Risk of stroke and increased risk of mortality in elderly patients treated for dementia.
Use of Antipsychotic Medicines in the Elderly with Dementia
To date, just one antipsychotic medicine, risperidone has been authorised in Ireland for short-term (up to 6 weeks) treatment of persistent aggression in Alzheimer’s dementia, unresponsive to non-pharmacological approaches and where there is a risk of harm to the patient or others.
Risk of stroke
The IMB previously advised of a clear increase in the risk of stroke with use of the atypical antipsychotics risperidone and olanzapine in elderly people with dementia (approximately three-times increased risk compared with placebo). It also advised that this risk of stroke could not be excluded for other antipsychotics (atypical or typical), and the product information for all antipsychotics was updated to include a class warning1. At that time an analysis of 17 placebo-controlled trials found that atypical antipsychotics are associated with increased mortality when used in elderly people with dementia (a 1–2% increased risk compared with no treatment) 2. For risperidone, there is an additional increase in the risk when co-prescribed with frusemide.
More recently (November 2008), the Scientific Committee of the European Medicines Agency, the Committee for Human Medicinal Products (CHMP) considered a review of published epidemiological studies looking at the risk of death associated with the use of conventional antipsychotics in elderly people with dementia 2,3,4. The CHMP concluded that the currently available data suggest that conventional (typical) antipsychotics are likely to be associated with increased mortality when used in elderly people with dementia and, although some of the studies suggest that the excess mortality observed with conventional antipsychotics may be greater than that observed for the newer atypical antipsychotics, this could not be confirmed due to the methodological limitations of these studies4. No conclusion could be drawn as to whether the risk differs between individual antipsychotics within the class of conventional antipsychotics and therefore, until and unless better evidence becomes available, it cannot be excluded that the increased risk applies to all products of the class. At present, there is no clear mechanistic basis for the observed increased risk of death.
In light of the results of the review, CHMP recommended that the product information for all conventional antipsychotics authorised for use in the EU should be modified to include information on the increased risk of mortality when used in elderly people with dementia.
Risperidone
In the case of persistent aggression in moderate to severe Alzheimer’s disease, where the patient puts themselves or others at risk of harm, short-term treatment with risperidone may be indicated if the behaviour has not responded to non-pharmacological means. A new analysis of three randomised controlled trials5–8 conducted in elderly patients with behavioural problems showed a clear benefit for the short-term use of risperidone when aggression only was considered. The balance of risks and benefits for risperidone used to treat behavioural disturbances in dementia is only considered to be positive within its narrow licensed indication: i.e. short-term use for persistent aggression in Alzheimer’s-type dementia.
Advice for healthcare professionals
• There is a clear increased risk of stroke and a small increased risk of death when antipsychotics (typical or atypical) are used in elderly people with dementia.
• The balance of risks and benefits associated with risperidone treatment should be carefully assessed for every patient, taking into consideration the known increased mortality rate associated with antipsychotic treatment in the elderly.
• Prescribers should carefully consider the risk of cerebrovascular events before treating any patient who has a previous history of stroke or transient ischaemic attack with risperidone. Consideration should also be given to other risk factors for cerebrovascular disease including hypertension, diabetes, smoking, and atrial fibrillation.
1- IMB Drug Safety Newsletter, June 2004
2- US FDA Public Health Advisory. Deaths with antipsychotics in elderly patients with behavioural disturbances, April 11 2005.
http://www.fda.gov/cder/drug/advisory/antipsychotics.htm (accessed March 25, 2009).
3- Schneeweiss S, et al. CAMJ 2007; 176: 627–32.
4- Gill SS, et al. Ann Intern Med 2007; 146: 775–86.
5- Statement from the European Medicines Agency at
http://www.emea.europa.eu/pdfs/human/opiniongen/Conventional_Antipsychotics_Article5.3-CHMP_Opinion.pdf and accompanying report and question-and-answer document.
6- Katz IR, et al. J Clin Psychiatry 1999; 60: 107–15.
7- De Deyn PP, et al. Neurology 1999; 53: 946–55.
8- Brodaty H, et al. J Clin Psychiatry 2003; 64: 134–43.