Dementia and suicidal behavior: a review of the literature

While dementia is more common in older people and suicide rates in many countries are higher among the elderly, there is some doubt about the association between these two phenomena.

A search of the major relevant databases was carried out to examine the evidence for this possible association.

The association between dementia and suicide and also non-fatal self-harm did not appear strong but many studies have significant methodological limitations and there are few studies of suicide or self-harm in vascular, frontotemporal, Lewy body and HIV dementia where such behavior might be expected to be more common. Rates of self-harm may be increased in mild dementia and are higher before than after predictive testing for Huntington's disease. Overall, the risk of suicide in dementia appears to be the same or less than that of the age-matched general population but is increased soon after diagnosis, in patients diagnosed with dementia during hospitalization and in Huntington's disease. Putative risk factors for suicide in dementia include depression, hopelessness, mild cognitive impairment, preserved insight, younger age and failure to respond to anti-dementia drugs. Large, good quality prospective studies are needed to confirm these findings.

Further research should be undertaken to examine how rates of suicide and self-harm change during the course of the illness and vary according to the specific sub-type of dementia.