Many people could greatly improve their odds against developing dementia by making four, low-cost lifestyle changes, Western researchers have discovered.

In the first study of its kind, researchers at Lawson Research Institute (Lawson) and Schulich School of Medicine & Dentistry found about half of dementia cases in Canada can be influenced by 12 lifestyle factors.

Topping the “dirty dozen” list across Canadians’ lifespans, and especially notable from midlife onwards, are physical inactivity, hearing loss, obesity and hypertension.

“While lifestyle changes aren’t a magic pill to prevent all dementias, they’re an empowering way to reduce the overall risk,” said Surim Son, study lead author and Ph.D. candidate at Schulich Medicine & Dentistry and Lawson

“We’re talking about significant benefits to Canadian health and health systems.”

The findings could also have profound implications in refocusing health-policy priorities. The Public Health Agency of Canada is already highlighting the study as part of its resources for national health policy advisors, she noted.

This study is the first to weigh Canadians’ lifestyles and habits against 12 potentially modifiable risk factors for dementia, and the first globally to include sleep disruption on the list.

Son’s paper, published in The Journal of Prevention of Alzheimer’s Disease, builds on a 2017 study in the Lancet that shows 12 modifiable risk factors throughout the course of life could contribute to 40% of dementias around the world.

But Canada’s numbers are considerably higher because more of us indulge in weightier lifestyle risks. For example, four of every five older Canadian adults don’t exercise regularly, one in three is obese or has hypertension and one in five has hearing loss.

“If half of the dementia cases in Canada are linked to modifiable lifestyle risk factors, this suggests that, today, prevention may be the most effective form of treatment,” said Dr. Manuel Montero-Odasso, co-author of the paper and Schulich professor in the departments of medicine and epidemiology and biostatistics. He’s also the director of the Brain & Gait Lab at St. Joseph’s Parkwood Institute.

“Dementia doesn’t have to be your destiny, even if that’s part of your genetic story. Our results show almost everyone can change their risk factors and improve their cognitive resilience.”

Montero-Odasso advice is “Go out for a walk and keep moving. Get a hearing assessment. Keep your blood pressure in check. It’s low-cost and easy to implement. It’s good for your body health, even beyond improving your brain health and reducing your dementia risk.”

The 12 potential modifiable factors (based on a study of 30,000 Canadians over the age of 45), weighted from most significant factor to least:

• Physical inactivity
• Hearing loss
• Obesity
• Hypertension
• Traumatic brain injury
• Depression
• Less education in early life
• Sleep disturbances
• Diabetes
• Smoking
• Excessive alcohol
• Social isolation