Which areas of the brain are most vulnerable to Alzheimer’s disease?
Late-maturing regions of the brain are most vulnerable to aging
Dr Cividini presented a study she carried out with colleagues to investigate typical cortical thinning changes in aging healthy brains that might reveal vulnerability to neurodegeneration.
The team carried out magnetic resonance imaging on 128 healthy individuals and estimated cortical thickness in 83 regions and the cortical thickness trajectory with increasing age.1
Cortical thinning was most evident in the temporal, frontal and parietal lobes, said Dr Cividini, and least evident in occipital regions and motor and premotor areas.1
It’s never too early or too late to take action to prevent Alzheimer’s disease
The results from the study are consistent with the “last-in, first-out” hypothesis in which late-maturing regions of the brain are most vulnerable to aging, concluded Dr Cividini. Such thinning in the temporal, frontal and parietal lobes might therefore have a crucial role as an additive risk factor for age-related neurodegeneration.1
Brain resilience vs vulnerability to Alzheimer’s disease
How can we build a better brain as we get older? asked Professor James Galvin, University of Miami Miller School of Medicine, FL.
Modifying 12 risk factors — alcohol and tobacco consumption, air pollution, head injury, poor education, hypertension, hearing impairment, obesity, depression, physical inactivity, poor social engagement, and diabetes — can lower the risk of Alzheimer’s disease by about 40%.2
Modifying and controlling 12 risk factors can lower the risk of Alzheimer’s disease by about 40%
Although other risk factors such as age, sex, genes, and family history cannot be controlled, individuals vary in their resilience or vulnerability to Alzheimer’s disease, added Professor Galvin. Resilience may offer protection from a poor environment, whereas vulnerability may be lessened by a good environment.
Measuring brain resilience and vulnerability to Alzheimer’s disease
Professor Galvin described tools he has developed with his colleagues to measure brain resilience and vulnerability to Alzheimer’s disease:
- The Resilience Index (RI) provides a quantifiable measure of brain health and risk of cognitive impairment and dementia3
- The Vulnerability Index (VI) identifies individuals with a high risk for cognitive impairment4
A low RI or a high VI in asymptomatic individuals can inform personalized treatment plans to support brain health
The RI combines physical activity, cognitive activity, social engagements, dietary pattern, mindfulness, and cognitive reserve resulting in a range of scores from 1–378, explained Professor Galvin. It shows good discrimination between individuals with and without cognitive impairment (area under the curve [AUC] 0.836; 95% confidence interval [CI] 0.774–0.897).3
The VI combines 12 easily obtained modifiable and nonmodifiable sociodemographic, medical, and functional factors including age, sex, race, ethnicity, education, frailty, obesity, and medical comorbidities; and also accurately discriminates between individuals with and without cognitive impairment (AUC 0.844; 95% CI 0.776–0.913).
A low RI or a high VI in asymptomatic individuals can therefore inform personalized treatment plans to support brain health, concluded Professor Galvin.