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Seniors suffering with dementia benefiting from pills? Troubling prescribing trends: ICES study


A diagnosis of Alzheimer’s disease is daunting. It’s the most common form of dementia, a progressive degenerative disease of the brain which causes thinking and memory to become seriously impaired. Affecting some 200,000 Canadians over the age of 65, there is no cure. The medications available to treat symptoms, may not be used appropriately says new research from the Institute for Clinical Evaluative Sciences (ICES).

The ICES study published in the Journal of the American Geriatrics Society looked at nearly 29,000 older adults in the province of Ontario who received drugs called cholinesterase inhibitors (ChEIs). The only approved treatment for Alzheimer disease (AD) in Canada, ChEIs help ease symptoms by slowing down the decline of memory, language and thinking abilities. There are three CHEIs (donepezil, rivastigmine, galantamine) and patients who received a new prescription for a ChEI were followed between June 2000 – December 2002 until discontinuation of ChEI therapy or death. The study was designed to examine how long ChEI treatment persisted, whether patients remained on these drugs after institutionalization, how many switched from one ChEI to another and how many were treated until death. The results:

  • Doctors who prescribe ChEIs may be keeping their patients on the drugs beyond the point where they continue to be effective
  • Patients who lived in long term care at the start of ChEI therapy were treated for an average of 1021 days compared to 823 days for individuals residing in the community
  • Switching to another ChEI occurred more commonly in patients living in the community 6.7% vs. long term care at 4.9%
  • Of the 35% of patients who died during the observation period more than half were still taking a ChEI at time of death
  • Only a quarter of these patients had seen a consultant with specialized knowledge in dementia diagnosis within the 60 day span.

Dr. Nathan Herrmann, lead author and head, Division of Psychiatry from Sunnybrook Health Sciences Centre says “this study is very important because it is the first population-based study of anti-dementia drug utilization in Canada. The most notable finding is that while the trials, on the basis of which these drugs were approved, were mostly of 6 month duration, in practice, these drugs are being used for very lengthy period of times, greater than two years and often until death. These findings raise important questions about appropriateness of use and whether there is a real cost-benefit to their lengthy use.”

Prescriptions and drug expenditures for ChEIs have increased dramatically since their introduction to the seniors’ universal coverage in Ontario. According to the ICES study, the prevalence of ChEI use increased by 1500% between 1999 -2002 and accounted for 25% of the mental health drug costs in 2002, while representing less than 6% of mental health related drug prescriptions. Dr. Paula Rochon, senior author and ICES scientist says, “These drugs were not intended to be prescribed indefinitely to patients with dementia. There comes a point in the disease progression when being on a cholinesterase inhibitor is no longer beneficial.”

The study “A population-based study of cholinesterase inhibitor utilization for dementia” is in the October issue of Journal of the American Geriatrics Society.

Dr. Paula Rochon is also a scientist with Baycrest in Toronto, Ontario.

Author affiliations: ICES (Drs. Gill, Bell, Anderson, Bronskill, Fischer, Rochon, Mr. Shi and Ms. Sykora), Toronto, Ontario; Department of Psychiatry, Sunnybrook Health Sciences Centre (Drs. Herrmann, Shulman); University of Toronto(Drs. Herrmann, Bell, Anderson, Bronskill, Shulman, Rochon), Toronto, Ontario; Departments of Medicine and Community Health and Epidemiology, Queen’s University (Dr. Gill), Kingston, Ontario; Department of Medicine, St Michael’s Hospital (Dr. Bell), Toronto, Ontario; Kunen-Lunenfeld Applied Research Unit, Baycrest (Dr. Rochon), Toronto, Ontario.

ICES is an independent, non-profit organization that uses population-based health information to produce knowledge on a broad range of healthcare issues. Our unbiased evidence provides measures of health system performance, a clearer understanding of the shifting healthcare needs of Ontarians, and a stimulus for discussion of practical solutions to optimize scarce resources. ICES knowledge is highly regarded in Canada and abroad, and is widely used by government, hospitals, planners, and practitioners to make decisions about care delivery and to develop policy.


  • Kristine Galka
  • Media Relations, ICES
  • Office: 416-480-4780 or Cell: 416-629-8493
  • [email protected]


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