Three regulatory warnings of serious adverse events slowed the growth of use of atypical antipsychotic drugs among elderly patients with dementia, but they did not reduce the overall prescription rate of these drugs, found a research analysis of prescription drug claims data in Ontario.
The rate of use of these drugs actually increased 20% from the month prior to the first warning in September 2002 to the end of the study period in February 2007.
About 70% of people receiving antipsychotic drugs lived in nursing homes, and approximately 40% were aged 85 or older.
Three new atypical antipsychotic drugs approved for the treatment of schizophrenia and other related psychiatric conditions by Health Canada, however only one of them was approved for short term use to treat symptoms of aggression and psychosis in elderly patients with dementia. Between October 2002 and June 2005 Health Canada released three warning of increased risk of stroke or death in elderly patients with dementia taking these drugs.
Dr. Geoffrey Anderson and coauthors "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," state the authors.
Some healthcare warnings fail to achieve the desired effect because the warnings have not provided physicians with information about the effectiveness and safety of alternative treatment options, writes Dr. Laurence Katz in a related commentary. He states that health care warnings need to provide complete information about the risks and efficacy of the treatment and should identify alternative treatments.
- Valiyeva et al. Effect of regulatory warnings on antipsychotic prescription rates among elderly patients with dementia: a population-based time-series analysis. Canadian Medical Association Journal, 2008; 179 (5): 438 DOI: 10.1503/cmaj.071540
Cite This Page: