Some say ignorance is bliss. But when it comes to knowing your risk factor for a brain condition like Alzheimer’s disease, would you want to know?
Alzheimer’s is a brain disease that causes a decline in memory, thinking and reasoning skills; it accounts for 60-80 per cent of dementia cases (dementia is a term for the group of symptoms). According to Dementia Australia, there are more than 400,000 Australians currently living with dementia. Without a medical breakthrough, the number of people with dementia is expected to increase to over 800,000 by 2058.
Alzheimer’s disease is caused when a protein called beta-amyloid builds up in the brain forming sticky plaques, which can cause brain cells to die, resulting in loss of function and memory. It isn’t known for certain why some develop it and others don’t.
Once symptoms have started, they are irreversible. However, there are steps we can take to minimise our risk of developing Alzheimer’s later in life. And with Alzheimer’s disease having a period of up to 20 years before the first clinical symptoms emerge, lifestyle changes you make now could alter your path.
A genetic test can reveal whether you are at a higher risk of developing the disease, but should you consider getting it? And
are there better ways to empower yourself against the onset of this disease?
The Hemsworth effect
Genetic testing for Alzheimer’s is complex and can only indicate risk factor. These tests look for single-gene changes, such as the presence of the APOE4 gene. APOE4 isn’t an everyday term, but you might have spotted it in your newsfeed over the past year. In late 2022, it was revealed the actor Chris Hemsworth discovered he had two copies of the APOE4 gene while undergoing genetic tests for filming his National Geographic series, Limitless.
Associate Professor Michelle Lupton is a Queensland-based senior research officer at QIMR Berghofer Medical Research Institute; her main area of expertise is genetics of Alzheimer’s disease. According to Michelle, Alzheimer’s is caused by
a range of factors. Around 60 per cent of this is due to our genetic make-up and the rest is our environment.
She explains that the Apolipoprotein E (APOE) gene comes in three variations in humans: E2, E3 and E4. Everyone has two copies of the APOE gene; they can be two of the same or a mix. “If you inherit the [APO]E4, then you have a higher risk of Alzheimer’s disease,” Michelle says. “People with one copy have about a three times higher risk; people with two copies would have about a 14 times greater risk of Alzheimer’s disease.” However, this does not guarantee you will develop it — you just have an increased risk compared to the general population.
To test or not to test?
Many experts agree that if you don’t have dementia symptoms, testing isn’t recommended. This is because it can cause unnecessary anxiety and without a treatment available, it doesn’t offer any valuable benefit.
Dr Ginni Mansberg is a Sydney-based GP and author of Save your Brain — simple steps and proven strategies to reduce your risk of cognitive decline — before it’s too late. “At the moment, getting the test isn’t recommended. That’s because it’s not a one-way ticket to a nursing home,” says Ginni. “In fact, 24 per cent of people seem to carry at least one of the [APOE4 gene]. Not all will get dementia. Plus, it wouldn’t change our advice about how to live your life now to reduce your risk of developing dementia … if we get a really good treatment for dementia, especially in [APOE4] carriers, that would be a game changer and the test would be 100 per cent worth doing.”
But for Renée Brack, getting tested was the motivation for making healthier lifestyle changes. After losing her father to dementia, Renée embarked on her social impact documentary Ticketyboo: A Secret in Plain Sight and underwent testing for dementia on screen. For the purpose of her documentary, Renée did further cognitive tests and an MRI scan of her brain, tests that aren’t usually done unless someone displays symptoms. Through the test, Renée learned that she has a higher chance of developing Alzheimer’s disease.
Renée doesn’t regret getting the test done as it motivated her to make healthy lifestyle changes. She now does yoga regularly and has significantly reduced her alcohol consumption, as well as eating a healthier diet, limiting sugary “treats” to once a week instead of once a day. Renée has also found comfort in support groups on social media and recommends researching these if you have an interest in the test.
Maintain your brain
According to dementia experts, preventative measures are considered more empowering and productive than getting tested. This starts with keeping our brain active. Honorary medical advisor at Dementia Australia, Professor Michael Woodward AM, says you should start exercising your brain as early as you can. “Certainly, from our 40s, because there’s evidence that the amyloids [plaques that cause brain cell death] start accumulating in late 40s, early 50s,” he says.
Our brain starts to degenerate after the age of 30, so take conscious steps to keep your hippocampus — the memory region of your brain — active. Consider taking evening classes to learn a new skill, such as language learning, playing a musical instrument or join a book club. And learning new skills doesn’t need to be costly; you can teach yourself to knit, paint or cook by watching YouTube tutorials at home. When you learn something new, you build new neural pathways and strengthen the ones that already exist.
And don’t let your smart phone replace your brain. Try doing basic maths calculations in your head instead of immediately reaching for your phone, or try navigating your way to your destination using your memory instead of Google Maps. Do something each day that will exercise your brain and stimulate it, rather than seeking the easy option.
Healthy body, healthy mind
Take care of your body as well as your mind to minimise your risk of developing Alzheimer’s. “Make sure that you get enough exercise,” says Michael, “at least 40 minutes, five times a week. Eat a Mediterranean-style diet of green, leafy vegetables, enough protein from white meat such as fish and not too much dessert.”
Michael also highlights that being engaged in social activities is key. Stay connected and engaged with family, friends, the community, and avoid being socially isolated for extended periods of time.
Prioritise shuteye and aim to get six to eight hours of undisrupted sleep each night. “A 2017 meta-analysis of 27 studies found that sleep problems raise the risk of cognitive impairment by 65 per cent, and that poor-quality sleep could explain up to 15 per cent of Alzheimer’s disease cases,” says Ginni.
Maintain healthy blood pressure, don’t smoke, and address mental health concerns like depression as this can negatively impact your brain health. Getting regular health check-ups is also important, particularly from 40 onwards, when other health issues like high blood pressure, thyroid issues, diabetes and depression increase, all of which have been linked to cognitive decline and Alzheimer’s disease. According to Dementia Australia, adults with Type 2 diabetes have a higher risk of developing Alzheimer’s.
The path forward
Treatment for Alzheimer’s disease is on the horizon, with promising steps being taken in the development of anti-amyloid drugs. “I think in the next five to 10 years, there will be approved drugs in Australia that may be a treatment for early-stage Alzheimer’s disease,” says Michelle. These aren’t a magic cure but may help delay the onset of the disease.
Ultimately, whether to get tested is your decision. However, make sure you do your research through reputable organisations like Dementia Australia and speak to your GP. The advice from many experts is to not get tested, but to live as healthy a life as you can. “The only advantage the genetic test might have is that you start living your life in a way you should be living it anyway,” says Michael.
Chris Hemsworth is of a similar opinion. After discovering his diagnosis of having two APOE4 genes, Chris says, “The prescription is simple. Eat and sleep well. Challenge my mind and body with new experiences and immerse myself in nature away from the distractions and stress of modern life. And crucially, share all of this with the people I love.”
Jo Jukes is a British-born freelance writer based in Sydney. She loves waking up to the sound of the ocean and writes about travel, health and wellbeing. Find her on Instagram @what_joey_did_next
Lifestyle changes you can make to lower your risk of developing Alzheimer’s disease
– Keep learning: Keep the memory region of your brain stimulated by learning something new, take an evening class in learning
a language or cooking.
– Stay social: Make regular time for social interaction, even if it’s only on Zoom or the phone. Set a coffee or lunch date with a friend once a week.
– Eat healthy: A healthy balanced diet like a Mediterranean diet is recommended — whole grains, green leafy vegetables, healthy fats like olive oil, and lean protein.
– Get physical: Get at least 40 minutes of aerobic exercise, five times per week.
– Sleep well: Sleep is what helps flush toxins out of your brain and plays a critical role in beta-amyloid clearance.
– Check-in: Go for regular check-ups with your GP to identify health conditions that may put you at a higher risk of developing Alzheimer’s (high blood pressure, diabetes, depression etc).
