When it comes to dementia, certain risk factors, such as aging and genetics, can’t be changed. But other risk factors are modifiable, and knowing what they are can help you take steps to minimize their impact and protect your brain. In research published at the end of March in the journal Nature Communications, scientists looked at 15 modifiable risk factors and found that three are the most harmful.
“We know that a constellation of brain regions degenerates earlier in aging, and in this new study we have shown that these specific parts of the brain are most vulnerable to diabetes, traffic-related air pollution (increasingly a major player in dementia), and alcohol,” said the study coauthor Gwenaëlle Douaud, PhD, an associate professor with the Nuffield Department of Clinical Neurosciences at the University of Oxford in England, in a statement.
The results suggest that certain lifestyle changes could potentially help protect the brain from these risk factors. People can cut back on alcohol consumption, follow a healthy routine of diet and exercise to prevent or reverse diabetes, and try to avoid situations where heavy air pollution is present.
Finding the Influences That Increase Degeneration
In previous research, the scientists had pinpointed a “weak spot” in the brain — a specific network of higher-order regions that not only develop later during adolescence, but also show earlier degeneration later in life. They discovered that this brain network is particularly vulnerable to schizophrenia and Alzheimer’s disease.
For this new study, Dr. Douaud and her collaborators examined the brain scans of 40,000 adults in the United Kingdom between the ages of 44 and 82 to determine how the fragile brain regions were affected by genetic and modifiable factors — those that can potentially be changed throughout life to reduce the risk of dementia.
They separated the modifiable influences into 15 broad categories:
Blood pressure, Cholesterol, Weight, Smoking, Depression, Inflammation, Hearing, Sleep, Socialization,
Diet, Physical activity, Education, Pollution (the amount of nitrogen oxide in the air),Diabetes
Frequency of alcohol intake
After the last three, the most significant dementia risk factors were found to be sleep, weight, smoking, and blood pressure. Claire Sexton, DPhil, the senior director of scientific programs and outreach for the Alzheimer’s Association, notes that these latest findings align with prior research regarding habits and conditions that can increase the likelihood of cognitive decline.
“These are well-known risk factors for dementia, so their association with a vulnerable brain network seems very plausible,” says Dr. Sexton, who was not involved in the investigation. “More research is vital in representative populations to replicate and confirm these results.”
Addressing Those Elements That Impact the Brain
Dementia — a loss of memory, language, problem-solving, and other thinking abilities — affects millions of people and is more common as people grow older. About one-third of all people age 85 or older may have some form of dementia, according to the National Institute on Aging.
Dementia does not have to be inevitable, however. The Centers for Disease Control and Prevention estimates that up to 40 percent of dementia cases may be prevented or delayed.
Yuko Hara, PhD, the director of aging and Alzheimer's prevention at the Alzheimer’s Drug Discovery Foundation, further explains why some factors heighten dementia risk and suggests ways to reduce them. Traffic exhaust is a hazard because the burning of fossil fuels creates nitrogen dioxide. Just as with diabetes and alcohol, this pollutant may harm the brain indirectly through increasing risk of cardiovascular disease (which is a known risk factor for dementia). The pollutant may also directly enter the brain, causing changes such as inflammation.
“Although air pollution cannot be entirely avoided, there are steps you can take to reduce your exposure,” says Dr. Hara, who was not involved in the study. “For example, you can monitor air pollution levels in your area online or with an app and stay indoors on days with particularly high air pollution. You can also limit exposure to car exhaust by closing vents and windows while in heavy traffic.”
She adds that brain imaging research has shown that people who drank more than 14 units of alcohol per week showed significantly greater loss of brain volume than those who drank fewer than seven units per week.
Furthermore, people with diabetes have an up to 73 percent increased risk of dementia and a twofold higher risk of vascular dementia than non-diabetics.
Maintaining Hearing, Social Ties, and Learning May Also Stave Off Cognitive Decline
Although not as high on the list as other risk factors, hearing loss and education were also identified as factors that influence the possibility of developing dementia. Hearing loss may negatively impact brain function, as well as contribute to social isolation and depression, which are both risk factors for dementia, according to Hara.
Research has shown that correcting hearing loss with a hearing aid and repeated counseling sessions with an audiologist, to aid in proper use and adjustment of the devices, resulted in a 48 percent slowing of global cognitive decline in older people with untreated hearing loss.
When it comes to education, Hara says that lifelong learning is associated with better cognitive health and higher levels of cognitive activity at mid- or late-life. “Education is modifiable because you can always incorporate learning new things into your life, like taking a new class, learning a new language, learning how to play a musical instrument, or learning a new dance,” says Hara.
Key Takeaways
· Diabetes, exposure to air pollution, and alcohol are the top three modifiable contributors to the development of dementia, according to a recent study.
· Exercise, a healthy diet, staying indoors on high pollution days, and limiting alcohol can decrease the risk of dementia.
· To protect your brain as you age, use a hearing aid when needed, maintain social ties, and continue learning throughout your life.
As always stay healthy and take care of yourself.
Dr. James A Vito,D.M.D.