Section of Psychiatry, Institute of Clinical Neuroscience, Sahlgrenska University Hospital, Göteborg University, SE 413 45 Göteborg, Sweden
Received 7 October 2002; in revised form 1 December 2002; accepted 18 December 2002
![]() |
ABSTRACT |
---|
![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() |
---|
![]() |
INTRODUCTION |
---|
![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() |
---|
|
![]() |
SUBJECTS AND METHODS |
---|
![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() |
---|
The next-of-kin for 98 of the 100 potential study cases were identified and informed about the study. Informants for 85 suicides (46 men and 39 women) agreed to participate. As reported earlier (Waern et al., 2002), suicides with an informant interview did not differ from the total suicides in terms of mean age, proportion of women, proportion of certain suicides, and proportion with a positive screening for antidepressants and/or lithium at necropsy.
The comparison group
Two persons living in the same area of residence and with the same sex and birth year (±2 years) as the person who committed suicide were randomly chosen from the tax roster. Potential control persons received a letter of information about the study and were then contacted by telephone. When an individual declined participation, a new person was invited to take part in the study (a maximum of eight per case). In all, 240 persons were invited to take part in the study and 153 (64%, 84 men, 69 women) accepted. Reasons for declining included poor health (n = 13), social reasons (n = 8) and lack of interest (n = 60).
The interview
The semi-structured interview included questions about the subjects social situation, life events, past and current mental and physical health, history of suicidal behaviour, use of alcohol and illicit drugs, contacts with in- and out-patient services, and use of prescription drugs. The interview included past month psychiatric signs and symptoms derived from the Comprehensive Psychiatric Rating Scale (Åsberg et al., 1978) and questions about dementia symptoms (Skoog et al., 1993
). Past year life events were rated according to a revised version of the Recent Life Change Questionnaire (Paykel et al., 1969
), modified by Heikkinen et al.(1994)
. All life events were self-reported for the controls and informant-reported for the suicides.
The author, a psychiatrist, performed all informant interviews for the suicide cases. Interviews with control persons were carried out by a geriatrician, a psychiatric nurse or a psychiatric occupational therapist, all with long clinical and interview experience. In order to reduce the risk of non-participation due to poor health, proxy interviews with informants were carried out for 11 control persons who could not participate actively due to serious illness.
Record reviews
Case notes from psychiatric in- and out-patient clinics and primary care facilities were reviewed for the suicide cases. Records from other disciplines (e.g. internal medicine, geriatrics, oncology) were obtained when deemed relevant on the basis of the informant interview. Individuals in the control group were asked about contacts with health care services and their case records were requested on the basis of this information. Seven control persons did not agree to the release of their records.
Forensic reports were scrutinized in order to assess alcohol use in connection with the suicide and type of suicide method. Post-mortem analysis of alcohol in blood and urine specimens was carried out at the Institute of Forensic Chemistry in Linköping for 82 of the 85 suicide cases. Suicide method was determined by the forensic examiner. For the purpose of this report, drug overdose, drowning and carbon monoxide poisoning were classified as non-violent methods (Conwell et al., 1998). Hanging, shooting, jumping and collision with a train were classified as violent methods.
Diagnosing mental disorders
The author used data from interviews, case records and forensic reports (suicide cases only) to make retrospective diagnoses according to the diagnostic algorithms of the DSM-IV Axis I (American Psychiatric Association, 1994). Cases with symptom constellations that did not fit the diagnostic algorithms were assigned best estimate diagnoses after discussion with a senior psychiatrist. A more detailed description of diagnostic procedures is given in our recent report (Waern et al., 2002
).
Statistical analysis
In the univariate analyses, odds ratios (ORs) for suicide among persons with a disorder compared to those without the disorder were calculated with logistic regression. Due to a lag between the suicide deaths and the control interviews, the controls were somewhat older than the suicide cases at the time of the interview (mean age ± SD in suicide victims 75.0 ± 7.7 years, in controls 78.8 ± 7.7 years). Therefore, all ORs were adjusted for age. Variables that were included in the multivariate regression models (enter) for men and women included major depression, alcohol dependence/misuse (ADM), family conflict and serious somatic illness. For the purpose of this study, serious somatic illness was defined as a rating of 3 or 4 in any somatic category in accordance with the Cumulative Illness Rating Scale for Geriatrics (CIRS-G) (Miller et al., 1992).
Fishers exact test was employed to examine differences in proportions between suicide subgroups with and without substance misuse disorder. The t-test was used to compare continuous variables. Two-sided P-values were applied (P < 0.05). All exploratory and formal statistical analyses were performed with SPSS version 10.1 for Windows.
Ethics
Informed consent was obtained from the informants and the control persons after they had received oral and written information about the study, including an assurance that they could withdraw from the study at any time. A close relative gave proxy consent for control persons suffering from dementia. The Research Ethics Committee at Göteborg University approved the study.
![]() |
RESULTS |
---|
![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() |
---|
|
|
|
![]() |
DISCUSSION |
---|
![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() |
---|
Secondly, we have no data regarding alcohol use among potential control persons who declined participation. It is likely that persons with alcohol problems would decline participation more often than those without. We note, however, that the 1 month prevalence rate of alcohol use disorder in our control group (0.7%) was similar to that reported for the 65+ population in the Epidemiological Catchment Area Study (Regier et al., 1984). Still, the prevalence of alcohol use disorder may have been underestimated in our study. Seven control persons did not consent to the release of their case records, and one reason for this might be unwillingness to disclose a diagnosis of alcoholism.
Thirdly, the rater was not blind to casecontrol status. This problem was alleviated somewhat by the use of case notes for both suicides and controls. These notes were recorded by clinicians before the suicides occurred. Clinicians had identified alcohol use disorder and recorded this in the case notes of all eight women who received a study diagnosis of alcohol use disorder. This was also the case in 14 of the 18 men with such a study diagnosis.
Fourthly, while control persons were interviewed in person, data for the suicide cases were collected from informants. There is an inherent risk that informants may under-report psychiatric symptoms due to memory bias and guilt feelings. Recent research, however, speaks for the validity of proxy-based data in suicide research (Conner et al., 2001). Agreement was substantial for alcohol dependence in that study, but poorer for misuse. Several of the informants in the current study appeared uncomfortable with questions related to the decedents alcohol intake. This, taken together with the observation that the DSM-IV criteria for alcohol use disorder are not particularly suited to the elderly (Hocking et al., 1995
), suggests that the proportion of suicides with a history of alcohol use disorder in the current study (27%) represents a minimum figure. A final limitation of import is the small size of some of the subgroups, which is reflected in the large CI.
Findings
The main finding was a strong association between alcohol use disorder and suicide in persons 65 years of age and above. The estimated risk of suicide was even higher than that (OR = 8.4) observed in a study of mixed-age suicides in Northern Ireland (Foster et al., 1997). One reason for the higher OR was the very low frequency of alcohol use disorder in the control group, which was expected, considering the advanced age of the participants. Alcohol use disorder was observed in 27% of the suicide victims in our study, a figure similar to those reported from previous uncontrolled studies of elderly suicides in the USA (Clark and Clark, 1993
) and Finland (Henriksson et al., 1995
), but considerably higher than the 3.8% observed in a recent British study (Harwood et al., 2001
). The low rate of alcohol misuse among elderly suicides in this latter study was consistent with previous British findings (Barraclough, 1971
). Thus, the disparate findings presented in Table 1
may reflect real international differences. There is evidence, on a population level, that the association between alcohol and suicide is more pronounced in dry northern European cultures than in settings with higher per capita alcohol consumption (Ramstedt, 2001
). Culturally determined attitudes to suicide, drinking behaviour, help-seeking behaviour, and the availability of health care services are some factors that will determine mortality (both natural and unnatural) in persons with alcohol use disorders.
The finding that alcohol use disorder is a significant predictor of suicide risk also in women was somewhat unexpected. Community studies of completed suicides consistently show lower rates of alcohol use disorders in women than in men. While a retrospective diagnosis of alcoholism was demonstrated in over half (56%) of mixed aged male suicides in Stockholm (Beskow, 1979), such a diagnosis was observed in only 15% of female suicides from the same setting (Åsgård, 1990
). A recent register study failed to show an association between alcohol dependence and suicide in women of mixed ages (Baxter and Appleby, 1999
). However, such studies will miss individuals who seek care outside the psychiatric sector. An advantage of the current approach is that persons with alcohol problems can be identified regardless of health care utilization.
The loss of a close interpersonal relationship has been shown to be more common among suicides with alcoholism than among those without (Berglund and Öjehagen, 1998; Murphy, 2000
). Recent loss due to separation was uncommon in our study. One reason for this disparity might be that we are dealing specifically with the elderly. Many of the alcoholics in our study suffered separations earlier in life and now had nothing left to lose. This is in line with the Carney et al.(1994)
finding that interpersonal loss was less common among elderly suicide victims than among their younger counterparts. Poor personal economy is another factor reported to be more common among suicides with alcohol use disorder, than in those without (Heikkinen et al., 1994
). Problems with personal finances were uncommon in those both with and without alcohol use disorder in our study. We are dealing with a survival population and risk factors for suicide in younger age groups will not necessarily apply in the oldest segment of the population. Persons with both alcohol use disorder and financial difficulties would be expected to have higher mortality earlier in life.
The proportion with a positive post-mortem screening for ethanol in our study (29%) was not unlike that reported for elderly white suicides (21%) in a recent US study (Garlow, 2002). Persons with alcohol use disorder in our study were more likely to use non-violent suicide methods than those without this disorder. This finding, which replicates the work of others (Conwell et al., 1998
), underlines the need for clinicians to be restrictive in prescribing sedatives and hypnotics to this patient group.
Implications for suicide prevention
In conclusion, results from the current study show a strong association between alcohol use disorder and late life suicide in both men and women in this northern European setting. While the number of persons with alcohol dependence and misuse who reach old age is limited, due to increased mortality by both natural and unnatural causes, those who do survive appear to remain at risk for suicide.
![]() |
ACKNOWLEDGEMENTS |
---|
![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() |
---|
![]() |
REFERENCES |
---|
![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() |
---|
Åsberg, M., Montgomery, S. A., Perris, C., Schalling, D. and Sedvall, G. (1978) A comprehensive psychopathological rating scale. Acta Psychiatrica Scandinavica 271 (Suppl.), 527.
Åsgård, U. (1990) A psychiatric study of suicide among urban Swedish women. Acta Psychiatrica Scandinavica 82, 115124.[ISI][Medline]
Barraclough, B. M. (1971) Suicide in the elderly. British Journal of Psychiatry 120 (Special Suppl.), 8797.
Baxter, D. and Appleby, L. (1999) Case register study of suicide risk in mental disorders. British Journal of Psychiatry 175, 322326.[Abstract]
Berglund, M. and Öjehagen, A. (1998) The influence of alcohol drinking and alcohol use disorders on psychiatric disorders and suicidal behavior. Alcoholism: Clinical and Experimental Research 22 (Suppl. 7), 333S345S.[ISI][Medline]
Beskow, J. (1979) Suicide and mental disorder in Swedish men. Acta Psychiatrica Scandinavica 277 (Suppl.), 1138.
Carney, S. S., Rich, C. L., Burke, P. A. and Fowler, R. C. (1994) Suicide over 60: the San Diego Study. Journal of the American Geriatrics Society 42, 174180.[ISI][Medline]
Clark, D. C. and Clark, S. H. (1993) Suicide among the elderly. In Suicidal Behavior: The State of the Art. Proceedings of the XVI Congress of the International Association for Suicide Prevention, Böhme, K., Freytag, R., Wächtler, C. and Wedler, H. eds, pp. 161164. Roderer, Regensburg.
Conner, K. R., Duberstein, P. R. and Conwell, Y. (2001) The validity of proxy-based data in suicide research: a study of patients 50 years of age and older who attempted suicide. I. Psychiatric diagnoses. Acta Psychiatrica Scandinavica 104, 204209.[CrossRef][ISI][Medline]
Conwell, Y. and Brent, D. (1995) Suicide and aging. I: Patterns of psychiatric diagnosis. International Psychogeriatrics 7, 149164.[Medline]
Conwell, Y., Olsen, K., Caine, E. D. and Flannery, C. (1991) Suicide in later life: psychological autopsy findings. International Psychogeriatrics 3, 5966.[Medline]
Conwell, Y., Duberstein, P. R., Cox, C., Herrmann, J. H., Forbes, N. T. and Caine, E. D. (1996) Relationships of age and axis I diagnoses in victims of completed suicide: a psychological autopsy study. American Journal of Psychiatry 153, 10011008.[Abstract]
Conwell, Y., Duberstein, P. R., Cox, C., Herrmann, J., Forbes, N. and Caine, E. D. (1998) Age differences in behaviors leading to completed suicide. American Journal of Geriatric Psychiatry 6, 122126.
Conwell, Y., Lyness, J. M., Duberstein, P., Cox, C., Seidlitz, L., DiGiorgio, A. and Caine, E. D. (2000) Completed suicide among older patients in primary care practices: a controlled study. Journal of the American Geriatrics Society 48, 2329.[ISI][Medline]
Foster, T., Gillespie, K. and McClelland, R. (1997) Mental disorders and suicide in Northern Ireland. British Journal of Psychiatry 170, 447452.[Abstract]
Garlow, S. J. (2002) Age, gender and ethnicity differences in patterns of cocaine and ethanol use preceding suicide. American Journal of Psychiatry 159, 615619.
Harwood, D., Hawton, K., Hope, T. and Jacoby, R. (2001) Psychiatric disorder and personality factors associated with suicide in older people: a descriptive and casecontrol study. International Journal of Geriatric Psychiatry 16, 155165.[CrossRef][ISI][Medline]
Heikkinen, M. E., Aro, H. M., Henriksson, M. M., Isometsä, E. T., Sarna, S. J., Kuoppasalmi, K. I. and Lönnqvist, J. K. (1994) Differences in recent life events between alcoholic and depressive nonalcoholic suicides. Alcoholism: Clinical and Experimental Research 18, 11431149.[ISI][Medline]
Henriksson, M. M., Marttunen, M. J., Isometsä, E. T., Heikkinen, M. E., Aro, H. M., Kuoppasalmi, K. I. and Lönnqvist, J. K. (1995) Mental disorders in elderly suicide. International Psychogeriatrics 7, 275286.[Medline]
Hocking, L. B., Koenig, H. G. and Blazer, D. G. (1995) Epidemiology and geriatric psychiatry. In Textbook in Psychiatric Epidemiology, Tsuang, M. T., Tohen, M. and Zahner, G. E. P. eds, pp. 437452. John Wiley and Sons, New York, NY.
Inskip, H. M., Harris, E. C. and Barraclough, B. (1998) Lifetime risk of suicide for affective disorder, alcoholism and schizophrenia. British Journal of Psychiatry 172, 3537.[Abstract]
Miller, M. D., Paradis, C. F., Houck, P. R., Mazumdar, S., Stack, J. A., Rifai, A. H., Mulsant, B. and Reynolds, C. F., III (1992) Rating chronic medical burden in geropsychiatric practice and research: application of the Cumulative Illness Rating Scale. Psychiatry Research 41, 237248.[CrossRef][ISI][Medline]
Murphy, G. E. (2000) Psychiatric aspects of suicidal behaviour: substance abuse. In The International Handbook of Suicide and Attempted Suicide, Hawton, K. and van Heeringen, K. eds, pp. 135146. John Wiley and Sons, Chichester.
Paykel, E. S., Myers, J. K., Dienalt, M. N., Klerman, G. L., Lindenthal, J. J. and Pepper, M. P. (1969) Life events and depression: a controlled study. Archives of General Psychiatry 21, 753760.[CrossRef][ISI][Medline]
Ramstedt, M. (2001) Alcohol and suicide in 14 European countries. Addiction 96 (Suppl. 1), S59S75.[ISI][Medline]
Regier, D. A., Myers, J. K., Kramer, M., Robins, L. N., Blazer, D. G., Hough, R. L., Eaton, W. W. and Locke, B. Z. (1984) The NIMH Epidemiologic Catchment Area program: historical context, major objectives, and study population characteristics. Archives of General Psychiatry 41, 934941.[Abstract]
Rich, C. L., Young, D. and Fowler, R. C. (1986) San Diego suicide study: I. Young vs old subjects. Archives of General Psychiatry 43, 577582.[Abstract]
Runeson, B. (1990) Psychoactive substance use disorder in youth suicide. Alcohol and Alcoholism 25, 561568.[ISI][Medline]
Skoog, I., Nilsson, L., Landahl, S. and Steen, B. (1993) Mental disorders and the use of psychotropic drugs in an 85-year-old urban population. International Psychogeriatrics 5, 3348.[Medline]
Waern, M., Runeson, B. S., Allebeck, P., Beskow, J., Rubenowitz, E., Skoog, I. and Wilhelmsson, K. (2002) Mental disorder in elderly suicides: a casecontrol study. American Journal of Psychiatry 159, 450455.
World Health Organization (1977) Manual of the International Statistical Classification of Diseases, Injuries and Causes of Death, Ninth Revision (ICD-9). World Health Organization, Geneva.