• A new study by researchers at the University of California at Irvine,found that people aged 90 and over, who exhibit superior cognition, exhibit brain pathology comparable to that of patients with Alzheimer’s disease.
  • These findings prompted researchers to investigate the link between lifestyle habits, health conditions, and higher cognition in the 90+ age group.
  • Autopsy data and cognitive test results were reviewed to understand participants’ cognitive function and brain health, finding similar levels of Alzheimer’s pathology.

In the United States, the number of people aged 90 and over has nearly tripled over the past three decades and is expected to quadruple over the next 40 years.

The main risk factor for cognitive problems, including Alzheimer’s disease, Lewy body disease and related dementias, is age.

As people age, there is a greater likelihood of experiencing problems with memory and brain function. However, there is little data available on the brain changes that occur in people aged 90 and over who retain excellent cognitive abilities, despite their age.

Now, new research, published in the Alzheimer’s Disease Journalshows that although the “oldest” individuals, those who live to be 90 years old or more, may possess superior cognitive abilities, these individuals present a cerebral pathology comparable to that of Alzheimer’s patients.

THE 90+ Study, launched in 2003, is a longitudinal research project studying aging and dementia. Its main purpose is to study the older population, which is the fastest growing age group in the United States.

With more than 1,600 registered participants, it has become one of the largest studies of its type in the world.

Throughout the project, significant findings have been obtained, shedding light on the cognitive functions, health and lifestyles of older people, based on information collected during their lifetime.

Similar levels of Alzheimer’s pathology

According to the researchers of this new study, people aged 90 or older who still maintain good memory and thinking skills tend to have similar levels of Alzheimer’s disease in their brains.

Researchers sought to understand why some very old people can still think clearly and have good memories.

With that in mind, they focused on a group of very old individuals with excellent cognitive abilities, as they wanted to see if there were any changes in their brains that might explain this.

Specifically, they looked at the link between Alzheimer’s disease – a common cause of memory problems – and other brain changes that are unrelated to Alzheimer’s disease.

Research suggests that although Alzheimer’s disease-related changes and vascular changes are common in their brains, these people are less vulnerable to other forms of neurodegenerative changes like Lewy body disease.

The study results were obtained by analyzing autopsy data from 102 cognitively normal people who died at an average age of 97.6 years.

Results of cognitive tests taken between 2 and 12 months before their death were also included, and the average age of study participants at their last visit was 97.1 years.

Ability to resist negative brain changes

Researchers found that older people with excellent cognitive abilities were able to withstand the negative effects of Alzheimer’s disease-related brain changes and low levels of damage caused by vascular problems.

These people were also resistant to other types of brain changes that are unrelated to Alzheimer’s disease and multiple other brain health issues.

By understanding what factors allow these people to resist these changes, we can gain valuable information on how to maintain good cognitive abilities despite aging.

Dr. Roshni Biswasfrom the Department of Neurology at the University of California, one of the study’s co-authors, explained the key findings to Medical News Todaysay that “people who live to be 90 and older with excellent memory and thinking skills tend to have similar levels of Alzheimer’s disease pathology in their brains, but have lower levels of other pathologies diseases that cause memory and thinking problems.

Dr. Biswas pointed out that these participants also had fewer coexisting brain pathologies:

“Over the past 30 years, the number of people aged 90 and older in the United States has nearly tripled, and that number is expected to quadruple over the next four decades. Given this significant increase in the number of older people, it is crucial to prioritize research to understand the factors that promote both quality and quantity of life for those reaching their 90th birthday.

Dr Biswas pointed out that this research “provides evidence that it is possible to maintain excellent memory and thinking skills even after age 90 and in the presence of abnormal age-related brain changes”.

However, “further research into the factors that allow these individuals to maintain intact cognitive abilities could provide insights into how to maintain cognitive health despite advancing age,” Dr. Biswas explained.

“Several important takeaways”

Dr. Ari D. Kalechsteinpresident and CEO of Executive Mental Health, not involved in this research, said DTM that “the affirmation intuitively makes sense”.

“Cognition is an indicator of brain integrity. To the extent that the brain is compromised by neurodegenerative disease, including but not limited to conditions such as Alzheimer’s disease and stroke, cognition will be affected.

Dr. Kalechstein pointed out that “there are several important takeaways from this study and similar studies.”

“First, it is important to refrain from using sweeping generalizations about age and functional ability, for example, whether an individual can perform the usual and customary duties of being a senator This does not negate a well-established finding that older adults are at risk of cognitive decline, rather it means that such an outcome should not be assumed,” he explained.

“Furthermore, it will be interesting to see if this study serves as a catalyst for future investigations that may seek to identify factors that protect cognition in ‘older people’,” he noted.

“Yes, there are many studies that have looked at this important question and there are theories that focus on this specific question, for example, the reserve capacity of the brain; Nonetheless, future studies may improve what is known and/or serve as a cornerstone for a new theory that better explains why a subset of adults are more resilient than others with respect to adverse effects. of age on cognition.

– Dr. Ari D. Kalechstein