A Head Start
Between our head and shoulders, knees and toes, reducing our dementia risk may be in taking care of our eyes, ears, mouth and nose
“Everything we do revolves around good functioning vision,” explains Dr. Regan Nowlan, an optometrist in Calgary. When people age and become less physically able due to decreased mobility, they become more reliant on visual activities like reading and seeing loved ones. When their vision is compromised, they are less able to participate in these activities. This can result in isolation and depression, which may increase the odds of developing dementia.
One eye condition that is particularly impactful is age-related macular degeneration (AMD). When the tiny, oval-shaped macula in the retina begins to deteriorate, central vision disappears, leaving only sight in the margins. “If you lose your central vision — what you use to read, to drive, to function — the loss is significant,” says Nowlan.
AMD accounts for 90 per cent of new cases of legal blindness in Canada. Risk factors include age, a genetic predisposition, a history of smoking and sun damage to the eye. Although there is no cure for the condition, the following strategies could reduce your chances of getting it or slow progression if you do.
Use UV protection with sunglasses and hats
Eat dark, leafy veggies like kale and spinach, which contain lutein, an antioxidant that has been nicknamed “the eye vitamin” and helps protect the eye by filtering out damaging sunlight
Be active, which keeps blood flowing to the macula
Get annual eye exams
With the help of powerful imaging techniques, such as spectral domain optical coherence tomography and hyperspectral imaging, researchers are investigating a link between specific ocular and visual changes in the eye related to the onset of Alzheimer’s disease. With these techniques, optometrists may be able to offer early detection of the disease.
Untreated hearing loss is a big issue, explains Calgary-based audiologist Carrie Scarff, PhD. A 2012-2015 Canada Health Measures Survey reported that 78 per cent of adults 60 to 79 years old have at least slight hearing loss in one or both ears.
This increases the risk of social withdrawal, depression and even cognitive decline.
Think of the ears as a muscle; if you are not getting enough aural stimulation, electrical activity from the auditory nerve to the brain starts to diminish. Hair cells within the ear contribute to the ability to hear, but can become damaged as you age, which means that your brain may not be able to make sense of what you are hearing. In fact, recent research out of Johns Hopkins Medical Center has noted that after only 4.5 years of hearing loss, functional MRIs have picked up “significant atrophy” of the brain.
If you do not hear as well as you used to, or if you are 60 years old or older, get a thorough quality hearing assessment, suggests Scarff. Use assistive devices if they are recommended. For example, Scarff uses aids for a mild hearing loss and can go for a run and comfortably listen to podcasts on her phone. Preserve the hearing you have by using protective ear muffs or earplugs to muffle loud sounds. Keep the brain active by listening to music and having casual conversations.
Treat the ears well, she says. “They are the doorway to our communication.”
“Issues that affect the mouth can have systemic effects on the rest of the body,” says Dr. Bruce Yaholnitsky, a Calgary periodontist. Take periodontal gum disease (PGD), for example.
“PGD is a chronic infection that results in low-grade inflammation in the soft tissues around the teeth,” he explains. It is a more aggressive condition than garden-variety gingivitis, which affects 32 per cent of the population aged 20 and over. Warning signs for PGD include bleeding gums, but this condition may not be diagnosed until advanced stages when teeth become loose or abscesses develop.
Recently, PGD has been linked with an increased risk of developing dementia. A first-of-its-kind study from the University of Illinois discovered that mice with gram-negative anaerobic bacteria — a dangerous component of PGD — developed more amyloid structures (toxic protein clumps that interfere with cell function) in the brain than mice without the bacteria. “You were able to see the neuropathology,” says Yaholnitsky.
The good news is that PGD is preventable. With quality brushing twice a day, flossing at least once a day and regular gum tissue exams and maintenance from your dentist or periodontist, you should be fine.
“Good oral care with regular professional evaluation is important,” Yaholnitsky says. “And the sooner you do this, the better. When you are 20, you don’t worry about dementia, but that is when gum disease begins.”
“Smell is connected to food, memory and emotion. It adds colour to our lives,” says Jamie Knight, a PhD student with the faculty of psychology at the University of Victoria (UVic). “But historically, olfaction has been an understudied area.”
That is changing.
Once standardized, empirical tests were developed in the mid-1980s, “research exploded.” We now know that losing our sense of smell can happen as a result of colds (temporary), repeated sinus infections, viruses, certain medications or from head injuries. We also know that cognitive and memory test scores worsen as you lose your sense of smell. Knight is digging deeper into this connection, looking into a variety of factors including how recovering smell may reduce the rate of any cognitive decline.
As far as the smell recovery process is concerned, there is good news on the horizon: neurons in the olfactory pathway regenerate. Knight is working on seeing if something called “smell training” helps speed up the process. This involves a daily process of stimulating the sense of smell with potent aromas (rose, eucalyptus, lemon and clove oils are popular) to re-awaken olfactory function. “It is like nasal physiotherapy,” Knight says. This year, she will conduct a smell training intervention study at UVic, which will be the first of its kind in Canada.
In the meantime, nose care is important to keep that smell function intact. Knight recommends exercising to keep the blood flowing to the nose and paying attention to scents (literally, stopping to smell the roses). Keeping your nose warm, by covering it with a scarf in cold weather, for example, will also ensure your immune system remains strong to keep toxic viruses at bay. [ ]