Developing Resilience from Alzheimer’s Disease

Some people have all the risk factors for Alzheimer’s but never develop the disorder.

Alzheimer’s Disease can be characterized as a progressive, long-lasting neurodegenerative disorder at its core. By the time symptoms develop, the disease has already pathologized in many aspects. However, for some people who have a strong genetic propensity to experience Alzheimer’s Disease, the classical symptoms will never be experienced. Why is it the case that only some with the highest statistical probability of A.D ever develop outward signs of it?

Resilience to A.D lowers symptom severity in patients

Resilience to A.D can be defined as the brain’s ability to properly function in spite of the fact that many of the signs associated with Alzheimer’s are present in it. In patients with higher levels of cognitive resilience, core pathogenic components associated with Alzheimer’s have manifested, yet somehow these alterations do not impede neurological functioning to the extent that symptoms happen. For these individuals, the presence of Amyloid Beta plaque formation, neurofibrillary tangles, and vascular alterations correlated with the progression of A.D does not seem to significantly hamper brain activity.

There are numerous factors that seem to be linked to resilience in those with A.D pathology.

1. Resistance to brain damage from the plaques associated with A.D

For those who are resilient to A.D, the disease pathology seems to do less brain damage than expected. Consequently, some patients who experience a degree of resilience can function cognitively normal without significant brain damage despite the presence of neurotoxic plaques.

2. Being able to maintain good cognition despite the presence of factors which should reduce it

For other individuals resilient to Alzheimer’s, the plaques do inflict significant brain damage, yet that damage does not seem to impact cognition as much as it should. For one reason or another, some patients seem to be resilient to the structural damage that coincides with the development of A.D.

3. Possessing more effective neurological compensation for the alterations linked to Alzheimer’s Disease

Alzheimer’s Disease is a very heterogeneous disorder. In fact, there is no single root-cause of its pathology, but rather a culmination of hundreds of individual changes over the course of the afflicted individual’s lifetime. The ability of resilient brains to cope more effectively with these multitudes of changes leads them to be more capable of maintaining relatively normal activity.

4. Having a high cognitive reserve

Cognitive reserve is the ability the brain has to reserve its functional capacity in spite of significant changes. There are many different lifestyle habits that can increase cognitive reserve, such as occupational attainment, regular exercise, and engaging in leisure activities.

5. Maintenance of steady metabolism

Insulin resistance has been previously linked to the progression of Alzheimer’s Disease. For reasons still not yet known, insulin metabolism issues can contribute substantially to the alterations associated with A.D. In fact, mitochondrial dysfunction can explain a significant portion of the symptoms associated with A.D diagnosis. Some patients who are resilient to A.D may have improved mitochondrial functioning that can effectively compensate for the changes that characterize Alzheimer’s pathogenesis.

What can I do to develop A.D resilience?

A recent genome wide association study (GWAS) conducted by researchers at the University of Vanderbilt found that specific lifestyle habits are related to an increased likelihood of developing a resilience to Alzheimer’s Disease. Individuals who had a higher level of education, a diagnosis of obsessive-compulsive disorder, who began smoking at an older age, and were born from older mothers had the lowest likelihood of experiencing A.D symptoms, despite pathological manifestation of the disorder. Conversely, the study linked smoking at a young age, a diagnosis with Attention Deficit Hyperactivity Disorder, and the number of cigarettes consumed per day, with a succinctly higher probability of experiencing the symptoms of A.D upon pathology.

The researchers also found specific genes that may confer differential levels of resilience to A.D associated dysfunction. Interestingly, some of these protective genes can even be activated as a result of lifestyle changes. Lifestyle activities such as regular exercise, maintaining a strong social support group, and eating a well-balanced diet have all been correlated with increased resilience to A.D.