🧠 Over 80 years old and exceptional memory: how is this possible?

Some older people, over 80 years old, maintain mental agility and exceptional memory. How do they manage to preserve cognitive abilities similar to those of people aged 50 or 60? A recent publication in Alzheimer's & Dementia provides insights into the potential genetic factors behind this remarkable brain preservation.

Conducted by researchers from Vanderbilt University, this investigation focused on the genetic variants present in these people with high memory performance. The goal was to determine if specific genes are associated with this form of successful aging, by comparing these "super-seniors" to other groups of the same age.

The results reveal a marked difference in the presence of the APOE-ε4 variant, known to increase the risk of developing Alzheimer's disease. Super-seniors are much less likely to carry this gene compared to people of the same age with dementia. This observation indicates that the absence of this risk factor could contribute to their cognitive resilience, even in the face of normal aging.

Furthermore, the team noted a higher frequency of the APOE-ε2 variant among super-seniors. This gene is often linked to protection against Alzheimer's disease. Its increased presence suggests it could offer an additional advantage, helping to preserve brain functions over the years, which supports the idea of a genetic influence on long-term mental health.

To reach these findings, the study analyzed data from over 18,000 participants, drawn from several national aging cohorts. Super-seniors were defined as people aged 80 or over whose memory scores exceeded the average of those observed in cognitively normal adults aged 50 to 64. This approach allowed for the inclusion of a diversity of profiles, with representatives from different ethnic backgrounds, for a more robust analysis.

The researchers explain that these findings encourage using the super-senior phenotype to identify mechanisms of resistance to Alzheimer's disease. This work, the largest to date on this subject, offers new perspectives for understanding how certain genes can modulate the development of dementia and the ability to age with good mental health.

Thus, this work highlights the potential role of genetics in preserving cognitive functions in the elderly. It suggests avenues for future research aimed at discovering ways to promote healthy brain aging, drawing inspiration from the characteristics of these exceptional individuals.