Currently, three ChEIs are
prescribed in Canada: donepezil (Aricept), galantamine (Reminyl), and
rivastigmine (Exelon). The benefits of cholinesterase inhibitors for people
with AD are generally small. The drugs do not reverse the effects of dementia.
However, research suggests that in about half of patients, the drugs delay the
worsening of cognitive decline for between six months to a year. A minority of
patients may benefit more. Side effects of ChEIs include nausea, vomiting,
diarrhea, anorexia, weight loss, dizziness, bradycardia (heart rate of under 60
BPM), myalgias (muscle pain), and insomnia.
It appears that the
cardiovascular toxicity of ChEIs is underappreciated by physicians. At St.
Michael’s hospital in Toronto, the health records of elderly patients were
examined. Researchers concluded that ChEI therapy more than doubles the risk of
hospitalization for bradycardia. Of the
ChEI-bradycardia patients studied, 11% required a pacemaker and 4% died before discharge.
Findings showed that among those patients discharged from hospital more than
half resumed ChEI therapy.
Non-drug therapies for dementia include
cognitive-behavioural interventions, validation therapy, multisensory therapies
such as music and art therapy, and others. Studies of non-drug therapies for dementia have been shown to delay cognitive decline without adverse side-effects, with
studies yielding effect sizes similar to those of ChEIs. These therapies have
also been shown to a) enhance the ability of AD patients to carry out
activities of daily living (housekeeping, meal preparation, eating, personal
hygiene, dressing etc.), and b) enhance the quality of life for both patient and their
primary caregiver. Data show that day-to-day functioning and quality of life are
not enhanced by ChEI medication.
Increasingly, second-generation
antipsychotic medications (or atypical antipsychotics), (originally developed to
treat schizophrenia and other psychoses, have been used in AD to stabilize
mood and reduce anxiety, tension, and hyperactivity, and control agitation and
aggressiveness. Increased use of these drugs has continued despite the known
side-effects and risks, including sedation, higher risks of falls and hip
fractures, tardive dyskinesia (Parkinson's disease-type symptoms),
cardiovascular events (stroke and heart attack), and overall greater risk of
death. In response, Health Canada issued a warning in June, 2005:
"…treatment with atypical antipsychotic medication of behavioral disorders in elderly patients is associated with an increased risk for all-cause mortality. Except for risperidone (RISPERDAL), these medications are not approved for use in elderly patients with dementia."In 2007, the BC Clinical Practice Guideline on Cognitive Impairment in the Elderly recommended environmental, behavioural, and psychosocial interventions as the first line of treatment for behavioural and psychological symptoms of dementia. The Guideline also recommended that physicians exercise caution when prescribing antipsychotic medications for elderly persons with dementia due to their side effects and the increased risk of death. Yet data collected in British Columbia between April 2010 and June 2011 showed that 50.3 percent of residential care patients were prescribed an antipsychotic. The data included 477,765 prescriptions dispensed at a cost of $9.245 million.
Earlier this month, the pharmaceutical company Johnson & Johnson agreed to pay over $2.2 billion to resolve allegations that the company downplayed known side-effects of Risperdal and aggressively marketed its use for seniors, children and the disabled. Other drugs companies have also agreed to pay billions of dollars in response to similar allegations regarding other atypical antipsychotics. A class action suit against Johnson & Johnson is currently underway in Canada (see http://risperdalcanadaclassaction.com/).
References
British Columbia Ministry of
Health. (2011). A review of the use of
antipsychotic drugs in British Columbia residential care facilities. Retrieved
from http://www.health.gov.bc.ca/library/publications/year/2011/use-of-antipsychotic-drugs.pdf
Globe and Mail (November 2013). Johnson & Johnson to pay $2.2-billion to
settle U.S. drug probes. Retrieved from
http://www.theglobeandmail.com/report-on-business/international-business/us-business/johnson-johnson-settles-suit-over-marketing-unapproved-drugs/article15242384/
Graessel1, E., Stemmer, R., Eichenseer, B., Pickel1, S.,
Donath, Kornhuber, J., & Luttenberger, K. (2011). Non-pharmacological,
multicomponent group therapy in patients with degenerative dementia: A 12-month
randomized, controlled trial. BMC
Medicine (9)129. Retrieved from http://www.biomedcentral.com/content/pdf/1741-7015-9-129.pdf
Hagen. B., Armstrong Esther, C.,
Ikuta, R., Williams, R. J., Le Navenec, C., & Aho, M. (2005). Antipsychotic
drug use in Canadian long-term care facilities: prevalence, patterns following
resident relocation. International
Psychogeriatrics, 17(2). Retrieved from
https://www.uleth.ca/dspace/bitstream/handle/10133/378/Antipsychotic_drug_use.pdf%3Fsequence%3D1
Health Canada (2005). Health Canada endorsed important safety
information on atypical antipsychotic drugs and dementia. Retrieved from http://healthycanadians.gc.ca/recall-alert-rappel-avis/hc-sc/2005/14307a-eng.php
Lee, P.E., Hsiung, G. R., Seitz, D., Gill, S. S., &
Rochon, P. A. (2011) Cholinesterase inhibitors. BCMJ 53(8). Retrieved from http://www.bcmj.org/articles/cholinesterase-inhibitors
Park-Wyllie, L. Y., Mamdani, M. M., Li, P., Gill, S. S.,
Laupacis, A., & Juurlink, D. N. (2009). Cholinesterase inhibitors and
hospitalization for bradycardia: A population-based study. PLoS Med (6), 9. Retrieved
from http://www.plosmedicine.org/article/info%3Adoi%2F10.1371%2Fjournal.pmed.1000157
Smith, B., Chur-Hansen, A., Neale, A., & Symon, J. (2008). Quality of life and cholinesterase inhibitors: A qualitative study of patients with Alzheimer's Disease and their carers. Australasian Psychiatry, (16), 6. doi:10.1080/10398560802375990
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