Elsevier

Biological Psychiatry

Volume 52, Issue 3, 1 August 2002, Pages 193-204
Biological Psychiatry

Risk factors for suicide in later life

https://doi.org/10.1016/S0006-3223(02)01347-1Get rights and content

Abstract

Suicide rates are higher in later life than in any other age group. The design of effective suicide prevention strategies hinges on the identification of specific, quantifiable risk factors. Methodological challenges include the lack of systematically applied terminology in suicide and risk factor research, the low base rate of suicide, and its complex, multidetermined nature.

Although variables in mental, physical, and social domains have been correlated with completed suicide in older adults, controlled studies are necessary to test hypothesized risk factors. Prospective cohort and retrospective case control studies indicate that affective disorder is a powerful independent risk factor for suicide in elders. Other mental illnesses play less of a role. Physical illness and functional impairment increase risk, but their influence appears to be mediated by depression. Social ties and their disruption are significantly and independently associated with risk for suicide in later life, relationships between which may be moderated by a rigid, anxious, and obsessional personality style.

Affective illness is a highly potent risk factor for suicide in later life with clear implications for the design of prevention strategies. Additional research is needed to define more precisely the interactions between emotional, physical, and social factors that determine risk for suicide in the older adult.

Introduction

In May 2001 the Office of the Surgeon General of the United States released the National Strategy for Suicide Prevention: Goals and Objectives for Action (U.S. Public Health Service 2001). The prevention of suicide in later life is a central objective of that strategy. Older adults are at higher risk for suicide than any other age group. They are also the fastest growing segment of the population. Individuals born in the post-World War II “baby boom” have carried with them substantially higher suicide rates than preceding or subsequent birth cohorts (Blazer et al 1986). As large numbers of this high-risk cohort enter later life in coming decades, therefore, the absolute number of seniors who take their own lives may rise dramatically (Haas and Hendin 1983). We must be prepared to intervene.

The design of effective suicide prevention strategies hinges on the definition and quantification of risk and protective factors for suicide in the target population of older adults. Our objective with this paper is to evaluate the strength of the evidence for whether correlates of suicide in each of three broad domains-mental health, physical health, and social factors-constitute risk factors for suicide in later life. We begin with consideration of methodological issues that pose challenges for the definition of suicide risk and protective factors in older adults. We then provide a brief overview of the prevalence of suicidal behaviors-suicidal ideation (SI), attempted suicide (AS), and completed suicide (CS)- in U.S. seniors. In the remainder of the paper we focus primarily on observed correlates of CS in later life, emphasizing the evidence derived from a recent series of retrospective, case control, psychological autopsy studies. The conclusion to which they lead is that affective illness (its prevention, early recognition, effective diagnosis, and aggressive treatment) should be the leading target of later life suicide prevention efforts.

Section snippets

Methodologic issues

A number of methodologic issues complicate the study of suicide in later life. First, the terms used in the literature and clinical settings to describe suicidal behavior are often ill defined and loosely applied, making the interpretation and generalization of findings difficult. As well, SI, AS, CS are often conflated in discussions of suicidal behavior, leading to an inaccurate understanding of risk. Consensus on a precise typology of aggressive and self-destructive behaviors has been

Suicidal ideation

Older adults are less likely to endorse suicidal ideation than are younger subjects Gallo et al 1994, Blazer et al 1986, Duberstein et al 1999. Estimates of the prevalence of suicidal ideation in older adults vary widely. Lish and colleagues found that 7.3% of an older sample in VA primary care practices had suicidal ideation, with rates seven times higher in patients with a history of mental health treatment (Lish et al 1996). Using a more stringent criterion set for suicidal ideation (within

Risk factors for suicide in older adults

In the following sections we review evidence for later life suicide risk factors in three broad domains - mental health, physical health, and social function. Each section provides a brief overview of descriptive studies that were important in the characterization of elders at risk for suicide. Our emphasis, however, is on the small number of PA studies that meet (with varying degrees of success) rigorous methodological standards for evaluating risk (Kraemer et al 1997).

Access to means

Older adults tend to use more immediately lethal methods for suicide than do younger age groups. In 1998, for example, 57% of suicides in the United States were committed with a firearm (62% of men and 39% of women) (Murphy 2000). Seventy-one percent of elderly suicide victims, however, used guns. Brent and colleagues demonstrated that the presence of a firearm in the home was a significant risk factor for suicide among adolescents regardless of whether the weapon was stored in a secure place,

Summary and implications

Demographic characteristics associated with elevated risk for suicide are better termed “fixed markers” because they are immutable (Kraemer et al 1997). These include older age, male gender, and white race. Epidemiologic studies provide strong evidence that unmarried conjugal status confers risk for suicide as well.

Table 4 lists risk factors for suicide in older adults in mental health, physical health, and social domains that are derived from statistical testing of multivariate models in

Acknowledgements

This work was supported in part by NIMH K24 MH01759 (Dr. Conwell).

Aspects of this work were presented at the conference, “Unmet Needs in Diagnosis and Treatment of Mood Disorders in Late Life,” October 9–10, 2001 in Washington, DC. The conference was sponsored by the National Depressive and Manic-Depressive Association (National DMDA) through unrestricted educational grants provided by Abbott Laboratories, AstraZeneca, Forest Laboratories, GlaxoSmithKline, Janssen Pharmaceutica, Eli Lilly and

References (70)

  • I.R.C. Batchelor et al.

    Attempted suicide in old age

    Br Med J

    (1953)
  • A.L. Beautrais

    A case control study of suicide and attempted suicide in older adults

    Suic Life-Threaten Behav

    (2002)
  • D.G. Blazer et al.

    Suicide in late lifeReview and commentary

    J Am Geriatr Soc

    (1986)
  • D.A. Brent et al.

    The validity of diagnoses obtained through the psychological autopsy procedure in adolescent suicide victimsUse of family history

    Acta Psychiatr Scand

    (1993)
  • D.A. Brent et al.

    Firearms and adolescent suicide. A community case-control study

    Am J Dis Children

    (1993)
  • J.H. Brown et al.

    Is it normal for terminally ill patients to desire death?

    Am J Psychiatry

    (1986)
  • C.M. Callahan et al.

    Suicidal ideation among older primary care patients

    J Am Geriatr Soc

    (1996)
  • S.S. Carney et al.

    Suicide over 60The San Diego study

    J Am Geriatr Soc

    (1994)
  • H.M. Chochinov et al.

    Desire for death in the terminally ill

    Am J Psychiatry

    (1995)
  • D.C. Clark

    Suicide among the elderly. Final report to the AARP Andrus Foundation

    (1991)
  • D.C. Clark

    Narcissistic crises of aging and suicidal despair

    Suic Life-Threaten Behav

    (1993)
  • D.C. Clark et al.

    Assessment in absentiaThe value of the psychological autopsy method for studying antecedents of suicide and predicting future suicides

  • D. Cohen et al.

    Homicide-suicide in older persons

    Am J Psychiatry

    (1998)
  • K. Conner et al.

    The validity of proxy-based data in suicide researchA study of patients 50 years of age and older who attempted suicide. II. Life events, social support and suicidal behavior

    Acta Pscyhiatr Scand

    (2001)
  • K. Conner et al.

    The validity of proxy-based data in suicide researchA study of patients 50 years of age and older who attempted suicide. I. Psychiatric diagnoses

    Acta Pscyhiatr Scand

    (2001)
  • Y. Conwell et al.

    Suicide and aging. IPatterns of psychiatric diagnosis

    Int Psychogeriatr

    (1995)
  • Y. Conwell et al.

    Relationships of age and axis I diagnoses in victims of completed suicideA psychological autopsy study

    Am J Psychiatry

    (1996)
  • Y. Conwell et al.

    Completed suicide among older patients in primary care practicesA controlled study

    J Am Geriatr Soc

    (2000)
  • Y. Conwell et al.

    Suicide in later lifePsychological autopsy findings

    Int Psychogeriatr

    (1991)
  • Y. Conwell et al.

    Completed suicide at age 50 and over

    J Am Geriatr Soc

    (1990)
  • P.T. Costa et al.

    Revised NEO Personality Inventory and NEO Five Factor InventoryProfessional Manual

    (1992)
  • T.L. Dorpat et al.

    The relationship of physical illness to suicide

  • P.R. Duberstein et al.

    Age differences in the personality characteristics of suicide completersPreliminary findings from a psychological autopsy study

    Psychiatry

    (1994)
  • N.L. Farberow et al.

    Suicide among patients with malignant neoplasms

  • J.J. Gallo et al.

    Age differences in the symptoms of depressionA latent trait analysis

    J Gerontol

    (1994)
  • Cited by (544)

    • Multimodal Neural Evidence on the Corticostriatal Underpinning of Suicidality in Late-Life Depression

      2022, Biological Psychiatry: Cognitive Neuroscience and Neuroimaging
    View all citing articles on Scopus
    View full text