Dementia and Alzheimer’s disease may not be an inevitable part of aging, according to a recent Dutch study, which identified 100-year-olds with high cognitive performance despite risk factors for deterioration.
This six-year study of centenarians – people over the age of 100 – found that despite high levels of a brain marker associated with cognitive decline called amyloid beta, these centenarians were still sharp and performed well on cognitive tests. The researchers concluded that these older subjects may have resilience mechanisms that protect them from memory loss.
In fact, they said the risk of dementia doesn’t necessarily have to be higher once you’ve passed your 100th birthday.
“A person between 70 and 95 years old is exposed to the same risk of dementia as someone between 100 and 102 years old,” said Henne Holstege, Ph.D., of Amsterdam University Medical College in the Netherlands, who was involved in the study.
These results give some a hopeful glimpse that while dementia and Alzheimer’s are more common with age, it won’t be everyone’s fate.
“Age is the No. 1 risk factor for Alzheimer’s disease, but these findings show us that centenarians may thrive despite their advanced age,” says Dr. Richard Isaacson, director of the Alzheimer’s Prevention Clinic at Weill Cornell Medicine and New York-Presbyterian Hospital, who led the study.
While these findings shed light on aging and cognitive functioning, according to some experts, it still remains a complex phenomenon that requires further investigation.
“Dementia and Alzheimer’s disease are mostly multifactorial conditions, meaning that a mix of genetics, age, environment, lifestyle behaviors and medical conditions coexist and can lead a person towards or away from cognitive decline,” said Isaacson.
Researchers are still not sure why some people are protected from cognitive decline, while others are spared. The researchers in the study suggested that some of these protective factors could be related to cognitive performance, education, frequent cognitive activity, and even IQ. But more can play.
“There may be protective immunological and cardiovascular risk factors that help keep their brains resilient and cognitively functional, even in old age,” says Dr. Gayatri Devi, a neurologist and psychiatrist at Lenox Hill Hospital in New York City.
The role that the brain markers analyzed in the study play on memory, including a sticky plaque called amyloid beta typically found in the brains of people with Alzheimer’s, is now hotly debated among experts. The varying presence of these markers in this study further adds to this complicated process.
“It is important to understand that the presence of amyloid in the brain does not definitively mean that someone will develop dementia,” said Isaacson. “There are other factors and lifestyle behaviors that can make us resilient and resistant to cognitive decline.”
It is important to note that there are some caveats to this study. For example, the brain markers were only analyzed in 44 of the participants, so the findings may not apply to everyone, and more research needs to be done to learn more about the complexities of aging.
Other studies have explored the prevention of cognitive decline. According to the 2020 Lancet Commission Report, 40% of dementia cases can be prevented based on modifiable risk factors. Some of these previous studies have been successful in improving cognitive function and reducing risk.
A study by Isaacson’s team at the Alzheimer’s Prevention Clinic found that it was possible to improve cognitive function and reduce risk, especially in those who followed lifestyle modification suggestions such as exercise, diet, vascular risk, and medications.
While more is being discovered and discussed, experts still recommend maintaining a healthy lifestyle, including balanced eating, exercise, and doctor’s visits, to maintain cognition as you age.
“It’s essential for people at risk to see their doctor regularly and consider cognitive screening tests,” Isaacson said.
Alexis E. Carrington, MD, is a dermatology researcher at the University of California, Davis and an associate of the ABC News Medical Unit.