The use of both conventional and atypical antipsychotics to treat dementia in older patients has been linked to an increased the risk of stroke and death. Despite such dangers, a recent Canadian study has found that atypical antipsychotic drugs are increasingly being used to treat elderly patients.
It is estimated that nearly 30 percent of all nursing home patients have received antipsychotic drugs at one time or another. Atypical antipsychotics include drugs like Risperdal, Seroquel, and Zyprexa. Conventional antipsychotics, which are older drugs, include Thorazine, Haldol and others.
In the U.S., both conventional and atypical antipsychotic drugs were approved to treat the symptoms of schizophrenia. They are not approved for use in the treatment of dementia-related symptoms, which can include forgetfulness, poor memory, and an inability to recognize familiar objects, sounds, or people. However, physicians are free to use approved drugs in any way they see fit – a practice known as off-label use.
In June, the U.S. Food & Drug Administration (FDA) asked the makers of conventional antipsychotics to add a black box to their labels warning that the drugs they are associated with an increased risk of death when used in elderly patients to treat dementia-related psychosis. In 2005, the FDA announced similar labeling changes for atypical antipsychotic drugs.
But according to a study conducted by Canadian researchers, those warnings are not being heeded. Between late 2002 and June 2005, Health Canada, the agency in that country that regulates drug safety, issued three warnings that three new atypical antipsychotic drugs increased risk of stroke or death in elderly patients with dementia . Yet, scientist at the University of Toronto found that while use of the drugs to treat dementia declined, their overall use among elderly actually increased during that period.
Their analysis of prescription drug data in the province of Ontario found that antipsychotic drug use among the elderly increased 20 percent from the month prior to the first warning in September 2002 to February 2007. About 70 percent of the seniors receiving antipsychotic drugs lived in nursing homes, and about 40 percent of them were 85 or older.
In an article published in the Canadian Medical Association Journal, Dr. Geoffrey Anderson and coauthors on the study wrote that they “found that the 3 warnings about serious adverse events associated with use of atypical antipsychotic agents in elderly people with dementia had a limited effect on the prescription rates of these agents. We also found that the overall rates of use of these drugs actually increased between the first warning in 2002 and the end of our follow-up in 2007.”
“This finding highlights the limited impact of warnings and suggests that more effective approaches are needed to protect vulnerable populations from potentially hazardous medications,” they wrote.