Nearly 750,000 people in Canada live with dementia, according to estimates from the Alzheimer Society of Canada. A variety of conditions, including Alzheimer’s disease, can cause dementia-related symptoms such as a decline in memory and cognitive abilities.
In Canada, only four medications are approved to manage dementia. One of the most prescribed drugs, donepezil, has been associated with life-threatening cardiac side effects in some research.
Cristian Garcia, a second-year student in the MD Program at the University of Toronto’s Temerty Faculty of Medicine, is a co-lead author of a systematic review and meta-analysis recently published in the Journal of the American Geriatrics Societythat found no link between the drug and fatal heart arrhythmias.
He spoke with writer Erin Howe about the research and the ecosystem of collaboration at Temerty Medicine.
What excites you most about this paper?
We looked at a drug called donepezil, a medication commonly given to people who have dementias like Alzheimer's to slow the progression of these conditions. The downside is that donepezil has many side effects, including affecting the heart’s rhythm, which can be life-threatening. It’s an extremely uncommon adverse effect, but the concern has made some health care professionals reluctant to prescribe the drug. We wanted to better understand where this concern comes from.
Before we started our review, my collaborators and I suspected that a lot of the research suggesting donepezil causes life-threatening harm was low-quality. For example, a handful of case reports decades ago from people on multiple medications for various medical conditions who died while taking the drug. Is it clear that specifically donepezil contributed to these deaths, amongst so many other factors?
So, we set out to look at the highest-quality evidence from randomized trials, and to find out if being on donepezil makes people more likely to have these life-threatening heart rhythm issues or to die.
We found there was no evidence to support those fears, and while various important side effects remain, these findings may be reassuring for physicians and for people whose family members need this drug.
How did you first become aware of the concerns around this medication?
Before I started the MD Program at Temerty Medicine, I did my master’s degree at McMaster University. My supervisor there and the paper’s senior author,Dr. Anne Holbrook, is a clinical pharmacologist who studies medication safety. She took a closer look at donepezil after she received questions from physicians who wanted to know if they could safely prescribe the medication.
I finished my Master of Science in health research methodology and wanted to continue this work after I began to study medicine.
What is it that makes collaborations like this possible here at Temerty Medicine?
There’s so much freedom here at Temerty Medicine and such a rich network of people doing so many different things within our program. Research is ingrained in the curriculum. We’re empowered to do research, and it’s easy to connect with others who are passionate about the work they do.
That dynamic played out with this research, too. My co-first author, Tina Nham, is a geriatrics fellow at McMaster. She has the clinical research background, and I was able to contribute the methodology and analysis.
What interests you most about geriatrics?
The amount of time that you can spend with your patients appeals to me. I'm doing a home visit with a geriatrician tomorrow, and we're seeing one patient for two hours!
I love the idea that this field allows clinicians to truly get to know people, how their overall health impacts their day-to-day living and quality of life, not just their chief complaint.
In medicine, we have a huge communication toolkit to help us interview patients for different concerns but a lot of the time, we have to be really focused due to time restrictions.
In geriatrics, we can learn everything about a person, how they care for themselves, who helps care for them. It's so holistic.
And that's really what our training here at Temerty Medicine encourages us to do — to look at each patient as a whole, and geriatrics fits this perfectly with this training.
What are the next steps for this research?
We’d like to launch a similar study using hospital data to compare the rates of death and life-threatening cardiac adverse effects for a large list of other commonly prescribed medications. Just like with donepezil, there are a plethora of medications ranging from antibiotics to antinausea agents with a presumed risk of serious cardiac adverse effects, which may be causing unnecessary concern.
What do you like to do in your spare time?
I love going for walks, taking in nature, spending time with my cat Yuki. I also love to read. Fiction is a great escape. I recently read — and loved — The Midnight Library by Matt Haig.
The research study was supported by the Ontario Ministry of Health and Long-Term Care.
