Suicide and attempted suicide among older adults in Western Australia

Abstract

Background. Suicide rates are high in later life. Risk factors include male sex and depressive illness. This study investigated the relationship between suicidal behaviour and contact with mental health services among the elderly in Western Australia.

Methods. Record linkage was used to obtain records of hospital admissions and mental health service contacts for all suicide attempts and deaths in the period 1980–95. Standardized incidence ratios were calculated for the elderly, general population and people with mental health service contacts. Cox regression was used to evaluated potential risk factors for elderly people who were in contact with mental health services.

Results. People over 60 years of age accounted for 15% of suicides and 4·6% of attempted suicides. Suicide rates were 3·3 times higher in males and 4·4 times higher in females when compared to the general population of elderly people. For attempted suicide, the rate was 5·8 times higher in males and 6·6 times higher in females with prior contact with mental health services. Highest risk of suicide was found in patients with diagnoses of affective psychoses (RR = 3·7), adjustment reaction (RR = 3·2) or depressive disorder (RR = 2·8). The diagnosis of cancer was associated with decreased risk of suicide (RR = 3·6) and attempted suicide (RR = 1·9).

Conclusions. Suicide rates are high among the elderly in Western Australia. Suicide is significantly associated with the diagnosis of mood disorder. Suicide attempts are less common, and are associated most strongly with mood and personality disorders. The decreased risk of self-harm behaviour among patients with cancer warrants further investigation.