Main objective: to study the relationship between suicidal thinking and both cognitive impairment and depression.
Design: Random sample selected for interview, all of whom were a cohort in a pre-existing epidemiological study of dementia.
Setting: Community residents.
Patients and other participants: Participants aged over 81. Study excluded the following: moved out of area/died/ too frail/severe communication difficulties/refused interview, refusal by GP/family/carers, 300 names selected at random from database. 170 eligible participants approached: 31 refused, 125 interviewed, 125 informants approached for interview; 118 interviewed.
Main outcome measures: CAMDEX, 15-item Geriatric Depression Scale (GDS), and Scale for Suicidal Ideation (SSI) (including informant versions of latter 2 scales).
Results: 9 people showed suicidal thinking, all women: 6 had clinical evidence of cardiovascular/cerebrovascular disease. Those with suicidal thinking showed higher CAMDEX depression scores, weaker strength of the wish to go on living, higher rates of expressing wish to die and higher rates of depressive illness and mixed DAT/multi-infarct dementia as primary psychiatric diagnoses. No significant associations between suicidal thinking and GDS scores, Alzheimer-type dementia alone, awareness of memory difficulties or severity of dementia.
Conclusions: Results show association between suicidal thinking and both depression and mixed DAT/multi-infarct dementia, but do not support an association between suicidal thinking and awareness of memory problems/severity of dementia. Given the methodological limitations, the significance of the results should be viewed with caution. Further exploration of the role of cerebrovascular disease in depressive disorder is suggested.