High risk subgroups include those with
depressive illnesses, previous suicide attempts,
or physical illnesses, and those who are
socially isolated. Elderly people with multiple
such factors warrant special attention.
Older people are less likely to volunteer that
they are experiencing suicidal feelings.w22
Moreover, these feelings may be present in
patients with few depressive symptoms, and
feelings might not be manifest unless asked
about directly. Healthcare professionals should
be trained and encouraged to ask such questions
directly. The presence of suicidal feelings in
depressed patients also predicts a lower
response to treatment and an increased need for
augmentation strategies, thereby identifying a
group of patients who may need secondary
referral.
The estimated population attributable risk for
mood disorder in elderly suicide is 74%.w15 This
means that if mood disorders were eliminated
from the population, 74% of suicides would be
prevented in elderly people. "Elimination" of
mood disorders is achieved not only by treatment
of existing cases but also by the prevention of
new cases and secondary prevention of
subclinical cases.
The level of detection and
treatment of depression of all ages in the
general population is low, and only 52% of cases
that reach medical attention respond to
treatment.20
21
Detection rates and treatment response are
likely to be still lower in elderly people.
Thus, although treatment of depression is vital
in combating suicide in elderly people,
preventive measures at an individual and
population level are also essential. Improved
physical and emotional health, exercise, and
modification of lifestyle should promote
successful ageing and lead to a decrease in the
incidence of suicidal feelings.
Key ongoing research
The Dublin healthy ageing study (Mercer's
Institute for Research on Ageing, St James's
Hospital)—a community based study examining
physical, psychological, and social health
factors, including an assessment of suicidal
ideation, in a sample of community dwelling
elderly people in Dublin
Institute of Clinical Neuroscience, Section of
Psychiatry, Sahlgrenska Hospital, Gothenburg,
Sweden—research on suicide in elderly people
carried out at this institute has contributed
greatly to knowledge of the topic
Interventions at population level that improve
social contact, support, and integration in the
community are also likely to be effective,
especially considering that the population
attributable risk factor for low social contact
is 27%.w15 For example, telephone help lines
have been associated with a significant
reduction in completed suicide in elderly
people.w23
Limiting access to the means of suicide (for
example, over the counter medicines) or
decreasing the chance of completed suicide (for
example, reducing the lethality of car exhaust
fumes with catalytic converters) have been shown
to have benefits for the general population and
are also likely to affect suicide rates in
elderly people, particularly considering the
increased use of lethal means by older people.22w4-w7
An appropriate strategy for the prevention of
suicide might be the introduction of
opportunistic screening for hopelessness and
suicidal feelings in elderly people who visit
their general practitioner. This is especially
important because of the high level of contact
found between elderly people and their general
practitioner in the week before suicide (20-50%
contact) and in the month before suicide (40-70%
contact).16
The Gotland study highlighted the importance of
training for general practitioners to lower the
incidence of suicide in all age groups.w24 Such
training is also likely to lead to improved
detection and management of elderly people with
suicidal tendencies.
A study of depression in
primary care highlighted the importance of
increasing doctors' awareness of depression and
suicide in elderly patients.23
Compared with young adults with depression, old
old (over 75 years) patients were only 6% as
likely to be asked about suicide, one fifth as
likely to be asked if they felt depressed, and
one fourth as likely to be referred to a mental
health specialist.
Conclusions
Suicide in elderly people is a complex and
multifactorial phenomenon. Elderly people are
frequently sidelined in discussions on suicide,
perhaps as a result of factors such as a higher
overall number and a higher economic burden
associated with suicide in younger people and
ageist beliefs about the elderly and ageing in
modern, particularly industrialised, societies.
Screening, prevention, and management programmes
should focus more on elderly people, in view of
the inherent increased risk of suicide in this
population. More specifically, there is a need
for vigorous screening and aggressive treatment
of depression and suicidal feelings in elderly
people, especially in subgroups with additional
risk factors such as those with comorbid
physical illness and those who are socially
isolated.
