Another study has found that the use of antipsychotic drugs increases the risk of death when used to treat disruptive behavior of older adults with dementia.

The study, to be published in the Annals of Internal Medicine, suggests that both newer "atypical" antipsychotics and older conventional antipsychotics are associated with increased mortality.

Antipsychotic drugs are typically used treating psychotic conditions, such as schizophrenia and mania. But they are also widely prescribed to manage behavioral symptoms of dementia, such as aggression, delusions, hallucinations or paranoia.

The FDA and Health Canada both issued warnings in 2005 that use of newer atypical antipsychotics in elderly patients with dementia was associated with an increased risk of death. But previous studies have generally been short and did not provide information about the long-term impact of antipsychotics on death.

Investigators, funded in part by the Ontario Ministry of Health and Long-Term Care, looked at health and death records of more than 27,000 people in Ontario age 66 and older diagnosed with dementia between April 1, 1997, and March 31, 2002. They looked at both seniors who lived in the community as well as those who lived in long-term care facilities.

Use of newer "atypical" antipsychotic medications was associated with an increased risk of death at 30 days, relative to no antipsychotics use in both community-dwelling seniors and long-term care residents.

At 180 days, mortality was nine per cent among atypical antipsychotic users and eight per cent among non-users in the community-dwelling group. In long-term care residents, mortality at 180 days was 17 per cent among atypical antipsychotic users and 15 per cent among non-users.

The use of typical antipsychotics was associated with an even greater risk of death than atypical antipsychotics, again with the risk evident at 30 days and persisting to 180 days.

In the community-dwelling group, mortality at 180 days was 13 per cent among typical antipsychotic users and 11 per cent among atypical antipsychotic users. In the long-term care residents, mortality at 180 days was 20 per cent among typical antipsychotic users and 18 per cent among atypical antipsychotic users.

"Although these numbers may at first not appear that dramatic, the severity of the outcome and the relatively short follow-up time of 30 days to six months means that even increases of one or two per cent are highly significant and clinically important, especially when considering that for many elderly dementia patients these medications may not be very beneficial," said Dr. Sudeep Gill, a geriatric medicine specialist and the study's lead author.