PSYCHO-ONCOLOGY, VOL. 3: 189-195 (1994)

DO CANCER SUICIDES DIFFER FROM OTHERS? P A W HIETANEN. t , JOUKO LONNQVISTS, MARKUS HENRIKSSON" AND PllA JALLINOJAS

t Department of Radiotherapy and Oncology, University Central Hospital of Helsinki, Haartmaninkatu 4, 00290 Helsinki, Finland, $Department of Mental Health, National Public Health Institute, Helsinki, Finland,

OD Department of Psychiatry, University Central Hospital of Helsinki, Helsinki, Finland

SUMMARY Based on a nationwide psychological autopsy study comprising all suicides committed in Finland during one year (n = 1397), victims who had suffered from cancer (n = 60) were compared with other suicides. Cancer suicides were significantly older and more often male, which required adjusting the control group (n = 60) for age and sex. The cancer suicides had more pain and were more often physically disabled. The social network of cancer patients was stronger: 93% of them and 65% of the control cases had a significant other. Family histories of mental disorder were more common in the control group. Cancer was the main underlying factor in the suicide process in 62% of the cancer patients and a contributing factor in 23%. Background factors of the suicide process of the cancer patients with terminal illness (n = 18) were different from those with cancer in remission and from victims among the general population. The frequency of physical symptoms and of depression before suicide in cancer patients emphasizes the need for more competent palliative care and psychological support for cancer patients.

Severe physical diseases like cancer are regarded as important contributing factors in suicide, espe- cially among the elderly (Whitlock, 1986). The suicide rate tends to be somewhat higher among cancer patients compared to the population in general (Sainsbury, 1955; Whitlock, 1978; Lou- hivuori and Hakama, 1979; Marshall et d., 1983; Allebeck and Bolund, 1991; Storm et a/ . , 1992). Suicide can appear t o be a rational alternative to enduring the mental strain and severe physical symptoms of cancer (Siege1 and Tuckel, 1984). Nevertheless, only a small proportion of cancer patients actually commit suicide, even at the ter- minal stage (Bolund, 1985a; Breitbart, 1987), and the wish of terminally ill patients to die has been found associated with emotional disorders (Brown et al., 1986).

Over the past few decades the 'Rational Suicide' movements have emphasized the autonomy of the human being, and the public acceptance of suicides by the terminally ill has been growing (National Opinion Research Center, 1977, 1978, 1982, 1983). The issue of the right of the seriously ill to commit suicide, with or without assistance, has been discussed in the media (Newsweek, August, 1991; Time, May, 1993) and in medical journals (Brody, 1992; Quill et al.,

* Author to whom correspondence should be addressed.

1992). The Hospice movement has highlighted the need for psychological support and more compe- tent palliative care for those with advanced cancer (Greer et al., 1986).

In our previous report (Hietanen and Lonn- qvist, 1991), based on a nationwide study of all suicides in Finland during one year, we were able to show that cancer suicides form a heterogeneous group and that the underlying factors of terminal cancer patients are different from those of patients in remission.

The aim of the present study was to compare factors connected with the suicide in victims who had suffered cancer and those who had not. The hypothesis was that the cancer patients would have specific cancer-related causes for suicide. It was also expected that the background factors of the patients in remission would be similar to those of the general population.

METHOD

Subjects This study was carried out in Finland (popula-

tion 5 million), a country with a high suicide mor- tality (1987: 27.6/100000), and is part of the National Suicide Prevention Project (Lonnqvist,

CCC 1057-9249/94/030189-07 0 1994 by John Wiley & Sons, Ltd.

Received I9 July 1993 Accepted I 6 March 1994

190 P. HIETANEN ET AL.

1988, Lonnqvist et al., 1988). During the research phase of the project, all suicides committed in Finland between 1 April 1987 and 31 March 1988 (n = 1397) were carefully recorded and analysed using the psychological autopsy method (Litman el al., 1963; Shneidman 1981). In every case of violent, sudden or unexpected death, the possi- bility of suicide was assessed by detailed police and medico-legal investigations involving autopsy and forensic examinations. Of the 1397 suicides, 60 (4970) had suffered from cancer (hence called cancer suicides) (Hietanen and Lonnqvist, 1991). The annual figure for cancer suicides was verified using the National Cancer Register, which has ensured reliable statistics in Finland since 1954 (Finnish Cancer Registry and Finnish Foundation for Cancer Research, 1989).

All those who had had cancer at some stage of their life were included in the cancer group, as determined by information obtained from rela- tives or health-care personnel and later confirmed by medical case records. When the cancer suicides were compared with all suicides, the differences in the malelfemale (M/F) ratio and age were signifi- cant. In the former group the M/F ratio was 4.5, whereas it was 3.4 for all suicides. In our material, the M/F ratio for cancer suicides aged over 45 years was 5.8, while for all suicides in Finland for this age group it was only 2.4. The M/F ratio for cancer patients in Finland in 1987 was 0.56. This means that among the cancer suicides there were about eight-times more male victims than

Table 1 . Type of cancer (To) among all cancer suicides (n = 60) and victims with cancer in remission (n = 25)

Cancers in All cancers remission

(n = 25) (n = 64).

N vo N vo

Gastrointestinal tract Head and neck Lung Prostate Lymphoma Breast Melanoma Pancreas Corpus uteri Other

14 22 10 16 9 14 8 13 6 9 3 5 3 5 3 5 2 3 6 9

6 5 1 3 4 1 1

2 2

-

24 20 4

12 16 4 4

8 8

-

Four patients had two cancers.

expected. Of the cancer suicides, 10% were under 45 years old compared to 55Yo of all suicides. The mean age of the cancer suicides was 63 years (range 29-89 years) compared to 45 years (range 9-89) of the non-cancer suicides. Because of the differences in the age and sex distribution between cancer suicides and other suicides, a sex- and age- (22.5 years) matched control group of non- cancer suicides was randomly selected from the nationwide suicide population.

Of the 60 cancer patients, 25 were in remission, 18 at the terminal stage and 17 at other active phases of the disease. The classification was remission if the patient was disease-free, i.e. without signs and symptoms of disease after primary treatment. The classification was terminal if the patient received palliative care without cancer-specific treatment, and death was expected in the near future.

The specific cancer diagnoses for all cancer suicides and cases in remission are shown in Table 1.

The marital variables of the cancer suicides did not differ from those of the control group. The distribution of the sociodemographic variables among all suicide cases are also shown in Table 2. for comparison.

Measures Information about the suicide victims was

obtained via comprehensive interviews of the

Table 2. Sociodemographic variables (To) of cancer patients (n = 60), control cases (n = 60) and all suicides (n = 1397)

Cancer Control All patients cases suicides

(%) (To) (YO)

Sex Male 83 83 77 Female 17 17 23

Married 62 52 39 Single 13 20 40 Divorced 10 10 14 Widowed 15 18 7 Age c45 years 10 10 55 45-64 years 30 30 30 >64 years 60 60 15

Marital status

CANCER SUICIDES 191

relatives and attending health-care personnel. Medical, social agency, police and other available records, as well as all suicide notes were also carefully scrutinized.

The interview forms (available from Dr Lonnqvist on request) were planned for the pro- ject, and the interviewers were mental health pro- fessionals trained in their use.

The next of kin or other intimate associates were interviewed at home about 4 months after the suicide. For each case, the person considered able to provide the most complete information on the suicide process and its background was selected as the interviewee. The structured inter- view forms contained 234 items concerning the victim’s everyday life and behaviour, family fac- tors, use of alcohol and other drugs, previous suicidality, help-seeking and life events. Inter- views of the relatives were conducted about 4 months after the suicide and the mean duration of interviews was 2 h 45 min. It was possible to inter- view 80% of the relatives of the cancer suicides and 87% of the relatives of the control cases.

Health-care professionals who had attended the victim during the previous 12 months were inter- viewed with a structured form containing 113 items about the victim’s state of health, treatment in the health-care system, psychosocial symptoms, stressors and level of functioning. This interview included a cross-sectional symptom questionnaire and questions about longitudinal aspects of mood changes and substance abuse. In addition, a semi- structured interview containing eight items about the victim’s motive for the last contact and possible communication to intention to commit suicide was conducted with the last health or social care professional the victim had consulted before death. Additional unstructured interviews by telephone were done when needed. Infor- mation from medical, social agency, police and other available records, as well as all suicide notes, were included. A multidisciplinary team discussed all the cases, and a comprehensive case report was written on the basis of all information available. The more detailed description of the data collection has been presented elsewhere (Marttunen et ul., 1991; Henriksson et al., 1993).

The role of cancer or other serious physical illness in the suicide process was assessed from the interviews with relatives and health-care per- sonnel. When the suicide was clearly related to a change of life caused by serious somatic illness, awareness of brief life expectancy or severe

somatic symptoms, cancer (or another illness) was considered the main underlying factor. Take the case of a previously healthy 30-year old man as an example. Sport was his main hobby and source of social contacts. When he was diagnosed with melanoma, he started off hopefully. As the cancer progressed and he lost his job, hobby and friends, however, he became depressed and eventually committed suicide.

Illness was considered a contributory factor (but not main) in cases where patients had not adapted to a disease which had compounded their existing psychosocial problems. In these suicides the immediate trigger had been some other problem. An example of this is the case of a middle-aged nurse who, prior to cancer, had had trouble with alcohol and social problems. In the interviews she was described as an elegant woman, for whom appearance was a central feature of her self-esteem. Because of breast cancer a mastec- tomy was performed, after which her problems with alcohol and marital difficulties worsened. Three years after the diagnosis she attempted suicide, was admitted to a psychiatric ward and committed suicide after discharge.

Diseases classified as serious, apart from cancer, were chronic conditions markedly affecting functional capacity, such as severe arthrosis, hemiplegia and angina pectoris.

Pain was graded as severe if it had been treated with opiates or described as a severe or significant clinical problem by the relatives or health-care personnel. Pain present to some extent included, inter aliu, pain resulting from arthrosis and treated with non-steroidal anti-inflammatory drugs, as well as occasional pain. Other severe symptoms included continuous nausea, irritable cough and severe dyspnoea.

The victim was classified as disabled if func- tional capacity was clearly restricted due to the disease, e.g. impaired walking ability due to bone metastases or hemiplegia.

When assessing the available social support, the current state of important personal relationships in addition to close relatives was taken into account. Relationships were classified as in con- flict if they were described as quarrelsome, if they involved mental or physical violence or if they were very ambivalent.

Histories of mental disorders, psychiatric treat- ment, depression and withdrawal from social con- tacts three months before suicide were assessed by weighing and integrating all the information gath-

ered in each case. All health-care contacts due to psychological problems were classified as psychia- tric treatment, including those due to sleeping problems.

In statistical analysis cancer suicides are compared to non-cancer suicides using Fisher’s extlract test. A probability level of <0.05 was considered significant. Percentages were counted of cases on which we had information.

RESULTS

Cancer was the main underlying factor in the suicide process in 62% of cancer suicides and a contributing factor in 23%. In 15% we were unable to find any meaningful relationship between the suicide process and cancer. Of the patients at the terminal stage, cancer was always the main underlying factor in the suicide process. In the control group some other serious somatic illness was assessed as the main factor in 20% and a contributing factor in 23% of the suicides.

The prevalence of illness other than cancer was considerable among the whole material, and sub- jects of both groups had had many symptoms related to their somatic illness (Table 3 ) . The prevalence of pain was higher in cancer suicides than in control suicides in general (Table 3), and the difference was more striking when terminal cancer patients were compared to their matched control cases (1OOqlo versus 40’70, p c 0.001). Physical disability was also more common among cancer patients than controls, the difference being greatest between terminal cancer patients and their matched controls (88% and 28%, p < 0.001).

The methods of suicide did not differ between

Table 3. Somatic variables of cancer patients (n = 60) and control cases (n = 60)

Cancer Control patients cases

Significance “70 N % N P

f 92 P. HIETANEN ET AL.

* Severe or present to some extent.

Other serious illnesses 60 (38/58) 66 (33/50) N.S. Physical disability 64 (38/59) 41 (24/58) <0.05 Pain* 75 (43/57) 50 (25/50) <0.01 Other severe symptoms 82 (46/56) 71 (37/52) N.S.

the two groups (Table 4). None of the suicides by the cancer cases was committed with cancer drugs or analgesics. Another similarity in both groups was the location of the suicide: 68% of the cancer cases and 63% of the controls committed suicide at home. Six (10%) of the cancer patients and three ( 5 % ) of the control cases committed suicide in hospital.

Ninety-three percent of the cancer patients compared to 65% of the control cases had a family member, close relative or someone else as a significant other ( p < 0.001). Conflicts in these relationships tended to be more common in the control group than in the cancer patient group, at 54% and 36070, respectively, although the differ- ence was not statistically significant.

Forty-four percent of the relatives of the cancer suicides and 26% of the non-cancer suicides said that they accepted the decision of the deceased to commit suicide (N.S.). Two-thirds (63% and 67%, respectively) of the relatives said that they experienced guilt, anger or rejection when ques- tioned about the feelings evoked by the suicide.

Family histories of mental disorder were more common among control cases than cancer patients (59% versus 3470, p < 0.05). There was no statis- tically significant difference in the family histories of suicide between the cancer and control groups (32% and 28%, respectively).

Fifty percent of the cancer patients and 56% of the control cases had a history of psychiatric treatment. The life-time prevalence of alcohol related problems was 27% in cancer patients and 31% among controls. In the cancer patient group, 29% had attempted suicide previously: seven ( 1 3 070) before the diagnosis and nine (16%) subse-

Table4. Methods of suicide (Yo) among the cancer patients (n = 60) and the control group (n = 60)

Cancer Control patients group

N Va N Vo

Hanging 28 47 26 43 Firearms 14 23 1 1 18 Drugs 5 8 11 19 Inhaling carbon monoxide 5 8 - - Drowning 2 3 3 5 Jumping from high place 1 2 3 5

6 10 Other 5 8

193 CANCER SUIClDES

Table 5. The statistically significant differences between the cancer patient group (n -60) and the control group (n = 60)

Cancer Control patients cases

% N % N Significance

P

Pain 75 (43/57) 50 (25/50) <0.01 Physical disability 64 (38/59) 41 (24/58) <0.05 Significant other 93 (56/60) 65 (39/60) <0.001 Family history of mental disorder 34 (16/47) 59 (23/39) ~ 0 . 0 5

quently. The proportion of suicide victims with a history of attempted suicide was somewhat higher, at 4470, in the control group, although the difference was not statistically significant.

Suicidal behaviour prior to death was not dif- ferent among cancer suicides and non-cancer suicides. In both groups, depressive mood and withdrawal from social contacts were common during the final three months. According to the relatives or health-care personnel, 90% of the cancer patients were depressed and 62% withdrew from social contact before death. The corre- sponding figures in the control group were 90% and 65%. About one-half the patients in both groups (54% versus 62%) had expressed suicidal thoughts, while 20% of cancer suicides and 28% of control cases had left a suicide note. Long letters by cancer patients were rare; usually the notes comprised only a couple of sentences like, ‘I am sorry, I could not take it any more, please forgive me’, or ‘I left the dog in the garage’, or ‘I owe 10 marks to the ambulance driver’. The cancer patients did not analyse their lives deeply, at least in writing, more frequently than the control cases.

All statistically significant differences between the cancer and non-cancer suicides are shown in Table 5 .

When the cancer patients in remission (n = 25) were compared with their matched control cases, nearly all the differences disappeared. The only statistically significant difference was that 92% of the cancer patients in remission had significant others compared to only 56% of the control cases ( p < 0.001).

DISCUSSION

The present study was based on the psychological autopsy data from a one-year Finnish suicide population. The study subjects comprised all suicide victims who had suffered from cancer, among whom there were about eight times more males than expected. The control group represents sex- and age-adjusted other suicides from the nationwide population.

Determination of causes of death in Finland is considered reliable (Lonnqvist et al., 1988; Palonen et al., 1990). During the project, police investigations to determine the cause of a violent death and medico-legal examinations to determine the cause and mode of death were even more detailed than usual. The possibility remains, how- ever, that some suicides among terminal cancer patients were misclassified as natural deaths.

The present study shares the methodological problems of psychological autopsy studies based on indirect information about the suicide victims (Shaffer et al., 1972; Shneidman, 1981; Brent, 1989; Beskow et a!., 1990; Clark and Horton- Deutsch, 1992). The informant’s effort to explain the suicide may lead to overreporting symptoms and psychological problems (Paykel, 1989). On the other hand, possible incompleteness of data and various sources of recall bias may lead to underreporting. Collecting information from different sources, including all available records, and comparing study groups by the same method, improves the accuracy of results.

Hanging was the most usual suicide method both among cancer suicides and other suicides. It is worth noting that not a single cancer patient committed suicide with analgesics or cancer medication, in contrast to a Swedish study of cancer suicides (Bolund, 1985a) where drugs, including pain killers, were the most common method. The Swedish study involved more females than the present study, among whom poisoning with drugs was significantly more common than among males, as in the general population (Rich et al., 1988). However, the difference between the present study and the Swedish material may also reflect the lower avail- ability of toxic drugs to Finnish cancer patients.

In our study, cancer was clearly the main underlying factor in the suicide process in 62% of the cancer cases. Although the control cases mainly represent elderly suicide, the importance

194 P. HIETANEN ET AL.

of somatic disease was much less in their suicide process.

Pain is considered one of the major risk factors for suicide among cancer patients (Breitbart, 1987; Owen et a/., 1992). In previous studies, the majority of cancer suicides suffered severe pain that was often not adequately controlled (Farberow et a[., 1963, Bolund, 1985b). The present study, as expected, showed that the cancer suicides had significantly more pain and were more often physically disabled compared with the non-cancer suicides. However, one-half of the control cases also had pain and two-thirds had other severe somatic symptoms which impaired their quality of life. Most suicide victims, with or without cancer, suffered somatic symptoms.

According to a questionnaire study (Vainio, 1988) the treatment of cancer pain in Finland was not adequate at the time of the present study. Physicians often prescribed opioids at levels well below the minimum effective daily doses and as many as one-half of them failed to use the approved therapeutic modalities correctly, irrespective of the frequency of seeing cancer patients. Retrospective assessment of the adequacy of pain treatment of the subjects of the present study is difficult, but our impression is that in at least one fifth (9 out of 43) of the cancer suicides suffering pain the analgesic medication was insufficient.

Suicidal behaviour and the presence of depressive mood and withdrawal from social con- tacts prior to suicide were not different among cancer suicides compared with control cases, but the supportive social network of the control sub- jects was comparatively weaker. A family history of mental disorders or a lack of significant others was more common among the control cases. Although almost all suicide victims with cancer had a significant other or others for potential social support, this apparently did not help them avoid suicide when burdened with cancer-related and other problems.

More relatives of cancer suicides than of control cases tended to accept the decision of the victim, although the difference did not reach stat- istical significance. However, whether suicide is regarded as rational and justified or irrational and unjustified, for those left behind the bereavement of suicidal death seems to be difficult. The majority of relatives in both groups experienced feelings such as guilt, anger or rejection after the suicide.

As expected, the background factors of the suicide victims with cancer in remission, were, compared with other cancer suicides, more similar to those of their control cases. Cancer was the main underlying factor in 24% of the cases in remission, many of whom had lived several years since diagnosis and experienced psychosocial difficulties throughout their life. However, cancer was a contributing factor in the suicides of 52% of these cases, which indicates that the psycho- logical impact of cancer remains high even when the disease is not in the active phase. Because the background factors of cancer suicides in various phases of illness differ, suicides of cancer patients should not be studied as a homogeneous group in future studies.

Cancer suicides can be considered as rational or ‘natural’ deaths if the subject is suffering unbear- able chronic physical symptoms without any realistic prospect of improvement and if the mental processes leading to the decision to commit suicide are unimpaired by mental disorder or severe emotional distress (Siegel, 1986; Diekstra, 1992; Quill, 1992). The majority of cancer patients of the present study were phy- sically disabled and in many cases their pain symptoms had not been relieved effectively. As with other suicides, the cancer suicides suffered both subjective and objective psychological problems, and depression may have caused cognitive distortions about the disease and its prognosis.

The findings of the present study do not support the rationality of cancer suicides but rather emphasize the importance of educating physicians in the effective treatment of pain and depression in cancer patients. Many suicides among patients suffering malignant disease seem understandable, but these findings clearly suggest that improved palliative care and psychological support could prevent many of them.

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